TT vs. Road Bike Power

Training Concepts
#1

Good morning,

I am writing this post, as this is a topic that interests me greatly, but I haven’t really been able to find an answer to adequately address it. It seems generally accepted that for some riders when they go from their road bike to their TT bike, there is a loss in power. This could be due to an over-aggressive position (such as being too narrow and not being able to breathe), or just not being used to riding in that position and not recruiting the muscles in the same way as you would on the road bike.

In podcasts and articles, there are discussions about how athletes have either closed the gap in the discrepancy, or even eliminated it all together by riding consistently on their TT bike. What is often missing in these stories about athletes is 1) how often are they actually training on the TT bike, and 2) what types of sessions are they doing on the TT bike (z2, temp, threshold, Vo2)?

For someone who wants to decrease the discrepancy, what type of approach would people recommend?

Personally, my thought is to start the season with all of my Z2 rides on the TT bike (with the added benefit that I wouldn’t be going too hard). Then after doing a solid base period, start progressing to higher intensities on the TT bike, while also still doing Z2 work on it.

I would love to hear other people’s thoughts.

#2

It’s been quite some time since I’ve heard it discussed, but I recall studies showing that a narrow position doesn’t restrict breathing after all, and even if it did, we can still take in more air than we can extract the oxygen from anyway. Reductions in power in the TT position aren’t an O2 delivery issue.

As for how often should you ride in your TT position to minimize the differential between TT power and road power, I would say first that it’s a good idea to make sure your position is optimal to begin with. If you’re aggressively attempting to maximize aerodynamics by going low up front, to the point that your power is diminished, it may be the case that you’d be far better off by raising the front end, not lowering it, and making sure you’re as narrow as you can comfortably be. Once that’s dialed, how much you ride the TT bike depends on how strong a priority you place on your TT performance. You could take the Bingham approach and ride your TT bike exclusively, or you could ride it once in awhile, or anywhere in between. As an aside, I’ve found that the nature of the riding you do on your TT bike matters, too. Me, I find that high torque climbing in the TT position works very well to bring up the power I can do on the TT bike. In my most TT focused seasons, I would climb on the TT bike at least once a week and had no decrement in power relative to my road power.

#3

Thanks for the reply. I’ve already been professionally fit and being too low is definitely not the issue.

I do not have any climbs around me whatsoever, but it is interesting you mention high torque climbs. After ever race, my glutes are absolutely fried (sometimes to the point where I question whether I will be able to drive my car home). I started incorporating lower cadence/high torque work on my TT bike mostly because whenever I do this in training, I notice my glutes really working hard. Now whether this is going to help or not, only time will tell.

#4

One thing that I found really helpful, heavy weight training specifically targeting the glutes. It’s key that you’re working very heavy in a low rep range. As cyclists, we already have the endurance capacity to fire our glutes repeatedly against relatively low resistance, so no need for higher rep ranges.