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One workout myth that many people continue to perpetuate is that cardio is the best, or fastest, way to achieve weight loss. While it is true that acting in a caloric deficit will result in weight loss, and that cardio burns more calories in one session than weight training, it may not be the best way to spend your time in the gym.

Cardio doesn’t “burn fat” 

Cardiovascular exercise is catabolic, meaning it breaks muscle tissue down for fuel. Whenever you first begin any kind of cardiovascular exercise - running, swimming, biking - the body will build a small amount of muscle that is needed to perform that exercise. However, your body also adapts very quickly to this kind of exercise. That means, that the more that you do steady-state cardio, aka slogging through the treadmill miles or the elliptical, the more efficient your body becomes. You burn less calories per mile, or fewer calories during your cardio session. Now, becoming more efficient and burning less fuel might be great for marathon running, but for someone looking to shed a few pounds, this is a worrisome spot to be in! So, you have two options.

Option A

Eat less. Ah yes, the classic pitfall. However, let’s talk about why eating less probably won’t happen. Cardiovascular activity starts first by eating up the glycogen stores in your body. Then, it moves on to any sugar that may be in your blood stream. When you blood sugar starts to dip, your body calls upon the hunger hormone - ghrelin - to signal to your body that you’re hungry. This hormone not only stimulates appetite, but promotes fat storage. And guess what? All those cardio sweat sessions that you’ve been putting in have made you more efficient, meaning you burnt less calories. Tell that to your rumbling belly. In addition, evidence has shown that long term, very low calorie diets can have lasting consequences on sustained weight loss.

Option B

Exercise more. This, of course, doesn’t come without its fair share of consequences. In fact, too much cardio puts you at risk of injury and then you’re completely down for the count.

An average person has 30 billion fat cells. Let me write that out for you : 30,000,000,000 fat cells. If you had access to water, but no food, you could survive off of your fat cells for 2-8 weeks. Your body has enough stored muscle and liver glycogen, blood glucose, and free fatty acids circulating in your bloodstream to fuel most daily activities. This includes your cardio sessions.

There is also no “fat-burning” zone. Yes, you might be working at a lower intensity, and working more efficiently, but you are ultimately not burning as many calories during the same amount of time, either.

So what is the best exercise?

There isn’t one “best” form of exercise for everyone, but an exercise regimen that you enjoy is going to be key in sticking with it! Focus on bursts of high-intensity cardio between sets of weight training for the most effective use of your gym time. This provides the higher caloric burn of cardiovascular exercise with the benefits of strength training, without placing undue strain on your body.