Mountain climbers - Plyometric - PHOTO - Women's Health & Fitness

Mountain Climbers

What it hits: Deltoids, biceps, triceps, pecs, obliques, abs, traps, quads, hamstrings, hip adductors and hip abductors

Crash course: A full-body workout that burns more calories in less time by engaging as many muscles as possible.

Make it work: Get into a plank position so your hands are directly under your chest at shoulder-width apart. Arms are straight and body should form a straight line from shoulders to ankles. Lift your left foot off the floor and raise your knee as close to your chest as you can while ensuring that abs stay tight and body stays straight. Return back to your starting position and immediately execute the same motion with other leg. Alternate your legs as quickly as possible while still retaining your form.

The rules: Each leg 1 minute as fast as you can go.