top of page

Don't Trust the Numbers!

Numbers are there to guide us not to tell us what to do.

For those of you who know me or have been reading my blog might find the title of this a bit alarming especially coming from me. I am an analytical person and love numbers, I have written a number of blogs here that talk about the importance of FTP, TSS, HR, Training Zones and now I am telling you not to trust numbers. 🤦‍♂️

The title is a bit misleading and is really not telling the whole story. What I want to talk about is when NOT to let the numbers drive us; when we should trust our “feel” more than our eyes. In training a lot of times we use our numbers (power, pace and/or heart rate) to help make sure we are working hard enough and at times that we are not working too hard. Today I want to talk about how those numbers can work against us at times; like when we are racing or testing.

There is no denying that testing for your FTP and setting proper training zones is important. I have also talked about why it is important to also track heart rate during your training. But there are times when you need to put that information on the second screen of your computer. When you are racing and testing you need to put more trust in your Rate of Perceived Exertion (RPE) and go by feel. Remember that our zones we get from testing are called “Training Zones” and not “Performance Zones” for a reason.

Let’s use me as an example. Currently my focus is on racing my bike on the road and I have a 280 FTP with a HR Threshold around 163. I do two or three indoor structured rides on the trainer weekly with the rest of my riding outdoors. When I am training indoors I am very focused on both my power number and HR; I use my power number as my driver/goal for the interval and track how my HR responds.

During a typical indoor workout when I am in an interval between 85-100% (240-295 watts) for 15 min my HR will be right around 160-164 and I feel like I want to die. This is week in and week out; I have come to recognize that being in that power zone and when my HR is around 160 I am suffering and I am not sure I can last much longer. Then I did a private race on Zwift with just my racing teammates; we broke up into two teams of 5 and we tried to set up someone from our sub-team to win just as we would in a real world race. It was hard. I approached it like I would a race which means I try not to look at my data. I just do what the race dictates; stick with the moves or get dropped!

At the end of the race I looked at my data for the 30 minutes of the “the race is on!”; I averaged 278 watts with a 168 heart rate. So if I compare that to my typical weekday hard workout I held more power for longer with a higher HR. Does this mean I just push harder in races? Do I not push hard enough in training? Are my numbers wrong?

Yes I do push harder in a race, no I probably don’t push hard enough in training and my zones probably should be a bit higher; especially my HR zones. BUT when I am in the race it doesn’t feel like I am pushing harder so am I? What is harder? Is it a measure of power or is it a measure of suffering? Number wise yes I pushed harder but feeling wise it didn’t feel any harder than a typical Tuesday morning trainer workout. Do I push hard enough in my workouts? Hell yeah I do; I typically struggle to make it through all of the intervals. Are my numbers wrong? No! My training zone numbers are certainly right for training but maybe not for racing. Those training zones are right for my indoor sessions but they might not be right for my outdoor rides. Just maybe we are not really comparing apples to apples when we look at racing vs. training or even indoor vs. outdoor riding.

What I am getting at here is to remember that racing is not training and training is not racing. If you approach racing the way you approach training then it is simply just another training day. And if you approach training like you should approach racing you will never get the gains you are looking for. Racing is a chance for us to express our fitness, training is how we gain our fitness.

Don’t approach the two things the same. If you finish your workout and are disappointed that you didn’t run as fast as last week or didn’t get a PR on that climb then you are looking at your training like a race. If you show up to a race and are dead set on staying in this certain power range even though the field is pulling away then you have just turned that race into a training session.

If I would have been looking at my numbers during that Zwift race and noticed I was holding close to my FTP with a HR above 165 and still had 20 minutes to go I would have not believed I could hold on; and I would have been wrong. If you get that fracture of belief in your head, “I can’t do this”, when the race gets tough you are certain to crack. We all have that little jerk in our head that tries to convince you that it is okay to ease up and doesn’t believe that you can keep going. The numbers on our screens can give that jerk more of a voice at times. That jerk is loud enough; you don’t need to give them a megaphone.

Bottom Line: Racing is about testing yourself physically, mentally and emotionally. I don’t know how many times I have said to an athlete on race day “Trust your fitness.” What that means is you have done the training, the work, now just go out and use it. Don’t overthink it. Don’t worry about what you are supposed to do; just get out there and do. Trusting also means that you mentally believe in yourself so don’t let the numbers on a screen tell you otherwise. At the end of the day it doesn’t matter what place you got or your overall time, what matters is that YOU feel that you gave it your best out there on that day. That you are proud of yourself. That in those moments of doubt when that jerk is yelling in your ear to ease up that you told them to F’ off.

Keep moving forward.

Brian Hammond


Recent Posts

See All


bottom of page