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It’s leg day so you know what that means… sit-ups. Yes, you read correctly. While you may have thought your abs were the only muscle working overtime in this type of move, prepare for those legs to burn.

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In just 15 minutes, you'll power through 4 circuits with a 1-minute max reps circuit to finish strong. Perform each move with a pyramid-style rep-scheme with a static hold between each set. (Not sure what that means? Just following along.) Through squats, extended-leg sit-ups, jump squats, and a lying glute bridge press, you’ll build muscle, strength, and endurance in your lower body. No equipment? No problem. This workout requires nothing but your body weight, so press play and get going.

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