Female soldiers (file picture) are expected to be granted access to front line units later this year prompting a review of fitness requirements

The Army is re-writing its fitness tests to make sure women can qualify for front line units once rules are changed this year, it was reported today.

Physical differences between men and women will be recognised in the tests as Defence Secretary Michael Fallon prepares to sign off on plans to allow women into the most dangerous roles for the first time.

Female soldiers are expected to be allowed to join close combat units, including the infantry and armoured regiments, for the first time from this summer.

The reforms will come alongside changes to the Army's physical training which is currently 'optimised for male physiology', the Sunday Times reported.

The new standards will be introduced from 2019 and are intended to better balance the demands of a specific military role with the training given to the individual recruit.

Research which has driven Mr Fallon's expected decision found women were twice as likely to suffer musculoskeletal injuries during initial training.

And analysis of recent Army recruits suggests only 30 women a year would pass the current physical standards for joining the front line units.

The study found: 'We know that women are built differently to men — higher fat mass, less muscle mass, less cardio output, which leads to greater/quicker energy deficit than men and they have to work harder to achieve the same output.'

Sources told the Sunday Times the modified tests will not be aimed to 'satisfy a gender requirement' but will be an attempt to 'drive down' the number of women injured.

One test being reviewed is a requirement for women under 30 to be able to do 21 press-ups, 50 sit-ups and run one and a half miles in 13 minutes or less. Also under review is the requirement for infantry to complete an eight-mile march carrying a 55lb rucksack within two hours.

Colonel Richard Kemp, who commanded British forces in Afghanistan, warned: 'You will have infantry soldiers who are less capable than they are today.

'I have spoken to people who are serving in the infantry who said that if women are allowed in, they will leave.'

General Sir Nick Carter, chief of the general staff, said: 'I want to make it very clear that there will be no lowering of training or qualifying levels for soldiers in ground close combat roles.'

A Ministry of Defence spokesman said: 'The MOD is undertaking a review to establish the physical standards required for ground close combat, which is due to complete in 2019.

'It will be based upon the principle that any standards will be related to the required role rather than individual characteristics.

'No decisions have been taken and any claims of what this will involve are pure speculation.'