By Paul Chek, HHP, NMT
Founder, C.H.E.K Institute

Stretching is an ancient form of exercise that goes deeper into evolution than man himself. If you wonder what I mean, watch any cat or dog and you will often see them stretch upon rising after a rest. Birds can often be seen stretching their wing muscles too.

Most ancient martial arts and athlete conditioning systems incorporate stretching as an integral part of athlete development. Stretching has also been part of healing practices for thousands of years. But have we learned anything recently that will improve our results with stretching?

YES, we have.

In this article, I will share the following tips for getting maximum results in minimum time with stretching. You will:

Learn about tonic, phasic and mixed muscle types and which ones should be stretched first
Discover when the best time to stretch is depending on the desired outcome
Learn two basic approaches to lengthening the muscle-tendon unit and which is best for your situation
Realize that as your body, or your activities change, so too must your stretching routine if you want the best results

1. Not all Muscles Are The Same

You are likely to have heard the term "postural muscles" before. This term refers to those muscles ideally suited to hold you up against gravity. The term "tonic muscles" is often used synonymously with the term "postural muscles," yet in actuality, the tonic muscles and postural muscles are somewhat different.

Let me explain: While postural muscles do hold you up against gravity, postural muscles are, for the most part, the muscles on the back of your body, called extensor muscles. Gravity is always trying to push you into the fetal position so the postural muscles primarily resist motion in that direction.

Tonic muscles on the other hand, are muscles that react to faulty loading by shortening and tightening. They tend to become easily facilitated, meaning they become workaholics very easily and suffer the typical soft tissue stress that goes with doing more than a muscle should. Now, before we go on, let me clarify the term "faulty loading." Faulty loading, as it is used in this article, means any over-use, under-use, abuse (such as trauma) or disuse such as not getting adequate exercise.

Tonic muscles also have a lower threshold of stimulation than other skeletal muscles because their composition is at least 51 percent slow twitch muscle fiber. Slow twitch muscle fibers have a greater capacity for prolonged work, such as aerobic activity or holding you up against gravity.

Vladimir Janda, one the original pioneers who identified some of the tonic and phasic muscles, (see phasic muscles below) also identified that these muscles tended to shorten and tighten in hospital patients exposed to prolonged bed rest, such as those in a coma. These patients needed to be regularly stretched out by physical therapists to avoid problems with joints and connective tissues later on.

Figure 1

Phasic muscles, on the other hand, contain at least 51 percent fast twitch muscle (explosive) and react to faulty loading by lengthening and weakening (relative to their functional antagonists or opposing muscles). This can be quite a problem since the same event that causes a tonic muscle to shorten and tighten can and usually does result in lengthening and relative weakening of any opposing phasic muscle(s). This results in a condition referred to as a muscle imbalance among those in the field of sports conditioning and musculoskeletal rehabilitation (see Figure 1).

Mixed muscles are a third classification, identified by the fact that they don't show any preference to length or strength changes in response to faulty loading not including typical fatigue of course. For example, your deepest abdominal muscle, the transverse abdominis (TVA) and your diaphragm are mixed muscles.

2. The Problem of Muscle Balance

Above, I stated that "tonic muscles" react to faulty loading by shortening and tightening, while "phasic muscles" do just the opposite. This creates quite a problem in the body because, in many instances, tonic and phasic muscles are directly opposed and/or opposed in their postural actions on various joints in the body. This can easily be seen in Figure 1, which shows that as the tonic hip flexor muscles (in red) shorten and tighten, the phasic abdominal and hamstring muscles are strung taunt, becoming longer.

Over time, the tonic muscles actually physically, or structurally shorten, while the stretch stimulus created by a shortened tonic muscle will lead to structural lengthening of a phasic antagonist. This perpetually destabilizes joint structures throughout the entire body, being most problematic locally (the site where the imbalance began) in most cases.

You will see a list of commonly recognized tonic and phasic muscles in the body in Table 1. In short order, you will notice that many of the tonic muscles (such as the pectoralis minor) have phasic antagonists (such as the middle trapezius and rhomboids). With this knowledge, you can now get a real good idea why general stretching rarely helps improve overall musculoskeletal performance, nor does it offer the kind of injury prevention that more skillful application of stretching will.

You must realize that muscles and their connective tissues act like springs, creating tension, and thus force on a joint complex even at rest. If a muscle becomes lengthened or shortened relative to its antagonist, it is much like having some tight strings and some loose strings on your guitar or piano ... it doesn't play good music.

If you show up to a tennis match and just stretch all you muscles, "Will you be balancing the system for improved joint stability, injury prevention and improved performance?"

The answer is no. No more than if you loosen or tighten all the strings of an out-of-tune string instrument.

[To stretch most effectively requires that you test each of the tonic muscles to see which of them are shortened and in need of balancing. This will automatically improve the function and balance of a phasic antagonist. While describing all the tests to be done is too much for this article, those of you interested in accurately assessing your muscle balance can study my book, The Golf Biomechanic's Manual, which shows you the specific muscle tests and corrective stretches.]

For those of you wanting a less technical but effective method for identifying which muscles to stretch so you can balance your body before any work or exercise activity, or just to improve energy flow in your body, I suggest investing in my book "How To Eat, Move and Be Healthy!".

In "How To Eat, Move and Be Healthy!" I show you exactly how to execute the 20 most commonly used stretches as a stretch test. Having completed the 20 stretch tests, you then proceed to only stretch the short-tight muscles, so you can balance your body like you would tune an out-of-balance string instrument.

While I do recommend the books cited for the wealth of practical information in them, you can also balance your body by simply trying any and all the stretches you know and sticking to the following premise:

"If it's not tight -- don't stretch it!"

Failing to follow this simple guideline will only result in one of two responses:

1. If you complete the typical general stretching routine, you will simply be loose and out of balance

2. Not stretching an out of balance body and simply exercising just results in a progressively tighter, potentially brittle out of balance body

Neither is optimal for your health or performance.

Continued on Page 2