Stretching and warming up are essential to preventing injury, increasing and creating balance throughout the body. But there is a difference between the two.
A lot of misinformed fitness professionals and coaches static stretch their clients and athletes before strength training, endurance, sport, ect. They do this in order to “warm up the muscles”.
The problem is that static stretching does not warm-up the muscles and should not be done pre-training. It has been seen to interfere with proper nerve function causing loss of strength and proprioception (sense of self in space), decreasing performance and actually increasing risk of injury.
When Should Stretching Be Done Then?
Static stretching should only be done to muscles that are overly tight and need to be stretched. Being hyperflexible is only slighty less dangerous than being hypoflexible. In other words, do not stretch muscles that do not feel tight or a joint that has full range of motion. Static stretching is best done when the muscles are warmed up (post exercise, body temperature over 109) and/or right before bed, so that when your body repairs at night, it repairs the muscles to their ideal range of motion (ROM).
What is the ideal or average Range of Motion?
|Normal Values for Range of Motion of Joints according to Merck Manual|
|Interphalangeal joints of toes||Flexion||0–50|
|Shoulder||Flexion to 90°||0–90|
|Abduction to 90°||0–90|
|Interphalangeal proximal joints of fingers||Flexion||0–120|
|Interphalangeal distal joints of fingers||Flexion||0–80|
|Metacarpophalangeal joint of thumb||Abduction||0–50|
|Interphalangeal joint of thumb||Flexion||0–90|
*A goniometer would be ideal for measuring joint angles, but visual estimates are just as good to me.
Lastly, it must be understood that static stretching is not the only way to increase joint flexibility. Strength training is also a great way to build flexibility in the joints from neurological demands and actual tissue manipulation.