This week we're talking energy balance! When you start looking at numbers -- calories (kcal), grams, percentages -- it can all get very confusing. But the concept of energy balance is pretty simple.
If you eat and drink basically the same amount of calories that you are expending in a day, you’ll maintain your weight.
If you eat and drink less than you are expending, you’ll lose weight (fat and/or lean mass).
If you eat and drink more than you are expending, you’ll gain weight (fat and/or lean mass).
Your food/drink intake includes ALL energy taken in, both off and on the bike. Your energy expenditure includes ALL energy output, both off and on the bike.
Estimate your daily energy needs or the calories you need to take in daily
If you can’t get to a lab to measure your Resting Metabolic Rate, you can use one of the evidence-based equations to estimate your energy needs at rest. I have provided one to all BaseCamp Pro members, but if you’re not a Pro member, you can easily find a calculator online that can give you an estimate. Then, you’ll do one of two things:
Take the kcal expended during your ride (grab the data from TrainingPeaks) and add those to your estimated calorie needs for a sedentary or rest day. If your estimated needs were 2000 kcal for a rest day and you burn 1000 kcal during your ride, you’ll want to eat 3000 kcal if your goal is maintenance. OR
Multiply your estimated calorie needs at rest by an activity factor depending on how physically active you are or how hard your training is that day (x 1.3 to x 1.9). That equals the estimated total you’ll need to eat for maintenance. Sometimes this estimate can be on the lower side if you were to compare your actual energy utilization using power data. So you may use this estimate for your daily energy intake off the bike and then add your 30-60 g carbohydrate per hour of your training ride on top of that. This may take some trial and error.
How do you know if you’re eating enough, too little, or too much?
Weigh yourself periodically. If you’re maintaining, you’re eating an adequate amount for your training load. If you’re losing weight, you’re eating less, and if you’re gaining weight, you're overeating for your training load. What you should be doing really depends on your goals. If you want to lose fat mass, I suggest eating an overall calorie deficit of up to ~20% over the course of each week. If you try to restrict energy intake more than that, you’ll risk overtraining and also losing lean mass rather than fat mass.
Should you track your intake?
If you're new to this, I think it's okay to track your intake for a few days as you get started. However, the practice of food tracking is very cumbersome as a daily activity and can lead to disordered eating habits. Instead, once you have a handle on the portion sizes you should be taking in, track these metrics instead:
Body weight and body composition using a BIA scale
General mood and feelings of energy
Perceived recovery from training
Daily feelings of hunger (are you starving every evening?)
Menstrual cycle and changes
And remember... just like with training, consistency is the key when it comes to making sustainable diet changes. If your habits are too strict for you to be consistent, you may want to reevaluate your intake and your goals!
About the Author
Dr. Namrita Brooke began her coaching practice while a doctoral student. Today she is a full time coach and nutritionist, and she runs an online group program called Fueling Fat Loss. She is also a cycling coach and the head nutritionist with Velocious Cycling Adventures. Her personal athletic experience ranges from endurance mountain biking to off-road triathlon, cross-country mountain bike racing, running, road cycling, duathlon, and cyclocross. Her research background includes hydration and sports drink research, and the interaction of nutrition, physical activity, and the brain.