I was playing on a friends computrainer for the first time last night (what an awesome piece of kit). I want to tweak my bike position very slightly but what is the best test procedure for this ? Do you fix the wattage and look for a speed change/HR or fix the HR and check the wattage ? I assume you use a flat windless TT course but over what length for a quick snapshot ?
In other words, what is the best procedure !!!
If you visit the computrainer site www.computrainer.com they have a whole protocol on doing this, I think. If not, you can ask via email. There is a video that explains it too.
By the way, you are right about the training value of these. It is just incredible, and if you are training for a long tri, you can replicate it so closely that you’ll be amazed at the results.
The suggestion example (but not detailed) is to fix the HR and make a note of the output power ? Does this right. I guess you’d have to fix the cadence or some of the other qualities ?
Any more experience on this ?
I’ve never been able to play with one of these machines. What I’d like to do is to find a power output that seems to be the highest at a rate that I am able to sustain…note my Perceived exertion and HR, then move my seat forward (I’d have to raise it just a hair as I do this) and drop the front end lower, and see if my output stays the same. Fiddle until I find the spot where I am as forward as I can be and as low in front as I can be…then, move a bit lower until my power drops ever so slightly.
If I am still comfortable, it is at this point that I’d like to do real world, in the wind, up and down the hills testing. My thought is that the most powerful position may not yield the fastest time on the bike, it may be the most aero position that yields almost the best power could be faster…just something I’d like to do.
I’ve gone through the c-trainer fit suggestions and they are good to a degree. Once you have your fit close, the c-trainer is not going to measure fine enough to help you dial in your fit. There are 2 big problems, it takes a while for your body to become most efficient at a given setup and the c-trainer in no way accounts for lowered wind resistance.
It’s a good idea to check a couple fit ideas on the c-trainer but just remember the limitations.
Be careful using the Computrainer as a bike fit tool. It is a very myopic view of bicycle/body performance.
Sizing a person on the Computrainer is absolutely the best way to size them if all they are going to do is ride on a Computrainer.
When you modify the position to optimize power output on the computer you frequently wind up with a position that is too steep and too upright for practical road use. We have done literally five years of testing with using Computrainers as fit tools and find they offer limited benefit. There are benefits, but they are limited.
Aerodynamics and bike handling characteristics are an enormous part of what make a bicycle fast- between the two they may comprise of 60% of the total influence on the Performance package. Computrainer does not test for either aerodynamics or bike handling characteristics.
Setting your position up to be optimal on the Computrainer is an easy trap to fall into. All that data is alluring and it is easy to see changes in the data with changes in your position. That is exciting. But if you get caught up in the excitement too much you won;t have the opitmal position where it counts: On the road.
Stay focused on what you are trying to accomplish: a more efficient position that maximizes your sustainable power output and speed.
Use the CompuTrainer to validate that the position improves your power output (flat courses work best for this) and use various known outdoor rides to measure any improved aerodynamics & speed.
Measure, record, analyze, repeat. How else are you going to know?
Go get 'em-
-Mike Llerandi