Eating Exercise Calories?

Stewie316

TrainingwithTony, where did you get 80% from? I like your equation a lot better than the eat your exercise calories rule (because unless you're an athlete or in training, exercise calories is no different than calories from normal activity). But 80% seems kind of high.

TrainingWithTonya

TrainingwithTony, where did you get 80% from? I like your equation a lot better than the eat your exercise calories rule (because unless you're an athlete or in training, exercise calories is no different than calories from normal activity). But 80% seems kind of high.

Okay, the formula I use is from my classes at university (nutrition for my minor and my exercise physiology major). Exercise calories and normal activity calories are different. Basically, the basal metabolic rate is estimated based on if you don't get out of bed. Then you add in an activity factor for activity like work, housecleaning, taking care of kids, yard work, whatever makes you move during the day. If you don't do any planned exercise, you can then eat 80% of those total calories to lose weight based on what your body is burning just to maintain its current muscle mass. If you do planned exercise, that counts separately because it isn't done as consistently as the normal routine of walking at work or chasing kids around the house. Plus those exercise calories will vary day to day based on the variety of your workouts. And ideally, you should have variety in your workouts.

The general formula that we use for people who don't get hooked up to our metabolic cart to determine BMR is 1 calorie per hour per kilogram of lean body weight. So, 1 calorie x 24 hours x kg lean body weight. Or if you use pounds of lean body mass, divide the final product by 2.2. This requires doing a body fat analysis and subtracting out fat from total body weight to get the lean body mass. A lot of places just use this formula using total body weight which is a little less accurate because fat doesn't burn the same amount of calories as muscle.

Once you have the BMR, then you multiply by the activity factor for Sedentary (only activity is walking to and from your desk or car) of up to 1.3, Lightly Active (total activities of daily living more then just walking to desk or car, but less then 30 minutes of walking a day) of 1.3 to 1.4, Moderately Active (total activities of daily living more then 30 minutes but less then 45 minutes of walking and may include some high intensity activities like jogging after kids) of 1.5 to 1.6, Highly Active (total activities of daily living more then 45 minutes but less then 60 minutes of walking and may include some high intensity activities like landscaping) of 1.6 to 1.9, or Very Active (at least 60 minutes of daily walking or high intensity activity) of 1.9 to 2.5. Keep in mind, these activity factors don't include your specifically planned exercise, so an athlete isn't necessarily Very Active if they are only active during practice or events. This is similar to what MFP uses to determine your calorie needs daily, so the number you see on your profile is not really the BMR but more of a resting metabolic rate meaning only resting from your exercise routine and not completely at a level of bed rest.

After that calculation, then you add in your calories burned during planned exercise. We use the MET calculations for determining exercise calories because heart rate monitors calculations of calorie burns can be effected by medications, caffeine, improper programming for that individual, or an inaccurate formula if using an untested brand. From what I can tell doing some of my own calculations to double check them, MFP uses METs, too, for the calculations that they originally set up for exercise calories.

From the total of all of that, you should subtract no more then 20% to maintain your current muscle mass while losing body fat. Hence, the eat 80% of your total daily energy expenditure.

Now, I know that is a lot of math and very confusing in written form without a demo, so here is an example of how I figure calories for my clients and what we use in my EP program at school.

220 pound client, 25% body fat, works in an office where he has to walk around the office for meetings and show clients around maybe 30 to 45 minutes a day, todays workout is moderate weight training for 30 minutes followed by 30 minutes on the treadmill running at 5mph.

First we start by dividing 220 pounds by 2.2 to get 100 kg. Next we multiply the 100 kg by 25% to get 25 kg of body fat. Subtract the fat from the total body weight to get 100 - 25 = 75 kg of lean body mass.

75 x 24 = 1800 calories for the Basal Metabolic Rate. He should absolutely not go below this number.

His job would put him at the moderately active level, so we would then multiply the 1800 by 1.5 or 1.6. Typically, I've been taught to go to the middle of these zones and adjust up or down based on how the client responds, so I would use 1.55 as my multiplier. 1800 x 1.55 = 2790 calories per day. This is where MFP would then subtract out 500 or 1000 calories to give a daily calorie target which is why you eat your exercise calories from here because they aren't already figured in your needs before the deficit.

Now, we add in exercise calories. Moderate weight training would be 5.5 METs and a 5mph jog would be 8 METs. So to figure those calorie burns, we multiply the 100 kg person (because that is how much they are moving, not like what is metabolically active for determining calorie needs to maintain so we don't use lean body mass here) by the MET levels to get calories per hour. 100 x 5.5 = 550 calories per hour for the weight training and 100 x 8 = 800 calories per hour for the jogging. Divide them both in half since he only did a half hour of each to get 550/2 = 275 and 800/2 = 400. Add those together since he did both to get 675 calories burned in that hour of exercise. Add the 675 to the 2790 to get the total energy expenditure for today. 2790 + 675 = 3465.

Now, for weight loss while maintaining current muscle mass and energy level for the activities he does, multiply the TEE of 3465 by 80% (or by 20% and subtract it) to get a calorie goal. 3465 x 0.8 = 2772 calories he should consume that day to avoid losing muscle mass while losing weight.