Many people turn to the trusty treadmill or elliptical as methods for managing their weight. Most commercial gyms feature rows upon rows of such cardio devices; they’re practically synonymous with exercise. Yet while general cardio exercise is great for health and improving your endurance, relying too heavily on steady-state cardio for weight loss might not be your best bet.
Here, I’ll explain why overdoing cardio can work against your weight-loss journey—and how to adjust your outlook and routine for better results.
How Does Weight Loss Work?
Generally speaking, weight loss is the product of being in a negative energy balance, or a state in which you consume fewer calories than you burn. We also call this an energy deficit. The thing is, this equation only predicts weight loss, which is where a more nuanced understanding is important.
Naturally, most people want to lose fat, not muscle. This distinction is critical because muscle can help maintain your metabolism (i.e. how much energy, or calories, your body burns through), which then helps you shed even more fat. Indeed, research shows that the more muscle you have, the more calories you burn! If you lose muscle during your weight-loss process, it can ultimately work against you by reducing your body’s baseline energy needs.
Cardio and Weight Loss
It’s no secret that you burn calories during steady-state cardio. In fact, you can burn anywhere from 200 to 500 calories (or even more if you’re really going for it) by walking or jogging for about 30 minutes. This helps tip the scale in the direction of an energy deficit, sure, but think about this for a second: The average candy bar contains about 250-300 calories, which means your sweet tooth can cancel out half an hour of cardio in about 30 seconds. So, while steady-state cardio can help burn a handful of calories and can generally help you shed a few pounds when you first get started, I don’t recommend expecting it to work wonders on its own.
Another drawback of traditional lower-intensity cardio is that it’s not super-stressful on your body, especially as you continue with the same steady-state routine over time. Losing fat and building muscle are both adaptations to external stimuli (and you want to do both of these things to sustain weight loss over time). This is a fancy way of saying that you need to stress your body a bit to reach your goals, in part because the process of recovering from such stress burns calories, and in part because it promotes muscle-building, which raises your daily calorie-burn baseline.
Sad but true: Your standard steady-state cardio session doesn’t actually require any sort of recovery process of your body, meaning you don’t burn additional calories after you step off the treadmill (and, of course, don’t build calorie-burning muscle mass).
When Cardio Straight-Up Backfires For Fat Loss
In some cases, a steady-state cardio-only routine actually sabotages your efforts. This happens, most commonly, if you’re eating a low-calorie diet and spinning your wheels for hours on end on cardio equipment. While it’s totally understandable that you might not want to build muscle and get jacked, you don’t want to lose muscle mass—and going hard on cardio, when paired with dieting, is a recipe for muscle loss.
Read More: 8 Possible Reasons Why You’re Losing Muscle
If you’re actively losing muscle, your metabolism is going to dip in response. As a result, you’ll need to consume even fewer calories to maintain an energy deficit, which will then only cause more muscle loss. It’s a vicious cycle.
Another issue with hitting the treadmill hard and long is that doing so could seriously ramp up your hunger—to the point that you might unintentionally eat enough to negate the calories you burned. In fact, research has shown that lots of cardio (particularly in a fasted state, first thing in the morning) can increase hunger significantly. Not necessarily what you want if you’re trying to maintain a caloric deficit.
Best Practices For Incorporating Cardio Into Your Fat-Loss Routine
I’m not saying you have to ditch cardio to lose weight. But taking a “more is more” or a cardio-only approach just won’t work over time.
First of all, if you notice that longer-duration cardio spikes your appetite, you might want to limit sessions to 20 minutes or less. You’ll also want to consume more satiating foods, like vegetables, high-protein eats like meat and protein powder, and anything high in fiber.
Additionally, one of the best things you can do is to add some variation to your exercise routine. Some steady-state cardio is fine, but if you add in some interval training, circuits, and even resistance training, you will see much better results. These other modes of exercise burn more calories in the long run. For instance, both interval training and resistance training induce enough stress within the body that you burn more calories doing them and continue to burn 10 to 15 percent more calories per hour for up to 36 hours afterward. Plus, short bursts of high-intensity cardio can have an appetite-suppressing effect, which may help maintain a caloric deficit. Plus, these other modes also help you maintain (or even gain some) muscle mass. This can help you develop that lean, athletic look.
Perhaps most importantly, though, variety will also keep you engaged in your workout program. If you do something slightly different every time you hit the gym, you’re more likely to enjoy your program and keep coming back. Compliance is the science!
Try This Routine On For Size
Most people trying to lose weight hit the gym about four days per week. Try out this fat loss-friendly sample workout schedule, which offers a solid mix of effective modalities (and, yes, some traditional cardio).
Day 1: 20-mins Steady-State Cardio and Upper-Body Weights
Go ahead and hop on that treadmill, StairMaster, or elliptical and crank away for 20 minutes. Once you’re done, hammer out about three to five pushing and pulling exercises for your upper body (think chest press, rows, pushups, and pullups).
Day 2: Lower-Body Weights
Since your lower body has a ton of muscle, I like to dedicate one day to just them. (Doing cardio on leg days can cause enough fatigue to impact your lifting.) On leg days, I like a variety of squatting, lunging, pressing, and pulling exercises (like deadlifts). It’s going to burn, but who doesn’t want more shapely buns and thighs?
Day 3: Circuit Training + Walk
Usually, I have folks rest a day after leg day—especially when starting out. (Your legs will be so sore that hitting the gym the next day might not be an option. You’ll have a hard enough time getting out of bed!)
Once you’re back in the gym, though, mix it up and do some circuits. These can involve dynamic movements like jumping jacks, burpees, or even plyometrics. They can also involve strength training exercises, core movements, and short bursts of cardio. I like to mix my circuits up and try a new challenge each week.
Aim for 20 to 30 minutes of circuits, then walk on the treadmill at an incline for 10 to 20 minutes.
Day 4: Interval Training
Finally, I love to finish the week with interval training. Think of intervals as a burst of effort followed by not quite enough rest. I personally enjoy 20-second bike sprints with 40 seconds of easy spinning between them; just 10 minutes of that and your legs will be cooked.
The best part about interval training is that your workouts will only be about 15 minutes long when you factor in warming up and cooling down. Those 15 minutes will be absolute hell, but then you can enjoy your weekend!
The Bottom Line
On paper, weight loss is a simple process—and cardio has long been hailed as a key component of that process. However, our bodies are complex and how you incorporate cardio into your journey can make a significant difference in the results you see.
While your fat-loss workout plan can definitely include cardio (even steady-state cardio), you’ll still need to keep tabs on your nutrition and incorporate other modes of exercise (including resistance training) to lose fat over time.
Known as ‘The Muscle Ph.D.,’ Dr. Jacob Wilson has a knack for transforming challenging, complex concepts into understandable lessons that can support your body composition and health goals. A skeletal muscle physiologist and sports nutrition expert, Wilson is a leader in muscle sports nutrition. As the CEO of The Applied Science & Performance Institute, he researches supplementation, nutrition, and their impact on muscle size, strength, and power.