Trainer: Alexia Clark, personal trainer at Alexia Fitness in Scottsdale, Arizona

Benefit: When you have less than 30 minutes to hit up a workout, you need something that is going to give you the biggest bang for your buck. This kettlebell workout is the answer. In just 20 minutes, you'll hammer every muscle from head to toe and seriously rev your metabolism.

(Get dozens of free workouts on your phone with the FREE Men's Health App. Download it here.)

Directions: Perform the exercises below in the order listed.

1. Kettlebell split switch curl to press, 60 seconds.

2. Kettlebell staggered kneeling single-arm clean and press to elbow to floor, 30 seconds per side.

3. Kettlebell split hold single-arm high pull, 30 seconds per side.

4. Kettlebell overhead snatch to overhead squat, 60 seconds.

That's 1 round. Do 3 to 5 rounds.

More Men's Health:
-- Why Do People Love CrossFit So Much?
-- Build A Butt Women Will Want To Grab With This One Simple Exercise
-- The Rock's Secret Weapon For Building Muscle
-- This 5-Minute Core Workout Will Make Your Abs Beg For Mercy

Story continues below