Skip to content

Want a Lean Body? Do This One Exercise Over All Others, Say Experts

Trainers agree: If enhanced fat burn and a lean body is your goal, do this every single day.
FACT CHECKED BY Alex Daniel

As our resident trainer always likes to tell us, if you want "lean up" and slim down, you need to start by eating the right foods every day—and preferably at a calorie deficit. Now, with that out of the way, the logical next question is: What's the single best form of exercise you should be doing to help you get that lean body? We asked scores of exercise experts, trainers, and doctors for their answers, and we confess that we're not totally surprised by their answers.

But before we get into it, it's important to remember one of the most important directives of exercise: You need to do what you love doing at the gym or elsewhere, otherwise you won't do it. If you love walking, you can get a lean body walking. If you love running, that's cool, too. Is weightlifting only good for building big muscles? Of course not. You can get lean doing a strength-training regimen. You can even get fit and lean if you love obscure sports and you play them enough and at a relatively high intensity.

"I love pickleball," Dan Buettner, a National Geographic Fellow, longevity researcher, and author of The Blue Zones: Lessons for Living Longer from the People Who've Lived the Longest, once explained. "I can pickleball for two hours, and I won't even know that time went by. And I've elevated my heart rate, I'm using range of motion, [and] I'm developing lower-body strength."

That being said, if you're dead set on burning as much fat as possible and getting lean as quickly as possible in the single most efficient way as possible, there's one workout that stands out—and it's not pickleball. Read on for what it is, and for one amazing example workout that a top trainer provided to us. And for some little tips and tricks to help you along the way, don't miss the Secret Little Exercise Tricks for Getting a Lean Body Fast, Say Experts.

Embrace the Intensity

woman doing a burpee

Of all the trainers we polled about getting lean in the shortest and most efficient manner as possible, the chorus was clear: It's high-intensity interval training (HIIT), or doing short bursts of rapid-fire exercises.

"High Intensity Interval Training combining cardio, strength and power exercises is the most efficient and effective way to train your body," Alissa Tucker, a NASM Certified Personal Trainer, Corrective Exercise Specialist, Certified Yoga Instructor, professional dancer, and AKT Master Trainer, told us. "It's because of the Excess Post Exercise Oxygen Consumption (EPOC), commonly referred to as the 'after burn' effect. The higher intensity the workout, the greater the after-burn effect. This is why HIIT training is so effective."

She explains that when you perform a HIIT workout, it's all about the recovery. "By pushing ourselves to 90-100% of our max heart rate in the high intensity intervals, we are working anaerobically, which means our body is producing energy without oxygen and will create a greater oxygen deficit and require our bodies to work harder and continue to burn more calories post workout in order to recover."

Countless trainers explain that HIIT appears to combine the best of all exercises: You get the benefits of cardio by getting your heart rate up—"it improves oxygen flow in your bloodstream and is great for your heart," says Jeff Parke, of Top Fitness Magazine—and by performing strength-training moves you're promoting muscle growth, which will lead to more calorie-burn as you make gains.

"HIIT is an extremely effective and efficient form of exercise, elevating your heart rate quickly and burning a significant amount of calories in a short amount of time," Tom Holland, MS, CSCS, CISSN, an exercise physiologist and author of The Micro-Workout Plan: Get the Body You Want without the Gym in 15 Minutes or Less a Day, told us. "In addition to torching major calories in a short time frame, there is an additional 'afterburn effect,' where your body continues to burn calories after your workout as it attempts to return to homeostasis." And for more life-changing exercise advice, see here for the Secret Exercise Tricks for Keeping Your Weight Down for Good.

Science Backs Them Up

man pushups

Several studies tout the fat-melting benefits of HIIT. According to one meta-analysis of more than 786 studies on the subject published in The British Journal of Sports Medicine, "Interval training and [moderate-intensity continuous training (MOD)] both reduce body fat percentage," conclude the researchers. "Interval training provided 28.5% greater reductions in total absolute fat mass than MOD." In other words, HIIT burns roughly 29% more body fat that moderate-intensity exercise, which includes brisk walking and jogging.

Another meta-analysis published in the journal Sports Medicine found that high-intensity interval training (HIIT) "significantly reduced total, abdominal, and visceral fat mass, with no differences between the sexes," while also noting that exercise that forced people to exceed "90% peak heart rate" (in other words: it's really intense exercise) was the most effective in losing weight. "HIIT is a time-efficient strategy to decrease fat-mass deposits, including those of abdominal and visceral fat mass," the researchers conclude. And for more clever ways to work your muscles more every day, don't miss The Secret Trick for Getting Fit Using Your Toothbrush.

The Key Is Consistency—And Total-Body Fitness

Side view of a muscular couple doing planking exercises

If your goal is burning fat and getting lean, the important thing, says Holland, is that you stick to a consistent schedule. "In the end, weight loss in general and belly fat specifically both come down to frequency and consistency of cardiovascular exercise," says Holland. "Since lack of time is one of the major reasons people give for failure to adhere to an exercise program, the short duration HIIT workouts with the high caloric expenditure is an extremely effective solution. You can essentially get the same results in half the time with HIIT workouts."

Here's an Amazing Workout to Try

Turned half side full length size photo portrait of beautiful attractive charming confident girl doing squats in spacious large big light modern domestic gym

Here's one sample HIIT routine that's great for even beginners that you can try now, courtesy of Dani Singer, CPT, FNS, CES, of Baltimore's Fit2Go. It's called the "P.A.U.L." method. "The beauty of this workout is that it's only 10 minutes," says Singer. "You can do it at home with nothing but your own bodyweight. So, most importantly—it gets done every day."

She also notes that since you're performing the exercises back-to-back with no rest, "you're strengthening your muscles while also burning fat—you're killing two birds with one stone." And if you perform it at the beginning of your day, you'll reap even more benefits.

"Psychologically, you're starting each day with a win," she says. "Physiologically, you're flooding your bloodstream with endorphins to maximize your mood and energy for the day. When you feel better, you make healthier choices—like what to eat for lunch."

Here's how to do it:

Step One: "Choose one exercise for each of the following 4 categories:

P- Plyometric cardio (e.g. Jumping Jacks)
A- Abs (e.g. Plank)
U- Upper Body (e.g. Push Ups)
L- Lower Body (e.g. Squats)"

Step Two: "Set a timer to beep every 30 seconds, or use an online interval timer."

Step Three: "Perform each exercise for 30 seconds, switching every time you hear the timer beep."

Step Four: "After performing all four exercises, rest 30 seconds and start again. Continue with this circuit until you've reached 10 minutes."

Step Five: "Shower, give yourself a pat on the back, and go crush your day." And for more ways to get fit and lean, check out The 15-Second Exercise Trick That Can Change Your Life.

William Mayle
William Mayle is a UK-based writer who specializes in science, health, fitness, and other lifestyle topics. Read more about William