For the first time, researchers have documented that the same period of inactivity has a greater and more severe impact on the muscle power of the lower limbs of the old people than young people, which is essential for movements like climbing the stairs. The study findings were published in The Journal of Physiology.
Short periods of inactivity caused by hospitalization or not using the muscles because of a sedentary lifestyle can dramatically increase the decline in muscle mass, metabolic health and functional capacity. The loss of muscle power caused by disuse can be especially harmful to the elder people.
In the University of Udine in conjunction with the University of Padova, the researchers studied the impact of complete inactivity in a group of elderly people who were bedridden in a hospital environment for about 15 days. The study results were compared with young people.
The researchers found that in the old people there was a difference in single muscle fibre response to disuse, a more pronounced loss of muscle mass and a change in how muscle contraction is controlled by the nervous system compared with the young people.
Moreover, when compared to young people, the recovery phase was more difficult in the elder people. The study was conducted using healthy older people. However, the effects of inactivity and the difficulty recovering might be more pronounced in seniors who were suffering from diseases.
Carlo Reggiani, the lead investigator of that study said while clinical and epidemiological data on inactivity in the elderly are abundant, experiments on disuse and inactivity are seldom performed in elderly for several reasons.
The study results obtained are important to understand the inactivity-dependent enhancement of the decline in muscle mass, metabolic health and functional capacity as well as to design new rehabilitation protocols where timing and intensity of the sessions are optimized.
Further, the research team plan to follow-up the study by investigating the impairment of neural motor control on skeletal muscles, as an altered motor control was suggested when measuring the electrical activity of the muscles.
Several studies have shown that even modest physical activity could improve the health of old people. Giving just 15 minutes to exercise every day at the level of intensity of a brisk walk lowered the risk of mortality in older adults.