Sit on a bench with your back upright. Brace core and raise your arms out in front of you keeping them at shoulder level. Lift one foot a few inches off the floor, extending the leg in front of you.
Raise your body to a standing position by pushing through your heel of your supporting foot and extending the hips and knees. Keep elevated leg locked. Pause, then lower back to starting position. Repeat movement for all reps then switch legs.