Brigitte Holt is the recent recipient of NSF funding for her Tsimane Project which aims to link bone robusticity patterns with observed physical activity levels in a living population-a group of foragers/horticulturalists in Bolivia called the Tsimane. The study aims to measure activity profiles and limb bone structure (arm and leg bones) of children and adult Tsimane in order to document and understand better the relationship between bone structure and physical activity. Like many populations world-wide, the Tsimane are undergoing various levels of “modernization”, and are becoming more mechanized and sedentary. Because increased modernization and sedentism correlate with lower bone mass and increased incidence of fracture, Holt’s team also want to document differences in bone mass among Tsimane groups with varying degree of acculturation, and throughout the aging process.
The Tsimane have a very active life from early childhood. Boys and girls at an early age participate in tasks that require high levels of physical activity (gardening, fishing, hunting, fetching water and wood, carrying small children over long distances). Holt’s team hypothesize that this early active life reflects in strong arm and leg bones, and in maintenance of bone mass over the lifespan.
Data collecting started in November 2018, with a two-week trip to San Borja (Bolivia). Along with co-PI, Jonathan Stieglitz (University of Toulouse, France), Holt will collaborate with an established, NIH-funded project that includes a permanent medical and research clinic in San Borja. With the help of three Tsimane Research Assistants, Holt’s team collected physical activity and dietary information, as well as accelerometry data for Tsimane adult and children in two villages. Data collection is on-going in other villages, and will continue throughout the year. They are now in the process of purchasing a portable pQCT scanner that will be used to image arm and leg bone structure in Year 2 of the grant.