Mountain Climbers Reps: Repeat for one minute. Begin with mountain climbers to warm up. Here's how to do it: 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. Swiftly 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. Do this for one minute. Image Source: POPSUGAR Photography