To evaluate the hemodynamic and metabolic requirements of activities of daily living (ADL), specifically simulated grocery carrying, 11 cardiac patients volunteered to perform three randomly assigned, 8 minute steady state treadmill trials at 53.6 m/minute.Methods
Trial 1 consisted of treadmill walking (No Load). Trial 2 required carrying a 4 kg load clutched to the chest by elbow flexion (Flex). Trial 3 required carrying 4 kg at the level of the thigh with the elbow extended (Extend). Open circuit spirometry was employed for the measurement of oxygen consumption. Blood pressure was obtained by auscultation.Results
There were no occurrences of angina, ST-T wave changes, or ectomy. Statistical analysis by ANOVA with repeated measures (P < 0.05) demonstrated that Trial 2 (Flex) elicited a systolic blood pressure significantly greater than Trials 1 (No Load) and 3 (Extend). Rate pressure product (RRP) and VO2 during Trials 2 (Flex) were significantly greater than Trial 1 (No Load).Conclusions
The greater reliance on the small elbow flexor group during the Flex trial may have stimulated a greater pressor response in addition to the elevated metabolic demand. To minimize metabolic and hemodynamic demands, cardiac patients should modify load carry to the extended elbow position while transporting groceries.