Losing or gaining weight is a relatively simple process, yet people tend to complicate the process by looking for short cuts or easy ways out of hard work and discipline. Let me preface this article by saying that it is not actually easy, it is difficult and will require a great deal of will power and dedication to what is often a very slow process. If you’re looking to lose or gain ten pounds of bodyweight in a week then this article isn’t for you. This is for people who are serious about making a change and are willing to work hard to make it happen.
The most important factor in losing or gaining weight is calorie balance. That is, consuming either more or less calories than you are using each day. How do you know how many calories you are burning each day? Well, the gold standard for determining this is through Resting Metabolic Rate (RMR) testing via a metabolic cart which measures your caloric needs by assessing the amount of oxygen inhaled and carbon dioxide exhaled. This determines your RMR, which is the amount of calories you are expending at rest. However, since most individuals do not have access to or can’t afford this sort of testing the American College of Sports Medicine (ACSM) supports an equation, known as the Harris-Benedict Equation that can be used to give you a rough estimate. This equation uses you sex (male or female), height (cm), age (years), and weight (kg) to provide the estimate. The equations are as follows:
Male: (88.4 + 13.4 x weight) + (4.8 x height) – (5.68 x age) = Calories expended per day at rest.
Female: (447.6 + 9.25 x weight) + (3.10 x height) – (4.33 x age) = Calories expended per day at rest.
Again, remember we are using weight in kilograms, height in centimeters, and age in years. If you use height in inches and weight in pounds, aka freedom units, THIS WILL NOT WORK! And remember, this is only an estimate not an exact value.
Your RMR is NOT the total amount of calories you are burning per day. In fact, it is only one contributing factor. The total amount of calories an individual burns in a given day is known as Total Daily Energy Expenditure (TDEE) and it comes from several sources including RMR, the thermogenic effect of food (TEF), non-exercise activity thermogenesis (NEAT), excess post-exercise oxygen consumption (EPOC) and, of course, exercise (Ex).
TDEE = RMR + TEF + NEAT + EPOC + Ex
RMR and TEF are relatively constant from day to day with only small fluctuations due to muscle mass and conditioning, and to dietary shifts. The NEAT and exercise components (EPOC and Ex) have a much greater variability and can greatly influence you total daily caloric expenditure.
So how do we account for and determine for the NEAT and exercise components of TDEE?
Remember that equation we used for RMR? Well, you will simply take the number you found using that equation and multiply it by a given factor. What factor you multiply that by will vary based on how active you are in your everyday life.
1.2 = Sedentary (Desk job and little formal exercise)
1.3-1.4 = Lightly Active (Light daily activity and light exercise 1-3 days a week)
1.5-1.6 = Moderately Active (Moderately daily Activity and Moderate exercise 3-5 days a week)
1.7-1.8 = Very Active (Physically demanding lifestyle and Hard exercise 6-7 days a week)
1.9-2.2 = Extremely Active (Athlete in endurance training and/or very hard physically demanding job)
Be honest with yourself, if you’re sedentary then claim sedentary you won’t be hurting anyone but yourself. Oh and again, these are rough estimates based on an already estimated RMR so it is NOT 100% accurate.
Use the equations to find an estimate, stick to it for a week or two. If you gain weight in that time then your TDEE estimate is likely higher than your actual TDEE. Adjust by lowering the estimate by 250 calories per day and give it another try to week and see how that goes. Continue this until you find something pretty close to where you are maintaining your current weight. Likewise, if you lose weight in that time then you may need to up the estimated value by 250 calories or so per day and continue to adjust until you find where you are able to maintain your weight at.
Now that you know how many calories you need to maintain your weight it’s time to either lose or gain weight. If you want to lose weight then you need to consume less calories than is required for maintenance to be in a caloric deficit. And likewise if you are trying to gain weight then you need to consume more calories than you are expending to be in a caloric surplus.
How big of a deficit or surplus should I be in per day? That’s not a very easy question to answer. Some have more weight to lose than others. So if you’re over 20% body fat then it may be a good idea to be in a larger caloric deficit than someone who is already relatively lean and under 20% body fat. Keep in mind that 20% is not a magical number, I’m just using this as an example but be real with yourself if you are obese or very overweight then you know it, likewise if you are very underweight you are also aware of this and know you should probably be trying to gain weight faster than the typical person. So where should you start? I would suggest starting out at no more than a 500 calorie per day deficit/surplus, this will set you up to lose/gain right around 1 pound of body weight per week. This is a pretty safe amount to lose or gain and still stay healthy. However, if you are very overweight or very underweight than I would suggest you start with a larger surplus or deficit of around 1,000 calories per day.
Calorie balance is a great start to either losing or gaining body weight. This article has given you sufficient information to get you on the right track towards weight management. In the next installment I will dig a little deeper into this topic and cover macronutrient (protein/fat/carbohydrate) intake.