Login | January 02, 2025
How much sedentary time is too much
PETE GLADDEN
Pete’s World
Published: December 30, 2024
If you’re a regular aerobic exerciser and believe your cardio workouts more than compensate for all that inactivity you incur when at your work cubicle and in front of the TV, well, there’s some research out there that begs to differ.
That’s right, and for me it was kind of like watching a fastball blast across the middle of home plate as I stood there completely oblivious to it all.
The research I’m referring to can be found on the Nov. 15, 2024 web edition of the Journal of the American College of Cardiology.
The article, “Accelerometer-Measured Sedentary Behavior and Risk of Future Cardiovascular Disease,” concluded that more than 10.5 hours of sedentary activity per day (not including sleep hours) may very well increase the risk of cardiovascular disease and that risk also pertains to physically active people such as myself.
Now I do a lot of aerobic activities, probably far more than most folks need to even think about doing, but there are also times when I spend a good deal of time anchored to a chair in front of my computer working.
What’s more, I like to lounge away several hours a day reading and/or just plain chilling on the couch in front of the TV.
So I can say with certainty that my sedentary time typically far exceeds my active time.
By how much?
Well, I’d never really thought about the quantitative part of that question, but I can tell you this: I always figured that my aerobic activities more than compensated for any amount of sedentary time I might incur.
And that’s why after reading this study I literally sat there starring blankly at the floor in astonishment.
Okay, so the study was done in conjunction with the aforementioned JACC, and the researchers determined that, “sedentary behavior is broadly associated with future adverse CV [cardiovascular] outcomes, with particularly prominent effects on HF [heart failure] and CV mortality, where risk inflected at approximately 10.6 h/d.”
In normal people speak they’re saying that sedentary times of over 10.6 hours a day have been linked to higher rates of both heart failure and cardiovascular-related death.
And as I said, the kicker is that they found this also pertains to active individuals.
And when they say “active” individuals, the study’s referring to active in the sense that people are putting in 150 minutes or more of moderate-to-vigorous physical activity per week.
Now this was a study that entailed a meta analysis (combining the results of numerous independent studies to ascertain one predominant trend or result) of the UK biobank, a massive biomedical database that contains genetic, health and lifestyle information of participating UK residents.
Approximately 89,530 participants of the UK biobank actually took part in this study, with the average age being 62 years, and where 56.4% of the participants were women.
And finally, accelerometers were used to track the participants’ activity levels.
Now for regular aerobic exercisers like myself there’s a bit of anxiety relief here, because the researchers did report that for those physically active participants, the ramifications of sedentary behavior on AF and MI risks were greatly reduced.
But there’s still a BUT here, and that but is that more than 10.6 hours/day of sedentary time will still put active individuals at a higher risk of HF and CV mortality.
Another important note here is that according to the study’s authors there are still a few chinks in the armor of their analysis.
Primary among those chinks is the fact that the researchers were unable to determine whether such factors as lying down, sitting down and/or standing up in place for extended sedentary periods differed from one another with respect to CV risks - this because the accelerometers cannot differentiate between various sedentary postures.
And this would have a massive impact for individuals like myself who spend a good deal of time seated in front of a computer screen, in addition to all those folks who work while standing in place for long periods of time.
Nonetheless, the authors still advocate the importance of cutting down on anything over 10.6 hours of sedentary time per day.
Even replacing a paltry 30 min/day of that sedentary time with physical activity can reduce HF risk by 6% and CV mortality by 9% say the authors…which is something to think about if you’re amassing large amounts of sedentary time each day.
It’s definitely given me a little food for thought.