Males and females at the lower end of the physical capability spectrum should be trained more gradually

Lt Col Ian Gemmell

Until recently, although female army recruits were trained alongside the men, they were not expected to reach the same level of physical fitness.

This 'gender fair' policy was rejected when it was found that many women subsequently lacked sufficient strength for the work they were expected to do on completion of their training.

Since 1998, soldiers have been selected on a 'gender free' principle, where the same physical tests are applied to male and female army applicants, both sexes undergo identical training, and the women are expected to reach the same fitness levels as the men.

Lt Col Gemmell looked at medical discharges among recruits trained under the old policy (1997-98), and compared them with the data for 'gender free' recruits (1998-99).

For the men, the proportion of medical discharges due to overuse injury - for example, stress fractures, tendonitis and back pain - remained below 1.5%.

But for women, it rose from 4.6% to 11.1% under the new training regime.

Overuse injury

This means that women are now eight times more likely than the male recruits to be discharged with an overuse injury.

Lt Col Gemmell suggests several possible reasons for the rise, including:

• differences in women's bone size and muscle mass mean training causes 33-39% more stress on the female skeleton than the male
• in a mixed platoon of recruits, the women tend to march at the men's longer stride, putting their bones and muscles under even more stress
• research suggests that women's muscles can 'mimic' male muscle, but over a longer training period: 6 months rather than the standard 12 weeks

Lt Col Gemmell called for a review of selection tests and training methods in the light of his findings.

He told BBC Radio 4's Today programme that the overuse injuries that female recruits were suffering were similar to those suffered by women athletes.

Lt Col Ian Gemmell: men's and women's bodies are different

"Among army recruits in general that means lower limb injuries such as ankle strains, knee pain and stress fractures.

"Males and females at the lower end of the physical capability spectrum should be trained more gradually and perhaps over a longer period of time."

But he admitted there were budgetary constraints affecting Army policy.

A spokeswoman for the Army said women played a crucial role in the service, which could not operate as efficiently without them.

No infantry

Women are considered for 70% of the roles in the Army, and the position is currently under review.

They are not currently considered for the infantry or Royal Armoured Corps due to a lack of strength and stamina.

A Ministry of Defence spokesman said: "Findings of these papers were notified to the initial training group and modifications were made to the selection process with the introduction of a 1.5 mile run at recruitment selection centres as a risk reducer.

"This also includes a revised physical training (PT) syllabus. Further research projects have been commissioned to look at risk factors and the initial training group will consider further changes that may be needed."

The research is published in the Journal of the Royal Society of Medicine.