Back in the day when I played team sports in school, we warmed up with stretches, but my how things have changed. Repeated studies have shown that stretching a cold muscle isn't safe — they're more likely to tear — and it's less effective. New research has found that stretching before exercise may actually make muscles contract and become shorter, the exact opposite of what you want before working out.
Skip the static stretching, like bending over to touch your toes for a half minute, before embarking on your fitness routine be it running or strength training. Instead try an active warmup that gets the blood flowing and primes the muscles and joints for movement. Jogging or walking briskly works as well.