Mountain Climber

Starting position

• Push-up position, hands under the shoulders.
• Body in a line, core braced.

Execution

• Pull one knee to the chest and put it back.
• Switch to the other leg, alternating briskly.
• The hips stay low.

Common mistakes

• Pushing the hips up.
• Shoulders far behind the hands.
• Just tapping the feet instead of pulling the knees in.