The dynamic warm-up helps young athletes excel and stay healthy

Warming up properly not only helps young athletes prevent injuries, it helps them improve their performance. But don't confuse warming up with stretching, they do two different things.

Warming up is meant to increase the body's core temperature, increasing blood flow to muscles, tendons and ligaments. Muscles only achieve maximum performance when all their blood vessels are dilated. At rest muscles only manage 15 to 20 percent of optimal blood flow, compared to 70 percent or more after only 10 minutes of activity.

An active warm-up also includes specific sport movement patterns to help prepare the athlete's neuromuscular system to meet the vigorous demands of their chosen sport.

The traditional warm-up, running in a straight line for 3 to 4 minutes and then doing a series of static stretches for each muscle group, is less than ideal.

While research shows static stretching increases flexibility, it doesn't prepare a muscle for the active contractions and quick reflexive reactions needed for sport. The same research shows static stretching actually relaxes the muscle, decreasing its power output.

So, should athletes stretch? Absolutely. It's only the timing of stretching that needs to be changed.

Stretch after playing a sport or working out, when muscles have been well heated and are fatigued. That's when muscles need the relaxation of a good stretch.

There is an important difference between warming up and stretching, even though some athletes stretch and call it a warm-up. The active warm-up, performed before doing a sport, specifically targets muscle groups and joints involved in the movements needed for that sport. These are movements requiring short-duration high-intensity work bursts like sprinting or jumping.

A good warm-up can also help reduce the severity of post-exercise muscle soreness. The warm-up's ability to increase blood flow helps deliver more oxygen to the muscles and prevents build-up of unwanted waste products, which can lead to muscle soreness.

During the after-activity cool-down, flexibility-enhancing static stretching can increase joint and muscle range of motion. It can help muscles relax and will also enhance the circulatory system's ability to remove waste products like lactic acid. This will speed the athlete's recovery rate.

Stretch to discomfort, but not to pain. Hold each stretch for two repetitions of 20 seconds each and relax the muscle.

The cool-down period should last 10 minutes.

Remember, the key to a dynamic warm-up is making sure it is progressive, taking each limb through at least the range of motion required by the sport.

To learn more, call the Sports Medicine Center for Young Athletes at Children's Hospital & Research Center Oakland, at (510) 428-4120.