Pyramid Science

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Thursday, March 29, 2007

Abdominal Training

Maintaining a correct curve in the lower back is important in overall spinal health. Repeated bending movements overstretch the spine and can cause damage. Pain or 'strange feelings' in the legs could be caused by an injury to your back. Disc needs regular movement to stay healthy. Repeated bending squeezes the discs. The damage accumulates and discs can suddenly burst - slipped disc.

Rapid movements can jolt the small facet joints at the back of spine over and over again. Exercises which use the middle part of joint's movement are safer than those which take the joint over to the end point of its movement. Movement of the pelvis directly affects the lumbar spine. In the neutral position the spine is correctly aligned and the spinal tissues are held at the right length. The deep trunk muscles make the spine more stable, holding the spinal bones together. It is the muscles on the surface which cause movement and if the hip flexor muscle is worked too hard it will pull on the lower spine, dangerously increasing the pressure within the disc. A muscle can only pull - it cannot push.

The three types of muscle action are concentric (lifting), isometric (holding) and eccentric (lowering). When deciding on an exercise, consider its type (which muscles are working), the duration (how long it lasts), frequency (how often performed) and intensity (how hard the exercise is). For an exercise to be truly 'specific' it must closely match the action which is to be improved. The trunk muscles must be able to effectively hold the spine in a stable position before any vigorous trunk exercise is attempted. Ideally, a programme begins by improving spinal stability and moves on to improve general movements.

All the fitness components must be balanced for optimal health. The quality (control) of an exercise is always more important than the quantity (number of repetitions) that can be performed. The spine is in its neutral position when the pelvis is level and the lower back is slightly hollow. Use the neutral position as often as possible to safeguard your back. Over time, as an exercise becomes easier then it must be made harder if any progress is to be made and so maintain the training effect.

Posture will affect the way you exercise, and the exercises you choose will in turn alter your posture. In an optimal posture the body segments are correctly aligned, so very little effort is needed to maintain the position. In the hollow back posture, the lumbar curve is excessive and the abdominal muscles are lengthened. In the round back posture the chin pokes forward, and the shoulders are rounded. The chest muscles are tight and the muscles controlling the shoulder blades are weak. In the swayback posture the hip and pelvis are thrust forwards and the body slouches. In the flatback posture, the normal lumbar curve is lost, and the lower back appears stiff.

The amount of body fat you have is more important than your weight. The most effective way to trim yourself down, and keep that way, is to combine a high quality, balanced diet with regular exercise. When the amount of energy coming into your body as food equals the amount going out through activity and exercise, you are said to be in 'energy balance'. Regular exercise is essential for effective, long-term weight loss. Our bodies combine tendencies towards being fat, lean and muscled. The combination of these factors you were born with determines your body type.

Training Style

Bending your the legs in a sit-up reduces the unwanted forces on the lower back. Do not allow the legs to move into a horizontal position when performing a leg raise action. The trunk crunch is an advanced exercise to be used only after initial abdominal strength has been gained using other exercises. The crunch focuses on the upper abdominal region and must be balanced by movements which emphasise the lower abdominal area, such as the pelvic raise. The knee raise can place stress on the lower back if it is performed with a 'swinging' action. Keep the action under control at all times, especially when lowering the legs.

Leverage is greatest when a lever is in a horizontal position. If an exercise doesn't allow you to keep your spine vertical, place your hand on something for support. Looking at the pelvis gives an important indication of lumbar spine position. Keep movements slow and controlled and use the middle of a joint's total movement more often than the ends. Try to keep your spine in the neutral position as often as possible and avoid nodding your head when performing any abdominal exercises. Wear comfortable clothing, and warm up gradually before beginning an abdominal training programme.

In water, buoyancy is related to body density. Thinner and muscular individuals tend to sink, while those with high body fat will float. Buoyancy can be used to assist or resist a movement, and to support a body part during exercise. Less streamlined objects offer greater water resistance, and can be used to make an exercise harder.

Summary

The spine is divided into regions: cervical (neck), thoracic (rib cage), lumbar (lower back), sacrum and coccyx (tailbone). The spine forms an 'S' curve, making it naturally springy. Bending and straightening the spine stretches and relaxes the spinal ligaments. Nerves transmit electrical messages for movement and feeling and if a nerve is trapped, movement and feeling can alter, giving weakness, pain or tingling.

The disc contains gel and acts as a shock absorber. Safe movement keeps the discs healthy but poor movements allow stress to build up in the discs over many years. Mid-range is the centre part of the total extent of movement possible at a joint. In its neutral position, the spine is correctly aligned and the spinal tissues are only at their normal length.

The split in the abdominal muscles that occurs during pregnancy is called a 'diastasis'. This may be larger if you have a narrow pelvis, or if you have a large baby or twins. The diastasis may be larger if you are overweight or have poor abdominal tone. The abdominal hollowing exercise can help regain your figure, but vigorous abdominal training is dangerous after pregnancy. Correct posture is important after pregnancy to help prevent back pain.

In an optimal posture - the hip, shoulder and ear lie in a vertical line. The pelvis is level and the lower spine should be gently hollowed. The inner edge of the shoulder blades are 4-5 in (10-12cm).

Body fat is much more critical than actual body weight. Your weight will include muscle, bone, tissues and fluids as well as fat. The feeding control mechanism (FCM) in the brain attempts to match the amount of energy you take in as food to the amount you burn off through physical activity. Starches and sugars are the energy-providing foods (carbohydrate). Fat is an energy store and is therefore high in calories.

Physical exercise increases your body's tick-over, the basal metabolic rate (BMR), reactivates your feeding control mechanism and increases muscle tone. You cannot substantially change the body type you were born with, but correct training can significantly adapt it.

Monday, March 26, 2007

Drug (Therapeutic) Evaluation

Clinical trial

The following is not original and the source is not known.
No accreditation can be given, except this statement.

In the drug development process, The Food and Drug Administration (FDA) in the USA requires that all potential drug treatments pass through several phases of experimentation and review before they are deemed safe and effective in treating a disease, such as Alzheimers. This approval process usually takes more than 10 years, from start to finish, and involves the following steps:

Preclinical Testing - Phase I
Clinical Trials - Phase II
Clinical Trials - Phase III
Clinical Trials - The New Drug Application (NDA)
FDA Review
Continued Studies

Preclinical Testing

One purpose of preclinical testing is to establish a "mechanism of action" for the drug compound, which involves a close examination of how the drug works. Test tube studies are performed to seek out potential benefits of the drug compound and to learn how the drug interacts with other substances within a test tube (in vitro). Drug compounds for Alzheimers are tested against various processes thought to be involved in the disease, such as accumulation of amyloid, the presence of apolipoprotein E4, or deficiencies in certain neurotransmitters. During these studies, researchers are looking for both effective and potentially harmful interactions between the drug and other molecules.

Next, the drug is tested in animal studies in order to determine its ability to achieve desirable results (preclinical efficacy). Used as partial models for Alzheimers disease, both aged animals and those suffering from neurological defects are tested to see how the drug acts within a living system (in vivo), and how a living system, in turn, reacts to the drug. Varying doses of the experimental drug are administered to test the drugs ability to improve performance and behavior in animals, and to reveal harmful side-effects that may occur. Further testing also is done to determine the toxicity of the drug, whether it may be cancer-causing, or whether it is likely to cause genetic mutation within living systems. Based on results from these studies, the drug compound may be altered slightly to make it more effective. Animal studies are an integral part of most drug studies because they help researchers predict reactions in living organisms before the drug is given to humans.

Preclinical testing of a new drug compound can last from one to six years, because extensive data needs to be gathered and analyzed before the drug moves into human studies. If data proves that the experimental drug may be effective in treating a specific disease, the pharmaceutical company will file an Investigational New Drug Application (IND) with the FDA. The IND gives specific details of all experiments completed during the preclinical testing phase, including the chemical structure of the drug compound and how it is manufactured. The IND must also explain how the new drug works in living systems, how it may be beneficial in treating symptoms of the disease, and what side effects it is known to cause.

