Fitness guru Brett Hoebel (a.k.a. "El Capitan") has worked as a trainer on NBC's Biggest Loser, as a health expert for the Food Network and now has a series of comprehensive workouts called the 20 Minute Body. The workouts look a lot like weight-free interval training to us – which is a good thing. Here, Brett recommends doing four sets of five moves, with 30 seconds of activity followed by 30 seconds of rest for each move. Shoot for 10 to 12 reps with each set, and feel the burn.
From a sit-up position with your legs slightly bent, pull one knee to your chest and grab it with both hands. Flex your toes, keeping the sole of your foot pointed forward. Release your knee and bring your foot all the way down, planting it as you lean back.
Advanced version: After you pull your knee to your chest, push it into a kick, leading with your heel before you plant your foot and switch legs.
Brett's Tip: Keep your chin tucked with your eyes forward. That keeps your shoulder blades off of the ground and your abs engaged.
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