Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA.
Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02138, USA.
Curr Biol. 2021 Oct 25;31(20):R1375-R1376. doi: 10.1016/j.cub.2021.09.014.
Over the past two centuries profound technological and social changes have reduced overall levels of physical activity (PA). However, just how much population-level PA levels have declined since the Industrial Revolution is unknown because methods for measuring PA, such as accelerometry and the doubly labeled water technique, were developed only within the last few decades. Here, we show that historical records of resting body temperature (T) can serve as a 'thermometer' of population-level PA, enabling us to use the well-documented secular decline in T in the US to approximate PA decline in the US since 1820. Using cross-sectional data relating T to resting metabolic rate (RMR) and RMR to PA, we estimate that RMR has declined by ∼6% and moderate to vigorous PA by ∼27 minutes per day since 1820 in the US.
在过去的两个世纪里，深刻的技术和社会变革降低了总体体力活动（PA）水平。然而，由于仅在过去几十年中才开发出诸如加速度计和双标记水技术之类的 PA 测量方法，因此自工业革命以来人群水平的 PA 水平下降了多少尚不清楚。在这里，我们表明休息时体温（T）的历史记录可以作为人群水平 PA 的“温度计”，使我们能够利用美国有据可查的 T 的长期下降来估算自 1820 年以来美国的 PA 下降。使用 T 与静息代谢率（RMR）和 RMR 与 PA 的横断面数据，我们估计自 1820 年以来，美国的 RMR 下降了约 6％，中度至剧烈 PA 下降了约 27 分钟/天。
