{"id":418776,"date":"2026-01-17T09:16:27","date_gmt":"2026-01-17T09:16:27","guid":{"rendered":"https:\/\/www.newsbeep.com\/au\/418776\/"},"modified":"2026-01-17T09:16:27","modified_gmt":"2026-01-17T09:16:27","slug":"why-exercise-doesnt-burn-more-calories-and-why-thats-not-the-point","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/au\/418776\/","title":{"rendered":"Why exercise doesn\u2019t burn more calories \u2014 and why that\u2019s not the point"},"content":{"rendered":"

Herman Pontzer, PhD, an evolutionary anthropologist at Duke University, investigates how the human body expends energy \u2014 and how those metabolic limits help shape health and longevity. (Photos by Eamon Queeney)<\/p>\n

From primate biology to modern weight loss debates, Herman Pontzer, PhD, traces how evolution shaped a metabolism built for movement, adaptation, and survival <\/p>\n

Evolutionary anthropologist\u00a0Herman Pontzer, PhD<\/a>,\u00a0thought he knew what\u00a0he\u2019d\u00a0find when he traveled to Tanzania to live among the\u00a0Hadza, one of the last remaining hunter-gatherer communities on Earth.\u00a0\u00a0<\/p>\n

The Hadza walk miles<\/a>\u00a0each day across the dry savannah, hunting game and gathering roots,\u00a0berries,\u00a0and honey. Surely, Pontzer figured,\u00a0they\u00a0must\u00a0burn more calories than sedentary Americans.\u00a0\u00a0<\/p>\n

He was wrong.\u00a0\u00a0<\/p>\n

After weeks of collecting urine samples and tracking physical activity, the results stunned him: the\u00a0Hadza\u00a0burned about the same number of calories per day as people in the United States who spend most of their time sitting.\u00a0\u00a0<\/p>\n

That finding \u2014 later confirmed in other\u00a0hunter-gatherers\u00a0and industrialized\u00a0populations \u2014 upended conventional wisdom about exercise and energy use. It also launched Pontzer,\u00a0a\u00a0faculty member in the\u00a0Duke Global Health Institute<\/a>,\u00a0into the center of a scientific rethink about metabolism, aging,\u00a0and what it means to be human.\u00a0\u00a0<\/p>\n

The metabolic budget\u00a0<\/p>\n

Pontzer\u2019s research\u00a0suggests that the human body\u00a0operates\u00a0on a fixed energy budget. When we ramp up physical activity, the body compensates by\u00a0dialing down\u00a0energy spent elsewhere \u2014 on immune function, reproduction, even stress responses.\u00a0\u00a0<\/p>\n

That\u2019s\u00a0why exercise\u00a0doesn\u2019t\u00a0translate into the calorie-burning bonanza many expect.\u00a0\u00a0<\/p>\n

But that\u00a0doesn\u2019t\u00a0mean exercise is unimportant. In fact, those\u00a0trade-offs\u00a0may explain why exercise is so good for us. Regular movement lowers chronic inflammation, stabilizes hormones, and reduces risk for diseases from cancer to heart disease.\u00a0\u00a0<\/p>\n

\u201cYou have to think about diet and exercise as two different tools for two different jobs,\u201d said Pontzer. \u201cDiet is the tool for managing your weight. Exercise is the tool for everything else related to health \u2014 from mental health to cardiometabolic disease.\u201d\u00a0\u00a0<\/p>\n

Evolution\u2019s blueprint\u00a0\u00a0<\/p>\n

An author and mentor, Pontzer is shaping global conversations about how humans expend energy, with work widely regarded as among the field\u2019s most influential science writing.<\/p>\n

From an evolutionary perspective, the pattern makes sense: our ancestors needed to walk long distances without burning through all their reserves.\u00a0\u00a0<\/p>\n

Our flexible metabolism \u2014 able to adapt to different diets and store fat for times when food is scarce \u2014 helped us survive and thrive. It also shaped how we age.\u00a0\u00a0<\/p>\n

Early in his career, Pontzer, who came to Duke\u00a0University\u00a0in 2017\u00a0as a scholar in residence and joined the evolutionary anthropology faculty\u00a0a year later,\u00a0measured daily energy expenditures in primates, a diverse group of mammals\u00a0such as\u00a0lemurs, tarsiers, monkeys,\u00a0apes,\u00a0and humans.\u00a0\u00a0<\/p>\n

His\u00a0subjects\u00a0ranged from\u00a0sedentary humans\u00a0to\u00a0zoo-dwelling chimpanzees, bonobos,\u00a0gorillas,\u00a0and\u00a0orangutans.\u00a0<\/p>\n

Like other primates, humans burn energy slowly compared to other mammals, a trait linked to longer lifespans. But within that slow-burn strategy, we stand out: our higher metabolism fuels big brains and frequent reproduction, key advantages in the evolutionary game.\u00a0\u00a0<\/p>\n

Pontzer explores these themes in his books \u201cBurn,\u201d and\u00a0\u201cAdaptable\u201d \u2014 the latter long-listed for a 2026 PEN America Literacy Science Writing Award, and in a buzzy\u00a02025\u00a0study showing that daily energy expenditure<\/a>\u00a0is strikingly\u00a0similar across\u00a0lifestyles, from hunter-gatherers to office workers.\u00a0\u00a0<\/p>\n

The takeaway from the study,\u00a0conducted with a\u00a0group of\u00a0international collaborators,\u00a0is that obesity in wealthy nations such as the U.S.\u00a0where\u00a02 out of 5 adults have obesity is driven less by inactivity and more by the easy access to calorie-dense, ultra-processed foods.\u00a0\u00a0<\/p>\n

For Pontzer,\u00a0science\u00a0isn\u2019t\u00a0just about weight\u00a0loss.\u00a0It\u2019s\u00a0about understanding what makes us human \u2014 and why our bodies work the way they do.\u00a0\u00a0<\/p>\n

\u201cWhen we don\u2019t have fluency in how our bodies work, it\u2019s hard to have meaningful conversations,\u201d he said. \u201cHow we understand our bodies is how we understand each other.\u201d\u00a0\u00a0<\/p>\n

Mary-Russell Roberson is a freelance writer living in Durham.\u00a0<\/p>\n

Eamon Queeney is the assistant director of multimedia and creative in the Office of Strategic Communications at the Duke University School of Medicine.\u00a0\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"Herman Pontzer, PhD, an evolutionary anthropologist at Duke University, investigates how the human body expends energy \u2014 and…\n","protected":false},"author":2,"featured_media":418777,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[37],"tags":[64,63,538,137],"class_list":{"0":"post-418776","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-fitness","8":"tag-au","9":"tag-australia","10":"tag-fitness","11":"tag-health"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/418776","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=418776"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/418776\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/418777"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=418776"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=418776"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=418776"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}