The objective of stretching is, of course, to improve one's flexibility (see Note 1). Flexibility is the ability to move muscles and joints through their full range-of-motion (ROM). ROM is determined by the type of joint e.g., ball-and-socket, as in shoulders; or hinge, as in elbows and knees). Each of us is born with some built-in flexibility determined by the natural structure of each joint; and the direction of movement at a joint is dependent on that joint structure, as well as muscle and tendon attachment points.

Everyone has their own unique ROMs for each joint, but with one common characteristic: any Rom can be reduced by injury, disuse, or disease; or, in most cases, improved by use of a variety of stretching techniques.

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Note 1 - As you will remember, the four componennts of fitness are: 1) muscle strength and endurance, 2) cardiovascular/cardiopulmonary endurance, 3) body composition, and 4) flexibility.
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Importance of Flexibility

There are a number of reasons to stretch - to improve flexibility as part of a warm-up for sports activities, for relaxation, after sets while weight training - do what seems beneficial to you and your specific goals. It is thought by many that flexibility may help prevent injuries. The theory being that lack of flexibility may result in muscle or tendon tears, pulls, - various stress injuries; as well as impaired functionality. A full ROM is important to everyone for athletic pursuits, normal activities, and even to maintain good posture. In addition to a full ROM, it is also important to maintain balanced flexibility, for all the same reasons - both can help prevent muscle soreness, headaches, dizziness, fatigue, and more.

Stretching Duration

Stretch to the point of being slightly uncomfortable, but short of pain. Hold for 10-20 seconds; relax; repeat 3-5 times. Each succeeding repetition should achieve a slightly deeper stretch. But once you reach your goal, be aware that you can't stop stretching, and still maintain your level of flexibility. This must be a lifestyle commitment. Note that the time that a stretch should be held is not universally agreed on. Some say ten seconds, others say 20 seconds, but there are an infinite variety of durations proposed, including one that I recently read somewhere that suggested three or four two-second stretches. Try them out and see what you like.

How Often ?

To increase your ROM, start a stretching program that you do 3-7 days per week. The more the better. Three times a week should be sufficient for maintaining current ROM.

Immediate Stretching Benefits

• relaxation - relieves tension

• alleviates pain (e.g., hamstring stretching may relieve low back pain)

• may reduce or relieve delayed onset muscle soreness (DOMS)

Note that aging and flexibility are not incompatible. The elderly can, and should, continue stretching. This is one of those lifelong habits that each of us should adopt.

Also note that flexibility is joint-specific, so there is no single flexibility test. There can be differences in flexibility in different muscle groups/joints, including bilateral differences in the same joints. It is beneficial to concentrate on inflexible but frequently used joints/muscle groups. But that doesn't mean to ignore the other areas.

Contraindicated Stretches

• Toe touching - This stretch for the lower back and hamstrings is on the list because actually touching one's toes is not the real goal, but many people treat it that way; like they get a prize for touching their toes, even if it means injuring themselves to do it. People often hump their backs and overstretch, risking hamstring and/or low back injuries. See page 4 for a proper hamstring stretch.

• The "plow" - This yoga stretch puts excessive stress on the neck, and should be avoided. If you don't know what it is, that's good. And I'm not going to tell you.

• Ballistic - This is a stretching technique where you bounce to increase your stretch; for example, while doing a hamstring stretch, it is not uncommon for someone to achieve a maximum ROM and then do a series of bouncing movements to increase the stretch. But that technique can cause muscle or tendon injuries. It triggers the "stretch reflex," which is a resistance in the form of a "pull" in the opposite direction. This is a mechanism used by the body to help prevent overstretching damage.

• Barre bar - This is a bar used by dancers to stretch hamstrings, but for fitness stretching the barre bar is typically mounted too high and puts one at risk for a low back injury. See page 4 for an approved hamstring stretch.

• Hurdler's stretch - This is another hamstring stretch which can do more damage than good. It should only be done by very flexible athletes. See page 4.