In this application, the pharmaceutical company also must describe its plans for the next phase of human clinical study, specifically including: how many participants the study will involve; what criteria will be used for enrolling participants; where the studies will take place; and, how drug safety and efficacy will be measured. If the FDA accepts the IND, drug testing in human subjects can begin within 30 days.

Phase I Clinical Trials

Human clinical trials generally occur in three phases. In Phase I clinical trials, the experimental drug is tested in approximately 20-100 healthy volunteers. Researchers are testing to see how the body absorbs, breaks down, and eliminates the drug, and how the drug affects the different organ systems within the body. Different dosage levels of the drug are administered and all side effects are documented. This helps researchers establish appropriate dosage levels and determine what precautions may need to be established (such as warnings about mixing the drug with alcohol or other substances that may cause adverse reactions). As more is known about the safety of the drug, the number of participants in Phase I trials will likely increase. If a new drug provides few therapeutic benefits and causes many harmful side effects, it may fail this round of testing. Phase I clinical trials can take approximately one year to complete before enough data is gathered to begin Phase II clinical trials.

Phase II Clinical Trials

In Phase II clinical trials, the experimental drug is tested in approximately 100-300 individuals who suffer from the disease or condition the drug was intended to treat. At this stage, researchers primary objectives are: (1) to determine the effectiveness of the drug in treating the intended disease or condition; (2) to uncover less common side effects, that may not have appeared during the animal studies or the smaller Phase I clinical trials; and, (3) to determine effective dosage levels and decide how often the drug should be administered. In Phase II, researchers are mostly interested in gathering data about the safety and efficacy of the experimental drug.

During Phase II clinical trials, researchers employ a method known as a double-blind, placebo-controlled study to ensure observations made during these trials remain unbiased. In a double-blind placebo-controlled study, participants are randomly placed into two groups. One group is given the experimental drug, while the other group receives a placebo (sugar pill). The studies are considered double-blind because neither the participants nor the researchers know who is receiving the drug and who is receiving the placebo until after the study is complete. A third party keeps record of this information and can access it if a participant experiences extreme side effects or other complications resulting from the medication.

During the study, participants are carefully monitored and all pertinent information is recorded and analyzed by the researchers. The double-blind placebo-controlled study design prevents researchers from allowing their expectations to influence their observations, and also prevents participants from being influenced by what they expect to gain from using the drug.

Phase III Clinical Trials

Phase II clinical trials can last up to two years. At the end of this round of testing, if the side effects of the drug outweigh the therapeutic effects, it may be dropped from further testing. If the results of Phase II clinical trials are positive, the drug will then move into Phase III trials.

The number of participants involved in a Phase III study of Alzheimer drugs increases considerably -- usually including 1,000 or more people who have received a diagnosis of "probable Alzheimers." As in Phase II, double-blind placebo-controlled studies are employed to ensure accuracy of the data collected. The results of Phase III clinical trials should determine whether the use of the drug is beneficial and if its "user-friendly" (easy to access and administer).

Phase III clinical trials can last from two to four years. The FDA requires results from two completed Phase III studies to ensure accuracy of the findings, and to eliminate the possibility that the findings occurred by chance. If the results of Phase III clinical trials do not show clear, positive results, the drug may be dropped from further study.

Also, during Phase III clinical trials researchers may offer an open-label study to the participants to enhance enrollment. In an open-label study, all participants (both in the experimental drug group and placebo group) who have successfully completed the study are given the option of continuing to take the experimental drug for six months to one year prior to FDA approval. This allows participants to continue receiving the drug treatment until their own physicians can begin prescribing it. At this point, the experimental drug trials are complete, and the pharmaceutical company can move forward to the next step of development by filing a New Drug Application with the FDA.

The New Drug Application, FDA Review and Continued Studies

The New Drug Application (NDA) is an extensive report the pharmaceutical company must submit to the FDA for review. This report gives general information about the drug and its chemical structure, and also includes everything that has been learned about the drug -- from preclinical testing through Phase III clinical trials. The FDA reviews all information collected in order to determine the overall safety of the drug, weighs potential benefits against risks, and ultimately determines whether the drug should be approved for public use. If the amount of information provided in the NDA is not sufficient, the FDA may require future clarification from the pharmaceutical company or request additional testing.

Once the NDA is approved by the FDA, the drug can be made available to the public (usually through a doctor’s prescription). However, testing of the drug does not end at this point; the pharmaceutical company is still required by the FDA to continue submitting reports describing the drugs efficacy and long-term effects, as its use becomes more widespread.

Sunday, March 25, 2007

Background

Stretching is about permanent changes in muscle. Forcefully moving a limb against a tight muscle will rupture that muscle or its tendon. Any ability in sport that requires leg movement can benefit from stretching. It is essential that every major muscle around the hip area and downwards through the legs is permanently modified by stretching. It is impossible to maximise potential in terms of speed without proper conditioning and this starts with flexibility.

Stretching is a science. It must be done correctly or you will NOT get the results you want. Literally weeks are all that are needed to achieve dramatic flexibility improvements if done correctly rather than months or years, if ever. The use of incorrect methods and incorrect body positions will never get results.

There are over twenty major muscles in each half of the body that must be worked. There are at least a further 30 involved. Two calf muscles operate mostly on the foot, but are tied in with the upper leg movement to a small extent. The four quadriceps muscles of the front upper thigh control the straightening (extension) of the lower leg in relation to the upper leg by increasing the angle. The sartorius muscle is also involved.

The three hamstrings at the back of the upper thigh do likewise but in the reverse way by decreasing the angle (flexion): the lower leg is raised towards the thigh. The two abductors at the side of the hip move the leg outwards and three adductor muscles of the inner thigh bring the leg back in towards the centre. Two hip flexor muscles raise the upper leg towards the pelvis and the hip extensor straightens the leg in relation to the pelvis.

Obliques down the side of the trunk allow lateral (sideways) movement relative to the lower body and although the several serratus anterior muscles are small, they are important and pull the shoulder down towards the pelvis. They are involved with twisting movements of the upper body relative to the waist and are tied in with the obliques. The abdominal muscles pull the upper body in line towards the pelvis.

It is important to realise that reducing the angle between the trunk and the top of the thigh as in sit-ups actually uses the hip flexor muscles which connect the lower spine and pelvis to the top of the upper thigh bone. Too many sit-ups can cause low back pain. You should roll forwards by leading with you head and MUST NOT keep your back straight to really hit the abs - to no more than 45° angle.

Complete list of Lower Body Muscles

Muscles of the lower extremities are subdivided into groups, corresponding with the different regions of the limb.

Foot
Dorsal region
_ Extensor brevis digitorum
Plantar region - first layer
_ Abductor minimi digiti
_ Abductor pollicis
_ Flexor brevis digitorum
Plantar region - second layer
_ Flexor accessorius
_ Lumbricales
Plantar region - third layer
_ Adductor pollicis
_ Flexor brevis minimi digiti
_ Flexor brevis pollicis
_ Transversus pedis
Plantar region - fourth layer
_ The interossei

Hip
Gluteal region
_ Gemellus inferior
_ Gemellus superior
_ Gluteus maximus
_ Gluteus medius
_ Gluteus minimus
_ Obturator externus
_ Obturator internus
_ Pyriformis
_ Quadratus femoris

Leg
Anterior tibio-fibular region
_ Extensor longus digitorum
_ Extensor proprius pollicis
_ Peroneus tertius
_ Tibialis anticus
Posterior tibio-fibular region - superficial layer
_ Gastrocnemius
_ Plantaris
_ Soleus
Posterior tibio-fibular region - deep layer
_ Flexor longus pollicis
_ Flexor longus digitorum
_ Popliteus
_ Tibialis posticus
Fibular region
_ Peroneus brevis
_ Peroneus longus

Pelvis
Iliac region
_ Iliacus
_ Psoas magnus
_ Psoas parvus

Thigh
Anterior femoral region
_ Crureus
_ Tensor vaginae femoris
_ Sartorius
_ Rectus femoris
_ Vastus externus
_ Vastus internus
_ Subcrureus

Internal femoral region
_ Gracilis
_ Pectineus
_ Adductor longus
_ Adductor brevis
_ Adductor magnus

Posterior femoral region
_ Biceps femoris
_ Semitendinosus
_ Semimembranosus

Side Kick Stretch

The only muscles involved in the side leg raise are the abductors and adductors. Maintaining the leg in the raised position without assistance will result in a static active stretch. An isometric stretch of the adductor muscles can be done by pulling the leg downwards while being held in this raised position. Turning the toes upwards can produce an isometric or static passive stretch of the sartorius muscle, depending on its condition. Correct posture will not involve the standing leg at all.

