Walking briskly for just 20 minutes a day or enjoying a leisurely cycle ride could help stave off seven types of cancer, according to a new US study.

Research carried out by the American Cancer Society found that exercising moderately for around 150 minutes a week lowered the odds of being diagnosed with certain cancers.

The study, published in the Journal of Clinical Oncology, looked at the exercise habits of 755,549 people for a decade, examining whether meeting the recommended physical activity guidelines had an effect on cancer risk.

Partaking in two-and-a-half hours of exercise in a week reduced the risk of liver cancer by almost a fifth – 18 per cent – in both men and women. Five hours of moderate exercise a week reduced the risk by 27 per cent.

Statistics for breast cancer showed a 6 per cent reduction if women did 150 minutes a week, rising to ten per cent for those who did five hours of moderate exercise. Other cancers where the risk was lowered by exercise included kidney, myeloma, colon, womb cancer and non-Hodgkin’s lymphoma.

Doctors carrying out the research said the weight loss attributed to exercise was partially responsible for cutting the cancer risk, although those who were active but didn’t lose weight would still be afforded some protection compared to people who take no exercise.

Dr Alpa Patel, a co-author of the study from the American Cancer Society, said: “The exciting thing about these results is that they demonstrate engaging in a short amount of regular moderate-intensity activity, like a brisk walk, can provide tremendous benefits for the risk of getting various types of cancer.

“That is good news for the many people who, when they hear they should exercise more for their health or cancer prevention, think that means something drastic like having to start training for a marathon.”