Yesterday, while recovering from my ride two days ago, I went back and dug into Alpine Cols’ excellent overview of training for the Tour du Mont Blanc. It’s probably the only one out there that is specific to the event, so it’s my good luck that Marvin did such a great job at it.

An interesting little bit of info that I’d missed on my first 10 readings popped out at me last night – a little chart on what VAM you need to finish within in a certain time period. But what is VAM, I hear you whisper. It is a handy metric that a client told me about many years ago and one that I honestly don’t pay much attention to…until now that is.

VAM is simply your Vertical Ascent in Meters per hour. This shows up on many segments on Strava, by the way, so you can go and see what you usually do on climbs and compare that with the sad story I’m about to tell.

Back to the guidelines – according to Alpine Cols’ calculations (I’ll do my own at some point), I’ll need a VAM of 600 to finish TMB within the 19 hour time limit. This comes to 13-14 hours of climbing and translates to approximately 1.9 W/kg (something I’m not measuring). This assumes some things, such as your ability to descend well and presumably an optimal total break time at feed zones.

The good news is that I’ve done climbs at over 1000 VAM in the past, but these were one-offs and not one of 6 or 7 riding all day and night. This was also before I put on the Covid pounds. The bad news is that right now I’m climbing (in Zone Two) at somewhere between 500 and 600 VAM, but only on 3-hr rides.

It’s important to know where you are so that you know what it’ll take to get to where you want to be, and it’s also nice to have a handy metric like VAM that you can see every ride. I’m sure that as my weight decreases and power goes up, the VAM will gradually rise. The great unknown is whether I can hold any VAM for 19 hours. That one we won’t know about till July 13th.