Back Kick Stretch

The rearward leg raise involves purely the hip flexors and extensors. The static active type of stretch can be achieved by raising the leg as far upward as possible without assistance using only the contractile power of the extensor muscle (gluteus maximus). Further movement upward converts this to an isometric stretch of the hip flexors. Pressure on the kidney area caused by the enlargement of the extensor muscle can be uncomfortable. The standing leg need not be involved at all if standing upright. Leaning forward will compromise the raised leg stretch and involve hip extensor of the standing leg to maintain posture. Turning the foot outwards to produce balkal will involve an isometric or passive stretch of the sartorius muscle of that leg depending on the condition of the muscle.

Front Kick Stretch

The leg stretch from the straight legged front kick position is performed by raising the leg either gradually with assistance or placing the heel on a high object. This will stretch the hamstrings if they are short. The hip flexors should be completely relaxed. The hip extensors are put under tension but the balance between these and hamstrings becomes apparent as the leg is raised higher. A poorly stretched hamstring will compromise the extension of the hip towards the leg as it is raised. As the hamstrings lengthen in training the hip extensor becomes better stretched. The overall result is a more easily raised leg by both muscle groups becoming more flexible. The static active exercise for the leg (hamstring) is to elevate the leg to the front with an extended knee but supported only by the strength of the hip flexors (to raise the leg) and quadriceps muscles (keep the leg straight). This should completely relax the hip extensors and hamstrings (the antagonists) and allow these muscles to stretch. This is an isotonic (concentric) contraction for the agonist muscles (hip flexors and quadriceps) as the leg is raised which then becomes an isometric quadriceps tension while the leg is held unmoved and unsupported in position by this tension. The muscles opposing them (hip extensors and hamstrings) are then under a static but active stretch. The stretch for the hip flexors and quadriceps would be the opposite where the muscles are lengthened and then tensed - resting on knees and bending over backwards to full knee flexion then using a forceful quadriceps tension.

One of the best methods to stretch and isolate the hamstrings and hip extensors (gluteus maximus) is the position for the "good morning" exercise. With the feet about shoulder width apart, bend over at the waist but ensuring that the back is kept under tension. The lower back should be slightly curved inwards if this is done correctly. Lower the upper body keeping the chin pushed out. The upper body is the load for this stretch but a weight can be used. The hip extensors are slowly stretched out as the hip flexors pull the pelvis downwards in an isotonic negative contraction (the weight of your upper body is the load). The hamstrings and hip extensors tighten the further downwards you go. Keep going downwards as far as you can but make sure the legs are absolutely locked out at the knee and the back remains under tension. If the back tension is relaxed the upper body only hangs by ligament attachments to the hip extensors. This is the classic position of touching the floor in front of you with the palms of your hands - an example of extreme flexibility but not safe. To return to the upright position, the hip extensors are used in a positive contraction. The wider the stance from which you start then the more the hip abductors/adductors are used. The stretch moves from the hamstrings in isolation (narrow stance) outwards to involve the adductors as the starting stance widens, the downward movement being controlled more and more by hip abductors in conjunction with the hip extensors.

The isometric stretch involves tension of the muscles in the back of the upper leg (hamstrings and gluteus maximus). To involve the hamstrings make sure that the heel is positioned on a high object then strongly contract for 5-6 seconds. Relax the muscles then raise the leg higher. To isolate the hip extensors, either place the underside of the upper thigh over someone's shoulder and pull down or raise your bent knee to the highest point and place your foot in a partner's hand and push down. Both are isometric contractions. The second method will promote strength and be put to good use in a stamping (downward) kick. In this motion the hip extensor is strongly used to straighten the leg/hip into line with the spine. A front thrusting kick also benefits from this stretching and strengthening as the knee is brought as far back as possible towards the body prestretching the gluteus maximus. The forceful contraction of the hip extensor then produces the forward push in this kick. Further, the execution of the double front kick (single of twin target) becomes more feasible as the knees can be brought back towards the body more rapidly then extended while jumping upwards. To allow good posture and balance in this kick the body should be leaned forward to counter the rearward reaction as the kick is performed. Well stretched hamstrings are needed to ensure good extension of the knee in straightening the legs.

Inward Circular Leg Swing

Almost the complete reverse of the inward stretching exercise and involving the same muscle groups: hip extensors and flexors and the abductor/adductor antagonists. To some extent the inward movement also brings into play the sartorius muscle during the inward movement where the foot is kept vertical. As the knee is bent during the last phase of the inward movement the sartorius muscle is relaxed. As for the outward equivalent of this exercise full tension on the muscles must be applied by maintaining the maximum range of the circle or the dynamic stretch is lost.

Outward Circular Leg Swing

This movement begins with the pull by adduction inwards of the leg and relaxation of the abductor muscles. A forced inward swing across the body puts these abductor muscles into a dynamic stretch as the leg continues to move inwards. The hip flexors then come into play as the leg is raised still maintaining the stretch of the abductors. The angle should be inwards and upwards. As the leg reaches the top of the movement the hip extensors should be under dynamic stretch with a full contraction of the hip flexors. Continued motion now starts to involve the abductors and they begin to contract to take the leg in the outward direction. The limit of the upward motion should still be maintained to place the hip extensors under continued dynamic stretching conditions. As the leg starts the downward part of the cycle the abductors keep the leg moving outward stretching the adductors dynamically. Finally the hip extensor starts to contract as the leg moves rearward placing the hip flexors under a dynamic stretch. Clearly this exercise is very complex and involves many muscles but is a terrific movement. To benefit from the outward circular leg swing the maximum range of the circle must be maintained. If not then the full dynamic stretching potential is lost and it is simply a strength exercise to lift the leg up and control the downward motion.

Front Leg Raise

The importance of the leg raising exercise cannot be over-emphasised. The correct execution of this movement has a very complex involvement of many muscle groups. The natural movement of the leg is to move inwards as a result of the action of the adductor muscles in the leg. The deliberate outward swing of the leg is to work against this action training them in a dynamic stretch. The result is lengthened adductors.

The hip abductor on the standing leg pulls downwards thereby exerting an upward movement of the pelvis on the unsupported leg. If the abductors are not functioning correctly then the hip will drop and the leg cannot swing without touching the floor. This is known as Trendelenberg's sign. The complex process by which the leg raise is performed can be illustrated as follows:

The hip flexors raise the leg upwards and at the same time the hip abductors maintain the leg position angled slightly outwards throughout the entire movement. The hamstrings are stretched dynamically at the full height of the raise and this stretch is enhanced by keeping the foot and toes pulled back towards the shin. Full knee extension by quadriceps contraction ensures the antagonist muscles (hamstrings) are relaxed. The adductor muscles are relaxed or should be and are dynamically stretched at the full upward and forward position. The downward movement is controlled by gradual relaxation of the and hip flexors as the opposite muscle, the hip extensor, takes over in a contraction. The hip abductors are partially flexed all the time to keep the leg outward against the inward pull of the adductors - those muscles being dynamically stretched. The hip abductors of the opposite leg are in continuous partial flexion to maintain the pelvic position. As the leg moves to the rear the hip flexors play out more as control is transferred to the gluteus maximus extensor muscle for the rearward movement.

Saturday, March 24, 2007

Major Muscles in Lower Body



Motion

To benefit the most from a stretching program it makes sense to be aware of some of the muscles involved so that a mental picture may be created when actually doing the stretch. It should be noted that there can be a perception that a limb makes a muscle work. Make sure the image is correct - the muscle makes the limb move.

The major muscle groups considered here involve the front-of-thigh (quadriceps form a group of four muscles), the hamstrings (a group of three muscles at the back of the thigh), hip flexors and extensors, the adductors (inside thigh) and the hip abductors. Below the knee are the calf muscles. The following list is not comprehensive and should make you realise that as a result of possessing these twenty major muscles in each leg, just between the hip and ankle, it is going to require some extensive stretching to make sure they are all worked properly.

