Extension and flexion of the legs in supine position ► crunch kick / knee crunch

Individual work

Back position, upper body flat on the floor, arms stretched out to the sides on the floor (or place hands under the buttocks / or clasp hands behind the head), bend legs (knees at buttock height) and stretch back to the starting position in front (bend and stretch legs).

Attention:
Do not put your legs down completely, keep your (lower) back in constant contact with the floor (consciously tense your abdomen).

Lighten:
Just hold the position with slightly bent legs (without stretching your legs), stretch your legs less.

Harden:
Additional weight on, between or on top of your legs.

2 weight cuffs/1 weight disc/(medicine) ball/sandbag ► Make the exercise more difficult (additional weight)