The role of effort in the recovery of arm function following a stroke

Stroke patients often report an increased sense of effort when using their paretic limb. Currently there is little research investigating this phenomenon and the implications that it could have for recovery. This study was an exploratory piece of work which combined quantitative and qualitative methods to investigate the role of effort in the recovery of arm function following a stroke. For the study, a new piece of equipment was designed called the assessment of perceived stiffness to provide a measure of effort that was less open to subjective bias than previous studies. In this new approach, stroke patients were asked to subjectively match the force of the grip strength being exerted by the impaired and unimpaired hand and then measures of the actual force being applied were taken using a dynamometer that was attached to the equipment. An interview schedule was also designed to examine stroke participants' experiences of effort and compare them with the performance on the assessment of perceived stiffness. Seventeen participants were recruited for the study and were divided into three groups namely, a stroke participant group, an age-matched control group and a young control group. The stroke participants? performance on the assessment of perceived stiffness was compared with that of the two control groups. The stroke participants? perception of perceived stiffness was then compared with their reports of increased effort in everyday life when they performed a movement task with their recovering arm. Furthermore, the research investigated whether stroke participants make a distinction between physical effort and mental effort. The results from the stroke sample showed that there were differences in their perception of stiffness compared to the control groups. The stroke participants? performance suggests that they were perceiving a greater stiffness on their paretic side when exhibiting the same amount of force on both sides. The results from the interview data demonstrated that the stroke participants who perceive increased stiffness on their paretic side report greater effort in everyday life. Individual differences were demonstrated when stroke participants were asked if they made a distinction between physical effort and mental effort. The results confirm the findings of previous studies and add weight to earlier research that an increased sense of effort is reported during recovery of arm function. Furthermore, this study highlights the need for additional research to investigate this area. The clinical implications of the results and areas for future research are discussed in detail.