There are also many smaller, but important muscles. Each muscle has a function and all must be stretched equally well or an imbalance of power will inevitably result. The danger is that if some muscles allow greater freedom of movement and are speed and length conditioned better than others then a serious strain or tear could result by a shorter or tighter muscle being forced to move too much, regardless of how much they are warmed up. Stretching is essential for good form, flexibility and safety.

Abductors of the hip
gluteus medius
gluteus minimus


Adductors of the hip
adductor brevis
adductor longus

adductor magnus
gracilis
pectineus


Calf
gastrocnemius
soleus


Extensor of the hip
gluteus maximus

Flexors of the hip
iliacuspsoas major (iliopsoas)

Hamstrings
biceps femoris
semitendinosus

semimembranosus


Quadriceps femoris
rectus femoris
vastus medialis
vastus intermedius
vastus lateralis

Introduction

  • This paper is concerned with both the 'why' and the 'how' quality stretching can be achieved. I want you to consider a car: it is not sensible to tinker with a car unless you know what you are doing. A trained mechanic can turn a machine in poor condition into a highly tuned car with an excellent performance, but someone with no knowledge of cars is likely to cause damage. It is the same with the body. Great care must be exercised in training the body. With good knowledge, experimentation can lead to an individual's enhancement. The information presented here does not provide you with the level of detail to tinker around.

Close attention must be given to the detail of instruction as failure to do this will at the least not produce the desired results, but worse, may cause injury

It is important to get in touch with your body and feel by actually touching or simply sensing the muscles (kinesthenics) as they tighten or relax. It is also important to know which muscles are involved in any action. By knowing this it is possible to deliberately relax a muscle through mental control where the natural reaction is for the muscle to tighten especially when being stretched. This is a natural protection mechanism and must be offset by training. It is fundamental to stretching and improved flexibility.

The difference between an isometric stretch of 5-30 seconds and a static passive stretch (sustained and relaxed) of 15-30 seconds or more must be understood. The former is a deliberate and hard contraction at the full muscle length. The muscle cannot shorten under this contraction as the limb is prevented from moving. The latter is a completely relaxed muscle but at full length working against the natural tendency to contract. It is not easy to learn this control, but is the key to effective stretching.

Consider the waking involuntary stretch: it is just the body mechanism by which muscle length is reset after an overnight general shortening. Just like effective strength training, a muscle should be used in different positions affecting angles, then stretched at all these different angles. Very few movements involve straight extension/flexion along the axis of stretch and involve only those two muscles (groups) and nearly all are executed by transferring load from one or several muscles onto other groups or additionally involving others. The importance of hitting the muscles at all angles cannot be over emphasised. Too little stretching will almost certainly produce an avoidable injury.

Any muscle action involves contraction (or shortening) and stretching (or lengthening). The force of contraction is a measure of the strength and the ability to extend a limb beyond the normal range of movement and is an indication of flexibility or stretching ability. Strength and flexibility cannot be separated in any context where complete control of muscle movement is necessary. Muscles are controlled by the brain directly but indirect pathways also exist. When muscles are tired all sorts of involuntary reflex effects can occur, similarly when emotionally upset - it is difficult to control all muscles in unison. Generally, when muscle is lengthened then it is also weakened. It is absolutely essential to undertake some sort of strengthening of muscles which have been stretched. If this is not done then an injury will occur at some stage. It cannot be predicted when only that it will happen. This paper will not deal comprehensively with strengthening. Many books exist which are better suited for teaching this aspect of training.

It really is crucial that the muscles involved in all aspects of flexibility training are clearly understood. If the correct image is not pictured in the mind then it is difficult and probably impossible to reach full stretching potential using the methods described here. It is necessary to get in touch with your body (kinesthenics) to know which muscle is being stretched and if it should be under tension or not. Some muscles should be relaxed and conscious control is needed to do this. A muscle under tension cannot usually be stretched, but sometimes a deliberate tension and stretch is actually necessary. You need to know what you are doing.

Literally weeks are all that are needed to achieve dramatic flexibility improvements if done correctly rather than months or even years, if ever, using incorrect methods and incorrect body positions.

Many muscles must be stretched in each leg. Moving from the lower body upwards: the two calf muscles operate on the foot mostly but are tied in with the upper leg movement to a small extent. The four quadricep muscles of the front upper thigh control the straightening of the lower leg (tibia) in relation to the upper leg (femur), or extension, by increasing the angle. The sartorius muscle is also involved. The three hamstrings at the back of the upper thigh do likewise but in the reverse action by decreasing the angle (flexion): the lower leg is raised towards the thigh. The two abductors move the leg outwards to the side and three adductor muscles bring the leg back in to the centre. Two hip flexor muscles raise the upper leg towards the pelvis and the hip extensor straightens the leg in relation to the pelvis. Obliques down the side of the trunk allow lateral or sideways movement relative to the lower body. The several serratus anterior muscles are small but important and pull the shoulder down towards the pelvis. They are tied in with the obliques and abdominal muscles which pull the upper body in line towards pelvis. It is important to realise that reducing the angle between the trunk and the top of the thigh (as in situps) actually uses the hip flexor muscles which connect the lower spine and pelvis to the top of the upper thigh bone (femur).

Dynamic flexibility is the ability to perform dynamic movements within the full range of motion of the joints and is best developed by dynamic stretching. This affects the speed receptors in the muscle spindles. This flexibility is the combination of relaxation of antagonist muscles and contraction of the agonist muscles and an example is striking a ball as in football where the quads (quadricep) muscles are contracted to extend the knee and hamstrings are lengthened (stretched out). In conditioning the length of all these muscles the stretching action should not only stretch the quads but also increase the range of movement. This improves the elasticity of muscles and ligaments and co-ordination between the muscles. Further gains in bone and ligaments require long term body changes and requires regular loading over a long period. Joint surfaces change in the long term with this type of stretching.

Flexibility is reduced by fatigue so limit the number of exercises at any one time and increase the frequency of stretching sessions. Experimentation has shown that 30 repetitions (reps) every day twice daily over a 5 day period had twice the gains of the same numbers, but every other day (10 day period). Eight to ten weeks should be enough to achieve muscle elasticity improvements. Perform in 4-5 sets of 8-12 reps each but gradually increasing the amplitude of movement, switching legs after each rep or set. If the range of movement decreases by fatigue then stop. Only do your maximum for full range movements.

Early morning is a good time to do this but without "throwing" the leg up. Use "lifting" or "leading" movements but under full control for the entire movement over its range. Leg movements involve raising to the front and side. Speed training is important for full range movements and overcomes the reflexive muscle protection mechanism that slows a muscle stretch if the muscle spindle detects a movement which is too rapid.

The side leg raise can be with the trunk turned towards the side which also stretches the standing leg adductors or abduction of the raised leg to the side with the trunk fully facing the front. The same muscles are stretched but from a different angle. Remember this is an important element in stretching as much as in strengthening. You should develop your kinesthenic sense generally to feel the muscle involvment and the stretch.

Stretching the trunk must not be neglected. Twisting, bending and rotating movements with a large amplitude can only be performed safely if you are supple.

Always ensure a full warm up before stretching muscle

The joints in the spinal column can be made more flexible with 25-30 reps of an appropriate execercise. Standing or sitting position can both be done, but sitting is better to isolate the trunk and avoid ballistic movements. Move the trunk from side to side keeping the legs and hips immobile. Side bends either from a standing or seated position, but not leaning forward, are both performed with the hands clasped behind neck. Forward bends (seated) should only be done allowing the back to bend properly otherwise thc hamstrings are stretched. This is a different exercise. Back bends (hyperflex) are from the stomach and should raise the trunk upward. Use the arm and back muscles.

Stretching is about permanent changes in muscle. Forcefully moving a limb against a tight muscle will rupture that muscle or its tendon. Any ability in sport that requires leg movement can benefit from stretching. It is essential that every major muscle around the hip area and downwards through the legs is permanently modified by stretching. It is impossible to maximise potential in terms of speed without proper conditioning and this starts with flexibility.

