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Sarcopenia, the loss of muscle mass with age, can start as early as one’s 30s, and affects a large proportion of the elderly. Fortunately, exercise can combat muscle aging, likely by reversing many of the age-related physiological changes at the root of this decline.
Muscle stem cells: Muscle stem cells, or satellite cells, decrease in number as we age. In elderly-human cells DNA methylation suppresses the expression of some genes, including sprouty 1, an important regulator of satellite cell self-renewal.
Mitochondria: Muscles develop abnormalities in mitochondrial morphology, number, and function with age.
Autophagy: Old muscles undergo lower levels of autophagy. Combined with lower protein production, this can result in an imbalance of proteins linked to muscle aging.
Blood-borne factors: Signaling factors known as myokines can be released into the blood directly or through excreted vesicles, and travel through the circulatory system to ...