On the value of metrics in sports

When discussing heart rate monitors for a friend's partner recently, he pointed out she might not see the value in it, and is quite happy going for a run with just a watch.

As someone who has collected gigaquads of data about my exercise over the years, I agreed there might not be much point, and thought about what value I have extracted from my data. As follows:

Sports Metrics

Cycling

• Neophyte: I collected speed, cadence and HR. Speed is fun, HR is HR, but the real value came from cadence: I spent a long time focussing on keeping my cadence at or above 80RPM. When cycling up steep hills, this forced me to switch into lighter and lighter gears, which allowed me to ascend much more efficiently.
• Adept: power is the standard evolution for cyclists. Once I added a power meter, I could expand my 80RPM cadence to more subtle fields, often aiming to maintain a 10-second average power of 180W, increasing to 200W if I'm in a cycling-focussed phase.
• Doyen: at this level, one starts to factor in temperature, and its effect on power output, and heat adaptation. I've spent less on this with cycling, as I rarely find heat to be as problematic on the bike, I think due to the increased amount of air flow cooling.

Running

• Neophyte: like cycling, the first metric that really improved my running was cadence, and coincidentally at 160SPM/80RPM. The underlying theory as I understand it is that with a higher cadence, the runner takes shorter steps, and the load per step is lower, reducing the probability of injury. This took me from misery to enjoying running.
• Adept: I think running is a sport it's best to, by-and-large, let one's body figure out how to run, and instead of focussing on in-session metrics, focus on long-tail analytics in trends. To this end, I have a protocol, Vigil, that looks and my left/right balance, tracks my personal asymmetry, and alerts me to a deviation from that band. My favourite for this is Stryd's Impact Load Rating Balance (ILRB), and it has signalled a problem I was having with my left quad before, during, and after.
• Doyen: again, heat, but I've become very specific with this, having accumulated a lot of runs while wearing a CORE body temperature sensor. The short of it is, on a hot (or hot+humid) day, I set my pace by my HR: I target 150bpm or less, and focus on reducing my pace when it's sustaining over 155bpm. This can add 1m 30s to my pace, but it means that even on a 33º day, I can run for an hour+ without the heat being the limiting factor.

Swimming

• Neophyte: this is becoming a habit. Cadence, again, this time I set my intensity by my cadence. 55SPM is cruising, 60 is moving quickly, 70 is someone has sighted something with teeth and I want to out-swim them. Over several years of swimming, these bands have held true almost regardless of fitness.
• Adept: understanding my HR in relationship to effort, I know that a maximum 136BPM is ~∞ sustainable (in that fantasy world of endurance sports, anyway). This is particularly useful at the start of a swim in cold water, even if monitoring it in cold water is more of a challenge.
• Doyen: really understanding my maximum HR in swimming is about 25BPM lower than that of running or cycling, and adjusting my zones accordingly.

Climbing (Indoor)

• Neophyte: observing how close to my maximum heart rate a route pushed me. The average indoor route is 2-3 minutes, so when I finish one at 178BPM, versus 140BPM, I know that was a hard route.
• Adept: I wore a muscle oxygen sensor on my forearm, and repeatedly climbed until I fell off. From these data, I was able to observe that I shouldn't resume climbing on a route until my HR has dropped below 145BPM. Above that, and whilst I might make progress, the probability of finishing was much, much lower. Below that, and I almost always made it to the top. (I know, part one. I never wrote part 2.)
• Doyen: work in progress across two domains here, heart rate variance as a recovery metric between routes.

Weight Lifting

• Neophyte: to determine the load of a session, ignoring everything aside from the total volume moved, and tracking that trend.
• Adept: like climbing, HRV is, I think, an understudied area of physiology in weight lifting. After analysing HRV trends over time, I have a loose protocol established of when to resume lifting after a set, and use it when I lift, in an app I made called Palæstra. I can complete the work faster than if I decide when to go again based on how I feel.

A note on HRV in exercise

I think most people know about HRV from Ōura, Whoop, Garmin, et al. An overnight metric measured with an optical sensor. This lower-resolution, long-tail measurement is less effected by movement, swallowing, and position changing, whereas with climbing and weights, moving the body, swallowing, breathing differently greatly changes the numbers. My control for this is holding the same position between each set: bench press, I'll sit up on the bench. Squats, I'll stand up. Climbing, I'll stay slumped in a heap. I realise it's not perfect, but, it's what I've got and so far it seems to be working.

Health Metrics

Calories

Roughly, 3200+ per day is a day I need to be mindful of recovery after.

Vigor Vitæ/Body Battery

Assuming I start the day at 95%+, 35% is an excellent percentage to start relaxing and being ready for bed, to be fully recovered for tomorrow.