This study aimed to determine whether physical activity similar to daily living results in signs and sensations of fatigue in healthy old, balance-impaired old, and healthy young adults. Sensations of general tiredness, leg tiredness, knee-extension and hip-abduction strength, and temporospatial gait variables were measured before, immediately after, and up to 20 min after moderate-intensity physical activity. After activity, all groups reported increased levels of tiredness but showed no changes in strength. The balance-impaired had greater and more prolonged feelings of tiredness, with a mean increase before to immediately after activity of 3.6 on the visual analogue scale and no recovery at 16 min. The young and healthy old had an increase of 3 and 2.6, respectively, and had recovered before 16 min. In the balance-impaired group only, cadence slowed immediately after activity. It is proposed that these changes, in particular the prolonged feelings of tiredness, might limit daily activity.
The authors are with the School of Health and Rehabilitation Sciences, The University of Queensland, St. Lucia, QLD, 4072 Australia.