Taking a few moments to stretch contributes enormously to your fitness routine: it builds flexibility, increases your range of movement, improves posture, helps you relax both mentally and physically, and even reduces your risk of injury.
The Obesity Action Coalition offers a safe, simple approach to effective stretching:
Before stretching, take a few minutes to warm up, as stretching cold muscles may increase your chances for injury. Begin with a simple, low-intensity warm-up such as walking while swinging your arms in a wide circle. Spend at least 5- 10 minutes warming up prior to stretching. The general recommendation for people starting an exercise program is to perform gentle dynamic-type stretches before a workout, and static stretches afterwards.