Hunter-gatherers, exercise and heart disease
Staffan Lindeberg (staffan.lindeberg@dalby.lu.se)
Sun, 29 Dec 1996 01:20:29 +0100
Maureen & Dale Smith wrote:
> [Aboriginal hunting groups] also exercise more than the average bear. I've seen
> them and the hunting aboriginies are on the go alot more than a normal person
This was true for Australian Aborigines [1] but not quite for
hunter-gatherers of most other parts of the world. On an average they
have spent 2-3 hours per day for subsistence activities.
A fairly low level of physical activity has been the rule among many
traditional populations, particularly hunter-gatherers and tribal
horticulturalists, who have spent an average of three hours or less each
day on food production [2-6]. On the one extreme, a female Machiguenga
of the Amazon dug up enough tubers in one hour to feed 25 adults for one
day [6]. On the other extreme we find populations living in deserts, the
Arctic or similar marginal habitats and who have spent more than seven
hours a day hunting or gathering [2]. The very high level of physical
exercise exerted by the Tarahumara Mayans of Mexico [7] can hardly be
considered representative for traditional human populations.
> ...the point is that exercise also lowers bad cholesterol...
Physical activity undoubtedly exerts a number of potentially beneficial
effects on cardiovascular risk factors, including reduction of blood
pressure, body weight and waist to hip ratio, and elevation of HDL
(good) cholesterol [8]. Higher levels of physical activity are
furthermore prospectively associated with lower mortality [9-10].
Besides its possible genuine effects, exercise may facilitate an
adequate intake of essential nutrients by way of increased energy
expenditure [11]. Nevertheless, available evidence do not suggest that
exercise is as efficient as dietary changes to lower body weight [8, 12]
or blood pressure [13], nor do cross-cultural surveys indicate that a
high level of physical activity is a necessary condition for very low
rates of coronary heart disease.
Staffan Lindeberg MD PhD
1. O'Dea K. Marked improvement in carbohydrate and lipid metabolism in
diabetic Australian aborigines after temporary reversion to traditional
lifestyle. Diabetes 1984; 33:596-603.
2. Hayden B. Subsistence and ecological adaptations of modern
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gathering and hunting in human evolution. New York: Columbia University
Press, 1981: 344-421.
3. Sahlins M. Stone Age Economics.Chicago: Aldine, 1972
4. Taylor CB, Ho KJ. Studies on the Masai. Am J Clin Nutr 1971;
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5. Lee RB. What hunters do for a living, or, how to make out on scarce
resources. In: Lee RB, DeVore I, ed. Man the hunter. Chicago: Aldine,
1968: 30-48.
6. Johnson A, Behrens CA. Nutritional criterioa in Machiguenga food
production decisions: a linear-programming analysis. Human Ecology 1982;
10:167-89.
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runners--the modern Spartans. Am Heart J 1971; 81:304-14.
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Am Heart J 1991; 122:1723-39.
9. Shaper AG, Wannamethee G, Weatherall R. Physical activity and
ischaemic heart disease in middle-aged British men [published erratum
appears in Br Heart J 1992 Feb;67(2):209]. Br Heart J 1991; 66:384-94.
10. Sandvik L, Erikssen J, Thaulow E, Erikssen G, Mundal R, Rodahl K.
Physical fitness as a predictor of mortality among healthy, middle-aged
Norwegian men [see comments]. N Engl J Med 1993; 328:533-7.
11. strand PO. Physical activity and fitness. Am J Clin Nutr 1992; ?.
12. Singh RB, Singh NK, Rastogi SS, Mani UV, Niaz MA. Effects of diet
and lifestyle changes on atherosclerotic risk factors after 24 weeks on
the Indian Diet Heart Study. Am J Cardiol 1993; 71:1283-8.
13. Arroll B, Beaglehole R. Does physical activity lower blood pressure:
a critical review of the clinical trials. J Clin Epidemiol 1992;
45:439-47.
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