For most of us, getting more exercise in our work day is beneficial. There’s no doubt about it – sitting behind a desk all day is bad for your body and international guidelines encourage people to engage in at least 30 minutes of moderate intensity exercise every day. Yet according to new research published in British Journal of Sports Medicine high levels of physical activity in work can actually be detrimental to your health.
Researchers in the Netherlands wanted to look at the difference in the effects of leisure time physical activity and occupational physical activity, claiming that a “physical activity paradox” meant on leisure time activity was good for you.
To do so, they looked at the results from 17 different studies that investigated the effects of job-related physical activity. Altogether, the different studies looked at more than 193,000 participants, with varying levels of physically demanding jobs. Occupational health research at VU Medical Centre in the Netherlands, Pieter Coenen, found that male workers with physically active jobs had an 18% higher risk of dying early compared to those less active occupations.
The researchers concluded that the high levels of occupational physical activity in manual workers elevates the heart rate and blood pressure for long periods of time, often over 40 hours per week, with an insufficient time for recovery. In contrast, leisure time physical activity typically takes place in a short, intense burst, accompanied by longer recovery periods.
Coenen added: “People who are very active at work spend eight hours a day being active. They may get very limited rest breaks; their heart rate and blood pressure are consistently high over the entire day. They may lead to the opposite of what is healthy for the heart, namely putting a strain on the cardiovascular system.”
Interestingly, no such association was observed among female workers, who in fact had a tendency for an inverse association, yet this could be down to the fact that women do not generally have occupations that require very heavy physical activity. The researchers also couldn’t conclude exactly why a more physically active job meant a higher risk of early death. It could be down to workers tending to be from lower socioeconomic groups, or having less education and lower incomes, tending to smoke more.
Yet the conclusion that can be drawn is that not all physical activity is beneficial to us – whilst your lunchtime run is great, for those with physically demanding jobs, getting the right amount of recovery time is important. Coenen said: “What I’m hoping for in general is that there is a better balance between work and leisure time physical activity.
“We could try to reduce the amount of physical activity at work, or try to add more breaks to reduce the overall intensity of physical activity on the job. One thing guidelines could also do is encourage workers to be more physically active during their leisure time.”