As many as one in three female runners can expect to experience breast pain when running and wearing a sports bra does not appear to help, new research suggests.

UK scientists questioned almost 1,300 women who took part in last year's London marathon. They were asked how often they exercised, how intense this exercise was, if they ever suffered pain in their breasts while exercising and if they wore sports bras or other supports while exercising.

One in three of the runners said they did experience breast pain. Women with larger breasts were more likely to report pain. In fact, half of those with a cup size of F or larger said they experienced pain while running.

Women who did not have any children were also more likely to report breast pain compared to women who had children.

Among those who reported pain, half said they experienced it during moderate exercise, while two in three said they experienced it during vigorous exercise.

Half of the women blamed the pain on their menstrual cycle, while one in eight said hormonal factors worsened the pain. One in seven said that exercise actually made the pain worse.

Almost one in 10 said the pain was excruciating or distressing, while one in six said it affected their ability to exercise.

At least one in four had reduced the intensity of exercise they took part in because of the pain.

Wearing a sports bra was seen as the most popular way of reducing breast pain during exercise, with nine in 10 of all runners stating that they wore one while running.

Since pain was still an issue for many of these women, the researchers suggested that ‘sports bra design and manufacture needs improvement'.

While around one in eight of those who experienced pain admitted to taking painkillers or holding their breasts when they ran, almost half simply put up with the pain.

"The link between exercise and breast pain has yet to be established. However, this study identified that exercise was the most prevalent factor in mastalgia (breast pain) occurrence, which may have implications for its management," the scientists said.

Details of these findings are published in the British Journal of Sports Medicine.