Stretching is a science. It must be done correctly or you will NOT get the results you want. Literally weeks are all that are needed to achieve dramatic flexibility improvements if done correctly rather than months or years, if ever. The use of incorrect methods and incorrect body positions will never get results.

There are nearly twenty (20) major muscles in each half of the body that must be worked and a total of over fifty (50). In each half of the lower body.

Two calf muscles operate mostly on the foot, but are tied in with the upper leg movement to a small extent. The four quadriceps muscles of the front upper thigh control the straightening (extension) of the lower leg in relation to the upper leg by increasing the angle. The sartorius muscle is also involved. The three hamstrings at the back of the upper thigh do likewise but in the reverse way by decreasing the angle (flexion): the lower leg is raised towards the thigh. The two abductors at the side of the hip move the leg outwards and three adductor muscles of the inner thigh bring the leg back in towards the centre. Two hip flexor muscles raise the upper leg towards the pelvis and the hip extensor straightens the leg in relation to the pelvis.

Obliques down the side of the trunk allow lateral (sideways) movement relative to the lower body and although the several serratus anterior muscles are small, they are important and pull the shoulder down towards the pelvis. They are involved with twisting movements of the upper body relative to the waist and are tied in with the obliques. The abdominal muscles pull the upper body in line towards the pelvis.

It is important to realise that reducing the angle between the trunk and the top of the thigh as in sit-ups actually uses the hip flexor muscles which connect the lower spine and pelvis to the top of the upper thigh bone. Too many sit-ups can cause low back pain. You should roll forwards by leading with you head and MUST NOT keep your back straight to really hit the abs - to no more than 45° angle.

Negative Isotonic Contraction

Soreness is generally accepted as being a result of negative isotonic contractions especially by placing a great load upon the muscle causing damage to connective tissue. If the load is greater than can be moved positively then the strain upon the muscle is more likely to cause discomfort. The reason that this type of work is done is that it promotes strength gains and muscle fibre recruitment is implicated again. A good picture to keep in mind is of an elastic band but held under some tension. This corresponds to the normal resting state for a limb at the current (training). If the limb is extended beyond the normal limit for range of motion (stretched) then the tension increases until the limb can be moved no further. Shortening the muscle by flexion will cause the tension in the connective tissue to be reduced as its elastic nature allows it to take up the slack - the connective tissue spans a shorter distance. In the positive concentric movement an increasing number of muscle fibres become involved in moving the load and this ensures sufficient contractile force is generated up to the maximum possible, again for the current state of training. This is the type of work to increase the neuromuscular efficiency and hence strength gains.

The muscle working in this eccentric phase (negative contraction) is still the prime mover. Initially the mechanism involves selectively switching off muscle fibres to reduce the contractile force. When alpha-motorneurons stimulate muscle fibres, the fibres contract in an "all or nothing" fashion. Some fibres may become fatigued during the slow movement and others are recruited to sustain the contractile power. This recruitment explains why negative contractions promote strength gains. This reduction in force reaches a point where there are no longer sufficient fibres to overcome the load and the muscle extends, pulled down by gravity acting on the load. The tension within the muscle and the surrounding connective tissue begins to rise as the muscle lengthens. Under normal circumstances, a load which has been moved in the positive phase is the same which is moved in the negative phase. Fibres still participating in the contractile mode are attempting, and failing, to resist the load and they become overloaded. Contraction is in the opposite direction to the movement of the limb as the muscle lengthens.

The tension in the connective tissue in the contracting fibres is increased because a greater number of fibres are not participating and the connective tissue around these fibres is pulling in the opposite direction. The stress receptors, Golgi organs in tendons and muscle spindles within muscle, monitor this rising tension and inhibit the alpha-motorneurons, those responsible for contraction. The muscle contracts less strongly and continues to lengthen. The antagonist muscle becomes increasingly involved to control the limb as the alpha-motorneurons are inhibited. Remember the agonisVantagonist muscles work together and in the positive phase as the agonist contracts the antagonist is inhibited. The reverse occurs in the negative phase - the agonist contraction is reduced in intensity so the inhibition of the antagonist is similarly reduced.

The tension reached depends on the load used. The greatest stress possible is to use a load which cannot be moved positively at all and this is where most of the problems, and strength gains, occur. For example, a press up can normally be performed using the body weight as the load without a problem. If, however, with the arms aimost in the fully extended position (elbows not locked out), a heavy weight was placed upon your back - just too much that a press up to this position would not be possible - then the triceps and chest would not have sufficient strength to stay in this position and the elbows would begin to bend. Gravity is pulling you down and a slow downward movement would occur in the negative contraction of the triceps. The point is that you do not have enough strength to stop it completely but can resist and slow it down if the weight is correct. At the full range of motion the antagonist will become the prime mover as you attempt to stretch the muscle beyond its normal range. The roles reverse. It is at this point where the tension receptors adjust the stress by initiating contraction against the stretch and inhibit the contraction of the muscle causing the stretch beyond the limit of the range of motion. To a large extent this is where training can overcome the amount of reflexive resistance against the stretch and allow further lengthening of the muscle. If a load is used especially in a negative contraction exercise where this load is too much to move positively then great care is needed. Injury could occur.

Partners in Stretching

The practise of using partners to assist in stretching is not a safe one and should be discouraged. When stretching to the maximal length of a muscle the muscle is at it most vulnerable. Forcing more length too fast or too far can have catastrophic consequences. By the time a partner can be told to stop it is probably already too late. At best a well trained stretching partner who is constantly seeking information about the feel of a stretch may be useful. But the practise is still dangerous. Get used to stretching without assistance.

Speed Conditioning

The concept of speed conditioning against reflex control to limit movement must be considered. When applied to the destruction (breaking) techniques in Taekwon-Do, full speed at the moment of impact requires a well stretched muscle in order to ensure the limb is not compromised by misalignment. This applies to the arm or leg. If the limb is not straight a loss of power will occur.

Even a properly stretched muscle that has not been speed conditioned will never reach full velocity at maximum length. The reason for this is that the Golgi organs (stretch receptors) in muscle spindles within the muscle will tell the nervous reflex system to restrict the speed of the limb if it is too great near to its maximum length. This is a biologically in built safety mechanism to prevent damage. Speed conditioning resets this very mechanism to allow the full velocity to be reached at (very nearly) the full length of a muscle. What this means is that if stretching of the muscles is not achieved then neither will the full potential ever be reached in terms of the power/speed relationship (P=1/2mv2).

Suggested Movements

The following is a suggested session sequence with the assumption that it does not involve any other sport specific training. It is not to be regarded as rigid and fixed but purely to illustrate the type of work that should be involved in stretching.

Begin with a general warm up. Dynamic leg exercises would suffice. Star jumps, stride jumps and jump leg crossing are all related. They are not ballistic since the muscles are not at full length. They are, however, similar to isometric type stretches but held only momentarily before pushing off vigorously. It is explosive muscular work.

Star jumps use contractions of the abductors to take the legs outwards and stretch the adductor muscles. The adductors are then contracted forcefully to return the legs to the centre. Stride jumps if used at a good length work the hamstrings quite hard and the hip flexors and hip extensors which control the amount of movement of the legs forwards and backwards. Jump leg-crossing from side to side involves the sartorious muscle as well as contractions of the adductors which are more forceful and greater range of movement than with standard star jumps.

Move on to front leg raising exercise, but make sure you do it correctly with the knee locked out and forward, upward and outward. Without the outward motion then the adductors are not implicated. It is these very muscles that the exercise is designed to work and stretch. The natural tendency is for the leg to move inwards as that is exactly what the adductor muscles do. The stretch is against this natural tendency. The abductors on the standing leg contract and pull the pelvis level. If this did not happen then the foot could not clear the ground as the pelvis would drop. Move straight on to leg swings both inwards and outwards making sure you reach the full range of motion expected.

