2016 年 5 巻 1 号 p. 7-12
Mechanical loads on the skeleton imposed by exercise increase bone mass and strength. The sensor in the osteocyte that detects mechanical stress, the mechano-sensor, responds to bone strain caused by mechanical loading. Greater magnitude and rate of strain increases osteogenic response, making high-impact exercise, which imposes large and dynamic strain on the skeleton, an effective mode of exercise. However, the sensitivity of the mechano-sensor (mechano-sensitivity) drops after a large number of repetitions performed within an exercise session, which has diminishing returns. It takes several hours or several days to reestablish mechano-sensitivity after the last loading session. It is important to consider the time to recovery of mechano-sensitivity when determining optimal exercise frequency.