When Not to Stretch
Earlier this month, I explained why most experts now agree that stretching cold muscles before you start a workout is not beneficial, and can actually injure your muscle(s). Imagine stretching a cold, tight rubber band. It can easily snap, or at minimum, develop some micro-tears. The analogy applies well to cold muscles. That’s why a dynamic warm up involving moving different parts of your body in rhythmic motion, or walking and then marching in place while swinging your arms, even jumping jacks, are all better suited to “warming up muscles” so that they become more pliable, without putting them at risk for injury. You can then proceed from the warm up into your full exercise routine.
Cold stretching before a weight training session might also affect your balance, decreasing it by as much as 23%. The stretching appears to loosen tendons around muscles, and a slack tendon is less supportive and also has more difficulty generating the power needed to perform a weight exercise.