You can now do some isometric stretches if no other training session is planned and will probably involve side and front splits. Use your body weight to load the muscles and when at full stretch hold this position for 3 seconds. Use an isometric contraction of the stretched muscle and hold for another 3 seconds then adjust the physical length of the stretch, hold for 3 seconds and then contract for 3 seconds. Adjust and repeat. When you have reached your absolute maximum stretch distance, hold and contract for anything between 15-30 seconds, the longer the better. You will not be able to properly or safely train later this day. However, be assured that not only will the stretch be successful, but also the muscle strength will be increased.

The last phase of stretching should involve relaxed static passive stretching. This type of stretching does not provide such dramatic results as the isometric stretching, but can be done at any time and as often as you like. It is an acquired skill to be able to do these stretches successfully. Nearly always, untrained people will have many muscles in a state of tension where none should be. It really is essential to mentally review the status of a given muscle and be knowledgeable enough to know whether it should be relaxed or tensed. This comes with time and training. Emotional states interfere with muscle tonus and yogi use stretching as an indicator to mental relaxation. If anxious then relaxation is very difficult, if at all, possible.

It is interesting to note that no muscles or ligaments or tendons connect the left leg to the right leg. When sitting down with one leg to the front the other leg can be quite easily placed in a side split (perpendicular) position. The legs can be switched around also without any problem. But to place both legs into the side split position is next to impossible because involuntary contraction of the adductor muscles prevents this situation occurring. Imagine walking along the street without this reflexive control. Well, you wouldn't be able to walk - your legs would splay outward into the splits! This is the sort of conscious control you need to be able to use in order to relax muscles at will. You will still be able to walk correctly but you will also be able to do the splits.

So, the type of stretches will involve side and front splits but taking the body weight onto the arms so ensuring no loading is placed upon the leg/hip muscles. This would be an isometric stretch. Sitting down with both legs spread out and taking the chin down to the knee alternating left/right. In the same position the trunk can be stretched (obliques) by placing the arms behind the neck and taking the elbow directly down to one then the other side. Holding the position changes the passive stretch into an active stretch by contracting one muscle while relaxing the other. This contraction is isometric.

Be clear about the difference between an isometric stretch and isometric contraction. They are totally opposite in meaning in that the contraction shortens the muscle and the stretch is contracted, but at full or nearly full length. The soles of the feet placed together and pulled up into the groin ensures that the adductors and abductors are going to be worked. But only properly if the abductors do the work. Use a forced muscle contraction to pull the knees down and so relax the adductors. This is a classic case of an active static stretch using an isometric contraction to perform. If the elbows are used to push the knees down then the stretching potential is ruined.

Rolling onto the back with one leg placed over the shoulder and the other kept with the back of the knee in contact with the floor allows the greatest angle between the legs to be achieved. This is almost identical to the front split position but with no body weight and consequently not isometric. The same can be said for when the legs are both taken out to the side. It is an inverted side split position without body weight. Much care is needed with all passive stretches to ensure that no tension is introduced. When you can relax a muscle properly it will "creep" out to a better length. The key to stretching is to establish the new length as the natural resting length. In the full version I go into great detail as to how muscle stretches and contracts and the reasons for tension. For now you must accept that the contractile proteins within muscle move essentially without friction and generate no tension in so doing. Stretching connective tissue protein causes tension.

Do not neglect the shoulders and the musculature in that area. There are several muscles holding the humerus up in the shoulder since there is no ball and socket joint like in the hip. This is the reason why shoulder dislocation (subluxation) happens relatively easily. Several muscles are involved also in moving the arm forward or backwards and elevating the arm up or moving down. The whole set is involved in rotation around the shoulder joint. Flexibility is necessary in this area for fast movement may also involve the middle back region and chest (punching). Experiment with movement in different directions. If it is uncomfortable then work on this movement. Increase the range of movement. It will make you a more efficient human machine.

Mechanics and Analysis

To produce the correct technique in kicking it is important to watch your foot and whole leg movement. Corrections to poor technique may be possible by stretching particular muscles. Remember if certain muscles are tight or shorter than others then it may be impossible or hazardous to perform some kicks correctly.

It is not enough to just know how a kick is executed, you must also have the right muscle length and strength to do it properly and without injury.

The following two examples are only described to illustrate the type of thinking used to examine any kicking technique.

Axe Kick

Consider an axe kick. Short hamstring muscles and the hip extensors (antagonists to hip flexors) at the maximum height of the kick become very taut (prestretched) but are not involved in getting the leg to the raised position, the hip flexors do this. The gluteus medius and gluteus minimus are the two main muscles involved in the upward movement controlling the abduction of the leg if an outward kick or the adductors if inwards across the body. The leg is taken up by the hip flexors (iliacus and psoas major) working in conjunction with this inward or outward direction. The sartorius muscle is used in the inward axe kick (in/up) with more involvement towards the top of the movement. This can result in an uncontrolled hamstring/gluteus maximus muscle group contraction from the prestretched state for the downward movement. The hamstring should not be involved but is involved because it has been prestretched. The axe kick is executed with excessive force and potentially serious injury could be caused simply through a lack of stretching of the hamstrings. In the sparring point scoring axe kick, partial knee flexion can involve the hamstring. A sudden forceful contraction of the hip flexors to stop the downward movement of the axe kick could cause damage if the muscles are not strong. The leg momentum generated in full flight will need considerable power in these muscles to stop a kick. Tight leg muscles (hamstrings and/or hip extensors) can easily be detected by attempting to lift someone's leg in the front leg raise. Considerable downward force is exerted against the upward push. A well stretched person has a leg which offers little resistance to the upward movement. Such a leg is easily held aloft.

Turning Kick

Well stretched leg muscles without sufficient strength can also lead to excessive and uncontrolled techniques. A turning kick may appear to be executed correctly. The hip abductors and flexors are implicated in the initial movement to raise the leg to the side and upward while the adductors are relaxed. The next phase of the kick is inwards again using the hip flexors but now beginning to use a quadriceps muscle group contraction to straighten the leg. If hip flexor strength is poor the leg motion cannot be arrested and the kick is effectively uncontrolled due to the initial inertia and the subsequent momentum generated being too great. Muscular strength in this instance can be used to slow the leg quickly for control or accelerate if necessary for maximum force. A sudden forceful contraction of the hip extensors (gluteus maximus) to arrest the motion of a turning kick in its last phase could cause damage if the muscles are not strong. The leg momentum generated in full flight will need considerable power in these muscles to stop a kick. Conversely, lack of flexibility in some areas around the hip will impair the execution of a turning kick. Sometimes the combination of muscles will affect the kick. The hip abductors (glutei medius/minimus) may be strong enough to raise the leg in an outwardly direction but as the kick moves forward as a result of the hip flexors (iliopsoas) operating any inflexibility in the hip extensor (gluteus maximus) will prevent a smooth transfer of movement. Nearly all kicks require the partial transfer or involvement of other muscles as the technique develops.

Methods of Stretching

Generally, all types of training should be preceded by dynamic stretching and ended with static passive stretching. Static active involves isometric contractions so should be regarded much in the same way as isometric stretching . Any isometric stretching is physically demanding and at least 24-36 hours should be left for full recovery. Passive stretching may be done during this period. When muscles get tired they are easier to stretch passively but you should not perform dynamic type exercises. The brain remembers the activity that is performed most frequently. If too many dynamic exercises are done when the range of movement is becoming worse through fatigue these are the ones most likely to be remembered. Only do enough dynamic exercises to reach and maintain the full range of a limb. The nervous regulation of muscle does not allow lengthening that is too rapid towards full range of the limb. This is an in built protection mechanism to prevent tears. What needs to be done is to overcome this mechanism to allow, for instance, a fast front kick to the full extent of travel If training does not do this then the moment that full speed is needed at nearly full range the muscle will begin to contract and slow down. You will never be able to reach your full potential.

The front leg raise and inward/outward circular leg swings are dynamic exercises. It is crucial that the full range of movement is reached and maintained. Anything less than absolute full range is not worthwhile. You will just get tired without improvement. Any kick performed correctly is a dynamic exercise be it an axe kick, side kick, turning kick etc. It is essential to watch your leg and foot to ensure that the direction is correct. Learning a technique with untrained limbs will produce errors unless corrected. Remember what feels right for the current training condition maybe without stretched muscles. The muscles necessary to perform kicks correctly need stretching. You cannot expect good technique with poorly trained muscles. There are special receptor cells within joints that inform the brain of position of a limb. This mechanism allows us to know when something is right but only when it has been learned in the correct way. Obviously many people 'feel' something is right when in fact the technique is wrong. It is simply what has been learned. The visual feedback can allow corrections to be made. It also becomes apparent by pain when muscles need particular and specific attention. Knowledge of the body musculature and conscious sensation is the kinesthenic sense by which you will learn a lot about yourself.

