Waging war against physical-inactivity induced chronic diseases - revisited during the first decade of the 21st century

摘要

A decade ago, we proposed a plan to use exercise biology to wage war on the modern chronic diseases that emerged in the latter part of the 20th century [1]. The purpose of this review is to briefly recount whether the plan of performing research against physical inactivity had any success during the first decade of the 21st century. A series of three papers by Kump and Booth employed a rat wheel-lock model to determine the biological consequences of the cessation of voluntary running from cage activity. Rats were initially provided wheels to voluntarily run for 3 weeks, wheels locked after 3 weeks, and changes in skeletal muscle and adipose tissue were examined during the first 53 hrs of no wheel running. The concept was to drop from a higher to a lower physical activity level. This was done to mimic the biological consequences of going from a high level of native physical activity, such as our ancestors, to a lower activity level, mimicking today's reliance on non-labor devices. Our animal model differs from most present day humans in that wheel running is unstructured, intermittent physical activity, more reflective of our ancestor's activity patterns, as opposed to structured human exercise training models limiting activity within a small part of the day. In that sense, voluntary wheel running more closely approximates the patterns of young children playing over waking hours than humans working out.