Regulation of arm and leg movement during human locomotion.

Walking can be a very automated process, and it is likely that central pattern generators (CPGs) play a role in the coordination of the limbs. Recent evidence suggests that both the arms and legs are regulated by CPGs and that sensory feedback also regulates the CPG activity and assists in mediating interlimb coordination. Although the strength of coupling between the legs is stronger than that between the arms, arm and leg movements are similarly regulated by CPG activity and sensory feedback (e.g., reflex control) during locomotion

Physical activity after stroke and spinal cord injury

Conditions such as stroke and spinal cord injury (SCI) reduce the ability to activate muscle and produce movement, typically affecting a patient’s functional capacity and ability to carry out the tasks of daily living. Mobility limitations increase the risk of other avoidable chronic conditions such as cardiovascular disease, diabetes, cancer, osteoporosis, and depression, with dramatic negative effects on the overall quality of life. Appropriately prescribed exercise programs are needed to improve health status and overall quality of life for such individuals.1–3 Most authors now agree that moderate physical activity (PA) is well tolerated by such patients, and it seems to have few adverse side effects or contraindications when compared with common pharmacologic interventions.4 There are approximately 50 000 cerebrovascular accidents in Canada each year,5 and although stroke is only the third leading cause of death in North America, it is the leading cause of disability.6 There are more than 85 000 Canadians with SCI, and this number is projected to increase at a rate of approximately 3000 per year.7 Management of these conditions is thus a priority for today’s family physician. A large number of stroke and SCI survivors who could benefit greatly from a suitable program of PA are barred from participation because of incorrect perceptions about their functional capacity and undue concern about causing further harm. Commonly expressed concerns are exacerbation of spasticity and contractures, perceived inability to perform basic movements safely, and a substantial risk of falling. The notion that exercise (particularly resistance training) might exacerbate spasticity has now been refuted,8,9 and there is good evidence that individually tailored resistance or aerobic exercise programs can be performed safely after stroke or SCI.10–14 If such programs are not initiated, the reduced ability for movement and perceived barriers to exercise commonly lead to a progressive decrease in the individual’s overall PA, with all the adverse effects of concomitant physical deconditioning. This article provides an executive summary of findings from a systematic review of the risks of PA in stroke and SCI.15 It was undertaken as one in a comprehensive series of reviews examining the risks of PA in various chronic diseases. The evidence thus obtained provides the foundation for new tools to be used in exercise clearance: the revised Physical Activity Readiness Questionnaire (PAR-Q+) and the electronic Physical Activity Readiness Medical Examination (ePARmed-X+) procedure.16 We briefly discuss available data on the risks of PA in stroke and SCI, and present decision trees that facilitate the family physician’s task of setting appropriate PA prescription and guidelines for the ongoing monitoring of patients