Are 11 Minutes of Exercise Enough to Extend Lifespan? New Study Suggests Short Bouts of Exercise Reduce the Risk of Mortality
In the short time that it takes to eat a sandwich, take a shower, or watch half of a sitcom on Netflix, you may be able to increase your lifespan — even if you spend eight hours per day parked on the couch. Although it’s well-known that excessive sitting is harmful to health — remember that catchy slogan “sitting is the new smoking”? — a new study indicates that at least some of the damage caused by a sedentary lifestyle can be mitigated with small bouts of exercise.
In contrast to the American Heart Association’s recommendations to exercise for 150-300 minutes per week, or previous research that suggested 60-75 minutes per day, a new study finds that just 11 minutes of moderate to vigorous physical activity — and not necessarily all at once — may do the trick.
Although the results of this study do suggest that exercising for 35 minutes per day is the most beneficial for longevity, aiming for 11 minutes per day can be a reasonable and achievable goal. Especially in this time of social distancing with many working from home — not to mention the shortened days with limited light — exercising for this small fraction of an hour might be a practical solution for most.
Using Fitness Tracker Data to Assess Mortality Risk
Published in the British Journal of Sports Medicine in November 2020, researchers gathered and re-analyzed the results from nine prospective cohort studies. With data from over 44,000 adults from four countries, this study looked at how time spent active versus sedentary plays a role in lifespan, specifically with the risk of premature death.
The individuals in this study, mainly from Europe and the United States, wore accelerometers to track their daily movements and capture the intensity of physical activity. These devices are similar to those embedded in a myriad of hand-held electronic devices, where they are responsible for flipping the screen when rotated. Essentially, accelerometers are fancier Fitbits.
This method is in contrast to other research that uses data from self-reported physical activity and sedentary behaviors. As you can imagine, self-reported behaviors are prone to error. (When it comes to diet and exercise, we tend to think we’re doing a little — or a lot — better than we actually are.)
The accelerometers monitored when the study participants reached an activity level defined as moderate-to-vigorous physical activity (MVPA). For most people, moderate-intensity exercise includes brisk walking or bicycling, while vigorous activity may entail jogging, running, or playing competitive sports. It even logged short bursts of activity, such as climbing a few flights of stairs.
Armed with the accelerometer data from tens of thousands of adults, the research team categorized the individuals into one of three levels for both sedentary and active time, creating nine possible groupings. For example, one who was extremely active and rarely sat would be in the top third for activity and the bottom third for sedentary time.
The Results: More is Best, Medium is Good Enough
On average, the people measured in this study spent approximately 16 minutes performing MVPA per day, with almost 10 hours per day spent sedentary. To briefly describe the different categories, the low, medium, and high exercisers spent 2, 11, and 34 minutes per day moderately or vigorously exercising. To categorize those spent in sedentary time, the low, medium, and high groups spent 8.5, 9.4, and 10.5 hours sitting, respectively.
With many of us tied to our desk chairs for eight or more hours per day — add in mealtimes, relaxation, and perhaps a commute — you may be wondering if your brief daily exercise is enough to reverse the detrimental effects of a sedentary lifestyle. Fortunately, the results of this study indicate that this may be true.
First, the bad news: not surprisingly, people who logged the lowest amount of activity (2 minutes) and the highest amount of sedentary time (10.5 hours) had a 260% increased risk of death from any cause, compared to those who exercised the most and sat the least. Regardless of the time spent sitting, those who were active for just 2 minutes per day had a significant increase in the risk of premature death, no matter which sedentary group they were in.
Things started to look up when the researchers analyzed those in the middle group of activity — the 11-minute people. They found that those who were active for 11 minutes per day and had the lowest level of sedentary time (8.5 hours or less) were not significantly different in terms of mortality risk compared to those who exercised 34 minutes per day and sat the same amount. These results indicate that despite sitting for over 8 hours per day, short activity bursts totaling 11 minutes throughout the day benefit lifespan comparably to people clocking in over half an hour.
However, once the sitting time exceeded 9 hours, the risk of mortality started creeping up concurrently. In those 11-minute exercisers, the risk of death was increased by 5% for the least sedentary, 31% for the middle third, and 68% for the highest third of 10.5 hours or more of sedentary time, compared to those with the highest physical activity and lowest sedentary times.
Lastly, health outcomes were the best for people who exercised the most. In this 34-minute group, it didn’t matter which sedentary group they fell into — all of the people in this category had similarly low levels of mortality risk.
However, it’s important to note that, as is the nature of observational studies, it can’t be determined that low levels of exercise cause death. It just indicates there is an association between sitting more, moving less, and dying earlier.
Essentially, if you sit for 8.5 hours per day or less, 11 minutes of moderate-to-vigorous physical activity per day may attenuate your risk of premature death. If you’re in the 9-hours-plus crowd of sedentary people, aim for about 35 minutes per day of exercise to increase lifespan.
In contrast to previous research, this 30-40 minute exercise sweet spot can provide you with health and longevity benefits no matter how much time you spend on the couch binge-watching shows throughout the rest of the day. (Although we don’t necessarily recommend this habit!) And, no matter what, aim to get your heart pumping for more than 2 minutes per day.
With that, there’s my — and your — reminder to get up and move!
Ekelund U, Steene-Johannessen J, Brown WJ, et al. Does physical activity attenuate, or even eliminate, the detrimental association of sitting time with mortality? A harmonised meta-analysis of data from more than 1 million men and women. Lancet. 2016;388(10051):1302-1310. doi:10.1016/S0140-6736(16)30370-1
Ekelund U, Tarp J, Fagerland MW, et al. Joint associations of accelero-meter measured physical activity and sedentary time with all-cause mortality: a harmonised meta-analysis in more than 44 000 middle-aged and older individuals. Br J Sports Med. 2020;54(24):1499-1506. doi:10.1136/bjsports-2020-103270