Exercise paradox

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The exercise paradox, [1] also known as the workout paradox, [2] refers to the finding that physical activity, while essential for maintaining overall health, does not necessarily lead to significant weight loss or increased calorie expenditure. [3] This paradox challenges the common belief that more exercise equates to more calories burned and consequently, more weight loss. [4]

Contents

Hadza tribe case study

The exercise paradox emerged from studies comparing calorie expenditure between different populations. Fieldwork on the Hadza people, a hunter-gatherer tribe in Tanzania, revealed that despite their high levels of physical activity, the tribe burned a similar number of calories per day as sedentary individuals in industrialized societies. [5] [6] This finding, led by Duke University professor Herman Pontzer, contradicted the expectation that more active lifestyles would result in higher energy expenditures. [7]

In 2012, Pontzer and his team of researchers analyzed energy expenditure in 30 Hadza adults using the doubly labeled water method. Participants consumed water enriched with two distinct isotopes of hydrogen and oxygen. The team later assessed the concentration of these isotopes in urine samples, which correlates with the body's daily carbon dioxide production and, consequently, daily energy expenditure. [8]

Results indicated that Hadza women burned an average of 1,877 calories per day, which was nearly the same as the 1,864 calories burned daily by women in industrialized nations. Hadza men expended about 2,649 calories per day, which was within the standard error distribution for average calories burned by men per day in industrialized nations. [9]

The studies suggest that controlling caloric intake may be more necessary for managing weight than exercise alone. [10] [11]

Studies on other population groups

A 2011 meta-analysis of 98 studies found that individuals in low to middle-HDI countries (specifically, Bolivia, Cameroon, China, Gambia, Guatemala, India, Jamaica, Nigeria, Russia, South Africa, and Eswatini) showed no significant differences in energy expenditure compared to individuals in middle to high-HDI countries (specifically, the countries of Europe, United States, Canada, Mexico, Cuba, Chile, Brazil, Japan, Australia, and New Zealand), despite large differences in each country's obesity rate. [12]

See also

Related Research Articles

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<span class="mw-page-title-main">Obesity</span> Medical condition in which excess body fat harms health

Obesity is a medical condition, sometimes considered a disease, in which excess body fat has accumulated to such an extent that it can potentially have negative effects on health. People are classified as obese when their body mass index (BMI)—a person's weight divided by the square of the person's height—is over 30 kg/m2; the range 25–30 kg/m2 is defined as overweight. Some East Asian countries use lower values to calculate obesity. Obesity is a major cause of disability and is correlated with various diseases and conditions, particularly cardiovascular diseases, type 2 diabetes, obstructive sleep apnea, certain types of cancer, and osteoarthritis.

<span class="mw-page-title-main">Weight loss</span> Reduction of the total body mass

Weight loss, in the context of medicine, health, or physical fitness, refers to a reduction of the total body mass, by a mean loss of fluid, body fat, or lean mass. Weight loss can either occur unintentionally because of malnourishment or an underlying disease, or from a conscious effort to improve an actual or perceived overweight or obese state. "Unexplained" weight loss that is not caused by reduction in calorific intake or increase in exercise is called cachexia and may be a symptom of a serious medical condition.

Basal metabolic rate (BMR) is the rate of energy expenditure per unit time by endothermic animals at rest. It is reported in energy units per unit time ranging from watt (joule/second) to ml O2/min or joule per hour per kg body mass J/(h·kg). Proper measurement requires a strict set of criteria to be met. These criteria include being in a physically and psychologically undisturbed state and being in a thermally neutral environment while in the post-absorptive state (i.e., not actively digesting food). In bradymetabolic animals, such as fish and reptiles, the equivalent term standard metabolic rate (SMR) applies. It follows the same criteria as BMR, but requires the documentation of the temperature at which the metabolic rate was measured. This makes BMR a variant of standard metabolic rate measurement that excludes the temperature data, a practice that has led to problems in defining "standard" rates of metabolism for many mammals.

<span class="mw-page-title-main">Exercise intensity</span>

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<span class="mw-page-title-main">Weight gain</span> Increase in a persons total body mass

Weight gain is an increase in body weight. This can involve an increase in muscle mass, fat deposits, excess fluids such as water or other factors. Weight gain can be a symptom of a serious medical condition.

Resting metabolic rate (RMR) is whole-body mammal metabolism during a time period of strict and steady resting conditions that are defined by a combination of assumptions of physiological homeostasis and biological equilibrium. RMR differs from basal metabolic rate (BMR) because BMR measurements must meet total physiological equilibrium whereas RMR conditions of measurement can be altered and defined by the contextual limitations. Therefore, BMR is measured in the elusive "perfect" steady state, whereas RMR measurement is more accessible and thus, represents most, if not all measurements or estimates of daily energy expenditure.

