Effects of physical training on physical performance in frail elderly people

Abstract

Aging is often accompanied by decreased muscle strength, aerobic capacity and balance, which can lead to impaired physical performance. Epidemiological data have demonstrated that low levels of physical activity are strongly related to functional decline. Frailty has been defined as a clinical syndrome comprised of unintentional body weight loss, self-reported exhaustion, muscle weakness, slow walking speed and a low level of physical activity in men and women over the age of 65. There is contradictory evidence regarding the effects of physical training on physical performance in frail elderly people.

The primary aim of this thesis is to describe the effects of physical training on physical performance i.e. muscle strength, aerobic capacity, balance, mobility and physical activity level as well as activities of daily living (ADL) and health-related quality of life (HRQL) in frail elderly people. Another aim is to investigate reliability with test re-test in one repetition maximum (1RM) in the arm/shoulder.

Ninety-six community-dwelling elderly people (58 women) were randomised to four different groups: i) physical training programme (aerobic, muscle strength, balance), ii) a nutritional intervention programme (individually targeted nutritional advice and group sessions), iii) a combination of these interventions and iv) a control group. At baseline the subjects were screened for physical performance as well as nutrition related variables. These measurements were repeated immediately after the intervention, which lasted for 12 weeks, and again six months later. During the last six months, the subjects in the training groups were encouraged to perform homebased exercises and to fill in training diaries. Two years after baseline, a third followup regarding ADL was conducted through telephone calls. The test re-test procedure with 1RM was conducted at one week-interval, comparing the reliability between test sessions, and also between subjects with or without previous muscle strength training experience.

A positive effect of the physical training programme was shown on leg muscle strength and habitual physical activity level for frail elderly people. Adding a nutritional intervention did not affect the results. There were no other significant differences between groups. Subjects with improvements in muscle strength, balance and mobility had significantly higher compliance compared to non-improvers. There were moderate significant correlations between compliance of the home-based exercises and improvements in personal ADL and HRQL.

There was a high correlation between the test sessions in 1RM, r=0.97 for both groups. An analysis of 95% limits of agreement for the mean difference was -4.3/+6.9 kg for the group without and -3.0/+6.4 kg for the group with previous muscle strength training experience, respectively.

In conclusion, the physical training programme showed a positive effect on leg muscle strength and habitual physical activity level. An individually tailored intervention is probably necessary to achieve a positive result on physical performance such as aerobic capacity, balance and mobility in frail elderly people. 1RM seems to be a reliable and safe method for dosing the intensity and evaluating a muscle strength training programme for elderly people.