Hollow-body holds are an amazing ab exercise. Never heard of them? Gymnasts perform them regularly in their training regimens as they mimic the lumbopelvic position they regularly use in some of their events. What's great about this exercise is that it builds abdominal posterior pelvic tilting strength and endurance.

Hollow-Rock-Hold

Here's how you do it:

  1. Lie supine with the arms and legs in the air and the knees bent. Flatten out the lumbar spine so there's no gap between the floor and the low back. The upper torso will crunch upward slightly, but you're not actively trying to do this – it's a result of the flattening of the lumbar spine.
  2. Gradually lower the arms and feet toward the floor while maintaining the lumbopelvic position.
  3. Hold this position for time and continue to push the low back into the floor throughout the duration of the set.

Perform 2 sets of 20 seconds at least once a week.

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