Dr. McDougall's Online Discussion Board

Hello Jeff,

Hope you are well.

I am having trouble understanding the conclusion of this study.

There was a significant decline in SIT MCAv (-3.2±1.2 cm.s-1) compared to 2WALK (0.6±1.5 cm.s-1, p=0.02), but not between SIT and 8WALK (-1.2±1.0 cm.s-1, p=0.14). For CA, the change in 2WALK very low frequency phase (4.47±4.07 degrees) was significantly greater than SIT (-3.38±2.82 degrees, p=0.02). There was no significant change in MCA or carotid artery CVR (p>0.05). Results indicate that prolonged, uninterrupted sitting in healthy desk workers reduces cerebral blood flow, however this is offset when frequent, short-duration walking breaks are incorporated.

I currently spend 10 hours a day sitting in front of a computer. Over the past month I have been breaking those sitting periods up by walking for 6 min every 1.5 hr.

Do the results of this study suggest that I might do better by walking for 2 min out of every 30 min, instead?

Or am I reading this wrong?

Cheers,

In that thread, I posted several articles over a few years all pointing to the same thing, don't be sedentary and, taking short activity breaks throughout the day can really help. As a guiding principle, that stands.

In the study you mention, they looked at a longer time period (over an hour) and you you are correct about their conclusion. In most of the others, the time period was either 30 minutes or 60 minutes.

If you feel like shortening your time period to one hour, no harm done.

However, I would not be alarmed about it as I would be more interested in your total activity/exercise times and times being sedentary. That is the main point.

It's like the high intensity interval studies, you can go crazy trying to figure out the perfect formula for them

I hope that helps
Jeff

JeffN wrote:However, I would not be alarmed about it as I would be more interested in your total activity/exercise times and times being sedentary. That is the main point.

It's like the high intensity interval studies, you can go crazy trying to figure out the perfect formula for them

I hope that helps
Jeff

That helps quite a lot! Thank you!

That's the message I got from the earlier posts in that thread... but then I started second-guessing myself when I read the last study.

My current approach is working very well, and I feel that it is sustainable, so I'll stick with that. (Minimum of 30 min/day, 6 days a week... but with additional movement as time allows -- rowing, dancing, hiking. Current movement: around 4-7 hours a week)

Thanks, again, for all your hard work!

Cheers,