Stretching is a powerful part of any exercise program. Most aerobic and strength training programs inherently cause your muscles to contract and 
tighten.
Stretching after you exercise may help improve the range of motion about your joints and boost circulation.
Overall, however, stretching after exercise can help you to optimize your joint range of motion. If you don’t exercise regularly, you may want to stretch a few times a week after a brief warm-up to maintain flexibility.
