Measuring Your Fitness
It’s something every runner wants to know. Just how fit am I right now?
Measuring fitness isn’t something that the average runner has been able to do until just recently with the advent of heart rate monitors, and GPS. That combination of pace, distance and heart rate can provide a way to calculate a rough estimate of your fitness level at any given time.
Garmin vs. Strava
If you have a Garmin watch with a heart rate monitor (either on the wrist or a chest strap), you might have seen the VO2 Max number on your Garmin Connect profile.
VO2 Max is the maximum rate of oxygen consumption during exercise, measured in millilitres per kilogram per minute (ml/kg/min). The average person might have a VO2 Max of about 45ml/kg/min while a high performance athlete might hit 60 or higher. While the Garmin VO2 Max is just an estimate, it does provide a general idea of your current fitness level compared to the rest of the population.
Over on Strava, there’s a Fitness and Freshness metric available to Strava Premium members. This recent addition to Strava gives runners a number that represents overall fitness level, as well as form and fatigue values. How Strava arrives at their specific numbers isn’t really super important, but once you track your Fitness score over time you can see whether you are trending upwards, downwards or staying about the same.
Which one is best?
My VO2 Max on Garmin is about 55ml/kg/min at the moment and doesn’t really move around that much, even when I feel like I’m less fit. I’ve been as high as 58ml/kg/min and as low as about 52ml/kg/min over the past two years.
On the other hand, my Fitness score on Strava does seem to be a good reflection of how I feel at the moment and seems to track training nicely. Currently I’m at 39 on Strava and trending upwards which makes sense as I’m ramping up my training efforts heading into the marathon training schedule for the 2018 BMO Vancouver Marathon in May.
Looking back over my graph of the past year (above), I can see increasing fitness right up to where I fell and broke two ribs. Then it drops quickly, before building back up as I resumed running. The 2017 BMO Vancouver Marathon is the high point at 64 and then things dropped off over the summer as I took it easy and didn’t run as much, or as hard.
That graph seems to confirm that I lost a fair bit of fitness thanks to the layoff as the ribs healed, but that it came back fairly quickly once I was able to start running again. It’s about what I would have expected and guessed that the impact was.
Using Strava Fitness to measure training effect
With Vancouver now 22 weeks away, I’ll be watching the Strava fitness score closely to see how I’m progressing. I’m interested to see the impact of hill training and also the longer Sunday runs as training ramps up.
I hope to be at around 70 or 75 on May 6, 2018 when I race.