I have just acquired the basic computrainer set-up which includes ‘windtrainer’ and small display unit…no computer software…In essense I can measure watts, heart rate and cadence…
This is my first experience with wattage…What three suggestions can you give me to design my training program?
Buy the software from CT.
Buy Cycling Peaks Sofware.
Subscribe to the Topica Wattage list and to the Computrainer list.
-Robert
Read the articles at cyclingpeaks software:
http://www.cyclingpeakssoftware.com/power411.html
especially “How to train with Power”.
I’ve read them. 
-Robert
Is the Topica list on Yahoo also?
You should definitely buy the Computrainer software. You are missing out on spinscan, which is one of the best things about a CT. You are also missing out on the ability to program in your own power-based workouts and tests. (I realize you can get close to this with the small unit, but it is not the same.)
If all you need is wattage and HR, there are much less expensive units that provide this information.
Understand also, that there is a generally accepted delta between a CT and what you would read on and SRM or PowerTap. This delta is most commonly -20 to -30 watts, i.e. if you ride at 200 watts on the CT, most folks would find an SRM or PT to read 220-230 watts riding at the same intensity. There have been several folks on the Topica list corroborating this discrepancy by riding at CT while having either an SRM or PT mounted as well.
This doesn’t make one lick of difference to you, individually, unless you later decide to get an SRM or PT. You’ll need to adjust your workouts when moving from indoor to outdoor with regard to what values you use for your training zones.
My CT read 28 watts different than my PT. Therefore, when my upper Z2 on the CT (based on testing) was 200, then in order to ride the same intensity outdoors on the PT, I had to ride at 228.
The explanation for the discrepancy lies in where you are measuring watts. SRM and PT are reading power in the bicycle drivetrain, closer to the power source. The CT reads through the tire/roller interface. There is a certain amount of power loss at that juncture due to tire slip on the roller. Both units can be calibrated and there will always be a discrepancy.
Where you measure the power is unimportant, as long as power is measured consistently.
I guess the bottom line here is that if you have friends who have SRM or PT and tell you they ride X watts, you have to remember that their values are not directly comparable. Until I got my PT I didn’t understand this and would get discouraged testing a CP 30 at, say 280 watts and yet guys I had no trouble riding with were testing over 300. I got my PT last year and my first CP30, within days, increased about 25 watts. That’s when I tested the two units against each other to determine my particular delta.
Pardon the ignorant question, but if you can calibrate the CT, couldn’t you just “miscalibrate” it to read the same values as the PT? Just wondering.
You can’t calibrate the CT. It has to be calibrated by them. Keep in mind the calibration I’m talking about here is NOT the calibration done every time you get on it (due to fluctuations in pressure at the wheel contact patch). This is determined by actual measurements, and cannot be altered, except by cranking up the flywheel or putting more air in the tires. You cannot change the numbers. . .therefore, whatever is measured is turned into a numerical output that the firmware uses to determine wattage from.
You are correct in most cases about the wattage differential between the PT and Computrainer. For some reason, my CT and PT agree to within 1-2 watts on all rides over about 10 minutes until about 2 hours into the ride at which point the PT starts reading slightly lower (about 4 watts at 3 hours).
I don’t know how I did without these two tools though. With Cycling Peaks Software’s analysis functions you always know know what you did when in the ride.
Interesting experience. The electronics and mechanical tech in me is highly curious as to which unit is actually drifting, and why. I suspect the CT, due to the greater heat buildup, but without proper schematics and test gear. . .
Without totally hijacking the thread, I’d like to hear more about the Cycling Peaks software. I’m on the cusp of buying it, but being a Mac owner, it involves a little more cash outlay than for just the software.
Download the free version to a pc and play with the included demo files. It uses TSS and IF (training stress score and intensity factor) to help you determine your past and prospective training loads. Also, would you like to know how consistent your application of power was during a ride? All the graphs will be there PLUS normative power, which is the power you would have achieved with an evenly paced effort (roughly speaking). Would you like to know what your average power is over 5 seconds, 30 seconds, 1 minute, 30 minutes, one hour, or any other time interval? It’s there. Watch your power rise over time (unless you’re my age) with a graphs that plot your past year’s average wattage or your past month’s wattage, or almost any time variable.
This software is a quantum leap in understanding the numbers behind your training and in training properly. Simply put, the folks who use it are training smarter, IMHO.
If you have any doubts, email Andy or Hunter at CP and ask them.
-Robert