Begin with dynamic exercises such as leg raise (ap cha olligi), front kick and inward/outward circular leg swings. These can be done in 4-5 sets and 8-10 reps in each set but gradually increasing the amplitude of movement and switching legs after each rep or set. These should be done two to three times daily for the best results but only a number which allows you to perform full range movements. Experimentation has shown that 30 reps every day twice daily over 5 consecutive days had twice the gains of the same numbers but every other day (10 day period). Eight to ten weeks should be enough to achieve significant muscle elasticity improvements. As range of movement decreases then stop - only do your maximum for full range movements. Early morning is a good time to do this but without "throwing" the leg up. Use "lifting" or "leading" movements but under full control for the entire movement over its range. Leg movements also include raises to the front and side and kicking to the hand as a target to improve (explosive) speed at full range. This is the speed training for full range movements to overcome the reflexive muscle protection mechanism that slows a muscle stretch if the muscle spindle detects a movement which is too rapid. The side leg raise can be with the trunk turned towards the side which also stretches the standing leg adductors or abduction of the raised leg to the side with the trunk fully facing the front. Essentially the same muscles are stretched but from a different angle. Remember this is an important element in stretching as much as in strengthening. Leg raise to the rear knee bent or straight since the hip flexors and extensors are involved not the quadriceps or hamstrings. You should develop your kinesthenic sense generally to feel the muscle involvement and the stretch, in this case, at the front of the thigh.

Stretching of the trunk must not be neglected. Twisting and bending and rotating movements with large amplitude are possible safely only if supple. The joints in the spinal column can be made more flexible with 25-30 reps of an appropriate exercise. Standing or sitting position can both be done but sitting better to isolate the trunk and avoid ballistic movements. Move trunk from side to side keeping legs and hips immobile. Side bends from standing or seated position but not leaning forward - hands clasped behind neck. Forward bends (seated) without straight back or else the hamstrings are stretched (this is a different exercise). Back bend (hyperflex) from stomach and raise trunk upwards using arm and back muscles. If you are training in the same day then do not do any isometric exercises beforehand or you will not be able to train properly. You can do them towards the end of the session but before passive stretching. Isometrics done correctly really are extremely tiring very and should be regarded much in the same way as weight resistance training. You cannot train the same muscles every day. Full recovery is needed.

If you are not training then begin your routine with those stretches that need most work. Front splits (leg in front/behind) and side splits (legs to each side). If your legs are not well stretched then these stretches become isometric unless you take your body weight onto your arms. Be careful not to do isometric type stretches early on in the session unless you are doing nothing else. Isometric stretching is the fastest method of stretching but should not be done at the beginning of a session. Do them towards the end of the training session and prior to relaxed passive stretching at the end and used as a warm down.

Static active stretches will promote strength and involve isometric contractions. For example, the front kick position but held unassisted except by the strength of the quadriceps muscles to extend the knee and hip flexors to raise the upper thigh (femur). The hamstrings and hip extensors are automatically relaxed or should be although you will almost certainly feel tension in them. Training will improve the ability to relax muscles at will but only if you realise that they are not involved in a particular activity. When seated with the soles of the feet together do not use your elbows to push your knees down. Use a forceful contraction of the abductors to pull your legs down. The adductors will be relaxed more by what is known as reciprocal inhibition. What this means is that usually muscle groups work in pairs like the biceps/triceps. Abductors work with adductors and quadriceps with hamstrings. Without this contraction of one and the relaxation of the other then limbs will not move.

Ballistic Stretching

Ballistic stretching involves body or limb momentum to forcibly increase the range of motion of a muscle. This can be quite dangerous. There are only a couple of instances where something approaching this type of stretching is used. In the front splits a gentle up and down movement may be useful but isometric stretching is probably a better method. Stride jumps are partially ballistic but the springing movement as the legs are alternated is far from full length of the hamstrings. A true ballistic stretch would be to slip directly down into the front split position with little or no control and bounce back up. Definitely not recommended unless extremely flexible. Ballistic stretching is probably more useful for very flexible people who need to increase range but for whom other methods bring no further results. Ballistic stretching is still dangerous, however, and at this level of flexibility unlikely to produce any useful gains.

Isometric Stretching

Muscle without tonus (tension) has essentially no restriction to movement. Muscle is comprised of lengths of fibres all aligned in a particular direction but with no actual connection between them. The contractile mechanism is initiated by impulses from the brain which alters the calcium ion flow to the interfilament parts and starts a process by which the fibres "stick" to each other. Without any nervous trigger to begin contractions between the two major proteins actin and myosin there is no contraction. There is no tension. Relaxed muscle with much reduced tonus is relatively easy to lengthen. Muscle under tension is difficult to lengthen because of this interaction. Certainly beyond the current untrained length. The difference between sliding out the top plank of wood from a pile or trying to pull off the plank if it is nailed to the one beneath. These could not be separated. However, muscle is wrapped up in connective tissue - the outer covering of muscle fibres. The component to lengthen is this connective tissue. It has no ability to contract itself but offers considerable resistance. It is like comparing elastic and string. Elastic can be deformed by lengthening but will return to its original length. String will simply get to a particular length and not get any longer without snapping.

The connective tissue will be stretched if the range of movement of a limb is increased. An alternative way of approaching this is to keep the limb at a particular angle (and so muscle length) and then aHempt to shorten the muscle and hence the surrounding connective tissue. The muscle can shorten a liHle by a powerful contraction. The tension generated can be enormous. But since the limb cannot move the connective tissue has to lengthen a liHle as the distance between the ends of the limb remains constant but the muscle length is expected to shorten by the same amount. The result is that the connective tissue itself is put under stretch.

So this isometric stretching process lengthens the connective tissue which is a very limiting factor to muscle elongation. However relaxed the muscle may be, the connective tissue - which cannot be relaxed as there is no possibility of contraction within it - will restrict muscle length. If the connective tissue is lengthened AND the mental control adjusted to overcome physiological damage protection mechanisms then potential is increased dramatically.

Isometric stretching is the most effective stretches of them all. Isometric stretching is actually the reverse of static stretching. Static stretching requires a relaxed muscle lengthened but kept under continuous stretch at the limit of range movement. This keeps the connective tissue under tension but allows the brain to register the new length for future reference. Isometric stretching can modify the muscle connective tissue length from just about any position. The limb does not have to be at its maximum range - any position will do. The nature of muscle is that thousands of strands of fibres are all aligned in roughly the same direction. A stretch of long duration will allow many of them - if not all - to be placed under tension or a new length. A likely problem is a stretch of short duration does not allow so many to be registered so an unequal data set is learned and the imbalance causes some discomfort. This should be offset by the more controlled long duration static stretch.

Dynamic stretching allows speed adjustments to be made. Developing static passive flexibility, which usually exceeds static active or dynamic flexibility for the same joint, can reduce the incidence of injury. The reserve tensility (flexibility reserve) is greater if the difference between them is greater. Active movements can also be increased in amplitude but the difference between active and passive diminishes as active flexibility improves. Static active or passive stretching performed alone will not necessarily be matched with increases in dynamic flexibility proportional to the increase in the static flexibility. Speed conditioning is dependent on the dynamic exercises to reset the nervous control of muscle spindles. Static flexibility may increase when muscles are fatigued and is the reason for doing them at the end of a workout. Isometric stretching is similar to static stretching but using strong contractions of the fully stretched muscles. This causes reflexive relaxation and a subsequent increase in the length of the muscle because of the involvement the Golgi organs in the tendons and muscle spindle stretch receptors (see full version).

