According to Lance Armstrong's coach, Chris Carmichael, Lance dominates because he has a high power output at lactate threshold.

In other words, on long, fast ascents, Lance isn't gasping while other riders are. Then on the final climb, he has more in reserve.

Build your own lactate-threshold power this winter by doing 20-minute, time trial-like efforts on the road, trainer or in combination. Once or twice a week is enough.

How hard should these efforts be? The neat thing about this training technique is that it's automatically personalized and doable for everyone.

A workout hinges on a simple scale that rates effort from 1 to 10:

Five is moderate activity such as walking fast or spinning along a flat road. Six is experienced as "brisk effort." At 7, you begin to breathe deeply but rhythmically and conversation is more difficult. At 8, your breathing intensifies and talking stops. When you're gasping, you've reached 9.

10? You don't want to know.

Fit riders time trial between 8 and 9. For winter workouts, dial it back a bit to between 7 and 8. You should not be able to talk easily but your breathing should still be in control -- not at the point of panting.

Reach this level and strive to hold it for 20 minutes. They just might be your most productive 20 minutes of each winter week.