Lower-back extension on ball with ball

Extend the trunk or hips until you return to neutral, not into excessive hyperextension. Lower slowly while keeping the abdominal wall active. Keep the same range from repetition to repetition instead of speeding up as you fatigue. Breathe continuously and end the set before technique starts to break down.

Choose a resistance that lets you preserve technique from start to finish. You should feel most of the work in glutes and hip flexors and lower back; if you feel sharp pain, joint pinching or a clear loss of control, reduce the load or range and stop if symptoms persist.