Stretching before may be called the “warm up” and after it may be called the “cool down”, but they do the same thing. They prepare your body for more vigorous movement by warming your muscles and improving your flexibility. At the end of your exercise, stretching helps to cool down those muscles and stretches out those you’ve used and others that protect you as you go through the day.
What happens when you stretch? Muscles allow the body to move by contracting and generating tension. They protect our bones, which protect our essential organs so this is a system that works together. Bones, tendons and ligaments can not make the body move. Muscles are unique in that that’s what they do. We all know what happens to people who suffer from muscular diseases, so it behooves us to protect ours.
Many professionals suggest warming up a bit before you stretch. Some people advise using heat on muscles and others recommend a warm room. Both may increase your static stretches. Still others suggest active warm up. They add a quick activity before stretching. It would appear that this more aerobic activity lowers the rate of injury and many professionals have this as part of exercise classes to protect their pupils.
Many people ask how long to hold a stretch. First let’s look at the term viscoelastic because it describes our muscles. An elastic substance like a rubber band can stretch for a specific force and then return to its original length. The effect is not dependent on time.
On the other hand a viscous substance’s movement relies on time. Think about honey. A viscoelastic substance shows both of these properties. A muscle length increases over time if constant force is applied, or the force decreases over time if the muscle is stretched to a constant length and held. When the force is removed, the substance slowly returns to its original length. People may tell you that stretching affects tendons, but it mostly affects the least stiff section, i.e. the resting muscle, and minimally affects the stiffness of tendons.
The immediate effect and long term effects of stretching have shown to be individualized. For some people 10-second stretches were as beneficial as 20- or 30-second stretches. Experts suggest that people seek professional advice when designing an exercise program because all of us are different. For example, injured tissue or weakened muscles can change viscoelasticity.
Professionals advise to stretch until you feel a certain amount of tension or slight pulling associated with this length, but no pain. As the stretch is held, stress-relaxation occurs, and the force on the muscles decreases. When you feel less tension because of the changes in viscoelasticity and an analgesic effect, you can simply increase the muscle length again until you feel the original tension. This second part of the stretch is held until you feel no further increase.
One 30-second stretch per muscle group appears to be sufficient to increase range of motion in most healthy people; it is more likely that those of us with chronic diseases or weaknesses will most likely need longer stretches and more repetitions.
There are various kinds of stretching so let’s look at those:
Ballistic Stretching: This uses momentum of a moving body or a limb in an attempt to force the body beyond its normal range of motion. This is warming up or stretching by bouncing into or out of a stretched position, using stretched muscles as a spring that pulls you out of a stretched position (think of bouncing down repeatedly to touch your toes). Think about what you just read and you’ll know that this type of stretching is usually not thought to be useful and, in fact it can lead to injury. This type of movement can, in fact, make your muscles tighten rather than lengthen.
Dynamic Stretching: These stretches involve moving parts of your body and gradually increasing reach, speed of movement, or both. It consists of controlled leg and arm swings that take you gently to the limits of your range of movement. An example would be controlled leg swings, arm swings, and torso twists, the backbone of many cool downs and warm ups.
It is suggested that you repeat these 8-12 times, but once again you will know what you need to do. Do not bounce into these movements. Then they would become ballistic movements and you just read about those. Repeat dynamic stretches only as long as you do not decrease your range of movement. If you continue to do these for too long of a time after getting to your maximal range of motion, you then have to overcome these memories of action to make further progress, so get to that good spot and then go on another stretch.
Active Stretching: This may be listed as static/active stretching; but is all the same thing. An active stretch is one where you assume a position and hold it with no assistance other than the strength of your antagonist muscles. One example is that ballet stretch where you lift your leg high and hold it there without anything keeping your leg in that extended position.
The tension of the antagonists in an active stretch helps to relax the muscles being stretched by reciprocal inhibition. If you have taken a yoga class you know what we mean by active stretching. These are usually held for about 10 seconds to 15 seconds. As they get harder I know I tend to start slowly and try to breath through longer stretches. Before I tried yoga, I never thought you could break a sweat in a posture, but believe me, you will.
Passive Stretching: This is also called relaxed stretching. In these movements you assume a position and hold it with some other part of the body. Sometimes you can do these stretches with a partner. Examples include stretching your leg and holding it with your hand or with a towel. A split is also a passive stretch as you are using the floor to maintain that position. These slow relaxed stretches are useful in relieving spasms in muscles that are healing after an injury. They are also good for cooling down after a workout.
Static Stretching: Static and passive stretching are often used interchangeably. Here are the exact definitions just in case you speak to a professional who does not do that. Static stretching involves holding a position to the farthest point. Passive stretching involves an external force, which is created by an outside agent, either manually or mechanically, that helps you stretch.
Isometric Stretching: These stretches involve resistance of muscle groups through isometric contractions of the stretched muscles. It is one of the fastest ways to develop static-passive flexibility and is more effective than either passive or active stretching alone. Most people use their bodies for resistance. You can also use either a partner or apparatus to do these stretches. Foe example, have a friend support your lifted leg and you try to lower it.
PNF Stretching: PNF stands for proprioceptive neuromuscular facilitation. What it does is combine passive stretching and isometric stretching in order to achieve maximum static flexibility. It was developed to rehabilitate stroke patients. Most exercises employ isometric antagonist contraction/relation where the stretched muscles are contracted with a 20-second rest in-between.