• Circular neck stretch (360 degree) - This stretch, which requires rotating one's head from side-to-front-to-side-to-rear, over-and-over, and in both directions, was taught eons ago when I was in high school, a few centuries ago. It has since been found to potentially cause back-of-the-neck injuries. This can be done as a 180 degree movement (side-front-side), but see page 6 for a preferred alternative.

The process of increasing flexibility uses the principle of progressive overload, just as with muscle strengthening. You stretch to your current ROM, and progressively increase it. Immediate results will not be seen, but after a week or so, you will likely see them - it takes time and consistency.

Stretching Techniques

There are several methods of stretching; four of which will be discussed: 1) static (both assisted and unassisted), 2) ballistic, 3) active stretching, and 4) PNF.

1- Static Stretching is the preferred method (preferred by me, especially for beginners), although the others have their proponents. As the name implies, there is no movement during this type of stretching; however, it is often done specifically to improve flexibility, and does, therefore, include movement , but in stages, not continuous. That is, one positions for a specific stretch, holds it for about 10 seconds, then stretches a bit farther, and holds again. Three 10 second stretch-hold sequences should be sufficient. Maybe only one in some cases.

Static stretching may be done with a partner, who will help by pushing/pulling (gently) limbs into position, and holding a constant tension. The assistant helps one through the stretch-hold sequence. Note that this technique can be very effective, but there must be good communication to prevent an over-enthusiastic partner from injuring the "stretchee." A basic static stretch program follows.

Basic Stretching Program

Always start with the Elongation Stretch: performed in a supine position with arms and legs stretched in both directions, as far as they'll go. Fingers and toes are pointed out, palms are facing up, legs are together, and the hip girdle should be slightly tilted toward the floor, to maintain the slight inward curve of the lower back. Basically, you are trying to separate your legs from your trunk (well, not really, but you get the idea). Be sure to breathe slowly and deeply. Three repetitions of 10 seconds each is sufficient. Note that it is perfectly acceptable to use a wall or a chair for support whenever you need it. Lack of stable balance during a stretch diminishes its effectiveness. Now proceed with stretching specific body parts as follows:

• Hamstrings - An effective stretch is the "modified hurdler's stretch" as shown in Figure 8-1, pg. 9. An effective alternative is done by standing on one foot, with the other foot resting on a step, chair, bench, or whatever. The point of contact for the elevated foot is the heel, and the leg is straight. Bend forward from the hips with the back "flat." Bend forward until you feel an uncomfortable, but painless, tightness in the hamstrings. Another alternative is to lie on your back with one leg extended, and the other leg bent at the knee (to relieve low back tension). All of these stretches may be assisted by looping a towel under your foot to provide the appropriate constant tension (see Figures 8-1a and 1b, pg. 9).

• Buttocks - In a seated position, perform this stretch as shown in Figure 8-2, pg. 9.

• Lower Back - In a hands-and-knees position, do the "cat" stretch as shown in Figure 8-3, pg. 9. The point here is to arch your back by "rolling" it up vertebra-byvertebra. Pause, then "unroll" it.

• Inner Thighs - Sit with knees bent and spread as wide as possible. Soles of the feet are touching. Gently press down on your knees with your hands or elbows (see Figure 8-4, pg. 9). This can alternatively be done against a wall, back on the floor You can also pull your feet toward you to add intensity to the stretch.

• Quadriceps/Hip Flexors - Perform this stretch as shown in Figure 8-5, pg. 9, but note that it is easier for many people to do this in a standing position. It is important to note that, as the foot is being pulled up and straight back, there is a simultaneous attempt to straighten the knee; in other words, the quads are being held in a state of constant tension. Keep the thighs in their normal position - vertical.

• Calves - Our calves consist of two muscles: the gastrocnemius, which is what you see; and the soleus, which is just beneath the gastrocnemius (i.e., deeper). Do the stretch shown in Figure 8-6, pg. 9. Note that when the knees are straight, the gastroc-nemius muscle is stretched. If the knees are slightly bent, the soleus gets the main stretch. This happens because the gastrocnemius is a two-joint muscle (knee and ankle), and is strongest in the straight position. The soleus, a one-joint muscle (ankle only), is strongest when the knee is bent.

