How Many More Calories Does A Fit Person Burn Daily

There are a ton of super generic calculations that attempt to quantify how many calories a person burns daily. But they are all extremely over-simplified and as a result make it impossible to determine what would happen if you changed your body composition. So I wanted to address this issue because in my lifetime I’ve changed my body composition dramatically multiple times and there are pretty big differences in the way it feels, the energy consumed, and how you cope with it.

Caloric Burn By Body Component

Your Basal Metabolic Rate (BMR) is the number of calories you burn as your body performs basic (basal) life-sustaining function. Commonly also termed as Resting Metabolic Rate (RMR), which is the calories burned if you stayed in bed all day.

In order to determine what would happen if a person lost body fat and gained muscle mass we first need to exclude all of the other components in our composition that will not change as a result of improving fitness. Without boring you with a ton of research, here are estimates of what major systems in the body consume in terms of daily calories for a specific example.

200 Pound, 30 Year Old Male, 30% Body Fat

We will assume there is a person who weighs around 200 pounds, who is not very active and has about 30% body fat. The first thing to notice is that the fat and muscles combined consume only about 20% of the person’s daily energy budget. This could vary by a few percentage points based on how we want to calculate it, but don’t get caught up on that, because we’re going to use the same calculation on the next example, so the math will always work out relatively the same.

180 Pound, 30 Year Old Male, 10% Body Fat

Now we’re going to assume that person starts working out and drops 40 pounds of body fat, while adding 20 pounds of pure muscle. This would be a very dramatic body composition change and would require a LOT of work.

What might be surprising is that when we compare the two, the total calories burned per day isn’t that different! This is despite the fact that 20 extra pounds of muscle will burn more calories! But remember, we exchanged 40 pounds of fat for those 20 pounds of muscle.

What Does This Tell Us?

Essentially, unless you intend to put on 100 pounds of muscle, and drop below 10% body fat, the ONLY way to maintain a healthy body composition and be fit and energetic is to control your caloric intake.

There is NO WAY to spend enough time in the gym to make up for a terrible diet.

By the way, that image associated with this post is of Rachit Dua. He transformed from 30% body fat, to being a fitness trainer! Nice!!!

And one of the things he used for guidance was Arnold Schwarzenegger’s blueprint to cut. Here it is: