Part-time soldiers or reservists need better training and support, a committee of MPs has warned.
The Public Accounts Committee report said reservists were now being used at “unprecedented levels”.
But it warned that the Reserve Forces were under-staffed, and some were not passing basic fitness tests.
Among the report’s suggestions was cut-price gym membership to allow volunteers to reach “the necessary levels of fitness”.
More than 12,000 reservists have served in Iraq since 2003 – and five have died on operations.
The committee’s chairman, Tory MP Edward Leigh, said: “The Ministry of Defence cannot have it both ways. You cannot treat reservists as second-class members of the Armed Forces while demanding a first-class job from them.”
Armed Forces minister Bob Ainsworth said he welcomed the report.
“Since the committee last heard evidence a year ago, many of the report’s areas of concern have been addressed – particularly provisions for the welfare, training, recruitment and equipping of the Reserves,” he said.
“We set rigorous standards for physical fitness which every reservist deploying on operations is tested against prior to deployment, and the report acknowledges this.”