Lie on your back, lift one leg (the left one) (hip and knee at approx. 90°), and place the opposite hand (the right one) against the knee (crossed over). Press the hand and knee together without moving (isometric). Optional: Lift your upper body slightly (crunch position) to increase the tension.
Attention:
Do not arch your back (keep your lower back flat on the floor); do not apply too little pressure (lack of tension makes the exercise ineffective); do not strain your neck when lifting (only tilt your head slightly, do not pull); do not tilt or rotate your pelvis (keep it stable); do not hold your breath (continue to breathe calmly).
Lighten:
Keep your head on the floor (no crunches); reduce the pressure between your hand and knee; raise your supporting leg for greater stability; keep the movement shorter (just find the position, don’t push all the way down).
Harden:
Lift your upper body (hold the crunch position); increase the pressure between your hand and knee; keep your free leg straight, just above the floor.