When the maximum length for the muscle has been achieved, at the current stage of training, the position is held for up to 15-30 seconds or more. In a poorly stretched leg a contraction is not necessary in some cases since body weight ensures the muscle is under load, for example in the side splits. In a well stretched leg further gains of length and strength can still be achieved by this additional forced contraction at full length. This method of stretching should be used in a similar way to any strength training - the muscles must be given time to recover. Isometric means one length. The muscle is stretched to its maximum length then a tension is applied. An example of this is the front split where the body is lowered but at the lowest point the muscles are initially relaxed.

This is a static passive stretch. Tension is then gradually applied in the forward leg to contract the hamstrings. The effect of this contraction is to flex the knee which cannot move because of contact of the heel of the foot of this leg with the floor.

This stretch is isometric. The strength of a muscle can also be increased at different positions of flexion by using isometric contractions. Instead of at full length intermediate positions are held under an isometric stretch. This will produce gains in the strength of the muscle at this position. In the front kick position with the heel of your foot placed over a stationary object to raise the leg to its maximum height, the hamstrings are stretched to the maximum length (static passive) if the knee is kept locked out. If the toes and foot pulled back towards the shin the stretch is emphasised and the calf muscles are also involved. However, this becomes an isometric stretch if tension is now applied in an effort to push the leg downwards and flex the knee. It is effectively the same as the front split for short hamstrings using the body weight under the influence of gravity. This also works the hip extensors with more emphasis if the knee is bent but raised as far upwards as possible.

Isometric stretching is the fastest method to achieve static passive flexibility. At full length muscle fibres contract and connective tissue attached to them is stretched. This is the derivation of tension. Strength gains can be made depending on the force of contraction. Such gains are at the full length of the muscle where it is normally at its most disadvantaged. Stretched muscle is weakened by virtue of the increased length of the sarcomere. The overlap between the protein filaments is reduced resulting in a loss of contractile force. Isometric stretching helps to restore this loss. Review the Section 2 on muscle contraction. When a muscle normally contracts and moves two bones together the connective tissue tension is reduced - the muscle shortens. In the isometric stretch at the full length of the muscle, the connective tissue is placed under greater than normal tension as the muscle is slightly longer than at rest. A forceful contraction but without moving the limbs the muscle will attempt to shorten but is not allowed to so that the tension will build up. Remember that isometric stretching is very demanding on muscle and sufficient rest time, at least one full day (24-36 hrs), should be allowed between sessions for the muscle to recover completely.



Perform isometric stretches by gradually stretching the muscles and allow them to "creep" to the normal full length without using contractions. After a few seconds, from this position increase the stretch. Maintain the position then increase the distance further. When at the maximum limit of stretch, apply the short strong tensions built up over 2-3 seconds and hold for another 2-3 seconds at the maximum tension. Do the isometric tensioning 3-5 times but on the final one hold for 30 seconds at the maximum. A similar method is to use tension at each position of the stretch as it is increased each time holding for several seconds as before. The final tension is done just once but for 30 seconds at the maximum muscle length. A more severe method of isometric stretching involves reaching the maximum muscle length and tensioning. Hold this tensed stretched position until the muscle spasms then relax the stretch. After a brief pause repeat at full length and maximum tension until the muscle spasms again. Do this for 3-5 times holding the last tension for as long as possible - maybe several minutes. This will make you want to scream! Whichever method you use strength gains will be achieved at that muscle length.

To counter the loss of tension by lengthening a muscle the ideal position to improve the strength is at full length to restore this loss. Concentrate on harder and longer contractions at full muscle length. Use weight if necessary but in any case attempt to modify the style by increasing the difficulty - for example do not use hands in splits. To stretch isometrically too often and too powerfully will not allow the muscle time to recover. The only way to increase the frequency of isometric stretching sessions would be to reduce the maximum tension considerably but little in the way of strength gains would be achieved. However, it may be sensible to train in this way to begin with while the muscle develops conditioning. It depends on what you want from stretching but remember that the stronger the muscle is then the more stability it offers joints and protection from injuries.

Strength gains through isometric stretching will reach a plateau after a few weeks since the same load is placed on the muscle, no further muscle fibre recruitment occurs. Further gains will need weight resistance training to place a greater load on the muscle. The combination of isometric stretching and use of weight (either isotonically or isometrically applied) is ideal. The weight of the body can be utilised also by, for example, sliding up or walking up from a splits position. A strong and flexible muscle will result. Remember that at the full range of motion for a muscle, and stretching by definition means at its longest, the muscle will remain flexible as the strength improves. The contractile elements of muscle have almost no friction when under no tension and properly stretched connective tissue reduces the build up of tension as the muscle is lengthened. If muscle soreness is experienced then either reduce the intensity of stretches or leave off the isometric stretching completely until this soreness has disappeared - usually only a day or so extra. Passive relaxed stretching can replace the isometric stretching during such times to maintain good muscle condition. Ensure that isometric exercises are preceded by dynamic exercises but can be followed by relaxed passive stretching to finish. Reintroduce the isometric stretches when discomfort has cleared. There is nothing to be gained by stretching an injured muscle.

The soreness is as a result of overloading the tendon and connective tissue and is the same as for a negative isotonic contraction. The entire muscle structure has done greater work than it is prepared for so the loading on these tissues will be damaging. Until the connective tissue has itself lengthened through stretching then the damage to this collagen material will occur. Reduce the intensity of isometric contractions at full muscle length until the connective tissues have progressively adjusted. If the muscle strength increases and muscle fibre recruitment continues through stimulation either by isometric stretching or weight resistance work then the problem can worsen and lead to long term (chronic) injury. The connective tissue must be given time to lengthen and thus reduce the excess tension build up within the tendon. To some extent the Golgi organs will protect the tendon and connective tissue by not allowing too powerful contractions (discuss Renshaw cells) but pain is a sign to stop. Already alluded to is the danger of anabolic steroid abuse and the potential serious damage to tendons by artificially promoting muscle mass gains which outstrip the changes to connective tissue. This imbalance of growth leads to the destruction of muscle integrity and torn muscles and tendons.

Stretched (and weakened) muscle is fine for the increase in the range of motion and may allow more control of limbs by avoiding prestretching muscle - winding them up by throwing up a limb rather than controlled lifting. Prestretching involves the elastic nature of connective tissue and pulling it to greater length. No change in the structure of connective tissue occurs just its temporary length increase under load. A powerful muscle is also fine and allows greater control over limbs by increasing the ability to lift, raise and decelerate as opposed to the use of momentum by "throwing" a limb. In the absence of stretching, prestretching is still a problem. A more powerful muscle will allow a greater prestretch of the connective tissue to occur and create more force but which is harder to control. Golgi organs will reduce the likelihood of an overload injury if the prestretching is too great by relaxing the muscle but such injuries can occur. In power gains without stretching, the range of motion instead of being increased will actually be decreased. The reason the muscle shortens if not stretched is that the muscle enlarges and in effect swells out in size with little modification to the connective tissue length. The balance of power can be maintained by training agonist and antagonist but without stretching, the range of movement of the limb they control will be compromised. Stretching both muscles will make them more efficient and improve this range of motion. To compensate for the increase in size of muscle fibres but not the length of the connective tissue, the tension regulation mechanisms (Golgi organs and gamma-motorneurons in the muscle spindles) will restore the normal resting tonus (internal tension) by shortening the muscle. To maintain or increase the range of motion the whole muscle, including the connective tissues, must be lengthened.

This is not the same as the lowered tonus during sleep causing the muscle length to be shortened to counter the decrease in the nerve impulses from the stretch receptors of "super relaxed" muscle. A loss of tension allows an increase in these contraction impulses which also inhibit contractions of the antagonist muscle (reciprocal inhibition). Under these conditions the agonist muscle can shorten quite easily with little resistance from the antagonist. In the reverse sense, increases in tension are countered by the tendency to inhibit alpha-motorneurons, which cause contraction, facilitating antagonist contraction. Under normal conscious conditions the increased general tonus restores the normal range of motion by this antagonist contraction to pull out the agonist muscle to a slightly greater length (the waking stretch response). Tension arises from connective tissue in resting muscle. The elastic nature of this tissue allows it to take up the slack if tonus is lost. The whole point about permanent stretching is resetting the normal nervous resting tension.