NPC bikini pro Lindsey Hughes has cultivated an arsenal of ask-kicking skills during her time at Knockout Zone, a martial arts gym in Miami, Florida. Hughes' workout of choice is an intense flurry of boxing, tire flipping, heavy weights, and general badassery. Only sign up if you have a good sweat towel and an iron will.

Hughes loves the physicality of boxing, as well as the burn.

"Obviously, you're burning double the calories in less time," says Hughes. "Like 700, 800 per session. You're also shaping your body, especially the abs, because there is a lot of rotational movement."

In an all-out gauntlet combining timed intervals of battle ropes, box jumps, and sled pushes with intense sets of heavy deadlifts and boxing, Hughes proves that to earn elite strength and stamina, you have to give it your all.

"You're gassed for sure," she explains. "You're dying during the workout, but afterward, once you realize you survived, it's actually a refreshing feeling."

Earn that feeling if you dare!

Why Train Fighter-Style HIIT?

This workout is a fat-burning powerhouse. Several moves are programmed as high-intensity interval training (HIIT), which are short, intense bursts of work with very little rest in between. Add in traditional boxing staples like jumping rope and quick punching combos, and you're working multiple muscle groups while maintaining an elevated heart rate. All of this translates to burning more calories and increasing core strength and agility.

Hughes also points out boxing is a major stress release—you can literally punch your way out of a bad day!

Of course, boxing is only one part of what's going on here. The workout consists of three phases:

• Phase 1: Jump rope and bodyweight
• Phase 2: Boxing intervals
• Phase 3: HIIT Full-Body Battle

Training at home? Do Phases 1 and 2—and do them hard—and you'll get a great workout. Training in a facility where equipment availability isn't a hurdle? Then test yourself—or even better, a group of fearless lifters—against Phase 3.

Each phase is intense is in its own way, but each also feeds into the next. Jumping rope and boxing thoroughly warm up the major muscles of the upper and lower body, which then get worked hard through four intense rounds of full-body exercises like deadlifts, box jumps, battle ropes, and hammer swings. Between Phases 2 and 3, Hughes likes to add a little extra glute activation in the form of 15 steps of lateral band walks in either direction.

If you don't have a tire or sledgehammer, Hughes suggests using a dumbbell to sub for both exercises. Hold weight centered between your knees in a wide squat and jump forward for 10 long jumps. Then immediately use the same dumbbell for single-arm bent-over rows, 10-15 reps on each side.

Lindsey Hughes Fighter-Style Workout

Note: Perform on a bag. If you do not have access to a boxing bag, you can do shadow boxing using very light dumbbells. Remember to stay on your toes and rotate your hips!

Examples of freestyle combos:

• Jab/cross/jab/cross
• Jab/jab/cross
• Alternating body shot
• Alternating hook
• Jab/cross/hook

For more fat-burning tips, follow Lindsey Hughes ( @lindseyreneefit) and Nelson Cardenas (@perseusfit, also appearing in the video) on Instagram.