38, 39, 40, 41 and 42

A sample of 35 Tarahumara (Table 1) were studied in the Sierra Tarahumara from the region around the Barranca de Urique and in the highlands between the Barrancas de Urique and Batopilas. Subjects were recruited by word of mouth with the help of a resident who is well known to many Tarahumara and with a local Tarahumara teacher who speaks Rarámuri (the native BGB324 price language of the Tarahumara). Unfortunately, it was difficult to recruit a large sample of individuals because most traditional Tarahumara live in isolated farms, far from roads and towns. In addition, the Tarahumara tend to be reserved and wary of outsiders, and many potential subjects, especially women, declined requests to be videoed while running. Of the 35 individuals studied, selleck chemical a combination kinematic and anthropometric data were collected from 23 individuals in December 2012. This sample includes 13 males (32.6 ± 12.9 years, mean ± SD) who wear only huaraches

(hereafter referred to as minimally shod Tarahumara), and 10 individuals (7 males, 3 females, 26.0 ± 11.9 years, mean ± SD) who wear western shoes (hereafter referred to as conventionally shod Tarahumara). Most of the conventionally shod individuals came from the town of the Urique. Anthropometric data were collected in December 2013 from an additional sample of 12 individuals (10 who were minimally shod and 2 who were conventionally shod). It was not possible to collect kinematic data from these individuals. None of the individuals measured had current lower

extremity injuries, but kinematic data from three individuals (all conventionally shod) were not analyzed for different reasons: one male ran in flip-flops; a second (1 female) was visibly distressed by the experiment, and ran in an awkward and evidently unnatural style; a third (1 female) was recorded with incorrect camera position. Accordingly, Table 2 presents data from 12 minimally shod and eight conventionally shod individuals. All individuals gave their informed consent in Spanish or Raramuri according to protocols approved by Harvard University. Basic background and anthropometric information was collected from all participants including age, sex, height, body mass, and leg length (measured from the greater trochanter to the base of the heel). Participants were asked to describe how far they travel every day, what kinds of physical activities they do on a regular basis, in what races they participate, and in what kind of footwear.