Often when people stretch, they do it at the beginning of a training session. It's just very common to do it this way, but unfortunately it's incorrect. Static stretching is done to relax muscles and essentially put them to sleep. Therefore it should be done at the end of a training session, not at the beginning. To start a workout, it's best to use dynamic movement such as running in place, jumping jacks, perhaps some gentle rotational exercises, etc. The idea is to get the body moving and raise your core temperature. If you're doing sport specific training, then you may want to incorporate warmup exercises related to that. Then you'll go through your actual workout and finally finish with static stretching. Watch the video to learn more. Although there are many excellent books on the topic of stretching, I have found a trick that allows you to know what stretch to do for every muscle without having to rely on books or websites. Watch the video to learn more.
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