Exercise Myth #3
Stretch before you workout to prevent injuries... mostly myth
Stretching a cold muscle especially if you're outside in cold weather can often do more harm than good. A better approach is to warm up for a mininum of 5 minutes. A good warmup technique is starting gradually like walking or riding a recumbant bike on light resistance to prepare your body for more vigorous exercise. Many recent studies show that you don't even need to stretch before exercise as long as you're warmed up.
The most neglected and most important time to stretch is at the end of your exercise routine. Your muscles will be nice and warm so you will be able to hold the stretches longer and with less discomfort. You've been spending your workout shortening and contracting the muscle, therefore elongate and stretch the muscle afterward.
Hold each stretch for a minimum of 20 to 30 seconds in order to improve your flexibility. Do not bounce into your stretches. Bouncing or doing balistic stretching can actually rip little muscle fibers and cause damage. You should feel tightness or slight discomfort, but not pain. Once the discomfort has eased up, you can then take the stretch a little deeper and hold for an additional 20 - 30 seconds to get the most out of your stretches.