• Shoulders - Two effective shoulder stretches are: 1) in either a seated or standing position, reach as high overhead as you can; and at the same time, with your other arm, reach down as far as you can. Repeat in the opposite position; and 2) with one arm extended forward from your shoulder, grasp the elbow with your other hand, and gently pull it across your chest (see Figure 8-7, pg. 9). Note that the figure shows the exercise slightly different from the description, but either method is acceptable. Repeat on the other side.

• Triceps - See Figure 8-8, pg. 10.

• Biceps - With both arms fully extended, and angled behind you - hands are roughly at hip level and about six inches away; bend your wrists so your palms are facing behind you. The more you straighten your arms and bend your wrists, the stronger the biceps stretch you will feel. If this isn't clear, just try to extend (straighten) your elbow as much as you can.

• Neck - My favored way to stretch the neck is to not move it at all, but to apply static force against it in all four directions. For the front of your neck, place heels of your hands against your forehead, and press your head against them, but resist any movement. For the sides, place the heels of your hands against the sides of your head just above your ears. Your elbows are pointing out to the sides. Press and resist on each side. For the back of the neck, place your hands against the back of your head, with elbows out. Now push-resist as before. You can, of course, make this press-resist action anywhere in the 360 degree circle around your head.

3-Active Stretching is a technique typically used prior to sports activities, and often after a period of warm-up and static stretching. Examples are: playing "catch" before a baseball game (start easy and increase intensity), doing "shoulder rolls" before exercise, or twisting-swinging movements with a golf club before a round on the links. This technique definitely plays an important role in sports.

Another goal of active stretching is relaxation. Many Yoga stretches, for example, involve slow and controlled movement.

4-Proprioceptive Neuromuscular Facilitation (also called Facilitated Stretching, or more commonly, PNF). PNF is seemingly a very effective technique, and may become the "star" of stretching techniques. The essential difference between this and other forms of stretching is that the muscle to be stretched is first contracted, then relaxed, then moved to a fuller stretch.

In essence, this is static stretching with a "twist." The "twist" is that an assistant holds a limb at its current ROM, and resists a force exerted by the stretcher. Then he/she relaxes, and the assistant moves the limb into a deeper stretch. The initial static contraction is theorized to trigger the muscle's stretch reflex (a component of all muscles it is essentially a pull in the opposite direction to prevent overstretching damage), relaxing the muscle, and, thereby allowing a greater stretch. PNF is used to achieve a quick increase in ROM. Static stretching is used to maintain it. Note that a towel can substitute for an assistant. But don't pull the towel to increase stretch, it is just to provide static resistance. This section on PNF is just an introduction - there are books on the subject, and I'm not going to add to the list; but here is one example of how you can effectively use this technique, without an assistant, or a towel, to stretch hamstrings. Lay on your back in a doorway - close to one side or the other. The leg closest to the frame is extended as far as allowed by the hip's current ROM. The heel is resting against the door jam. Press it against the jam (static contraction). Now relax, and move a little farther through the door so that your hip is flexed to its new ROM. Repeat as you like, but don't go beyond 90 degrees. Remember to work for balanced flexibility.

Stretching for Sports

Stretching is important to virtually all sports. Some require a high degree of overall flexibility (e.g., gymnastics or dance); others require more specific areas of flexibility (e.g., swimming or baseball - rotator cuff).

Flexibility also has ramifications for power. The more a muscle can stretch, the more energy can be released during contraction. It appears that muscles can store elastic energy , and then release it in a forceful movement (e.g., a baseball pitch). Clearly, there are limits - kind of like a point-of-diminishing returns. Once you reach a certain level of flexibility, no further performance can be achieved (based only on flexibility, of course).

