Firefighters are more likely to be injured exercising than putting out fires, new research suggests.
A US study found exercising caused a third of all injuries, followed by carrying patients (17%).
Just over one in 10 (11%) injuries occurred during training drills.
Exercising is designed to help firefighters stay fit to deal with the rigours of their job.
The study, published online in the journal Injury Prevention, assessed workers at 21 fire stations serving Tucson, Arizona, between 2004 and 2009.
The 650 emergency workers included firefighters, paramedics, engineers, inspectors and chiefs.
Overall, 52% of injuries were among firefighters and paramedics, while 44% were among recruits, engineers and captains.
Firefighters had the most number of injuries overall but only one in 10 injuries occurred during firefighting.
The annual incidence of injury across the study was an average of 17.7 per 100 employees, most of whom were in their 30s and 40s.
Sprains and strains were the most common type of injury (67%), followed by cuts and bruising. Most (95%) of the injuries were minor in nature.
Almost half of time off work for injuries was caused by strains and sprains caused when firefighters carried patients.
The authors, from the University of Arizona and the Johns Hopkins Bloomberg School of Public Health in Maryland, concluded: ``While most studies related to the fire service have focused attention on the hazards and injuries during fireground operations, findings from the current study indicate that the largest percentage of injuries result from participation in some form of mandatory physical exercise during one's shift.
"These injuries occurred at twice the frequency of the next highest job task (ie patient transport).
"The purpose of physical exercise is to prepare one for their job and to condition a person to perform those job tasks with the utmost amount of efficiency, so that injuries are prevented.
"Therefore, it is somewhat of a paradox that physical exercise, which aims to prevent injuries (and other adverse health outcomes), is actually the most frequent cause of injury."
BY JANE KIRBY - Press Association Mediapoint