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Preteens won't begin to build real muscle mass until they hit puberty, so strength training using weights, with the goal of creating new muscle, shouldn't begin until that point, according to the website KidsHealth.

However, preteens can benefit from exercises that use their own body weight to tone their muscles and prepare those muscles for the growth they'll experience in puberty. Try 15 to 20 minutes of exercises such as pushups, stomach crunches, pullups and leg lunges.

Preteens should perform these on alternate days to make sure their muscles and ligaments have a day to recover from a session. Preteen exercises should be fun - otherwise, they'll feel like a chore, and kids won't want to perform them.

If you're supervising a group of preteens, try making their exercises into games. For example, you can hold jump-rope contests or races for the aerobic part of their exercise routine, or perform lunges and stretches to music. In addition, preteens should make sure to cool down after aerobic activity or strength training 2.

Warm-Up Exercises. Before engaging in vigorous aerobic activities, preteens should warm up with up to eight minutes of fast walking, jumping jacks, stretching or . Sep 09, Torch major calories with this cardio and abs-sculpting workout from Jeanette Jenkins, the Hollywood Trainer. This workout includes moves like . View the latest news and breaking news today for U.S., world, weather, entertainment, politics and health at livoniasend.com

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