Stretching

When should you stretch, for how long and what kind of stretching should you do?

Stretch when your muscles are warm, so that you don’t strain your muscles. Don’t stretch prior to starting your activity unless your body is warm and your sport requires a certain degree of flexibility. Stretching prior to exercise has been shown to decrease force and power. The general recommendation for stretching duration is 20-30 seconds.

A short bout of stretching will: decrease the amount of strength available to the muscle, cause no change in muscle length and decrease discomfort in the muscle.

Regular stretching has been shown to improve the power and speed of muscle contraction. Regular stretching will cause stretch hypertrophy, which means your muscle tissue increases in length, and increases joint flexibility. With irregular stretching, the muscle goes back to its previous length.

Two types of common stretching techniques are static, where you hold the stretch, and ballistic, where you bounce while you stretch.

Ballistic stretching causes the muscle being stretched to be in a state of contraction during the stretch. This means the muscle being stretched is stiffer, and this will have more effect on the tendon, which is what attaches the muscle to bone. Ballistic stretching increases tendon elasticity. A contracted muscle cannot relax and this style of stretching will cause injury if you’re not warmed up.

Static stretching is slow and controlled. It may allow your muscles to relax during the stretch.

The question you need to ask yourself while you are stretching is what part of the body you trying to stretch? How many joints does the muscle cross? What sport are you doing? Do you need that muscle to be long or short? Target a small area and protect the areas around it that may not need to be stretched. There is no blanket prescription for stretching. It varies between sport, person, joints, etc.
There has not been a lot of research on stretching. From athletes involved in sports that need lots of flexibility like gymnastics, it has been found that regular, long-term stretches, held for long periods of time and repetition of these stretches has increased flexibility.
For adults to see a difference in flexibility, it will take up to three months of regular stretching. Children gain flexibility easily.
Stretching the wrong way can lead to injury or overstretching of areas that should be protected.