If you know all that, you're a smart alec, but do you also know how many calories you've really left at the gym during your last resistance training workout? I can guarantee, it's not what your fitness tracker is telling you.
Learn more about alleged and true fat burner at the SuppVersity
Surprise #1: Most of the energy you spend during your resistance training sessions feeds into the aerobic (="cardio"), not the anaerobic (=sprint & lift) energy cycle
The first thing that may seem counter-intuitive is that the existing scientific evidence clearly indicates that, despite the predominance of anaerobic metabolism during the actual lifts, the largest part of the energy you spend during and after your gym sessions is spent aerobically.
Surprise #2: In response to strength training you burn hardly more energy than you would if you took your dog for the literally walk in the park.
As a SuppVersity reader this shouldn't be that surprising, but for a handful of bros who've always wondered why they're getting fat despite spending 2h in the gym on a daily basis, this may come as a revelation: the highest hitherto recorded energy expenditure during a resistance training workout is 8.3kcal/min that's significantly less than what you'd burn during a decently paced jog.
Surprise #3: A single rep burns hardly more extra calories than what your body requires to maintain its basal metabolic function
Likewise inaccurate is the assumption that you'd spend a lot of energy on the actual act of lifting a weight or, as it was the case for two out of three studies the results of which I've plotted for you in Figure 3, pushing it up on the bench.
As you can see, the energy expenditure per rep ranges from 0.42kcal/min to 1.99kcal/min and increases exponentially (you can see that in Scott 2009) with the amount of weight (relative to your one-rep max = 1RM) you lift.
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If you haven't done so already, read my ages-old article about "The Fallacy of Working Out To 'Burn Calories', Ladies & Gents" | more |
The good news is: You're not hitting the gym to "burn calories", anyway. If you want to lose body fat, diet! If you still think of your workouts as a means to make up for those three slices of pizza or the five bottles of beer, it's no wonder you're not happy with what you see in the mirror. Diet to lose body fat, lift heavy to maintain or even improve your hard earned muscle mass. That's the way it's done - irrespective of how many calories you burn in the gym and/or the hours after your workout | Comment!
References:
- Babiash, Paige E. Determining the energy expenditure and relative intensity of two Crossfit workouts. Diss. UNIVERSITY OF WISCONSIN-LA CROSSE, 2013.
- Campanholi Neto, Jose. "Demanda energética na sessão de exercício resistido com características de hipertrofia e resistência muscular localizada." (2015): 118-f.
- Gettman, Larry R., and Michael L. Pollock. "Circuit weight training: a critical review of its physiological benefits." The Physician and Sportsmedicine 9.1 (1981): 44-60.
- Kelleher, Andrew R., et al. "The metabolic costs of reciprocal supersets vs. traditional resistance exercise in young recreationally active adults." The Journal of Strength & Conditioning Research 24.4 (2010): 1043-1051.
- Magosso, Rodrigo Ferro, José Campanholi Neto, and João Paulo. "A Review of Ergogenesis and Effect of Training Variables on Energy Expenditure in Resistance Training Exercises." (2017).
- Mazzetti, Scott, et al. "Effect of explosive versus slow contractions and exercise intensity on energy expenditure." Medicine and science in sports and exercise 39.8 (2007): 1291.
- Ratamess, Nicholas A., et al. "The effect of rest interval length on metabolic responses to the bench press exercise." European journal of applied physiology 100.1 (2007): 1-17.
- Scott, Christopher B. "Contribution of blood lactate to the energy expenditure of weight training." The Journal of Strength & Conditioning Research 20.2 (2006): 404-411.
- Scott, Christopher B., Alicia Croteau, and Tyler Ravlo. "Energy expenditure before, during, and after the bench press." The Journal of Strength & Conditioning Research 23.2 (2009): 611-618.
- Scott, Christopher B., Michael P. Leary, and Andrew J. TenBraak. "Energy expenditure characteristics of weight lifting: 2 sets to fatigue." Applied Physiology, Nutrition, and Metabolism 36.1 (2010): 115-120.
- Scott, Christopher B., et al. "Aerobic, anaerobic, and excess postexercise oxygen consumption energy expenditure of muscular endurance and strength: 1-set of bench press to muscular fatigue." The Journal of Strength & Conditioning Research 25.4 (2011): 903-908.