Muscle decline and physical training in the elderly
The BETTER-AGING project researched the causes of frailty and evaluated the benefits of a training programme for the very old. The project evaluated neuromuscular function in older individuals, since one of the characteristics of ageing is a decrease in muscle mass and strength. The decline in neuromuscular function and performance with ageing can be estimated by the measure of the maximal voluntary contraction torque (MVC). However, this impairment of strength is muscle group dependent. The project investigated the effects of a six-month strength-training programme on the major muscle groups around the ankle. Although a training programme in old age is highly effective in recovering strength, it does not appear to improve the reflex activity of the muscles. These were found to decline in older adults, suggesting that this change could be linked to degenerative phenomena. The plasticity of muscle elastic properties in older individuals was also evaluated following a strength-training programme. The first study determined stiffness during planar flexion in young and older people. This was similar between the age groups, suggesting an adaptive mechanism. The second study examined differences between older women and older men. Greater stiffness in women may be due to disparities in the muscle tissue, explaining in part their greater frequency of falling. The third study investigated the degree of recovery of motor function following a six-month strength-training programme. The reduced stiffness may be due to structural and neural adaptations, counterbalancing some of the effects of the neuromuscular ageing. Research of this nature into the possible reversal of the effects of ageing can only improve quality of life for the elderly. Musculo-skeletal frailty is the main factor affecting independent living until death. Social exclusion can therefore be avoided by maintaining mobility, postural stability, the ability for self-care and preventing falls.