Mountain climbers
A fast plank-based drill that drives your knees toward your chest in turn, working your core and shoulders as your heart rate climbs.
IntermediateNo equipmentHigh impactSuggested: 30 sec
How to do it
- Start in a high plank with your hands under your shoulders and your body in a straight line.
- Drive one knee in toward your chest.
- Switch legs in one quick motion, sending that foot back as the other knee drives in.
- Keep alternating at a steady pace while your hands stay planted.
Alternate sides with each rep.
Form tips
- Keep your hips in line with your shoulders and heels instead of piking them up.
- Brace your core so your lower back does not sag.
- Step each foot in slowly for a lower-impact version.
Muscles worked
AbsShouldersHip flexorsQuads