Training and de-training effects: one year follow-up of a 3-month resistance exercise program in the pre-frail elderly

Background: Frailty is a fairly common biological syndrome in the elderly. Older adults (OAs) can be classified as in non-frail, pre-frail, and frail status. They may transition between levels of frailty according to their physical condition or after interventions. Purpose: The purpose of this study is to understand the training and detraining effects of a 3-month resistance exercise interventions in the pre-frail OAs. Methods: OAs from retirement communities and elderly congregation homes aged over 65 yearswere recruited.About 150 OAs were screened, among them, 107 pre-frail were invited, 78 agreed and 70 completed the program. After a consent form, each participant went through a series of comprehensive geriatric assessment, including basic data, health and lifestyle questionnaire, cognitive and depressive status, physical fitness tests (grip strength, knee extension strength, 30 sec sit-to-stand, arm-curl test, timed up and go, 5-meter walking time, 6minute walking distance, functional reach, one leg stand time, chair sit-and-reach, and reaction time) frailty level, quality of life (SF-36) and also monitoring of baseline activity level for 1 week by a pedometer. Then, they were randomly assigned into muscle resistance training and control groups. OAs in exercise groups participated 30min/session, 3 times/week exercise training for 3 months and were followed up at 6th m and 12th m. Generalized Estimation Equation (GEE) with 4 within (time) and 2 between (group) factors was applied for data analyses. Results: There were no significant differences of basic characteristic data between 2 groups. The results showed that compared with the control groups, resistance training group showed significant improvement in 30 sec sit-to-stand, arm-curl test, 5-meter walking speed and GDS scores at the conclusion of training. Some of the positive effects in the training group could maintain but some showed decline at the 6th month follow up (F/U), however, most revealed significantly decline at the 12thmonth F/U.The deteriorations of themotor function are evenmore obvious in the control group with some interaction effects. Besides, many older adults in resistance training group reported subjective feeling of wellbeing and getting fitter. Some also expressed the eager to continue the exercise program. Conclusion(s):A3-monthmuscle resistance training program has significant beneficial effects on upper and lower extremities muscle strength and endurance, gait speed and emotional status in the pre-frail OAs. However, there are detraining effects at the 6th months and almost returns to baseline at the 12th months. Compared with the training group, the control group revealed more significantly deteriorations especially at the 12th month F/U. Implications: A 3-month muscle resistance training program is feasible and effectiveness for the pre-frail OAs in improving both motor and emotional functions. However, there are de-training effects. Therefore, regular exercise is strongly recommended for the pre-frail OAs to maintain or even improve their functions.