S1: Front plank on knees or with one leg extended
Key instructions
Facing the floor/mat:
Hold the 'plank' position on your forearms and knees, keeping your back straight. Tighten your core and tuck your buttocks in.
If the exercise is 'easy', extend one of your legs as shown in the video. Alternate between extending your left and right legs to spread the effort evenly
Sets x reps
2x30 sec
Rest between sets: 30 sec to 1 min 30
