Can treadmill exercise capacity be predicted from arm ergometry results?

Arm exercise testing is used clinically in patients with leg disability. Few studies have reported normal arm performance values for middle-aged subjects, however, and physicians are more familiar with treadmill exercise. A total of 36 healthy men, aged 30 to 39 years (n = 10), 40 to 49 years (n = 10), 50 to 59 years (n = 9), or 60 to 69 years (n = 7) were evaluated using an incremental arm crank test and a Bruce treadmill test. Maximum oxygen consumption (V̇O(2max)) for treadmill and arm exercise declined with age at rates of 0.5 and 0.3 mL · kg^-1 · min^-1 · yr^-1, respectively, or 10% per decade. Arm exercise V̇O(2max) values (X ± SD) for the four advancing age groups (26 ± 8.3, 22 ± 5.4, 21 ± 2.7, 16 ± 2.8 mL · kg^-1 · min^-1, respectively) were 60% of the corresponding treadmill V̇O(2max) values. Maximum heart rate (HR) during arm exercise was 88% of that achieved with treadmill exercise for all age groups. Arm and treadmill V̇O(2max) were correlated (r = 0.81, P < 0.01), and arm and treadmill test duration were moderately related (r = 0.70, P < 0.05). The 95% confidence intervals for estimating individual treadmill time from the arm test encompassed two Bruce stages, however, prohibiting an accurate estimation of treadmill performance from the arm crank results. It was concluded that arm performance should be compared directly with existing norms for arm exercise and cannot be used to estimate individual treadmill capacity.