It may also be true that good flexibility can prevent some injuries. For instance, inflexible hamstrings may lead to hamstring or knee injuries. Flexibility imbalances may also be a problem. Likewise in-elastic scar tissue resulting from an injury can lead to further inflexibility and further injuries. Stretching might save sports careers by helping to prevent a waterfall of related injuries.

I won't get into specific sport stretches - that is outside of the scope of this Newsletter, but if you are interested in something specific, make a request, and our staff will get back to you.

Figure 8-1   Figure 8-1a

Figure 8-1b   Figure 8-2

Figure 8-3   Figure 8-4

Figure 8-5

Figure 8-6   Figure 8-7

Figure 8-8

QUESTIONS AND ANSWERS

No questions this month. Come on guys, you must have some.

LETTERS TO THE EDITOR

Here is, hopefully, the last word on the hip flexors, a much maligned muscle group. Once-and-for-all, here they are, along with what they do.

1-Iliopsoas - This muscle is strongly involved in raising the legs, while in a supine position. The iliopsoas is actually defined as two separate muscles in many anatomy books, but is treated as one. Its origin in the lower back tends to move the lower back inward (that is, pulls it up) as it raises the legs. This is the reason why lower back pain can result from leg lift exercises. Strong abdominal muscles help to offset this effect. This muscle can be strengthened by high stepping (hip flexion), especially with ankle weights, or by using a multi-hip machine in a gym.

2-Sartorius - This longest muscle in the body (long, but skinny) runs from the outside of the hip girdle, and above the femur socket in the hip, diagonally across the thigh to where it curls below the knee where it anchors on the tibia. This two-jointed muscle which is both a hip and knee flexor, requires the same low back/strong abdominal caution, as above. In other words, work those abs, unless you want a sway back.

3-Tensor Fascia Latae - This muscle runs along the outside of the thigh, and it aids in preventing outward rotation by the femur as it is flexed by other muscles. The main action here is to keep the feet placement straight forward during walking or running.

4-Pectineus - This short muscle, located between the pubic bone in the hip girdle, and the inner part of the upper aspect of the femur. This muscle is exercised along with the iliopsoas in leg raising and lowering.

Note that specific hip flexors have specific functions, and don't necessarily work at the same time. The point is that when you hear a reference to the hip flexor, you now know that there is not a hip flexor.
H. G., Atlanta, Ga

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One response to endurance (aerobic) training is the increased ability to burn fat, as opposed to the other energy sources - carbohydrate and protein.
B. R., Boston, Mass

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A diet of 12%-15% of calories from protein is considered by many to be adequate for most athletes, unless their total energy intake is deficient. Excessive amounts can lead to kidney damage - because of the large demands made on them to process the excess.
G. B., Oakland, CA

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On the subject of loss of strength and speed as we age. It seems that, as we age, we experience a loss of fast twitch muscle fibers - the ones responsible for speed and strength. The result is an increase in the proportion of slow twitch fibers the ones responsible for muscle endurance. One theory says that the ability to innervate ("turn on") fast twitch fibers decreases. Fibers that can't be turned on atrophy and die (actually they are eventually absorbed by the body - sort of an end stage of atrophy).

As we age and lose muscle size and strength, it may be caused largely by a degradation in our nervous system. It can be somewhat offset by athletic pursuits, particularly weight training. Part of the problem is that aging seems to slow down the nervous system's stimulus-response capabilities.
L. F., Beaverton, OR

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Liver glycogen can be depleted after 2 hours of maximal exercise, but is replenished within a few hours when a carbohydrate-rich meal is eaten. Muscle glycogen resynthesis is; however, a slower process, taking several days to return to normal after, for instance, a marathon. Studies in the late 80's revealed that muscle glycogen resynthesis was most rapid when individuals were fed at least 50 g of glucose every 2 hours after the exercise. Eating more had no effect on resynthesis. During the first 2 hours, the rate of resynthesis is 7%-8% per hour, as opposed to a normal 5%-6%. This reinforces what has previously been reported in this newsletter.
D. C., Houston, Tx


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