Functional muscle power testing in young, middle-aged, and community-dwelling nonfrail and prefrail older adults.

OBJECTIVE: To evaluate the stair climb (SC) and sit-to-stand (STS) transfer test for functional power assessment in young, middle-aged, and community-dwelling nonfrail and prefrail older adults. DESIGN: Cross-sectional study. SETTING: Sport science institute providing health-related exercise programs for older people. PARTICIPANTS: Participants (N=60; age, 22-81y) were divided into groups of young (n=15; 20-30y), middle-aged (n=16; 40-60y), nonfrail older (n=16; >65y), and prefrail older adults (n=13; >65y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: SC and STS transfer power were measured on 2 separate occasions. RESULTS: Age and height correlated positively (P<.001) with both power measures. Multiple linear regression analysis showed that 67.9% (R(2)) of the variance in SC power and 31.3% (R(2)) of the variance in STS transfer power can be attributed to age and height. Significant age-related subgroup differences were found for SC power (P=.001). Nonfrail and prefrail older adults differed significantly in both power measures (P<.001). CONCLUSIONS: The findings indicate that SC and STS transfer power are sensitive enough to distinguish between nonfrailty and prefrailty. This suggests that both tests are relevant clinical measures in older people.

Personalized Adaptive Control of Training Load in Cardio-Exergames--A Feasibility Study.

OBJECTIVE: This article presents a feasibility study of using an algorithm for an individual and adaptive control of training load in an ergometer-controlled exergame for aerobic training. An additional goal was to investigate the effects of the adaptive game on the players' motivation. MATERIALS AND METHODS: A two-phase approach (calibration and exercise phase) was applied in a sample of 16 physically active adults. In the cardio-exergame "LetterBird," the flight of a pigeon was controlled by the pedaling rate of a bike ergometer as input device. During the calibration phase the individual heart rate (HR) responses of the players were measured. In the exercise phase, these data were used to adjust the resistance of the ergometer using the proposed algorithm. The purpose of this algorithm was to induce an individually defined target HR and to keep it in a steady state. In order to establish a reference for further studies, the game experience was measured using the kids-Game Experience Questionnaire. RESULTS: In 15 of 16 participants the actual HR reached the intended individual HR range within 10 minutes after onset of exercise. However, the induced HR initially exceeded the target HR in 13 participants, which made load adjustments necessary. The analysis of the kids-Game Experience Questionnaire confirmed the motivational effect of the exergame "LetterBird." CONCLUSIONS: The results confirm that the proposed algorithm for personalized HR control in the game "LetterBird" is feasible. Furthermore, the cardio-exergame "LetterBird" seems to have a substantial short-term motivating effect.