A big weight loss myth that just won’t go away! The biggest culprit that feeds this myth is the misconception that it’s as simple as “calories in vs. calories out.”
Now, you may need to eat less and you may need to move more, there is absolutely a time and a place for this. So what happens when you do eat less, and do start to move more? Well, that only works for so long, and then what? What happens when you cannot eat any less or exercise any more? You’re stuck.. That’s what happens! Under-eating can have similar outcomes to over-eating and be just as detrimental to your health!
This study shows how more activity does NOT always mean we are burning more calories over the course of a day. At a certain point, energy expenditure plateaus and adaptations begin to take place, slowing down the energy expended on bodily functions… in other words, it’s all a wash!
You may burn 100 extra calories by extending your run, but that may in turn decrease your energy expenditure from non-exercise and overall movement (NEAT - Non Exercise Activity Thermogenesis) by moving around less because you’re more tired, in addition, your body may begin to shut down bodily processes that aren’t absolutely necessary to survival. Neither of these are good and ultimately result in no more calories being burned than had you not increased your run time to begin with.
In an article written for The Cut, it is said that, “We’ve been conditioned to believe that exercise plays a bigger role in weight loss than it really does. Writing recently for Vox, Julia Belluz and Christophe Haubursin note that ‘while your food intake accounts for 100 percent of the energy that goes into your body, exercise only burns off less than 10 to 30 percent of it.’ In fact, findings from a 2013 review of studies suggest that people tend to overestimate how many calories they burn via exercise, and make up those calories and then some with yummy foods (read: doughnuts). Exercise does wonders for your mood and your brain and has a host of other health benefits, but it’s not (and shouldn’t be) the main driver of weight loss.”
The research on this subject is extensive... with good reason...
“There can be no doubt that changes in the availability of food, and its increased caloric content, have played a major role in the obesity epidemic. It follows that public health advice has been to reduce food intake, although there has been limited success. Unfortunately, although the high level of calorie intake was a large part of the initial problem, it does not follow that its reduction will be a major part of the solution. When a reduction in calorie intake has decreased body weight, there are powerful physiological adaptations that favor regaining that weight (Greenway, 2015). When the initial attention associated with attempting to lose weight dissipates, body weight increases and returns to, or even exceeds, the starting level (Mann et al., 2007).” (2)
“Those maintaining a low weight often use cognitive strategies to prevent compensatory increases in calorie consumption. Those who put on weight may be unaware of psychological strategies or may choose not to use them….If there is no conscious control of calorie intake, the body will simply replace the lost energy.
In addition, it is unlikely that minor changes in diet will reduce the incidence of obesity, as controlling body weight will often require a complete dietary makeover. It does, however, seem likely that concentrating on the nature of the food consumed, rather than simply reducing calories, offers advantages. An approach that considers macro-nutrients, energy density, and glycemic load may help to prevent energy compensation.”(2)
Check out this full article, titled "Reducing Calorie Intake May Not Help You Lose Body Weight," here.
“Ensuring maintenance of weight loss is a crucial step in reversing the current and alarming rise in obesity and, hence, reducing the burden of obesity-related comorbidities. Restricting food intake through dieting generally leads to successful short-term weight loss, but, over the long term, many individuals regain the lost weight. Individuals who live in an ‘obesogenic' environment encounter opportunities to overeat on a regular basis. Moreover, compensatory physiological adaptations following diet-induced weight loss, such as decreases in energy expenditure, fat oxidation and anorexigenic hormone (for example, leptin) levels and increases in appetite, craving and orexigenic hormone (for example, ghrelin) levels, promote weight regain. There is also increasing evidence regarding the role of other factors, including hedonic factors and glial cell activity, in overriding the normal feedback loop controlling body weight.
In order to maintain a healthier weight, individuals must adhere to obesity-reducing behaviours that counteract physiological adaptations and other factors associated with weight regain.”(3)
Check out this full article, titled "Physiological Adaptations to Weight Loss and Factors Favouring Weight Regain," here.
References
1. Belluz, Julia, and Christophe Haubursin. “The Science Is in: Exercise Won't Help You Lose Much Weight.” Vox.com, Vox Media, 2 Jan. 2019, www.vox.com/2018/1/3/16845438/exercise-weight-loss-myth-burn-calories.
2. Benton, David and Hayley A Young. “Reducing Calorie Intake May Not Help You Lose Body Weight” Perspectives on psychological science : a journal of the Association for Psychological Science vol. 12,5 (2017): 703-714.
3. Greenway, F L. “Physiological adaptations to weight loss and factors favouring weight regain” International journal of obesity (2005) vol. 39,8 (2015): 1188-96.
4. Lee, Stephanie. “The Advice to 'Eat Less, Move More' Perpetuates Myths About Weight Loss.” The Cut, The Cut, 24 July 2017, www.thecut.com/2017/07/eat-less-move-more-perpetuates-myths-about-weight-loss.html.
5. Mann T., Tomiyama A. J., Westling E., Lew A. M., Samuels B., Chatman J. (2007). Medicare’s search for effective obesity treatments: Diets are not the answer. American Psychologist, 62, 220–233.
6. Pontzer, Herman et al.
Current Biology , Volume 26 , Issue 3 , 410 - 417. Constrained Total Energy Expenditure and Metabolic Adaptation to Physical Activity in Adult Humans.
7. Thomas, D M et al. “Why do individuals not lose more weight from an exercise intervention at a defined dose? An energy balance analysis” Obesity reviews : an official journal of the International Association for the Study of Obesity vol. 13,10 (2012): 835-47.
Tags
コメント