So the Olympics are over, and one of this year’s most popular figures was, of course, Michael Phelps.  In addition to capturing the media’s attention for his record-breaking eight swimming gold medals, Michael’s diet was a major topic of discussion.  By some reports, Phelps consumed up to 12,000 calories/day eating egg sandwiches, pancakes, energy drinks, an entire pizza and a couple pounds of pasta.  Does this even seem possible? To address the issue, let’s consider the factors that influence how much athletes need to eat:

RMR: Each of us has a resting metabolic rate, which is the amount of calories the body needs to fuel its most basic functions – breathing, pumping blood, cell functioning, nutrient distribution, etc. This value varies from person to person and is affected by gender, size, and muscle mass.

Activity: Activity includes not only formal exercise but any movement.  This is where a lot of variation comes into play when we discuss the needs of different individuals.  Someone who works out for 60 minutes a day requires more energy than someone who sits at a desk all day.  Likewise, an athlete who works out six to seven hours per day (as is the case with Phelps) needs more fuel than an athlete working out only an hour a day.  There is an obvious economy of scale here.

Generally speaking, if our weight remains stable over time, we are doing a good job managing energy intake with energy expenditure.  If weight drops, we have created a calorie deficit, and if weight creeps up, we are in a calorie surplus.  Minor adjustments to food choices, exercise duration/intensity, and general movement can bring us back into balance.

Because of these factors, there is not a set amount of calories that an athlete should consume in a given day – it will vary considerably based on gender, size, muscle mass, sport, duration of activity, and season.  Here is my best advice:

• Each meal should look like this: mostly carbohydrates, some lean protein, healthy fat for flavor and texture, and lots of color (colorful meals have lots of vitamins and minerals – natural color that is!)
• Pay attention to the body’s natural cues and ask yourself, “Am I hungry? Am I full?”
• Monitor weight from time to time to determine whether or not you are meeting your specific goals.