A new study has claimed that jobs requiring high levels of physical activity can increase the risk of early death in men.

Researchers at the Vrije Universiteit University Medical Center in the Netherlands have conducted a study to analyze previous research suggesting that high physical activity at work increases the chances of premature death.

The findings, published in the British Journal of Sports Medicine, show that men who are working physically strenuous jobs are 18 percent more likely to die prematurely compared to workers who are physically inactive. Most of those who are at risk tend to be "blue collar" workers, according to the researchers.

The study suggests that the effects of physical activity during leisure time is different from work-related physical activity.

"[W]hile beneficial health outcomes have been associated with high level leisure time [physical activity], detrimental health consequences have been documented for high level occupational [physical activity], regarding cardiovascular disorders, sickness absence, and mortality," the researchers noted, according to Medical News Today.

The latest research involved an analysis of 17 studies - amounting to data on 193,696 individuals - that considered the connection between work-related physical activity and the risk of mortality.

The researchers noted that the link between strenuous physical activity at work and the increased risk of premature death was still present even when accounting for exercise during leisure time.

The same link, however, was not found in the case of women. The study reportedly showed an "inverse association" between high physical activity at work and risk of premature death when applied to female workers, but the researchers noted that the association was "non-significant."

Pieter Coenen, public health researcher at VU University medical centre, suggested that the "physical activity paradox" may be due to the difference in the type of exercise done during leisure time compared to the activities at work.

He further noted that those who exercise during leisure time are allowed to rest at anytime, whereas those at work are not always allowed take breaks when they want to.

"If you go out for a run for half an hour in your leisure time, that increases your heart rate and you feel well afterwards, but when you are physically active at work, it's a very different type of activity," Coenen said, according to The Guardian. "You are working for eight hours a day and have limited rest periods. You are lifting, doing repetitive movements, and manual handling".

He surmised that the type of activity at work can strain the cardiovascular system rather than improve a person's fitness.

The authors stressed that the study does not establish a causal relationship between high physical activity at work and increased risk of premature deaths as they only considered the associations.