Thursday, January 23, 2014

Do We Systematically Underestimate the Energetic Costs of Push-Ups, Pull Ups, Squats & Co? Study Says Anaerobic Exercises Burn 2x More Energy Than Previously Thought

If we go by the data from the Verzina study, push-ups and pull-ups burn 50% and 62% more energy than we previously thought they would. Against that back- ground it's no wonder that participants in the Smith study (more), I wrote about pre- viously got from 16% to 8% body fat.
"Do We Systematically Underestimate the Energy Expenditure During Anaerobic Activities?", that's not just the question the headline of today's SuppVersity article eventually implies, it is also an essential question with a potentially consequential answer I came up with, when I read a recent paper by scientists from the Department of Exercise and Wellness at the Arizona State University (Vezina. 2014).

The said paper presents an examination of the differences between two methods of estimating energy expenditure in resistance training activities and concludes that (a) "the methods we use to calculate the EE of anaerobic activities significantly affects EE estimates" and (b) that this leads to a significant underestimation of the energetic costs of anaerobic activity if we use the traditional methods.

What is the traditional method anyway?

"Traditional" in this context means using calorimetry to measure oxygen uptake continuously throughout the trial. "Oxygen uptake" and "anaerobic activity" - when you come to think about it, it should be obvious that this does not really go together. The former is after all specifically high, when you perform "aerobic" not anaerobic activities. including the recovery period between exercises.

In spite of the fact that it is questionable, whether the alternative the scientists used, i.e. measuring the oxygen uptake during recovery, instead of during activity, is actually "accurate", it goes without saying that the real world health benefits and weight loss results people achieve, when they lift heavy weights or perform high intensity interval training would support the notion that the de facto energy expenditure could have been significantly underestimated.
Figure 1: Energy expenditure (kcal per kg of body weight per hour) due to body weight exercises calculated based on oxygen uptake during the exercises (traditional) or during the rest periods (improved; Vezina. 2014)
And if we assume that the data Vezina et al. collected in their experiment with twelve healthy men (mean age: 23.6 ± 2.84 years [range 18-29 years]; mean body mass index (BMI): 24.63 ± 2.63; mean percentage of body fat: 12.03 ± 4.44%; non-Hispanic white n=9) is correct, this difference will be as significant, as the average 49% difference you can see in my plot of the data the scientists measured in their in Figure 1.

For Mr. Average Joe with a body weight of 80kg, this would mean that his 30 minutes body weight workout doesn't consume 288kcal, but 576kcal and thus way more than 30min of jogging, which should cost him ~400kcal.
Suggested Read: "The Fallacy of Working Out To Burn Calories + Exercise Shuts Down the Carb Cravings" | read more
Bottom line: I guess I don't have to tell you that these results are very important. Not for you, obviously, because you as a SuppVersity reader know about the fallacy of working out to burn energy, but for all those Average Joes and specifically Janes out there who still believe that you'd lose weight by simply burning all the junk you eat off in the gym.

Cardio "addicts" would yet not be the only ones for whom these results - if they turn out to be substantial - would have huge consequences. The average "expert" on the panels we owe the wise dietary and exercise guidelines to, would probably also have to revise his opinion on the primary of "cardio" exercise for its "superior ability to help shed weight"... unfortunately, my gut tells me that I am the only one who even noticed the (future) publication of this paper in the Journal of Strength and Conditioning.
  • Vezina, Jesse W., et al. "An Examination of the Differences Between Two Methods of Estimating Energy Expenditure in Resistance Training Activities." Journal of strength and conditioning research/National Strength & Conditioning Association (2014).