Oxygen consumption and peak heart rate in stroke patients during the completion of the Modified Rivermead Mobility Index (MRMI)

Physical inactivity reduces cardiorespiratory fitness, which further compromises a stroke victim's daily living activities. It is well known that aerobic exercise can improve cardiorespiratory fitness. We conducted an exploratory study with an aim to compare oxygen consumption and peak heart rate between stroke patients and healthy participants during the performance of the tasks on the Modified Rivermead Mobility Index (MRMI) and to determine if these tasks reach an aerobic level of intensity during training. Oxygen consumption and heart rate were measured during the performance of the MRMI tasks in healthy patients and those who had suffered a stroke. Data between the two groups were compared using the independent t test and the Mann-Whitney U test, depending on if the criteria for parametric statistics were fulfilled. Results of the study found that there were no between-group differences in terms of the rate of oxygen consumption during the completion of the MRMI tasks (p > 0.05). Stroke patients took longer to perform the tasks (10-minute walk and stair climbing; p = 0.006) and, therefore, were associated with a higher total level of oxygen consumption compared with healthy participants (p < 0.001). The peak heart rate attained during all of MRMI tasks (except for rolling) by the stroke group was 50-60% of the age-predicted maximum heart rate, which was significantly higher than the healthy control group (p < 0.05) during the transfer and walking tasks. We concluded that stroke patients require more total oxygen to complete certain MRMI tasks. These functional tasks could potentially be used as adjunct protocols to assist patients with stroke during aerobic training, but this will require further study.