If you watch “The Biggest Loser,” you may think that the key to weight loss success is how much you can sweat and suffer. While many fitness trainers may want you to believe that exercise is crucial to lose weight, some studies show cutting calories with food is the more effective way to reach your weight loss goals. Here’s why:
To lose about 1-2 pounds a week, you need to achieve an energy deficit (body burns off more than the calories consumed) of 500-1000 calories per day from your current diet and exercise habits. To reach 500 calories via exercise, you’d have to walk, run or cycle about five miles. Most people don’t come anywhere close to burning off 500 calories from exercise alone in their daily lives. However, a 500 calorie deficit with your diet is easily achieved with two or more simple substitutions in your food choices. (i.e., having a salad in place of a sandwich, eating out less frequently, switching to calorie-free beverages, skipping dessert).
In a recent editorial published in the British Journal of Sports Medicine, researchers at the Academy of Medical Royal Colleges wrote that “regular physical activity reduces risk for cardiovascular disease, type 2 diabetes, dementia and some cancers but it does not promote weight loss.” While I have seen some athletes peel off pounds when they get serious about training, most people (weekend warriors) just don’t work out for the required intensity or duration to burn 500 or more calories from exercise.
That’s why I always tell my clients to focus on diet first for weight loss, and exercise second. Ideally, they do both because they really do go hand-in-hand. When I see the many CrossFit women at competitions and they have rock-hard abs and strong butts and thighs, I often see how dialed in they are with their diet. While they certainly lift lots of heavy weights to grow their muscles, the leanness in their bodies comes from sticking to a diet regimen. Studies show that some 98% of the successful dieters who are part of the National Weight Control Registry modified their diet to achieve their weight loss goals and 94% modified their exercise habits.
Bottom line: If you want to lose weight, focus on what you eat first and try to up your exercise as much as you can. And, be sure to recognize that exercise often stimulates your appetite so you will need to really focus on eating foods that help fill you up—not out (like these picks).