RELATIONSHIP BETWEEN PHYSICAL STRAIN DURING STANDARDIZED ADL TASKS AND PHYSICAL CAPACITY IN MEN WITH SPINAL-CORD INJURIES

To describe physical strain during activities of daily living (ADL), 4 4 men with spinal cord injuries (C4-L5) performed a set of standardise d tasks. The physical strain was defined as the highest heart rate res ponse expressed as a percentage of the individual heart rate reserve ( %HRR). The physical strain averaged over the subjects who performed al l tasks (n = 24) was (mean +/- SD): 20.2 +/- 7.2 %HRR (washing hands), 20.4 +/- 7.3 %HRR (passing a side-hung door), 28.8 +/- 10.8 %HRR (tra nsfer to a toilet), 31.2 +/- 13.1 %HRR (ascending an 8 cm curb), 33.9 +/- 12.0 %HRR (transfer to a shower seat), 35.1 +/- 10.5 %HRR (transfe r to bed), 36.4 +/- 13.3 %HRR (preparing lunch) 37.1 +/- 12.0 %HRR (wa shing up), 38.7 +/- 14.9 %HRR (ascending a ramp), 39.8 +/- 15.6 %HRR ( transfer to a shower wheelchair), 41.4 +/- 12.1 %HRR (changing sheets) , and 45.9 +/- 10.4 %HRR (entering a car). Physical strain could be no tably high, but large variations among subjects were present. During a ll tasks, subjects with tetraplegia had significantly higher levels of strain than subjects with low (T6-L5) lesions. Physical strain was in versely related to parameters of physical capacity: isometric strength (r: -0.34 to -0.72), sprint power (r: -0.34 to -0.69), peak oxygen up take (r: -0.41 to -0.81) and maximal power output (r: -0.52 to -0.82). Parameters of physical capacity were better predictors of physical st rain than was the lesion level, and explained 37-71% of the variance i n strain during ADL. It was also concluded that the method used in thi s study provides a quantitative and objective estimation of physical s train and may therefore be a useful tool to identify task difficulty d uring rehabilitation and to evaluate the results of task and physical training on the physical strain during ADL.