Regular exercise can help sufferers in the fight against cancer, according to new research.

Researchers believe that exercise equivalent to a 30-minute walk five times a week can help prevent cancer, slow the disease’s progress, enhance recovery and prevent its recurrence.   

Exercise cuts the levels of insulin, a hormone that causes most of the body's cells to take up glucose from the blood and triggers faster cell growth, boosting women’s risk of breast cancer and recurrence of the disease.

"This is one of the first studies out that has shown that in women who do not have a history of breast cancer, that they can actually reduce their risk by exercising," said Dr. Susan K. Boolbol, a breast surgeon at Beth Israel Medical Center.

Besides, exercise also cuts blood levels of estrogen and testosterone, two sex hormones produced in both men and women that have been associated with uterine lining, prostate and breast cancers. On top of that, exercise burns fat, which can hoard additional amounts of estrogen. Thus, by decreasing obesity, it diminishes the risk of a series of cancers.

Scientists also found that, when people sleep less than seven hours a night, the benefits of regular exercise may disappear. In some cases, the risk of developing cancer may actually double. "We think it's quite interesting and intriguing. It's kind of a first look into this. It isn't something that has been widely studied," said James McClain of the National Cancer Institute, part of the U.S. government's National Institutes of Health.

Another benefit of exercise is linked to cancer, many doctors recommending it to their patients, as a part of the therapy.