Mean PALs by age, sex, region, and season.

<p>Note: Daytime PARs based on factorial method from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0055679#pone.0055679.s003" target="_blank">Table S1</a> are averaged with PARs from evening and nighttime monitoring using the Accelerometer-HR method (PARn: Women  =  1.358, Men  =  1.422, 20–39 y  =  1.448, 40–59 y  =  1.336, 60+  =  1.330) (see text).</p

Linear regression model of BMI on 319 adults aged 20+.

°<p><i>p</i><0.1,</p>*<p><i>p</i><0.05,</p>**<p><i>p</i><0.01,</p>***<p><i>p</i><0.001.</p

Physical activity levels (PALs) for subsistence popuations.

<p>Note: Data sources include <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0055679#pone.0055679-Madimenos1" target="_blank">[12]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0055679#pone.0055679-Leonard2" target="_blank">[28]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0055679#pone.0055679-Pontzer1" target="_blank">[11]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0055679#pone.0055679-Kashiwazaki2" target="_blank">[67]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0055679#pone.0055679-Katzmarzyk1" target="_blank">[68]</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0055679#pone.0055679-Christensen1" target="_blank">[42]</a>. HG = hunter-gatherer, FH = forager-horticulturalist, PAST = pastoralist; DLW = doubly-labelled water method, Acc = accelerometry, HRM = heart rate monitor; AGPAST = agropastoralist, FARM = intensive agriculturalists;</p>1<p>also engaged in pig husbandry;</p>2<p>during low work season,</p>3<p>during high work season.</p

Predicted values of (a) PAR by age, sex, and region, and (b) BMI by age, sex, and Spanish fluency based on Model 2 in <b>Table 3</b> and <b>4</b>, respectively.

<p>All other variables held at baseline or population average.</p

Daily time (hrs/day) men and women spend in productive labor a) outside the household and b) domestic labor inside the household, based on time allocation sampling from 7am–7pm (see text).

<p>Daily time (hrs/day) men and women spend in productive labor a) outside the household and b) domestic labor inside the household, based on time allocation sampling from 7am–7pm (see text).</p

Physical Activity and Modernization among Bolivian Amerindians

<div><h3>Background</h3><p>Physical inactivity is a growing public health problem, and the fourth leading risk factor for global mortality. Conversely, indigenous populations living traditional lifestyles reportedly engage in vigorous daily activity that is protective against non-communicable diseases. Here we analyze physical activity patterns among the Tsimane, forager-horticulturalists of Amazonian Bolivia with minimal heart disease and diabetes. We assess age patterns of adult activity among men and women, test whether modernization affects activity levels, and examine whether nascent obesity is associated with reduced activity.</p> <h3>Methods and Findings</h3><p>A factorial method based on a large sample of behavioral observations was employed to estimate effects of age, sex, body mass index, and modernization variables on physical activity ratio (PAR), the ratio of total energy expenditure to basal metabolic rate. Accelerometry combined with heart rate monitoring was compared to the factorial method and used for nighttime sampling. Tsimane men and women display 24 hr physical activity level (PAL) of 2.02–2.15 and 1.73–1.85, respectively. Little time was spent “sedentary”, whereas most activity was light to moderate, rather than vigorous. Activity peaks by the late twenties in men, and declines thereafter, but remains constant among women after the early teens. Neither BMI, fat free mass or body fat percentage are associated with PAR. There was no negative effect of modernization on physical activity.</p> <h3>Conclusions</h3><p>Tsimane display relatively high PALs typical of other subsistence populations, but of moderate intensity, and not outside the range of developed populations. Despite rapidly increasing socioeconomic change, there is little evidence that total activity has yet been affected. Overweight and obesity are more prevalent among women than men, and Spanish fluency is associated with greater obesity in women. The lack of cardiovascular disease among Tsimane is unlikely caused by activity alone; further study of diet, food intake and infectious disease is needed.</p> </div

Linear mixed-effects models of PAR based on scan observations of adults age 20+ (n = 24,923 observations on 319 adults).

<p>Note: Random effects include person ID and time of day nested within person ID. Model 1 includes only main effects, Model 2 includes two-way interactions that improved AIC in a simultaneous inclusion procedure.</p>°<p><i>p</i><0.1,</p>*<p><i>p</i><0.05,</p>**<p><i>p</i><0.01,</p>***<p><i>p</i><0.001.</p

Mean physical activity ratio (PAR) by age and sex.

<p>Each data point represents one individual. PARs are derived from the factorial method, based only on observations from 7am–7pm (see text). The displayed curves are loess fits with 95% confidence intervals.</p

Hours per day by activity level, from accelerometry.

<p>Shown separately for men and women and for daytime (7am–7pm) and nighttime (7pm–7am) intervals. See text for definition of activity level categories.</p

Physical activity levels (PALs) from a compendium of populations, shown separately for developing (low or middle Human Development Index (HDI) populations) and developed societies (high HDI) [<b>40</b>].

<p>Tsimane are represented as the green triangle. Mean PAL for developing societies is 1.88 (men) and 1.70 (women), for developed societies is 1.79 (men) and 1.71 (women).</p