{"id":34575,"date":"2023-07-18T01:57:00","date_gmt":"2023-07-18T01:57:00","guid":{"rendered":"https:\/\/www.lifeandnews.com\/articles\/?p=34575"},"modified":"2023-07-19T18:37:29","modified_gmt":"2023-07-19T18:37:29","slug":"exercise-may-or-may-not-help-you-lose-weight-and-keep-it-off-heres-the-evidence-for-both-sides-of-the-debate","status":"publish","type":"post","link":"https:\/\/www.lifeandnews.com\/articles\/exercise-may-or-may-not-help-you-lose-weight-and-keep-it-off-heres-the-evidence-for-both-sides-of-the-debate\/","title":{"rendered":"Exercise may or may not help you lose weight and keep it off \u2013 here\u2019s the evidence for both sides of the\u00a0debate"},"content":{"rendered":"\n<p><a href=\"https:\/\/theconversation.com\/profiles\/donald-m-lamkin-1439709\">Donald M. Lamkin<\/a>, <em><a href=\"https:\/\/theconversation.com\/institutions\/university-of-california-los-angeles-1301\">University of California, Los Angeles<\/a><\/em><\/p>\n\n\n\n<p>The global fitness industry will generate <a href=\"https:\/\/www.wellnesscreatives.com\/fitness-industry-statistics-growth\/\">over US$80 billion in revenue<\/a> in 2023, estimates suggest. And why not, given the many excellent <a href=\"https:\/\/www.cdc.gov\/nccdphp\/sgr\/index.htm\">reasons to exercise<\/a>? Better cardiovascular health, lower risk of Type 2 diabetes, stronger immune system \u2013 the list goes on.<\/p>\n\n\n\n<p>One of the biggest reasons many people choose to exercise is to <a href=\"https:\/\/www.better.org.uk\/content_pages\/top-gym-excuses\">lose weight<\/a>. As a <a href=\"https:\/\/www.semel.ucla.edu\/profile\/donald-m-lamkin-phd\">biobehavioral scientist<\/a>, I study links between behavior and health, and I heed the time-honored advice that eating less and exercising more are necessary to lose weight. But a <a href=\"https:\/\/doi.org\/10.1038\/s41366-022-01247-4\">recent debate<\/a> in the scientific community highlights the growing suspicion that the \u201cexercising more\u201d part of this advice may be erroneous.<\/p>\n\n\n\n<p>At the center of the debate is the <a href=\"https:\/\/doi.org\/10.1038\/s41366-022-01248-3\">constrained total energy expenditure hypothesis<\/a>, which asserts that exercise won\u2019t help you burn more calories overall because your body will compensate by burning fewer calories after your workout. Thus, exercise won\u2019t help you lose weight even if it will benefit your health in countless other ways.<\/p>\n\n\n\n<p>Obesity researchers <a href=\"https:\/\/doi.org\/10.1038\/s41366-022-01234-9\">take issue with this<\/a> hypothesis, because it\u2019s based on observational research rather than randomized controlled trials, or RCTs, the gold standard of scientific evidence. In RCTs, participants are randomly assigned to either a treatment or a control group, which allows researchers to determine whether the treatment causes an effect. Randomized controlled trials have shown that exercise causes weight loss.<\/p>\n\n\n\n<p>The verdict is actually more mixed when considering all the gold-standard evidence available. https:\/\/www.youtube.com\/embed\/wWGulLAa0O0?wmode=transparent&amp;start=0 Exercise provides many health benefits.<\/p>\n\n\n\n<h2>What the evidence says<\/h2>\n\n\n\n<p>Spectators of this hypothesis have <a href=\"https:\/\/doi.org\/10.1038\/s41366-022-01247-4\">emphasized the importance<\/a> of systematically reviewing the evidence from all gold-standard trials. They pointed to a 2021 review of more than 100 exercise studies that examined the effect on weight loss in adults of aerobic, resistance or high-intensity interval training in combination or alone. The review concluded that supervised exercise regimens do <a href=\"https:\/\/doi.org\/10.1111\/obr.13256\">cause weight loss<\/a>, even if only a modest amount.<\/p>\n\n\n\n<p>So that settles the debate, yes? If you eat too much dessert, then you can just go on an extra run to burn off those extra calories, right?<\/p>\n\n\n\n<p>Well, not exactly.<\/p>\n\n\n\n<p>If extra physical exertion burns extra calories overall, then exercise should also keep the weight from coming back after low-calorie dieting. But keeping those lost pounds off after dieting is a common challenge. The <a href=\"https:\/\/doi.org\/10.1111\/obr.13256\">same 2021 review<\/a> includes the few randomized controlled trials that address the question of whether exercise facilitates weight maintenance. However, the results weren\u2019t as good as they were for weight loss. The researchers found that six to 12 months of aerobic exercise, resistance training or both after dieting did not prevent weight regain in adults.