Researchers have revealed that childhood cancer survivors leading sedentary lifestyles are at an increased risk of developing diabetes and heart disease.
Cancer treatments such as cranial radiation can damage the hypothalamus and pituitary; the result is an abnormal metabolism, which increases the risk of obesity and diabetes.
Moreover, chemotherapy with the drug anthracycline increases the risk of heart disease; and radiation to the body can cause blood vessels to become less pliant.
"Physical activity is a key step that survivors can take to reduce the health risk of these effects," said Dr Kiri Ness, of the Epidemiology and Cancer Control department at St. Jude.
During the study, the researchers analysed extensive data involving more than 20,000 childhood cancer survivors who received diagnoses between 1970 and 1986.
The researchers found that the cancer survivors showed significant deficits in physical activity compared to their siblings.
Survivors were less likely than their siblings to meet physical activity guidelines and more likely to report inactive lifestyles.
It was particularly striking that 23 percent of the survivors reported that they were completely inactive over the previous month, compared with 14 percent of their siblings," Ness said.
"For instance, if we know that patients with medulloblastoma who received cranial irradiation are at a high risk for having inactive lifestyles as adults, we might design a rehabilitation program they can undergo while they are still children to encourage physical activity as they age," the expert said.
Ness and her colleagues plan to investigate whether programs to encourage exercise in both children and adult childhood cancer survivors can help them avoid obesity, diabetes and other health problems.