This exercise hits what are likely the most neglected muscles on your body: your glutes and hamstrings. So it's great way to work your backside. While it may look too simple to be effective, you'll no doubt quickly find out why this is a fantastic movement to include in your workout.
Lie on your back on the floor with your knees bent and your feet flat on the floor. (Like you're about to do a sit-up or crunch.) Place your arms on the floor and out to your sides at a 45-degree angle, your palms facing up.
Squeeze your glutes (your butt muscles) and raise your hips so your body forms a straight line from your shoulders to your knees.
Pause for two seconds, then take two seconds to lower your body back to the starting position. That's one repetition. Do 12 to 15 repetitions, rest 60 seconds and repeat one to two times.
If that's too easy, cross your arms in front of your chest, instead of bracing them against the floor.
Still not hard enough? Place a weight plate on your hips (you can secure it with your hands).
To further increase the difficulty, perform the single-leg version of the exercise by pulling one knee to your chest for the entire movement. (Just bend your knee and bring it toward your chest, and hold it there with both hands.) Finish all your repetitions, then switch legs and repeat.
Also, if the back of your leg (your hamstring) starts to cramp — part of the muscle may feel like it has contracted into a tight ball — as soon as you begin the exercise, lift your toes off the floor so that only your heel is in contact with the ground as you perform the movement. This should alleviate the problem.
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