Changes in physical capacity as a function of age in heavy manual work.

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.