Investigators have found that just 4.5 minutes of vigorous activity per day could reduce the risk of some cancer types by up to 32%. The results of the recent study were published by Stamatakis et al in JAMA Oncology.
Background
Vigorous intermittent lifestyle physical activity describes very short bursts of activity—around 1 minute each—and includes activities such as doing vigorous housework, carrying heavy groceries around the supermarket, power walking, and playing high-energy games.
“[Vigorous intermittent lifestyle physical activities are] a bit like applying the principles of high-intensity interval training to your everyday life,” explained lead study author Emmanuel Stamatakis, PhD, MSc, Professor of Physical Activity, Lifestyle, and Population Health at the School of Health Sciences at the University of Sydney.
Individuals who don’t exercise may be at an increased risk of developing certain types of cancers like breast cancer, endometrial cancer, or colorectal cancer. However, until recently, the impact of less structured forms of vigorous physical activity was unable to be measured.
“We know the majority of middle-aged [individuals] don’t regularly exercise, which puts them at increased cancer risk, but it’s only through the advent of wearable technology like activity trackers that we are able to look at the impact of short bursts of incidental physical activity done as part of daily living,” highlighted Dr. Stamatakis. “It’s quite remarkable to see that upping the intensity of daily tasks for as little as 4 to 5 minutes [per] day, done in short bursts of around 1 minute each, is linked to an overall reduction in cancer risk by up to 18%, and up to 32% for cancer types linked to physical activity,” he emphasized.
Study Methods and Results
In the new observational study, the investigators used wearable device data to track the daily activity of over 22,398 individuals with a median age of 62 years who identified as non-exercisers. Vigorous intermittent lifestyle physical activity was assessed based on the participant’s activity levels as measured by wrist accelerometers worn over 7 days at the onset of the study.
They then followed the participants’ clinical health records for about 7 years to monitor for 13 cancer types associated with physical activity—including liver cancer, lung cancer, renal cell carcinoma, gastric cardia, endometrial cancer, myeloid leukemia, myeloma, colorectal cancer, head and neck cancer, bladder cancer, breast cancer, and esophageal adenocarcinoma.
The investigators discovered that the participants who performed as few as 4 to 5 minutes of vigorous intermittent lifestyle physical activity per day had a substantially lower risk of cancer compared with those who performed no vigorous intermittent lifestyle physical activity.
Additional results from the study included:
- 2,356 of the participants had been diagnosed with cancer during a follow-up period of 6.7 years—1,084 of which were physical activity–related.
- A minimum of about 3.5 minutes of daily vigorous intermittent lifestyle physical activity was associated with a reduced cancer incidence rate of up to 18% compared with 0 minutes of vigorous intermittent lifestyle physical activity.
- Vigorous intermittent lifestyle physical activity of 4.5 minutes per daily was associated with a reduced physical activity–related cancer incidence rate of up to 32%.
- The steepest gains in cancer risk reduction were seen in individuals who performed small amounts of vigorous intermittent lifestyle physical activity compared with those who did none; however, benefits continued with higher levels of daily vigorous physical activity, particularly for physical activity–related cancer types.
- Most vigorous intermittent lifestyle physical activity (92%) occurred in bouts of up to 1 minute.
Previous studies have demonstrated a strong link between intermittent vigorous physical activity and rapid improvements in cardiorespiratory fitness—which may provide a possible biological explanation for the reduced risk of cancer seen in the new study. The investigators noted that other likely contributors included the improved insulin sensitivity and chronic inflammation caused by vigorous physical activity.
Conclusions
“We need to further investigate this link through robust trials, but it appears that [vigorous intermittent lifestyle physical activity] may be a promising cost-free recommendation for lowering cancer risk in [individuals] who find structured exercise difficult or unappealing,” Dr. Stamatakis emphasized. “We are just starting to glimpse the potential of wearable technology to track physical activity and understand how unexplored aspects of our lives affect our long-term health. [T]he potential impact on cancer prevention and a host of other health outcomes is enormous,” he concluded.
Disclosure: For full disclosures of the study authors, visit jamanetwork.com.
