Predictors of Dropout in Exercise Trials in Older Adults: The Generation 100 Study.

PURPOSE: Dropout from exercise programs, both in the real world and in research, is a challenge, and more information on dropout predictors is needed for establishing strategies to increase the likelihood of maintaining participants in a prescribed exercise program. The aim of the present study was to determine the dropout rate and its predictors during a 3-yr exercise program in older adults. METHODS: In total, 1514 men and women (mean ± SD age = 72.4 ± 1.9 yr) were included in the present study. Participants were randomized to either a supervised exercise intervention or to follow national guidelines for physical activity (PA). Self-reported demographics (e.g., education), general health, morbidity (e.g., heart disease, memory loss, and psychological distress), smoking, and PA were examined at baseline. Cardiorespiratory fitness (CRF) and grip strength were directly measured at baseline. Dropout rate was evaluated after 1 and 3 yr. Multivariate logistic regression analysis was used to identify dropout predictors. RESULTS: The total dropout rate was 11.0% (n = 166) after 1 yr and 14.9% (n = 225) after 3 yr. Significant predictors of dropout after 1 yr were low education, low grip strength, lower cardiorespiratory fitness, low PA level, and randomization to supervised exercise. The same predictors of dropout were significant after 3 yr, with reduced memory status as an additional predictor. CONCLUSION: This is the largest study to identify dropout predictors in a long-term exercise program in older adults. Our findings provide new and important knowledge about potential risk factors of dropout in long-term exercise programs in older adults.

Exercise patterns in older adults instructed to follow moderate- or high-intensity exercise protocol - the generation 100 study.

BACKGROUND: Making older adults exercise and keeping them in exercise programs is a major challenge. Understanding how older adults prefer to exercise may help developing tailored exercise programs and increase sustained exercise participation in ageing populations. We aimed to describe exercise patterns, including frequency, intensity, type, location and social setting of exercise, in older adults instructed to follow continuous moderate-intensity training (MCT) or high-intensity interval training (HIIT) over a one-year period. METHODS: Frequency, intensity, type, location and social setting (alone vs. together with others) of exercise were assessed using exercise logs from 618 older adults (aged 70-77 years) randomized to MCT or HIIT. All participants completed exercise logs after each exercise session they performed during one year. Pearson Chi-square tests were run to assess the association between intensity, type, location and social setting of exercise with training group. RESULTS: Both groups performed 2.2 ± 1.3 exercise sessions per week during the year. Walking was the most common exercise type in both groups, but MCT had a higher proportion of walking sessions than HIIT (54.2% vs. 41.1%, p < 0.01). Compared to MCT, HIIT had a higher proportion of sessions with cycling (14.2% vs. 9.8%, p < 0.01), combined endurance and resistance training (10.3% vs. 7.5%, p < 0.01), jogging (6.5% vs. 3.2%, p < 0.01) and swimming (2.6% vs. 1.7%, p < 0.01). Outdoors was the most common exercise location in both training groups (67.8 and 59.1% of all sessions in MCT and HIIT, respectively). Compared to MCT, HIIT had a higher proportion of sessions at a gym (21.4% vs. 17.5%, p < 0.01) and sports facility (9.8% vs. 7.6%, p < 0.01). Both groups performed an equal amount of sessions alone and together with others, but women had a higher proportion of sessions together with others compared to men (56% vs. 44%, p < 0.01). CONCLUSION: This is the first study that has followed older adults instructed to perform MCT or HIIT over a one-year period, collected data from each exercise session they performed and provided important knowledge about their exercise patterns. This novel information may help researchers and clinicians to develop tailored exercise programs in an ageing population.

Cardiorespiratory Reference Data in Older Adults: The Generation 100 Study.

PURPOSE: Cardiorespiratory fitness (CRF) is regarded a clinical vital sign, and accurate reference values for all age groups are essential. Little data exist on CRF and cardiorespiratory function in older adults. The aim of this study was to provide normative values for CRF and cardiorespiratory function in older adults, including people with history of cardiovascular diseases (CVD). METHODS: In total, 1537 (769 women) participants age 70 to 77 yr underwent clinical examinations and cardiopulmonary exercise tests. Peak oxygen uptake (V˙O2peak), ventilation (V˙Epeak), expiration of carbon dioxide (VV˙CO2peak), breathing frequency (BFpeak), tidal volume (VTpeak), oxygen pulse (O2 pulsepeak), ventilatory efficiency (EqV˙O2peak and EqV˙CO2peak), and 1-min HR recovery were assessed. RESULTS: Men compared with women had higher V˙O2peak (31.3 ± 6.7 vs 26.2 ± 5.0 mL·min·kg), BFpeak (41.8 ± 8.0 vs 39.7 ± 7.1 breaths per minute), VTpeak (2.3 ± 0.5 vs 1.6 ± 0.3), O2 pulsepeak (16.4 ± 3.2 vs 11.3 ± 2.0), V˙CO2peak (2.9 ± 0.2 and 1.9 ± 0.1 L·min), V˙Epeak (96.2 ± 21.7 vs 61.1 ± 21.6 L·min), EqV˙O2peak (38.0 ± 6.9 vs 35.1 ± 5.6), and EqV˙CO2peak (33.5 ± 5.7 vs 31.9 ± 4.5). Women and men with CVD had lower V˙O2peak (14% and 19%), peak HR (5% and 6%), V˙Epeak (8% and 10%), VTpeak (7% and 4%), and lower EqV˙CO2peak (4% and 6%) compared with their healthy counterparts, respectively. Compared with healthy women and men, 1-min HR recovery was 12% and 16% lower for women and men with CVD. CONCLUSIONS: This study represents the largest reference material on directly measured CRF and cardiorespiratory function in older men and women, with and without CVD. This novel information will help researchers and clinicians to interpret data form cardiopulmonary testing in older adults.