According to a new analysis of more than 70 existing studies, the risk of cancer death for those diagnosed with cancer falls as physical activity rises.
The World Health Organization recommends a moderate physical activity to combat the risk of chronic disease. The WHO recommends two and a half hours of moderate exercise per week for some health benefit and five hours of moderate exercise per week for additional benefit. Half the time per week of vigorous physical activity can also have the same benefits.
The authors of the analysis note that there are no specific recommendations for physical activity levels to combat cancer risk, although more activity has been tied to lower risk of death from breast, colorectal and prostate cancers.
The results of the analysis may be able to help update the recommendation concerning the advisable amount of physical activity necessary to reduce cancer mortality.
The analysis included 71 studies of physical activity and cancer death risk in the general population or among a variety of cancer survivors.
After pooling the results, it was found that people in the general population who exercise for at least two and a half hours of moderate activity per week are 13% less likely to die from cancer than those with the lowest activity levels.
Researchers also looked at data in reference of MET hours. MET hour is a measure of relative amounts of energy expended in given activities and time spent doing them. Resting represents 1 MET, in contrast brisk walking represents 4 MET.
Cancer survivors who completed at least 15 MET hours per week of physical activity were 27% less likely to die from cancer.
At the moment, most studies have not been successful in addressing which type of physical activity is the most beneficial.
Authors of the study suggest that cancer patients should consult their doctors about a personalized physical activity plan which includes exercise time, exercise frequency, exercise mode etc… This personalized plan may help promote the survival or patients without bringing too much physical burden.