<\/p>\n\n\n\n<h2>Exercise adherence<\/h2>\n\n\n\n<p>But what about compliance? Did all the people in those studies actually exercise regularly?<\/p>\n\n\n\n<p>The 2021 review found only one randomized controlled trial on weight maintenance that <a href=\"https:\/\/doi.org\/10.1016\/j.physbeh.2018.03.014\">reported an objective compliance rate<\/a>, meaning each exercise session was supervised by a trainer. This tells us the percentage of time that participants in the study actually exercised as prescribed.<\/p>\n\n\n\n<p>In that trial, the compliance rate was only 64% for 25 post-menopausal women who completed a resistance training program after diet-induced weight loss. This was for a regimen in which participants had to come in and exercise two to three times per week for an entire year. From the perspective of keeping up with a program for that long, doing so 64% of the time doesn\u2019t seem so bad.<\/p>\n\n\n\n<p>But they still gained back as much weight as the 29 women in the control group who were not enrolled in the exercise program.<\/p>\n\n\n\n<figure class=\"wp-block-image\"><a href=\"https:\/\/images.theconversation.com\/files\/536893\/original\/file-20230711-16-wdudrx.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=1000&amp;fit=clip\"><img src=\"https:\/\/images.theconversation.com\/files\/536893\/original\/file-20230711-16-wdudrx.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;fit=clip\" alt=\"Feet standing on a digital scale\"\/><\/a><figcaption>Keeping off the pounds after losing them can be challenging. <a href=\"https:\/\/www.gettyimages.com\/detail\/photo\/top-down-view-of-feet-standing-on-white-digital-royalty-free-image\/1324553412\">OsakaWayne Studios\/Moment via Getty Images<\/a><\/figcaption><\/figure>\n\n\n\n<h2>Energy balance<\/h2>\n\n\n\n<p>Many people would say that it\u2019s all about balancing energy in from food and energy out from exercise. If exercise didn\u2019t keep the weight off, then maybe a bigger dose of exercise was needed.<\/p>\n\n\n\n<p>The American College of Sports Medicine highlighted this issue of exercise dose in its <a href=\"https:\/\/doi.org\/10.1249\/MSS.0b013e3181949333\">2009 position statement<\/a> on physical activity for weight maintenance, stating that the amount of physical activity needed for weight maintenance after weight loss is uncertain. Moreover, it stated that there is a lack of randomized controlled trials in this area that use state-of-the-art techniques to monitor the energy balance of participants.<\/p>\n\n\n\n<p>Fortunately, some of the authors of the position statement went on to use state-of-the-art techniques to monitor energy balance in their own randomized controlled trial. In 2015, they enrolled overweight adults into a 10-month aerobic exercise program and compared the energy intake of those who lost weight with the energy intake of those who didn\u2019t lose weight while on the program. They found that those who didn\u2019t lose weight were indeed <a href=\"https:\/\/doi.org\/10.1002\/oby.21073\">taking in more calories<\/a>.<\/p>\n\n\n\n<h2>Mystery of the disappearing calories<\/h2>\n\n\n\n<p>But there\u2019s something else in that 2015 study\u2019s <a href=\"https:\/\/doi.org\/10.1249\/MSS.0000000000000354\">energy measurements<\/a> that is quite interesting. By the end of the study, the number of total daily calories the exercisers burned was not significantly different from what the nonexercisers burned. And this was in spite of the fact that trainers verified the exercisers burned an extra 400 to 600 calories per session at their nearly daily exercise sessions. Why didn\u2019t those extra exercise calories show up in the total daily calories burned?<\/p>\n\n\n\n<figure class=\"wp-block-image\"><a href=\"https:\/\/images.theconversation.com\/files\/536901\/original\/file-20230711-24-pufhjl.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=1000&amp;fit=clip\"><img src=\"https:\/\/images.theconversation.com\/files\/536901\/original\/file-20230711-24-pufhjl.