Cycling and bicycle racing discussion forums.   View New Forum Topics
Today's Forum Topics

Set as homepage


Go Back   Cycling Forums > Tech Corner > Power Training
User Name
Password
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read


Welcome to CyclingForums.com

You are currently viewing our website as a guest which gives you limited access to view most discussions. You will have to register before you can post to this thread.

By joining our free online community you will have access to post new topics, communicate privately with other cyclingforums.com members (PM), respond to polls, upload photos and access other special features like product reviews and classifieds.


Fluid trainer linearity v. time

Reply
 
Thread Tools Search this Thread Display Modes
Old 14-11.-2005, 08:43 PM   #1
886014
Registered User
 
Join Date: Mar 2005
Location: Sydney
Posts: 129
Default Fluid trainer linearity v. time

I have just installed a Polar Power sensor as my first introduction to power training and am just trying to get used to the idiosyncrasies of the unit.

I have a Travel Trac Century Fluid trainer and today tried some intervals. After a 10 minute warm-up at around 180W I did 8 intervals at a constant speed and cadence for each interval. I noticed the power indicated dropped for the first 4 intervals, then seemed to stabilise for the next 4 intervals.

I was wondering if the fluid trainer tends to provide less resistance as the fluid gets hotter with each interval (up until a point) or whether I have a lot more to learn about using the Polar?

Cheers
886014 is offline  
Reply With Quote
Old 15-11.-2005, 12:35 AM   #2
frenchyge
Registered User
 
Join Date: Apr 2005
Location: Kansas City, USA
Posts: 3,691
Default Re: Fluid trainer linearity v. time

Quote:
Originally Posted by 886014
I was wondering if the fluid trainer tends to provide less resistance as the fluid gets hotter with each interval (up until a point) or whether I have a lot more to learn about using the Polar?

The resistance will decrease as the temperature rises. My trainer boasts the "lowest operating temperature in the industry" and I see about a 2.5% drop in power (well, really a 2.5% increase in speed to maintain power constant) over a set of 6 VO2max intervals (after a 10min warmup).

I also seem to recall seeing occasional comments about Polar power readings in high gears or on trainers, so there may be something there as well.
frenchyge is offline  
Reply With Quote
Old 15-11.-2005, 12:54 AM   #3
886014
Registered User
 
Join Date: Mar 2005
Location: Sydney
Posts: 129
Default Re: Fluid trainer linearity v. time

Thanks. BTW the indicated speed and cadence (from my computer) were held constant and the same gear used for each interval ie precisely the same bike configuration. I'm presuming the viscosity of the fluid is decreasing with increased temperature hence providing less resistance(?)
886014 is offline  
Reply With Quote
Old 15-11.-2005, 01:02 AM   #4
frenchyge
Registered User
 
Join Date: Apr 2005
Location: Kansas City, USA
Posts: 3,691
Default Re: Fluid trainer linearity v. time

Right. As the temperature rises, the viscosity of the fluid decreases and you'll see a drop in power during your constant speed intervals. I ride constant power intervals, so I notice the same thing causing an increase in speed for me.
frenchyge is offline  
Reply With Quote

Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump



All times are GMT +10. The time now is 07:36 PM.


Powered by: vBulletin Copyright © 2000 - 2008, Jelsoft Enterprises Ltd.
Copyright © 2001 - 2006 cyclingforums.com

Links to websites we like:
Pezcyclingnews | Cyclingnews.com | Wine Zone | iinet