Low-moderate steady-state exercise elicits a neuroautonomic cardiovascular dysfunction in concussed athletes that is not present in a rested state. This dysfunction alludes to an exercise induced uncoupling between the autonomic and cardiovascular systems.

Objective: To determine if an athlete's capacity to perform exercise is impaired following concussion and whether this would be reflected by an altered heart rate response. Methods: Of the 14 concussed athletes, nine missed playing time as a direct result of their concussion and five did not. The concussed athletes performed an exercise protocol on a cycle ergometer within 72 hours of being asymptomatic at rest and a second test at 5 days following the previous assessment. Matched controls (n = 14) were tested using the same time line. The exercise protocol consisted of a 2 minute warm up, 10 minute, low2moderate intensity, steady state exercise session, and a high intensity interval protocol. The interval protocol consisted of a 40 second high intensity bout, followed by a 40 second rest period. This protocol continued until the participant had reached volitional fatigue. Results: The number of exercise bouts completed was not significantly different from their matched controls. However, concussed athletes who missed playing time had a significantly higher heart rate during the steady state exercise session. During this same period, they also exhibited a greater rise in heart rate over time. Conclusion: These findings indicate that exercise capacity is unaffected in concussed athletes who are asymptomatic at rest. However, their heart rate response to submaximal exercise is increased.

The objective of this study was to assess the changes in the physical capacity as a function of age in power line technicians (PLTs). The physical test was designed to closely represent the essential physical tasks of the occupation that were identified through a detailed job demand analysis. The results from the physical test showed that six out of nine test variables did not demonstrate a statistical difference between the mean scores of young (< or = 39 years) and old age (50+ years) groups. However the older group scored significantly lower in the aerobic capacity test, one-handed pull down, and both right and left standard handgrip tests. Despite these differences the older PLT appears to meet and exceed the physical requirements necessary to carry out the essential tasks of this trade. However a physical test with a high level of content and construct validity is necessary to accurately evaluate the workers physical capacity in relation to the job demands. Based on the principal of specificity for muscle training and testing, this study has demonstrated that heavy manual work appears to maintain physical capacity specific to the task as age progresses.

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It is traditionally believed that worker productivity declines with age. The greatest contributor to this stereotype, particularly in physically demanding jobs, is that older workers can no longer maintain their sustained level of work due to the age-associated decline in physical capacity. The objective of this study was to determine the change in the frequency of task performance as a function of age in the power line technician (PLT) trade. The task requirements of the PLT occupation were determined through the use of a detailed job demands analysis (JDA) and the frequency at which these tasks were performed was acquired through a survey derived from the JDA. The results of the survey were assessed as a function of age. Older lineworkers (> or = 50 years) were found to spend more time working on the ground whereas the younger PLTs (< or = 39 years) more frequently performed the climbing tasks and the corresponding work on the poles and towers. In contrast the older PLTs performed all pushing/pulling tasks at a greater or equal frequency to that of the younger lineworkers. Despite these differences the frequency of task performance is similar across the age groups studied.