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=237&amp;fit=clip\" alt=\"Kettle ball crushing a bagel\"\/><\/a><figcaption>Weight loss isn\u2019t as simple as energy in, energy out. <a href=\"https:\/\/www.gettyimages.com\/detail\/photo\/kettle-bell-smashing-a-bagel-royalty-free-image\/852156500\">Shana Novak\/Digital Vision via Getty Images<\/a><\/figcaption><\/figure>\n\n\n\n<p>The answer to that question may help explain why exercise doesn\u2019t always help you keep the weight off: Your metabolism responds to regular exercise by decreasing the number of calories you burn when you\u2019re not exercising. That\u2019s according to the <a href=\"https:\/\/doi.org\/10.1038\/s41366-022-01248-3\">constrained total energy expenditure hypothesis<\/a> that spurred the current debate.<\/p>\n\n\n\n<p>Researchers recently tested the hypothesis by measuring the nonexercise calorie burn of 29 obese adults over a nearly 24-hour period, both before and after a six-month exercise program. They found that the calories they burned when they weren\u2019t working out did <a href=\"https:\/\/doi.org\/10.1249\/MSS.0000000000002689\">decrease after months of regular exercise<\/a> \u2013 but only in those who were prescribed the higher of two different exercise doses.<\/p>\n\n\n\n<p>Those who exercised at the lower dose for general health, meaning they burned an extra 800 to 1,000 calories per week, saw no change in their metabolic rate. But those who exercised at the higher dose to lose weight or maintain weight loss, meaning they burned an extra 2,000 to 2,500 calories per week, had a decrease in their metabolic rate by the study\u2019s end.<\/p>\n\n\n\n<h2>Exercise for health<\/h2>\n\n\n\n<p>Perhaps both sides of the debate are right. If you want to lose a modest amount of weight, then a new exercise routine might make a modest contribution toward meeting that goal.<\/p>\n\n\n\n<p>However, as others have said, don\u2019t fool yourself into thinking you can \u201c<a href=\"http:\/\/dx.doi.org\/10.1136\/bjsports-2015-094911\">outrun a bad diet<\/a>\u201d by simply exercising more. There is a diminishing marginal return to exercise \u2013 you eventually take less weight off for the additional exercise you put in.<\/p>\n\n\n\n<p>But even if extra exercise might not help you lose weight and keep it off, there are still the other great <a href=\"https:\/\/www.cdc.gov\/nccdphp\/sgr\/index.htm\">health dividends<\/a> that regular exercise pays out.<\/p>\n\n\n\n<p><a href=\"https:\/\/theconversation.com\/profiles\/donald-m-lamkin-1439709\">Donald M. Lamkin<\/a>, Assistant Professor of Psychiatry and Biobehavioral Sciences, <em><a href=\"https:\/\/theconversation.com\/institutions\/university-of-california-los-angeles-1301\">University of California, Los Angeles<\/a><\/em><\/p>\n\n\n\n<p>This article is republished from <a href=\"https:\/\/theconversation.com\">The Conversation<\/a> under a Creative Commons license. Read the <a href=\"https:\/\/theconversation.com\/exercise-may-or-may-not-help-you-lose-weight-and-keep-it-off-heres-the-evidence-for-both-sides-of-the-debate-207457\">original article<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Donald M. Lamkin, University of California, Los Angeles The global fitness industry will generate over US$80 billion in revenue in 2023, estimates suggest. And why not, given the many excellent reasons to exercise? Better cardiovascular health, lower risk of Type 2 diabetes, stronger immune system \u2013 the list goes on. One of the biggest reasons [&hellip;]<\/p>\n","protected":false},"author":44,"featured_media":34576,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[42],"tags":[8820,9230,4235,137,14396,7473,935,3285,14397,3797],"_links":{"self":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts\/34575"}],"collection":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/users\/44"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/comments?post=34575"}],"version-history":[{"count":2,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts\/34575\/revisions"}],"predecessor-version":[{"id":34585,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/posts\/34575\/revisions\/34585"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/media\/34576"}],"wp:attachment":[{"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/media?parent=34575"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/categories?post=34575"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lifeandnews.com\/articles\/wp-json\/wp\/v2\/tags?post=34575"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}