Effect of High Intensity workouts on Drag Factor?

[Knightsrower]

Do High Intensity sprint workouts have any negative effect on drag factor on Concept2 rower? I just realized that drag factor on my erg (when damper is 10) is significantly lower when compared to earlier values since I did many 100m, 500m, 1000m, 1m and 4m sprint workouts during June and July. I always clean my erg after each session and do regular basic maintenance. I don't think it was due to dust or any other reason like altitude or location in room since I always workout at the same spot. I had recorded my drag factor values when I did fan cage cleaning after 4 years of moderate usage one month ago. Values are as the following when damper setting is 1 and 10 respectively.

August 2016: 70 -207 (brand new)
June 2020: 69 - 205 (after fan cage cleaning)
July 2020: 69- 192

I know that ergs absorb dust much quicker in gyms but high intensity crossfit trainings might have also an effect on those low drag factor on ergs in gyms. I have absolutely no issue with those values since they still seem OK for my workouts but I just wonder your opinions regarding the significant change of drag factor due to change of intensity of workouts. Thanks.

[MartinSH4321]

I do regular sprint sessions but haven't recognized such an effect.
Is it much hotter now at your erging place? Warmer air will result in lower drag, but I don't know how big this effect is.

[Carl Watts]

You think its clean but its not.

Those tiny holes in the stainless get slowly obstructed reducing their diameter. You need like a paintbrush and put the stainless in soapy water to clean it and hit it with compressed air to get it back to the new readings.

Reality is it doesn't matter as long as you can still set the lever to the drag factor number you need.

Ergdata is great it records your DF in your results you upload to your logbook so you can just bump the lever now and again to keep it constant.

[Citroen]

Is it much hotter now at your erging place? Warmer air will result in lower drag, but I don't know how big this effect is.

Not enough to notice.

Elevation has the biggest effect. Ambient temperature and pressure has an unmeasurable effect.

If you set the drag factor using the reading from the PM5 or from Ergdata then it doesn't matter where the lever is set.
https://www.concept2.com/service/monito ... rag-factor

When you find the lever needs to be set higher and higher to get the same drag factor then it's time to open the cage and clean the dust and cruft out of it (which won't be very often for a home machine).

It really is as simple as that.