IDT - RPE v Watts v Gradient - help please

[Spirog]

I'm really loving training on my new Cycleops Jetfluid IDT. It is an upgrade from a spinning bike I had and the ability to see real effort (read watts) instead of perceived effort is fantastic. I'm sure that I'll see real benefits very quickly.

 

I'm using the Virtual Training software on PC

 

Dave from Bicycle Power gave me a great spreadsheet to convert RPE to Watts for the Sufferfest videos and this is a great feature. It looks something like this: RPE Watts Percentage 3.0 100 50% 3.5 111 56% 4.0 123 61% 4.5 134 67% 5.0 146 73% 5.5 157 79% 6.0 169 84% 6.5 180 90% 7.0 191 96% 7.5 203 101% 8.0 214 107% 8.5 226 113% 9.0 237 119% 9.5 249 124% 10.0 260 130%

 

My question:

When riding a downloaded route on VR is there a corelation between Grade/Slope and Watts? So, for example when VR riding a 7% gradient, what should the RPE or Watts be?

 

I'm not sure the question is logical or intelligible.

[Sharkie 2]

You should be able to either ride at 400watts or 200watts or whatever not so?

As it it depends on how hard you want to ride the 7%.

[Spirog]

You should be able to either ride at 400watts or 200watts or whatever not so?

As it it depends on how hard you want to ride the 7%.

Yes, but if I'm riding at a constant pace how does that change with the grade. Let me try another way. I'm riding on the flat at a RPE of say 3.0. The grade kicks up to 5%. What is the correlation in watts or RPE between these. Am I making sense?

[Thomo]

Yes, but if I'm riding at a constant pace how does that change with the grade. Let me try another way. I'm riding on the flat at a RPE of say 3.0. The grade kicks up to 5%. What is the correlation in watts or RPE between these. Am I making sense?

 

Forget about 'pace' when training ... ride only watts. (+ HR)

As sharkie 2 also suggested, decide what watts to ride for a specific elevation. (determined by your FTP)

[Spirog]

Forget about 'pace' when training ... ride only watts. (+ HR)

As sharkie 2 also suggested, decide what watts to ride for a specific elevation. (determined by your FTP)

I agree with what you're saying. However how do I determine what those watts should be on a particular gradient? I want to make them consistent. I ride with HR and my VR programme uses cadence and speed to determine a wattage.

 

Or asked another way - If 0% gradient is say 100 watts, what should 3% be in watts? Or 5%? etc. Is there a spreadsheet that determines what the correlation is?

[TALUS]

Mate, You are overthinking this. Watts must be as high as possible! Actually it is determined by your weight and the speed you are going at (amongst many factors). Also I think is a logarythmic (or something) curve...

[Thomo]

I agree with what you're saying. However how do I determine what those watts should be on a particular gradient? I want to make them consistent. I ride with HR and my VR programme uses cadence and speed to determine a wattage.

 

Or asked another way - If 0% gradient is say 100 watts, what should 3% be in watts? Or 5%? etc. Is there a spreadsheet that determines what the correlation is?

 

Sorry - unfortunately I'm not familiar with the conversion program you're running.

Generally there is a direct relation between gradient and watts, but and inverse relation to speed/cadence.

So as gradient increases, watts increase, but speed decreases.

Your program however seems to rely on increases in speed and cadence to determine increase watts.?

[Help.Me.]

sorry for the hijack: If i look at my Garmin "results" and the profile shows a hill and i take the time to climb that hill at an avg heart rate and i mimic the time and heart rate on my IDT does it have the same effect as cycling up that hill??

[Spirog]

I'm now worried that I'm asking a really stupid question. And asking it badly.

So, I'll try again.

 

My programme is Virtual Training. It uses cadence and speed from the Garmin sensors to tell me what my theoretical wattage is. I ride on a virtual courses that I've downloaded off the net. When the gradient changes, I should(?) be changing gears to create the feeling off riding up a steeper gradient. Now, the watts reading on the VT programme changes, but I don't know how much it should change by. (Again, I'm not sure the question makes sense)

 

What I want to be bale to do is have a factor that the wattage should change by for every pecent (or whatever) of dradient that changes. Then, when my FTP improves over time (hopefull), I will always be pushing the same amount of increase per grade even though at a higher theoretical wattage.

 

This is so convoluted that I'm now confused as to why I even started the thread!!

[Erroli8a8]

To work out watts for a % gradient you would have to maintain the same speed and cadence up the hill as you would on the flat, the higher the % gradient the higher watts need to be to maintain the speed.

 

you can maintain the same watts from the flat onto the % climb, by doing this your speed will drop.

 

there is no factor to work this out as you are the factor. if you can always maintain the same speed and cadence no matter how high the % goes then yes you can work out a factor but as long as you cant maintain this then there is no way to calculate a factor.

[Jakkals.]

What you are trying to determine is quite tricky.

 

This is solely your own responsibility to ride harder once the gradient goes up...

 

My advice for you is to gear down(make it harder) and maintain the same cadence as your normal ride cadence(95-100), your watts will increase.

[Erroli8a8]

use this as an example. http://www.kreuzotter.de/english/espeed.htm

enter the details and if you have the same speed you will see that the watts goes up.

I entered my details and to go from flat to 10% at 20Km/h the watts go from 95 to 715.

 

you could enter every angle and speed variation and get some chart with the watts on that you could look at.

[Spirog]

use this as an example. http://www.kreuzotte...lish/espeed.htm

enter the details and if you have the same speed you will see that the watts goes up.

I entered my details and to go from flat to 10% at 20Km/h the watts go from 95 to 715.

 

you could enter every angle and speed variation and get some chart with the watts on that you could look at.

Geez, that got complicated. Amazing, nearly 5 times that watts required to maintain the same sped at 7% as at 0%!!!

 

This was the answer I was looking for. Now if only someone had it in a nice Excel spreadsheet, it would be perfect.

[Spirog]

So, using this site, http://www.kreuzotter.de/english/espeed.htm I came out with this. FTP 136.0 SPEED @ 20 KPH GRADE WATTS 0% 68 1% 109 2% 152 3% 194 4% 237 5% 280 6% 322 7% 364 8% 406 9% 448 10% 491 11% 532 12%

574

I now have a relative figure to aim towards to make my VR training more realistic.Thanks hubbers!!

[Jakkals.]

So, using this site, http://www.kreuzotte...lish/espeed.htm I came out with this. FTP 136.0 SPEED @ 20 KPH GRADE WATTS 0% 68 1% 109 2% 152 3% 194 4% 237 5% 280 6% 322 7% 364 8% 406 9% 448 10% 491 11% 532 12%

574

I now have a relative figure to aim towards to make my VR training more realistic.Thanks hubbers!!

 

I would rather make cadence the constant, its a tad easier to control I reckon

[rouxtjie]

Nice thing about ergo trainers is that if you set a target wattage...lets say 220 watts...it will adjust the resistance to accomodate your cadence fluctuations