A few minutes of "everyday" activity reduces cancer risk
An analysis of fitness tracker data has shown that a few short periods of activity throughout the day reduce the risk of developing cancer.A team of researchers led by the University of Sydney has shown that as little as 4.5 minutes of activity during the day while performing everyday tasks reduces the risk of developing some cancers by a third. The researchers cite active housework, carrying heavy shopping from the store, going for a brisk walk or playing vigorously with children as examples of possible "exercises".
To conduct the study, scientists used data from wearable devices (fitness trackers, smart watches and other similar devices) stored in the UK Biobank database. The scientists drew a sample of over 22,000 people who reported that they did not exercise regularly and rarely went for long walks. They used seven years of physical activity tracking data and medical records for the analysis.
The researchers analyzed "energetic intermittent physical activity" - short bursts of activity, each lasting about a minute. The risk of certain cancers is known to be reduced in people who exercise regularly. These include breast cancer, esophageal cancer, colorectal cancer and gastric cardia, for example.
The study found that study participants who recorded 4-5 short periods of intense "exercise" were less likely to develop cancer. Overall, the risk was 18% lower in this group, and 32% lower for the 13 cancers associated with physical activity.
Although the study is observational in nature and does not reveal a cause-and-effect relationship, the researchers are convinced that such a significant difference cannot be coincidental. They speculate that intermittent physical activity leads to improved cardiorespiratory endurance, which may provide a possible biological explanation for the reduced cancer risk.
Other possible factors include the effect of physical activity on improving insulin sensitivity and chronic inflammation. Future studies will help to identify and characterize the specific biological and chemical processes involved in these changes.