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Old 05-13-2006, 01:39 PM
EricT EricT is offline
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Section: 3.7.1 How PNF Stretching Works

Remember that during an isometric stretch, when the muscle performing the isometric contraction is relaxed, it retains its ability to stretch beyond its initial maximum length (see Section 3.6.1 [How Isometric Stretching Works]). Well, PNF tries to take immediate advantage of this increased range of motion by immediately subjecting the contracted muscle to a passive stretch.

The isometric contraction of the stretched muscle accomplishes several things:

1. As explained previously (see Section 3.6.1 [How Isometric Stretching Works]), it helps to train the stretch receptors of the muscle spindle to immediately accommodate a greater muscle length.

2. The intense muscle contraction, and the fact that it is maintained for a period of time, serves to fatigue many of the fast-twitch fibers of the contracting muscles (see Section 1.2.2 [Fast and Slow Muscle Fibers]). This makes it harder for the fatigued muscle fibers to contract in resistance to a subsequent stretch (see Section 1.6.2 [The Stretch Reflex]).

3. The tension generated by the contraction activates the golgi tendon organ (see Section 1.6.1 [Proprioceptors]), which inhibits contraction of the muscle via the lengthening reaction (see Section 1.6.3 [The Lengthening Reaction]). Voluntary contraction during a stretch increases tension on the muscle, activating the golgi tendon organs more than the stretch alone. So, when the voluntary contraction is stopped, the muscle is even more inhibited from contracting against a subsequent stretch.
PNF stretching techniques take advantage of the sudden “vulnerability” of the muscle and its increased range of motion by using the period of time immediately following the isometric contraction to train the stretch receptors to get used to this new, increased, range of muscle length. This is what the final passive (or in some cases, dynamic) stretch accomplishes.

Section: 4 How to Stretch

When done properly, stretching can do more than just increase flexibility.
According to M. Alter, benefits of stretching include:
· enhanced physical fitness
· enhanced ability to learn and perform skilled movements
· increased mental and physical relaxation
· enhanced development of body awareness
· reduced risk of injury to joints, muscles, and tendons
· reduced muscular soreness
· reduced muscular tension
· increased suppleness due to stimulation of the production of chemicals which lubricate connective tissues (see Section 1.3 [Connective Tissue])
· reduced severity of painful menstruation (“dysmenorrhea”) in females

Unfortunately, even those who stretch do not always stretch properly and hence do not reap some or all of these benefits. Some of the most common mistakes made when stretching are:
· improper warm-up
· inadequate rest between workouts
· overstretching
· performing the wrong exercises
· performing exercises in the wrong (or sub-optimal) sequence

In this chapter, we will try to show you how to avoid these problems, and others, and present some of the most effective methods for realizing all the benefits of stretching.

Section: 4.1 Warming Up

Stretching is not warming up! It is, however, a very important part of warming up. Warming up is quite literally the process of “warming up” (i.e., raising your core body temperature). A proper warm-up should raise your body temperature by one or two degrees Celsius (1.4 to 2.8 degrees Fahrenheit) and is divided into three phases:
1. general warm-up
2. stretching
3. sport-specific activity

It is very important that you perform the general warm-up before you stretch. It is not a good idea to attempt to stretch before your muscles are warm (something which the general warm-up accomplishes).
Warming up can do more than just loosen stiff muscles; when done properly, it can actually improve performance. On the other hand, an improper warm-up, or no warm-up at all, can greatly increase your risk of injury from engaging in athletic activities.

It is important to note that active stretches and isometric stretches should not be part of your warm-up because they are often counterproductive. The goals of the warm-up are (according to Kurz): “an increased awareness, improved coordination, improved elasticity and contractibility of muscles, and a greater efficiency of the respiratory and cardiovascular systems.” Active stretches and isometric stretches do not help achieve these goals because they are likely to cause the stretched muscles to be too tired to properly perform the athletic activity for which you are preparing your body.

Section: 4.1.1 General Warm-Up

The general warm-up is divided into two parts:
1. joint rotations
2. aerobic activity

These two activities should be performed in the order specified above.

