Maximal fitness testing in sedentary elderly at substantial risk of disability: LIFE-P study experience.

BACKGROUND The authors sought to evaluate the acceptability and feasibility of maximal fitness testing in sedentary older individuals at risk for mobility disability. METHODS Maximal cycle-ergometer testing was performed at baseline and 6 and 12 months later in a subset of LIFE-P study participants at the Cooper Institute site. The mean age of the 20 participants (80% female) tested was 74.7 +/- 3.4 years. The following criteria were used to determine whether participants achieved maximal effort: respiratory-exchange ratio (RER) >1.1, heart rate within 10 beats/min of the maximal level predicted by age, and rating of perceived exertion (RPE) >17. RESULTS Participants' mean peak VO2 was 12.1 (3.7) mL . kg-1 . min-1. At baseline testing, only 20% of participants attained an RER >1.10, only 35% achieved a peak heart rate within 10 beats of their age-predicted maximum, and 18% had an RPE of >17. Subsequent testing at 6 and 12 months produced similar results. CONCLUSIONS In this pilot study of sedentary older persons at risk for mobility disability, very few participants were able to achieve maximal effort during graded cycle-ergometer testing.