Exercise Unlocks Stem Cells in Muscles

The combination of aging and a sedentary lifestyle significantly contributes to the development of diseases such as osteoporosis, obesity, diabetes and cardiovascular diseases, as well as a decline in cognitive abilities. A common result of the aging process is sarcopenia, a decline in the mass and function of muscles. Dafna Benayahu, from Tel Aviv University (Israel), and colleagues studied a laboratory rat population, finding that endurance exercise increased the number of satellite cells (muscle stem cells), which normally decline with aging.  Comparing the performance of rats of different ages and sexes, they found that the number of satellite cells increased after rats ran on a treadmill for 20 minutes a day for a 13-week period. The younger rats showed a 20% to 35% increase in the average number of stem cells per muscle fiber retained -- and older rats benefited even more significantly, exhibiting a 33% to 47% increase in stem cells.  Further, the team found that endurance exercise improved the levels of "spontaneous locomotion,” a response mechanism that is typically reduced with aging.  The researchers are hopeful that this finding leads to discoveries of new methods to raise satellite cell populations in human muscle tissue, to raise the production and performance of young and healthy muscles, to provide an anti-aging musculoskeletal benefit.