Millions of women are not taking enough exercise because they are afraid of being ‘judged’, MPs warn.

They worry they will be ridiculed for being sweaty, out of breath or struggling at the back when jogging or at the gym.

Some women have taken to running in secret on treadmills installed in sheds in their back garden because they are too ashamed to do it in public.

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Millions of women across the UK are not taking enough exercise because they are afraid of being ‘judged’, a new report by MPs on the Commons’ Health Select Committee has found (file picture, posed by model)

A report by MPs on the Commons’ Health Select Committee also highlights how girls as young as ten shun PE classes because they worry about their body image.

Figures show that just over two thirds of women, 68 per cent, do not take the recommended level of exercise of two and a half hours over the course of a week.

This is much higher than the 56 per cent of men who do not do this weekly amount.

Experts have warned that a lack of exercise is as harmful as tobacco and contributes to up to one in six deaths in the UK.

Tory MP Dr Sarah Wollaston, chairman of the committee, said: ‘It is unacceptable that this gender gap has been ignored for so long. We need to be out there ensuring that girls can access the type of sport they want to take part in.’

Labour MP Barbara Keeley said girls aged ten, 11 and 12 were dropping out of games lessons because they were worried about showing ‘puppy fat’.

One woman interviewed by the committee was told by her male GP she was too fat to do the London Marathon even though she had run 18 miles the week previously.

Julie Creffield, a campaigner who encourages women to exercise, said she was determined to ‘prove him wrong’ and finished the event in 2013.

Mrs Creffield, 36, a mother who works as a motivational speaker, said many women were afraid to join running clubs or attend gym classes because they didn’t want to be the one ‘struggling at the back.’

This is particularly true if they are overweight or have gained a few pounds after having children.

She told the MPs: ‘I have women who tell me they run on a treadmill in their shed because they just don’t want to be seen in public, and that’s part of the problem. Because we don’t see many overweight women exercising in public, other women don’t think exercise is for them.’

The committee – which is also investigating obesity – spoke to an expert who accused hospitals that sell fast-food on their premises as being guilty of ‘negligence.’

Professor Theresa Marteau, of the Department of Public Health at Cambridge University, criticised Guy’s in London, where there is a McDonald’s and Addenbrooke’s in Cambridge, which houses a Burger King.

She said: ‘It is at best anomalous and at worst negligent that NHS properties continue to serve foods high in sugar, salt and fat.’