By David Reavy for Men's Journal
Starting a workout cold increases your risk of injury, and you won't be able to perform your best until your muscles are warm. Fortunately, muscle priming can be boiled down to one essential move: the functional lunge. This dynamic exercise fires everything -– legs, glutes, core, back and shoulders. It's also a great way to open up the hips.
Step 1: Lunge
Begin in a split stance, back knee slightly bent, front leg at a 90-degree angle with your weight in your front heel; bring your arms into a W, squeezing your shoulder blades together and down. Hinge from your hips and reach your arms in front of you, as if you were trying to grab something a few feet out of grasp. Keep your back flat and return to the W position.
Step 2: Lean, Twist
Shift back to an upright torso. With your arms still in a W position, lean deeply to your left, then right. Now twist your torso left to right.
Step 3: Stretch
Finally, bring your back knee close to the floor; you'll feel the stretch throughout your hip flexors. Drive straight up to come out of the lunge, and repeat on the opposite leg for one rep. Do five reps total. Now you're ready to work out.
If you have a few more minutes...
Do any form of cardio that boosts your heart rate for three minutes after you've finished the lunges. If you warm up your cardiovascular system along with your muscles, the rest of your training will feel easier.