Properly Fueling Your Workouts Part I: Calorie Goals

Properly Fueling Your Workouts: Calorie Goals, Part One

By: Samantha McCarthy MS, RD/LDN

Last night I offered a free lecture on properly fueling your workouts. Over the next few weeks, I’d like to break down some of the components of that lecture to share with you all. This will be a 3-part series starting off with calorie goals.

Why do you need to properly fuel your workout? There are many reasons. In our country, we are fortunate that food is overly available. Very few of us (luckily) are food secure, but this has created an issue. We have forgotten the purpose of food, which is to provide us with fuel and nutrients. We can’t live without it. But the availability of food has made food more of a hobby or coping mechanism that actual fuel. This is more of an issue for those of us who are regularly active.

Exercise requires a lot of our bodies. If we don’t properly fuel them, many problems can arise. You can have a slow, sluggish performance/workout, digestive upset, inadequate recovery, higher risk of injury and dehydration. Properly fueling your workouts can make a world of difference. You could have less muscle soreness, improved recovery time, better performance, more energy, and better results. Now, some of you may be thinking, “well I feel completely fine during my workouts.” But how do you know that can’t feel better? You may be so used to how you feel that it seems normal to you.

Proper fueling for your workouts start with the appropriate amount of calories. Too many calories can make you feel sluggish, too few calories can make you feel weak. You want to find the appropriate balance for your body. One of the common ways to calculate calorie needs is using the Harris-Benedict Equation:

  • Women:  655 + ( 4.35 x weight in pounds ) + ( 4.7 x height in inches ) - ( 4.7 x age in years )

  • Men: 66 + ( 6.23 x weight in pounds ) + ( 12.7 x height in inches ) - ( 6.8 x age in years )

Plug in all of your values and then you will get what’s called your resting metabolic rate (RMR). This is your baseline. From there, you want to add on your activity. Take you RMR and multiply it by the activity level (as outlined below) and you will get your total calorie needs.


Little or No exercise


Lightly Active

Light Exercise 1-3 days per week


Moderately Active

Moderate Exercise 3-5 days per week


Very Active

Hard Exercise 6-7 days per week


Extra Active

Very Hard Exercise and/or Physical Job


And that is how you figure out your calorie needs! Next week we will discuss your macronutrient needs!