Section: 4.1.1.1 Joint Rotations
The general warm-up should begin with joint-rotations, starting either from your toes and working your way up, or from your fingers and working your way down. This facilitates joint motion by lubricating the entire joint with synovial fluid. Such lubrication permits your joints to function more easily when called upon to participate in your athletic activity. You should perform slow circular movements, both clockwise and counter-clockwise, until the joint seems to move smoothly. You should rotate the following (in the order given, or in the reverse order):
1. fingers and knuckles
2. wrists
3. elbows
4. shoulders
5. neck
6. trunk/waist
7. hips
8. legs
9. knees
10. ankles
11. toes

Section: 4.1.1.2 Aerobic Activity
After you have performed the joint rotations, you should engage in at least five minutes of aerobic activity such as jogging, jumping rope, or any other activity that will cause a similar increase in your cardiovascular output (i.e., get your blood pumping). The purpose of this is to raise your core body temperature and get your blood flowing. Increased blood flow in the muscles improves muscle performance and flexibility and reduces the likelihood of injury.

Section: 4.1.2 Warm-Up Stretching

The stretching phase of your warmup should consist of two parts:
1. static stretching
2. dynamic stretching

It is important that static stretches be performed before any dynamic stretches in your warm-up. Dynamic stretching can often result in overstretching, which damages the muscles (see Section 4.12.3 [Overstretching]). Performing static stretches first will help reduce this risk of injury.

Section: 4.1.2.1 Static Warm-Up Stretching

Once the general warm-up has been completed, the muscles are warmer and more elastic. Immediately following your general warm-up, you should engage in some slow, relaxed, static stretching (see Section 3.5 [Static Stretching]). You should start with your back, followed by your upper body and lower body, stretching your muscles in the following order (see Section 4.8 [Exercise Order]):
1. back
2. sides (external obliques)
3. neck
4. forearms and wrists
5. triceps
6. chest
7. buttocks
8. groin (adductors)
9. thighs (quadriceps and abductors)
10. calves
11. shins
12. hamstrings
13. instep

Some good static stretches for these various muscles may be found in most books about stretching. See Section Appendix A [References on Stretching]. Unfortunately, not everyone has the time to stretch all these muscles before a workout. If you are one such person, you should at least take the time to stretch all the muscles that will be heavily used during your workout.

Section: 4.1.2.2 Dynamic Warm-Up Stretching

Once you have performed your static stretches, you should engage in some light dynamic stretching: leg-raises, and arm-swings in all directions (see Section 3.2 [Dynamic Stretching]). According to Kurz, you should do “as many sets as it takes to reach your maximum range of motion in any given direction”, but do not work your muscles to the point of fatigue. Remember - this is just a warm-up, the real workout comes later.

Some people are surprised to find that dynamic stretching has a place in the warm-up. But think about it: you are “warming up” for a workout that is (usually) going to involve a lot of dynamic activity. It makes sense that you should perform some dynamic exercises to increase your dynamic flexibility.

Section: 4.1.3 Sport-Specific Activity

The last part of your warm-up should be devoted to performing movements that are a “watered-down” version of the movements that you will be performing during your athletic activity. ‘HFLTA’ says that the last phase of a warm-up should consist of the same movements that will be used during the athletic event but at a reduced intensity. Such “sport-specific activity” is beneficial because it improves coordination, balance, strength, and response time, and may reduce the risk of injury.

Section: 4.2 Cooling Down

Stretching is not a legitimate means of cooling down. It is only part of the process. After you have completed your workout, the best way to reduce muscle fatigue and soreness (caused by the production of lactic acid from your maximal or near-maximal muscle exertion) is to perform a light “warm-down”. This warm-down is similar to the second half of your warm-up (but in the reverse order). The warm-down consists of the following phases:
1. sport-specific activity
2. dynamic stretching
3. static stretching

Ideally, you should start your warm-down with about 10-20 minutes of sport-specific activity (perhaps only a little more intense than in your warm-up). In reality however, you may not always have 10-20 minutes to spare at the end of your workout. You should, however, attempt to perform at least 5 minutes of sport-specific activity in this case. The sport-specific activity should immediately be followed by stretching:
First perform some light dynamic stretches until your heart rate slows down to its normal rate, then perform some static stretches. Sport-specific activity, followed by stretching, can reduce cramping, tightening, and soreness in fatigued muscles and will make you feel better.

According to ‘HFLTA’, “light warm-down exercise immediately following maximal exertion is a better way of clearing lactic acid from the blood than complete rest.” Furthermore, if you are still sore the next day, a light warm-up or warm-down is a good way to reduce lingering muscle tightness and soreness even when not performed immediately after a workout. See Section 4.12 [Pain and Discomfort].
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If you act sanctimonious I will just list out your logical fallacies until you get pissed off and spew blasphemous remarks.
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