When I started using my Computrainer (CT) by Racermate, it was hard to figure out how to use. So I thought I would post some discoveries about it in the last 2+ years of using it while training.
The CT is great because it’s like weight lifting for the bike. The wattage settings are consistent with the CT from workout to workout; with a regular trainer, you aren’t consistent with the pressure the roller is pushing against the rear tire and you may not be working out as hard one day to the next. On the CT, a calibration step makes the wattage consistent from workout to workout.
Add to that the ability to ride simulated courses and you have the perfect companion for indoors training.
Here are some tips about it:
1. Make sure you go through the calibration step. You need to pedal at least 8-10 minutes to warm up the tire itself and then the CT will be calibrated to the rubber of the tire against the roller. When you hit both the +/- keys together, you enter the calibration mode. Then you pedal to at least 25 MPH and then stop pedaling until it stops. It will then reveal a number related to the tension of the roller against the rear tire. This will change from the beginning when the tire is cold to when the tire is warmed up. However, according to Marc Evans, he says that you can still have some variance in wattage consistency across workouts if you don’t push the roller against the tire with the same tension, and have the same air pressure in the tire. I am too lazy to make it consistent from workout to workout. I just calibrate as is. Marc inflates to 100 lbs and adjusts the roller until the unit says 2.00 during the calibration step.
2. Ergometer mode is where I do most of my workouts.
3. You can do a benchmark test to measure your fitness and give you a sense for your workout wattages, and tell you where approximately your bike LT is. This is a 2 minute 20 watt step test which is in the manual. Here is my benchmark from last year:

Record time, watts, HR and RPE. Change watts every 2 minutes by going up 20 watts until you can’t continue. My LT is around HR 174, where I really go labored.
It also told me that I can do 2-3 min intervals at about 170w-180w.
4. Generally interval workouts are about 30-60 minutes in length. I do usually 2, rarely 3, per week which is in addition to my long bike on the weekends.
There are ladders you can do, gradually increasing wattage progressions, and also see-saw type workouts where you have 2 minutes at high watts, and then drop 30 watts for a recovery, but not all the way down to spin watts (ie. 50-100).
5. Neural activation workouts which help you get used to more watts, are short intervals at high watts.
6. Strength workouts are done with low RPM but high watts and lots of rest.
7. My warmup usually includes the calibration step. So I’ll spin at low watts, 50-100 for 8 minutes, then enter calibration mode, calibrate, then exit calibration mode and raise watts to 100w until 9th minute. Then I’ll do :30 high watts, :30 low (100w), and steadily increase the high watts until I’m past my workout watts. Warmup is at a minimum of 15 minutes and better up to 20 minutes. I find sometimes that even though I warmup 15 minutes, my first few intervals are tough to handle, but I feel better as the workout goes on. But usually I’m time constrained so I only warmup for 15 minutes.
8. I have never tried doing an interval workout beyond 1.5 hours. It’s pretty hard and taxing to maintain that kind of strength for that long. My coach gave us all his mega interval workout of 2.5 hours. I have never tried it and don’t think I will ;-).
9. Spinscan is way cool. It’s great to practice neuromuscular training by focusing on creating perfectly round circles and even circles between the left and right legs. You can see the unevenness you may have in pedaling on this graph.
10. I also use Powercranks on my CT. It’s a great strength workout and helps in balancing the strength output between legs. Ergometer mode is perfect for adjusting watts during a workout. Powercranks workouts only last about 30 minutes. You’ll find they are much more taxing than normal crank workouts.
11. I don’t like to ride the 3D bike courses. You can’t coast downhill and uphills are super tough as the CT sometimes locks down on the rear tire on steep uphills. I do use the Challenge PC1 app and ride on simple rolling courses to practice maintaining constant wattage during a ride.
Here is a website with courses:
http://www.michiganoutlaws.com/computrainer.htm
One thing that helps on course rides is to make sure you jam the roller on the tire as much as possible, as sometimes the rear wheel slips against the roller on hills. This was from a Racermate rep I met at an Ironman expo in Kona one year.
Definitely one of the coolest, most useful training gadgets around.