sit-up(redirected from Sit ups)
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A physical exercise in which one uses the abdominal muscles to raise the torso from a supine to a sitting position and then lies back down again without moving the legs.
an exercise in which a person lies flat on the back, lifts the torso to a sitting position, and then lies flat again without changing the position of the legs: formerly done with the legs straight but now usu. done with the knees bent.