Fitness trackers may help cancer survivors
Physical activity predicts better prognosis following cancer diagnosis. However, cancer patients typically decrease their levels of physical activity after diagnosis. Would wearable physical activity monitors lead cancer patients to increase their physical activity? Researches in Australia conducted a systematic review and meta-analysis of 35 controlled intervention trials that involved wearable devices (and sometimes other factors such as baseline counseling). Trials lasted from four weeks to one year. Compared to controls, interventions with wearable trackers led to significant increases in weekly combined moderate- and vigorous-intensity physical activity, moderate-intensity physical activity, total activity, and daily steps with moderate to large effect sizes. In addition, interventions with wearable trackers also led to significant increases in quality of life, aerobic fitness, and physical function, plus lower fatigue, with small to moderate effect sizes. The interventions appeared to be acceptable to participants and had low levels of adverse events. One note of caution: The quality of the included studies ranged from low to very low. Wearable physical activity trackers could help cancer patients increase their levels of physical activity and live better.
More physical activity may reduce your cancer risk
Studies that investigate the decline in mortality risk with increasing numbers of daily steps show positive yet inconsistent results. Is there a minimum number of daily steps needed to realize health benefits? Is there an upper limit of daily steps above which the health benefit ceases? Is the widely promoted ‘10,000 daily steps’ valid? Does step intensity matter? A team of researchers used data for 78,500 participants with an average age of 61 years in the UK Biobank Study to help clarify matters. Physical activity data came from wrist-worn accelerometers over a week’s time.
Over a median follow-up of seven years, results did not reveal a lower limit that must be exceeded or an upper limit above which daily steps predicted no further reduction in mortality or cancer risk. The risk of all-cause mortality and cancer (a composite of 13 types of cancer) tended to decline steeply up to about 10,000 daily steps then declined much more slowly. Plus, higher step intensity predicted even lower risk of all-cause mortality and cancer beyond that linked to 10,000 daily steps. More specifically, getting 10,000 daily steps predicted a significant 55 percent risk of all-cause mortality and 30 percent lower risk of cancer. The take-home message: 1) any amount of physical activity is healthful, 2) more is better, and 3) more vigorous is better than less vigorous. Get on the Keep Moving bandwagon from where are right now and over time increase the length and intensity of your daily physical activity. You’ll be glad you did.
Physical activity may help breast cancer survivors
Increased physical activity predicts lower risk of developing breast cancer. A new study asked whether increased physical activity predicts reduced risk of mortality among breast cancer survivors. Participants included 315 women with an average age of 71 years who received a breast cancer diagnosis at least two years prior to the study’s inception and were members of a Kaiser health plan in California. Physical activity and fatigue were evaluated using validated questionnaires. Over a median follow-up of 8 years, 45 (14 percent) of the participants died. Compared to women in the insufficiently active category, those in the moderately active and active categories had less than half the risk of dying. Thus, women with a breast cancer diagnosis would do well to Keep Moving, even at a moderate level of activity.
Vigorous, intermittent physical activity and cancer mortality
Overwhelming evidence shows that Keep Moving predicts better health and lower risk of chronic conditions. Nonetheless, middle-aged adults have low participation rates in structured, vigorous physical activity. Researchers used objective data from wearable devices in the UK Biobank Study to determine if incidental vigorous, intermittent lifestyle physical activity (VILPA) of participants who didn’t report any physical activity would predict risk of premature death, cardiovascular disease or cancer. During an average follow-up of 7 years and compared to participants with zero VILPA, participants who each day had about 3 bouts of VILPA lasting one minute each had 49 percent lower risk of all-cause mortality. For cardiovascular disease mortality and cancer mortality, the comparable reductions in risk were 49 and 30 percent, respectively. Wow! While these results may seem implausibly good, this study aligns with results of previous studies of high-intensity interval training and intermittent stair climbing. Overall, two or three short bursts of VILPA lasting a total of 3-4 minutes per day predicted substantial declines in all-cause, cardiovascular, and cancer mortality. Can you find brief opportunities for vigorous physical activity, such as stair climbing, in your daily life?
Better cardiorespiratory fitness may reduce cancer risk
Regular physical activity predicts lower risk of certain types of cancer. Improved cardiorespiratory fitness is a key desirable outcome of increased physical activity, especially at a vigorous intensity. Advancing age is a risk factor for colon, lung, and prostate cancer. Researchers in Sweden used data from 177,709 men with an average age of 42 years from the Health Profile database to see if increased cardiorespiratory fitness would affect their risk of developing or dying from cancer over an average follow-up of 10 years. Participants were grouped in four categories from very low (< 25 mL/min/kg) to low (25-35 mL/min/kg) to moderate (35-45 mL/min/kg) to high (>45 mL/min/kg) cardiorespiratory fitness. These objective data came from cycle ergometers in a clinical setting.
Compared to men in the very low category, those in the moderate and high categories had 28 and 37 percent lower risk, respectively, of developing colon cancer during follow-up. The risk of dying of lung cancer fell by 59 percent for participants in the high compared to very low category of cardiorespiratory fitness. Compared to men in the very low category, the risk of death due to prostate cancer declined by 43 and 71 percent for men in the moderate and high categories, respectively. Thus, ramping up your cardiorespiratory fitness with vigorous aerobic exercise might reduce your risk of developing lung cancer and dying of lung or prostate cancer.
Tiny amounts of daily vigorous physical activity can reduce cancer risk
Greater amounts of physical activity, especially at vigorous intensity, predict lower risks of developing cancer. Researchers used data for 22,398 participants with an average age of 62 years in the UK Biobank Study to see if tiny amounts of vigorous physical activity (3.5 – 5 minutes per day) would predict lower risk of any type of cancer and those cancers associated with lower physical activity. Importantly, participants reported no physical activity. Participants wore accelerometers on their wrists to objectively measure small bouts of vigorous physical activity. After an average follow-up of 7 years, participants with zero measured vigorous physical activity per day had an absolute physical-activity related cancer risk of 60 per 10,000 person-years, while the risk for participants with 5 minutes of vigorous physical activity per day was 40 cancers per 10,000 person-years. After adjusting for confounding factors, participants who got 4.5 minutes of vigorous physical activity per day in bouts of 1-2 minutes each reduced the risk of physical activity-related cancers by 31 percent. A small investment in your daily vigorous physical activity could substantially reduce your risk of cancer.
What to do
Find ways to increase your level of daily physical activity, especially short periods of vigorous activity.
