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Here’s Why Metabolic Conditioning Is an Efficient Way to Get Fit

Metabolic conditioning optimizes how your body uses energy to burn calories and builds muscle more efficiently.

Tonal Coach Kendall Wood after metabolic conditioning training.
Tonal coach Kendall “Woody” Wood after a tough metabolic conditioning workout.

There are two basic points to exercise, besides the fact that it makes you feel good: to make your muscles stronger, and to help your cardiovascular system work more efficiently. Who wouldn’t want a workout that does both, giving you more bang for your buck every time you break a sweat? Enter: metabolic conditioning.

Over the past decade, this style of exercise has become increasingly popular among people looking for more efficient ways to get fit, but metabolic conditioning workouts aren’t some buzzy trend. 

“Any type of exercise that combines cardio and strength exercises to improve how your heart works and how your muscles respond is metabolic conditioning,” says Tonal Coach Ash Wilking. Steady-state running? High-intensity interval training? Circuit training? Those are all different types of metabolic conditioning.

What Is Metabolic Conditioning? 

In exercise physiology, metabolic conditioning refers to exercise that taps into the body’s immediate and intermediate energy pathways to provide your cells with adenosine triphosphate (ATP). ATP is the energy currency of your cells. During a workout, it helps your muscles contract—and the more ATP that is supplied to working muscles, the longer those muscles can work. 

“The beauty of metabolic conditioning is you can orient it so you can optimize for a variety of outcomes,” explains Jacob Rauch, CSCS, PhD candidate, and Performance Manager of Applied Training Science at Tonal. 

You do that by changing up which of the three energy systems your body prioritizes during a workout: “The phosphagen system is your fastest, most powerful system,” says Rauch. “It’s the first couple seconds of sprinting or Olympic lifting, and it gets depleted very quickly—within 10 seconds, or about three reps. The glycolytic system is a sort of intermediary one, where you can do one to four minutes of higher intensity work. And the oxidative system is for long-duration, lower-intensity efforts.” 

What system you’re using really comes down to the intensity and duration of the exercises you’re performing, not the specific moves. Your phosphagen system will take over when you’re doing short bursts of high-intensity exercise and spending more time resting, while doing slightly less intense exercise, followed by more rest, will fire up the glycolytic system.

If that all sounds confusing, think about heart rate zones instead, says Wilking: Zone one is active recovery and warming up or cooling down; zone two is aerobic, where you’re building cardiovascular endurance, zone four is maximizing things like calorie burn and the cardiovascular improvement, and zone five is power and speed development. Zone three, then, “is the meat and potatoes of strength and conditioning,” she says. “That’s really where we want to focus on circuit training as it relates to metabolic conditioning,” says Wilking.

What Is the Difference between HIIT and Metabolic Conditioning?

If all of this sounds similar to high-intensity interval training, you’re not totally wrong. In HIIT, you alternate between short bursts of intense work followed by less intense or rest periods to significantly increase the heart rate to at least 80 percent of your maximum heart rate.

HIIT is a type of metabolic conditioning, but not all metabolic conditioning is HIIT. Metabolic conditioning is a little more varied and flexible when it comes to work-to-rest ratios, and can include lower-intensity work. But, boiled down to the basics, “metabolic conditioning is a fun, easy way to do a lot of work in a short period of time,” says Rauch.

What does that look like in a session? On Tonal, “our focus with metabolic conditioning is a higher volume of work and lower resistance,” says Wilking. Instead of doing ratios of your one-rep max, like you would in a power workout, or jump squats for 20 seconds, like you would in a HIIT class, you’re going to do reverse lunges for 60 seconds under a moderate load with a shorter rest period. The result: “It feels like resistance training, but at the end of the workout, you’re going to be sweating and really be able to feel that your heart rate came up,” says Wilking.

Is Metabolic Conditioning Good for Fat Loss?

Most familiar forms of cardio (running, biking, the elliptical) fall under the low-intensity, long-duration umbrella, meaning they mainly use the oxidative system to burn fat for fuel. But increasing the intensity of a workout doesn’t mean you can’t tap into that system alongside the phosphagen and glycolytic systems. 

In metabolic conditioning, you’re mostly shifting between moderate- and high-intensity efforts. And working out at both of those intensities can reduce body fat percentage, according to 2017 research in Obesity Reviews. Plus, by combining cardio or strength training into one workout, you can lose fat and gain muscle more quickly and more efficiently than if you were to do each style of exercise solo, a 2018 study published in PLOS One found. 

Tonal Coach Ash Wilking
Tonal coach Ash Wilking

Fat loss is due, in part, to burning more energy than you consume. “The higher the heart rate, the more energy your body is consuming,” says Wilking. And since metabolic conditioning spikes your heart rate more than a traditional resistance training session, that stimulus can potentially decrease fat, she explains.

Can You Maintain Muscle with Metabolic Conditioning?

On Tonal, cardio is an integral part of Get Lean programs. But cardio and strength training are inherent to metabolic conditioning, which means you’re certainly not going to lose muscle while doing metabolic conditioning workouts. 

“Technically, we’re building muscle because we’re working in that eight-plus rep range,” says Wilking. “But we’re also focusing on workload capacity because we’re performing these exercises for extended periods of time, which builds muscle stamina.”

The goal of metabolic conditioning is not to make huge muscle gains; instead you’ll torch calories and continue building lean muscle. “If our focus is to actually build muscle mass or to maintain muscle mass, we’re not going to lose that in creating a metabolic response,” says Wilking. “Your one-rep-max is not necessarily going to increase, but you’re not going to lose anything.”

Metabolic Conditioning Programs and Workouts on Tonal

20-in-20: Metabolic Burn – Coach Ash Wilking 

20-in-20: Metabolic Burn - Coach Ash Wilking 

Transform your body into a fat-burning machine with this all-barbell program that uses high-volume sets—and not much rest—to torch calories. 

20-in-20: Fire Circuits – Ash Wilking

20-in-20: Fire Circuits - Ash Wilking


Join this lean muscle-building, calorie-torching adventure that’ll take your fitness to the next level. Full-body circuits leave you breathless as you drive hypertrophy gains, while a wildcard core workout each week helps develop a strong and stable midsection.

Compound Conditioning – Multi-Coach

Compound Conditioning - Multi-Coach

Focus on mechanics, but keep your output and your heart rate jacked in this fun, but challenging two-week program that efficiently burns fat and builds muscle with multi-joint movements that recruit upper- and lower-body muscles at the same time. 

Metabolic Burnout Circuit and Metabolic Burnout Circuit 2 – Coach Ash Wilking

Push past your limits in these lung-burning workouts that use extended sets to spark hypertrophy and burn fat.