It is easy to be confused by the flood of information that circulates about weight management. For a long time, the mantra has been “eat less; move more”. Some, however, challenge this. So, what is one to believe?
I believe in the K.I.S.S. principle when it comes to exercise. This is not to say that the physiology of exercise is inherently simple.
On the surface, “eat less; move more” is merely a reflection of the caloric balance equation (calories in v. calories out). This is quite simple, but also complex. It suggests that weight management is as simple as counting calories. It is not. (But, it also is.)
Caloric needs are the net effect of basal metabolic effect, the thermogenic effect of food, and physical activity. Basal metabolic rate (BMR; the energy required of the body to maintain bodily functions) is not perfectly static and can vary because of far too many variables to worry about. Thermogenic effect of food (usually 5-10% of the daily caloric needs) also varies according to the food combinations being eaten. It is also too challenging to waste excess energy on (pun intended). Physical activity is the variable over which we have the most actual control, but it also not measured perfectly. We can estimate our daily energy expenditure, but it will always be at best just an estimate. So, we must look at caloric needs as an average over time. We should think about calories relative to the average body weight. If our average weight is going up over time, we are hypercaloric. If we are losing weight, we are hypocaloric. If we are maintaining weight, we are, then, eucaloric.
“Eat less; move more” is not mutually inclusive. It is actually possibly detrimental to think as a such. Often one who is seeking to lose weight judges progress according to the scale alone. If weight is not changing such people cut calories more and ramp up the exercise. This isn’t always beneficial. The result is often weight loss, but not necessarily productive weight loss. It is mostly water, and often muscle weight.
The maintenance of muscle mass is most important to effective management of body composition. This requires effective exercise (i.e., resistance training) and adequate calories to fuel performance. In such a case, the mantra might be stated better as “eat appropriately; move effectively”. The principles of specificity and progressive overload apply. Depending on the starting point, the necessary changes to caloric intake and/or expenditure will vary. If one is overfat and under-muscled, a modest caloric restriction can permit fat loss in addition to muscle gain. In such a case, the scale is going to be a poor indicator of body composition changes. If one is lean and muscled, calories should be carefully managed to affect the desired change—a modest increase to support a muscle gain and a modest decrease to body fat.
Because there are numerous factors that affect BMR on a daily and long-term basis and the calories expended during exercise are not regularly measured directly, counting calories is only minimally effective for weight management. It can be tedious and effort can be better served focusing on portion sizes and macro balance. Counting portions and considering day-to-day changes in activity afford more consideration.
Be your best today; be better tomorrow.
Carpe momento!