We hear it all the time - 20% exercise, 80% diet. Or, wait…is it 30% exercise and 70% diet? Aren’t abs made in the kitchen, but you won’t get definition without some heavy liftin’?
It’s not that these sayings are untrue so much as they’re misleading. No worries, I’m here to clear this up for you.
There is no mathematical way to break down whether exercise or diet is more important for your goals. If you want to run a marathon, changing your diet isn’t going to help you with endurance. Exercise, specifically running, will. This goes the same for any goal - gaining muscle isn’t achieved by just increasing protein consumption, it’s gained by exercise. Sure, the two go hand in hand, but is it really as simple as an 80/20 or 70/30 ratio?
So what are these numbers trying to tell us? If you’re falling short on your goals - fitness or weight loss - you need to look at your diet. If you don’t appropriately fuel your body you’re not going to get anything out of it. Additionally, if you’re trying to lose weight, falling into the “exercise your pizza away” trap will lead to a vicious cycle. Exercise should never be a compensatory tool for any meal you just ate.
The truth of the matter is that diet is very important, and much easier to tailor than exercise for weight loss. If you want to lose weight, you must create a caloric deficit (you can read about this here). Creating a calorific deficit by switching out high calorie foods with low nutrient density for low calorie foods with high nutrient density (see: trading pizza for chicken breast) is much easier and takes all of 1 minute. If you wanted to burn those calories off, you’re committing yourself to miles of running or hours at the gym. It’s easier to rein in your diet and make small changes here and there than to spend surplus time at the gym to “make up” for a bad diet.
Additionally, people tend to underestimate what they eat and overestimate what they burn. The science behind burning calories is not exact. The science behind the caloric content of your food an estimate. Watching your portions is easier, and more effective, then plugging away on the treadmill for 4 hours every morning.
Diet is important because your body requires fuel to function. It also takes less time to swap out high calorie for low calorie than exercising “off” excess calories.
Exercise is important because without challenging your body, you’ll never see results. Lifting weights, running, swimming, etc. is how you increase muscle mass, strength, endurance or cardiovascular healthy. Diet alone cannot do that.
It’s not x% vs. x% - it’s a good balance between fueling your body and making it work hard.