Life gets busy and chaotic, and taking an hour to train your legs every Tuesday and Thursday isn't always possible. Good news: Daily workouts don't have to take all day! These fast-paced circuits are a great way to maximize your time, burn fat, and get the most from your trip to the gym. Crush your workout and spare your schedule with these athlete-recommended training sessions!

1. HIIT Leg Training

BPI co-founder James Grage carves out killer quads with a leg workout which combines high-intensity interval training (HIIT) and weights. HIIT keeps your heart rate elevated for the entire workout. Not only does it burn fat, it kicks your cardio up a notch by turning standard steady state into explosive movements that help build muscle.

Here's a workout that will help you own leg day. These exercises will target your quads, glutes, hammies, and even calves. The best part? HIIT keeps you burning calories long after your workout ends. This might be a 20-minute workout on the clock, but the real benefits of strength, size, and speed will last much longer.

HIIT Your Legs Workout

In the following workout, you'll perform a strength movement to kick things off, dive into a round of HIIT plyometrics, and continue back and forth between strength exercises and HIIT cardio rounds.

2. HIIT Chest Training

James combines isolation chest exercises with high-intensity cardio to make the most of minimal workout time. Jumping rope between strength-training exercises, like the bench press, elevates your heart rate and burns more calories. You'll leave the gym pumped and conditioned.

HIIT Your Chest

In the following workout, you'll perform a strength movement to kick things off, dive into a round of HIIT plyometrics, and continue back and forth between strength exercises and HIIT cardio rounds.

3. 20-Minute Full Body Tabata Workout

Brendy Scheerer, franchise sales director at BPI Sports, follows a cardio-strength-inspired Tabata routine. Each segment of her workout requires 20 seconds of high-intensity cardio followed by 10 seconds of rest, and then 20 seconds of high-intensity strength moves followed by 10 seconds of rest. This workout burns fat and builds muscle. It will kick your butt in minimal time. But, don't be fooled, you'll certainly be covered in sweat by the end!

4. Deadmill Sprints

What's harder than jumping on the treadmill and booking it at 7 mph? Jumping on treadmill and booking it when the treadmill's off! This zero-powered modification to a traditional run forces you to become your own powerhouse as you push against the machine with maximum force. Turn the power off and revv your metabolism up.

5. Sled Workout

Whitney Reid, BPI east coast sales manager and fitness model, incorporates sleds into his workouts. But, these aren't your standard concrete-slab sled pushes. Whitney uses carpet for a more intense workout.

"Dragging the sled while walking backward is a killer workout for your quads," he says. "The key is to stay low and take longer strides." Whitney also integrates pulling into his routine. By pulling the sled when walking forward, he places focus on the hamstrings and glutes.

6. Bodacious Booty Circuit

IFBB Pro Barbara Bolotte loves training legs but, when she only has a few moments to squeeze in a workout, she targets her glutes. "Glutes are one of the largest muscles in your body, and you can spend plenty of time and lots of reps sculpting and toning them to perfection," she says. Get creative with exercises which allow you to isolate that major muscle.

Bodacious Booty Circuit

40-second recovery in between exercises One minute thirty seconds of recovery between rounds.