The Canadian Physical Activity Guidelines recommend that adults accumulate 150 minutes of aerobic activity per week and participate in strength-based activities twice per week. Being active offers a variety of health benefits. But when it comes to cardio versus weights, which is better for weight loss?
If your goal is weight loss, then you need to have a calorie deficit. This means you need to expend more calories then you consume through food and drinks. Calorie per calorie, cardio burns more calories than lifting weights. The average adult will burn 818 calories during 40 minutes of running versus 245 calories during 40 minutes of strength training.
Despite the superior calorie burn during cardio workouts, those promoting weight training for weight loss point to its ability to increase muscle. How this ties in with weight loss is the impact of muscle on metabolism. Muscle burns more calories than fat. 1 lb of muscle burns about 6 calories per day, versus 2 calories per day for fat. While this may seem like a huge difference, it is often blown out of proportion. For instance, if you were to gain 5 pounds of muscle through weight lifting that’s only an extra 30 calories per day. On top of this, building muscle is not easy and not guaranteed with strength training. Building muscle mass will not make body fat disappear nor is fat converted into muscle.
Another common reason people promote strength training is because of its influence on post-exercise oxygen consumption (EPOC). In layman’s terms, this refers to the “after burn”, or the extra calories burned after exercise to help the body recover. The EPOC after strength training is higher than after cardiovascular exercise. However, experts have grown more conservative in the EPOC post strength workouts. It may not be significantly greater than post run. The EPOC for strength training is also dependent on many variables such as strength, reps, time, rest etc.
I’m certainly not discouraging engaging in strength training. In fact, I think strength training is very important. Strength training can help you get stronger so that you can workout harder. It can also help maintain metabolism by helping off set the decrease in muscle that occurs with age. Personally, I engage in strength training session 2-3 times per week. However, I do think we need to be careful that we don’t forget the important benefits of aerobic based activities because of the recent strength training hype.
Finally, exercise, regardless of the type, does not guarantee weight loss. As mentioned, for weight loss to occur, we need to expend more calories then we consume. Evidently, what and how much we eat is hugely important. Many people make the mistake of overestimating the calories they burned during exercise, or have an extra treat because they worked out. This can often sabotage weight loss goals despite grueling gym sessions.