Aerobic reserve and physical functional performance in older adults.

BACKGROUND

older adults can be limited in their performance of daily tasks due to an inadequate aerobic capacity. Aerobic capacity below minimum physiological thresholds required to maintain independence leaves older adults with little, or no, aerobic reserve.

OBJECTIVE

the aim of this study was to measure functional performance and aerobic reserve in older adults during the serial performance of daily tasks.

SUBJECTS

twenty-nine (n = 29) men and women (n = 23 females) 70-92 years of age participated in this study.

METHODS

performance based physical function was assessed using the Continuous-Scale Physical Functional Performance test (CS-PFP). A Cosmed K4b(2) portable metabolic system was used to measure VO(2PEAK) and oxygen uptake during the serial performance of a battery of daily tasks (VO(2PFP)). Aerobic reserve was calculated as the difference between VO(2PEAK) and VO(2PFP).

RESULTS

the correlation coefficient between aerobic reserve and functional performance was r = 0.50(P = 0.006). Participants utilized 32.2 +/- 8.1%, 42.7 +/- 10.8%, and 50.3 +/- 12.3% of VO(2PEAK) for the low, moderate, and high workloads of the CS-PFP, respectively.

CONCLUSIONS

light housework and carrying groceries require 40 to 50% of peak oxygen consumption. This information can be used by clinicians and health professionals working with older adults as a guide to how much aerobic fitness is needed to perform ADLs and maintain independence. These can then be used as guides for assessment and for setting training goals in older adults.