How to Analyze MTB Power Meter Data from an XC Race
I don’t often win races. As a matter of fact, none of us win races often and some of us will never win races.
It’s a complicated thing, going fastest. It’s usually dependent on who shows up, how we feel and how the trails suit us on the day. We discussed this in-depth in one of our recent podcast episodes:
The funny part is that whether we are winning, in dead last or anywhere in between, we are usually doing our best. In a way, I consider MTB XC racing to be a lot like a time trial. Post-race data analyses help us understand what we did and then determine a training intervention to get better. This way we race, then train using evidence, then race again–and if all goes well we go faster.
Most riders will never show their power output or other data. Many consider this stuff too personal to share, and might even feel embarrassed because they don’t have amazing numbers like the pros. This means that whether we do or do not have a way to collect our own data, we still don’t know what to expect or where to start with analysis.
As we discussed before, there is a lot that goes in to going fast. You need to pedal hard, pace well and even brake efficiently. Therefore, power is only part of the story.
Since a lot of athletes do consider this personal, we won’t share their data right now. But until an athlete comes to me with absolute confidence to share their numbers, we can at least look at mine!
I am not the fittest or a very committed athlete, but I demand absolute excellence from my athletes! I’ve been there–you know, all committed and stuff. Now I am focused more on educating and building BrakeAce, and it shows in my power:weight ration. It isn’t what it used to be. And I’m totally fine with that! 🙂
So there is no ego here.
The race we are analyzing here is from a recent win at a local club winter series. I use the term ‘win’ a bit tongue-in-cheek because I know that the guys who had beaten me at the race before this were out racing the road and not at this race! There was still some tough competition and I had to keep pushing when I saw riders from other age groups through the trees. It was super close!
To give you a bit of insight into what kind of power other riders are doing and to understand what to look for when analyzing a race, I did a whole video analyzing my own race just like I would analyze any of my athlete’s files.
You can check that out below.
For added insight, here are my top tips for analyzing a MTB race file:
Start with Averages
The first thing I will do with any ride or race is check out the average power and heart rate, then also peek at max. Oftentimes with an experienced athlete on a training ride, this is enough to get a good idea of whether the performance was good or not, or as prescribed or not.
After that I deep-dive.
Average power is good for the road, but normalized power (look for the NP in the picture) is better for MTB. There are still issues with it though! Therefore it’s important to consider all factors.
Normally I highlight the actual race, check out normalized power and can quickly determine if it was good performance or not.
Look at pacing
Pacing is number one in XC racing.
FORGET THE START. The start barely matters.
I look at pacing from start to finish and everywhere in between. Since we don’t use gasoline as fuel and our legs are the engine, we need to use our very limited energy appropriately.
If the athlete didn’t hit the ‘lap’ button each lap, I highlight the race in halves, then quarters (or laps) to see how the athlete slowed or maintained performance. You can see that highlighting a section of the file changes the averages, peaks, etc so you can see how this changed.
Check out the lap analysis in the video below to see my pacing 🙂
Highlight key sections
Major climbs or descents are where races are often decided.
I’ll go through each major climb to determine how the athlete performed and continued to perform.
Highlight the first climb and last climb, then work your way into the middle comparing like to like. Again, look for averages, normalized power, peaks, etc.
Look at the trend of the heart rate
Whoops, I didn’t have a heart rate monitor!
Power is king in MTB–heart rate is pretty steady.
Still though, it’s good to look at. You can notice things like recover after climbs, cardiac drift, etc. All my athletes use power meter and heart rate monitors, and with all of this data I can feel like I was there with them on the ride no matter where we are in the world.
Is the warmup and cooldown sufficient?
Well, mine sucked! Actually this one is much better than the one from a month before that we analyze in the video, but it still isn’t great.
We need to warmup to increase the temperature of the muscle, reduce the oxygen deficit and reliance on anaerobic metabolism, and increase offloading of O2 from hemoglobin.
If you’re not going to warm up properly, then you absolutely need to start easy–no question!!
We discuss heart rate in one of our exclusive members-only content
There’s more
Of course, there is a lot more that goes into, but you can check out the video to learn more.
LEARN SPORTS SCIENCE ON THE PERFORMANCE ADVANTAGE PODCAST MASTERCLASS
Video
Here I analyze my own power. It doesn’t really matter what the numbers are, but these are the things that I’m looking for whether checking out pros or amateur performances.
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Getting the most out of your power meter
Pace yourself to the perfect race
Check out the MERCH for more