It may surprise you to know that when lots of people stretch, their stretching is ineffective. Often this is because the muscle they are trying to stretch is in a shortened position. It may feel stiff, sore, tight and tense but will get more so as the stretch reflex switches on – this happens particularly if the stretching is aggressive. It then becomes very difficult to lengthen the muscle because tension limits blood flow. If the whole body is constantly tense, we can see how this might restrict our range of movement.