Shortcomings of Exercise-a Holiday Tale

“Whoa, I’m passing a Starbuck’s. I think I’ll just drop in for my favorite Starbuck’s drink; the 16 oz. ‘Peppermint White Hot Chocolate’ with whipped cream. I know it’s a few extra calories, but I’m going to the gym and I’ll burn it off on the elliptical trainer.”  Our fictional Starbuck’s lover has just ingested 490 calories; and more if he asks for whole milk. He is a “casual” gym-goer and does only 30 minutes on the elliptical at a moderate pace and resistance level. Let’s examine the effectiveness of his elliptical trainer work-out to offset those 490 calories.

 For starters, due to his casual acquaintance with the elliptical, our protagonist will be fortunate to crank out a reading of 300 calories burned in his 30 minutes of elliptical work. That leaves him 190 calories short of burning off his Starbuck’s caloric load. But, there is a lot more to the story. Let’s look at the calories-burned reading on the elliptical. Although it reads 300 calories burned, reality may not be so generous. Sources indicate that elliptical machines can overestimate calories-burned by 30% to 50%.

So far, not so good. If we use the lower of the above estimates of a 30% overestimate, our hero is now down to only 210 calories consumed by his work-out. However, there are two more issues we should consider.

1. The Basal Metabolic Rate (BMR) is the number of calories our bodies burn at rest to maintain normal body functions. The problem involving the elliptical and the BMR is that the displayed 300 calories burned are not calories burned above our hero’s BMR; they represent calories burned including his BMR. If we assume our elliptical jockey is 35 years old, 5’ 10” tall and weighs 185 pounds, his BMR for 30 minutes would be about 40 calories. He would burn these 40 calories just by lying on the sofa. So, we need to subtract them from the calories burned on the elliptical. We are now down to an effective 170 calories burned on the elliptical.

1. Our elliptical man performs a steady-state, relatively low-intensity routine in achieving his 30 minutes on the trainer. This type of exercise can cause him to lose muscle, since he uses such a small percentage of his muscle mass to perform his elliptical work. His body can perceive any additional muscle as dead weight; useless and burdensome. Since muscle burns more calories than does fat (the magnitude of which is arguable) any loss of muscle further diminishes the value of steady-state, low-intensity exercise. “A person who persists in seven days per week of steady-state training, could, over the course of six-months to a year, easily lose about five pounds of muscle tissue.” Doug McGuff, MD, John Little, Body by Science..

Beyond the caloric content of the drink, there are the negative effects of the 62 grams of sugar and 199 calories from the not-so-good saturated fat in this drink! This brings us full circle to our basic nutritional belief, “We can’t out-exercise a bad diet.”  Holiday time caloric indulgence usually leads to an addition to our body fat percentage, which is not often reversed. While any physical movement is good, it may not be effective in countering caloric over-consumption.