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When it comes to gaining flexibility, it is imperative that you warm up the muscles first. Static stretches before a workout do not do much for flexibility let alone prevent injury. Dynamic or range of motion stretches do a lot to open up the muscles prior to workout or even stretching routine. However, flexibility IS gained when stretching during cool down after a workout. So always plan to stick around after class and stretch out because that's when the progress is made.
If you do not have a workout before you stretch, do some jumping jacks or run in place to warm up the muscles and loosen them out prior.
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