The workforce is aging. In Canada, the next decade will see a 50 percent increase in workers aged 55-64 years. By 2015, it is estimated that 48 percent of the workforce will be in this age group. The median age in developed countries has reached a high of 37.4 years.
Although it is common for workers to move up in rank at the workplace as they gain age and experience to less physically demanding jobs, the great multitude of workers in this higher age group ensures that many will still be required to perform physically demanding tasks. Further, a number of occupations (i.e., paramedics, firemen, police officers, nurses and construction and manufacturing workers) require that, regardless of rank, the worker is able to perform physically challenging essential functions.
In their review article of aging and physical work capacity, Kenny et. al. identify research findings that include:
- The average physical work capacity of a 25 year old worker is double that of an average 65 year old worker
- As early as age 30, aerobic capacity begins to decline 5 to 15 percent per decade
- Maximal isometric strength is maintained to age 40 with a 5 percent loss seen by age 50; by age 60, a yearly loss of 1.0-1.5 percent occurs
- Concentric muscle strength diminishes at a rate of 8-10 percent per decade
- Muscle mass decreases, on average, approximately 30 percent by age 60, with a greater loss in the lower extremity
- The prevalence of musculoskeletal disorders among workers 51 to 62 years of age may increase as much as 15 percent, with higher reporting occurring within physically demanding jobs
Despite these overall declines, heavy physical labor can promote a task-specific fitness (i.e., arm muscle strength due to regularly grasping/moving heavy parts). But the best defense against age related physical capacity loss, according to the authors, is a structured exercise fitness program. The review disclosed studies that found fitness programs:
- Can prevent nearly all physical capacity losses among those aged 45 to 65
- Promote a lower prevalence of low back pain
- Are associated with less muscle tension, reduced heart rate, and lower perceived work stress among those who perform low physically demanding jobs
- Improve productivity and reduce absenteeism
The Bottom Line – How This Applies To Ergonomists
Due to a gradual lost of physical capability, many jobs may require older workers to perform close to their physical limits and create an increased risk of injury. This risk is heightened if work activities do not allow for an adequate duration of tissue recovery, according to studies cited in the review. When evaluating jobs, ergonomists should be sensitive to this growing, working-population age shift and its accompanying, potentially diminished physical capabilities. Besides applying worksite controls, it should be acknowledged that injury risk for this group can be reduced through structured physical fitness activities.
Other Key Article Points
The healthy worker effect (employees with lower physical capabilities retire or transfer to a less demanding job while workers in good physical condition continue with the job) commonly interferes with studies that look at the relationships between age and work.
- There is great individual variation as to rate of diminished physical capability due to genetics, lifestyle, and environmental influences.
Article Title: Physical Work Capacity in Older Adults: Implications for the Aging Worker
Publication: American Journal of Industrial Medicine, 51, 610-625, 2008
Authors: G P Kenny, J E Yardley, L Martineau, and O Jay
This article originally appeared in The Ergonomics Report™ on 2008-08-12.