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<span class="mw-page-title-main">Hadza people</span> Ethnic group

The Hadza, or Hadzabe, are a protected hunter-gatherer Tanzanian indigenous ethnic group, primarily based in Baray, an administrative ward within Karatu District in southwest Arusha Region. They live around the Lake Eyasi basin in the central Rift Valley and in the neighboring Serengeti Plateau. As descendants of Tanzania's aboriginal, pre-Bantu expansion hunter-gatherer population, they have probably occupied their current territory for thousands of years with relatively little modification to their basic way of life until the last century. They have no known close genetic relatives and their language is considered an isolate.

<span class="mw-page-title-main">Treadmill desk</span>

A treadmill desk, walking desk or treadmill workstation is a computer desk that is adapted so that the user walks on a treadmill while performing office tasks. Persons using a treadmill desk seek to change the sedentary lifestyle associated with being an office worker and to integrate gentle exercise into their working day.

Obesity in Mexico is a relatively recent phenomenon, having been widespread since the 1980s with the introduction of ultra-processed food into much of the Mexican food market. Prior to that, dietary issues were limited to under and malnutrition, which is still a problem in various parts of the country. Following trends already ongoing in other parts of the world, Mexicans have been foregoing the traditional Mexican diet high in whole grains, fruits, legumes and vegetables in favor of a diet with more animal products and ultra-processed foods. It has seen dietary energy intake and rates of overweight and obese people rise with seven out of ten at least overweight and a third clinically obese.

<span class="mw-page-title-main">Obesity in pets</span>

Obesity in pets occurs when excessive adipose tissue accumulates in the body, and is generally defined as occurring when an animal's body weight is at least 20% greater than its optimal body weight. Obesity is associated with metabolic and hormonal changes, and can predispose pets to illnesses like orthopedic disease, diabetes, and cancer.

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<span class="mw-page-title-main">Weight management</span> Techniques for maintaining body weight

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Herman Pontzer is an evolutionary anthropologist at Duke University, where he is associate professor of evolutionary anthropology and global health. He is best known for his research into human bioenergetics, specifically as it relates to energy expenditure and the exercise paradox.

Energy expenditure, often estimated as the total daily energy expenditure (TDEE), is the amount of energy burned by the human body.

References

  1. Pontzer, Herman (1 February 2017). "The Exercise Paradox". Scientific American. 316 (2): 26–31. Bibcode:2017SciAm.316b..26P. doi:10.1038/scientificamerican0217-26. PMID   28118335 . Retrieved 20 July 2024.
  2. Kurzgesagt – In a Nutshell (16 July 2024). We Need to Rethink Exercise – The Workout Paradox . Retrieved 20 July 2024 via YouTube.
  3. Burrell, Teal. "Why doing more exercise won't help you burn more calories". New Scientist. Retrieved 20 July 2024.
  4. "How exercising doesn't mean you burn calories". www.bbc.com. Retrieved 20 July 2024.
  5. Pontzer, Herman; Raichlen, David A.; Wood, Brian M.; Mabulla, Audax Z. P.; Racette, Susan B.; Marlowe, Frank W. (2012-07-25). "Hunter-Gatherer Energetics and Human Obesity". PLOS ONE. 7 (7): e40503. Bibcode:2012PLoSO...740503P. doi: 10.1371/journal.pone.0040503 . ISSN   1932-6203. PMC   3405064 . PMID   22848382.
  6. "Living Like a Caveman Won't Make You Thin. But it Might Make You Healthy | Duke Today". today.duke.edu. 17 January 2019. Retrieved 20 July 2024.
  7. "How Our Evolutionary Past Shapes Our Health Today". American Scientist. 23 February 2017. Retrieved 20 July 2024.
  8. "Comparing Calories: How the Hadza Tribe Informs our Understanding of Obesity". Ursa Sapiens. Retrieved 20 July 2024.
  9. Pontzer, Herman; Raichlen, David A.; Wood, Brian M.; Mabulla, Audax Z. P.; Racette, Susan B.; Marlowe, Frank W. (25 July 2012). "Hunter-Gatherer Energetics and Human Obesity". PLOS ONE. 7 (7): e40503. Bibcode:2012PLoSO...740503P. doi: 10.1371/journal.pone.0040503 . ISSN   1932-6203. PMC   3405064 . PMID   22848382.
  10. "Colloquy Podcast: Why Exercising More May Not Help You Lose Weight | The Harvard Kenneth C. Griffin Graduate School of Arts and Sciences". gsas.harvard.edu. Retrieved 2024-07-20.
  11. Zarracina, Javier (2016-04-28). "Why you shouldn't exercise to lose weight, explained with 60+ studies". Vox. Retrieved 2024-07-20.
  12. Dugas, Lara R; Harders, Regina; Merrill, Sarah; Ebersole, Kara; Shoham, David A; Rush, Elaine C; Assah, Felix K; Forrester, Terrence; Durazo-Arvizu, Ramon A; Luke, Amy (2011-02-01). "Energy expenditure in adults living in developing compared with industrialized countries: a meta-analysis of doubly labeled water studies". The American Journal of Clinical Nutrition. 93 (2): 427–441. doi:10.3945/ajcn.110.007278. ISSN   0002-9165. PMC   3021434 . PMID   21159791.