If you've reached day four of the 5-day Total-body Strength-building Challenge from Jen Romanelli, personal trainer and co-owner of Trooper Fitness, you're probably already starting to feel stronger and look more ripped than you did last week.

Today, you'll focus on building dynamic lower-body strength and speed by working your legs with a mix of squats, deadlifts, and hamstring-specific exercises. These moves not only improve your overall lower-body strength and power production, but—bonus—also help increase your testosterone levels.

Directions

Perform the exercise pairs (marked A and B) as supersets. You’ll do a set of A and then a set of B before resting. Repeat for all the prescribed sets. Exercise 1, the box squat, is done with conventional straight sets.

Depending upon your ability, you may increase or decrease the rest periods between sets.

For more dynamic work

Check out our favorite 10 outdoor workouts to burn fat and build muscle, our best dynamic warmup for any workout, and our six full-body UFC workouts for strength, endurance, and fat loss.

For a complete archive of our daily quick-hit routines, go to mensfitness.com/todaysworkout.