Rep: Complete your target number of reps, then switch to your other side. Complete 20 to 30 reps.
Advanced form: When working the right leg during this exercise, hold your left arm off the ground and extend it in front of you. By removing one of the supports for your body, you introduce instability to the exercise. Switch arms and repeat on the other side.
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Hip Raises
Muscle Targets: Glutes, lower back, abs (transverse)
Equipment: Medicine ball (advanced)
Form
1. Lie face-up on your exercise mat, with your knees bent, your legs together, and your feet flat on the floor.
2. Raise your hips in the air until you have achieved a straight line from your knees to your upper body.
Rep: Lower down to the starting position. This constitutes 1 rep. Complete 20 to 50 reps.
Tip: Be sure to keep the raised leg in the same position throughout; only your hips should be rising up.
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Coach's note: This exercise works the muscles on the back of your body, especially the glutes, while also providing a good stretch for the hip flexor muscles on the front of your body.
Advanced forms: Stretch one leg straight out, and hold it just a couple of inches off the floor. Now push off your other foot and raise your hips up in the air. Perform the target number of reps, then repeat on the other side.
This is similar to the one-legged form above, except you plant one leg on a medicine ball instead of on the floor, which engages the hamstrings of your planted leg as they prevent the ball from rolling away.
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