Number 1: Mountain Climbers
- Start in a traditional push-up starting position — shoulders over hands and weight on just your toes.
- Bring your right foot forward, bending the knee and putting weight on the ball of your foot.
- Switch legs, bringing the left knee forward while moving the right leg back. It feels a little like running in place in a plank position.
- For an advanced variation to work your abs more, keep the ball of your foot off the floor as you bring the knee in toward your chest.
- Quickly move through this exercise for as long as possible without taking a break — at least 30 seconds! Take a quick breather if need be, but pick up again until one minute is up.