My favorite (totally subjective) method to measure running intensity: listen to music and think if it sounds too fast. If familiar and regular beats sound like they’re going faster than I remember them to be, that means my brain isn’t running up to speed and my heart isn’t pounding hard enough.
Weird, yes, but it actually works! I can start a run listening to a song and finish a run hearing it (subjectively) 10% slower. I don’t know what an endorphin rush is supposed to feel like because I mostly just feel (subjectively) crummy after running, but at least I take comfort in knowing that my mind is running more smoothly because of the exercise.
Music is also part of my favorite way to track run duration: number of tracks in an album listened to. This started back in Santa Barbara when I challenged myself to run through all of Daft Punk’s Discovery. I think I made it to the end of “Harder Better Faster Stronger,” which is 17ish minutes in. Then, I collapsed as “Crescendolls” started, which — considering how energetic that song is — is a little ironic.
To be fair, Discovery is not the greatest running album, as its tempo varies considerably from track to track. Turns out that music is a great way to measure stride frequency: compare to music tempo. Spotify (what I use for music) takes advantage of this with its neat Running functionality, which uses the phone’s accelerometer to extrapolate step rhythm and selects a song with the proper tempo to match it. Usually it comes out to be around 120-140 bpm, which is a reasonable long-distance running tempo. (Fun fact, that range is a consequence of earth’s gravitational acceleration at 9.8 m/s^2. This is also why modern club music is always that tempo; it matches the natural rhythm of humans jumping up and down.) Nonetheless, I don’t use Spotify Running because it uses tons of data and plays songs I don’t really like.
Anyway, I do believe the whole music time-shift phenomenon is strongly correlated with heart rate, which is my next favorite way to judge exertion: putting hand over sternum to feel heart rate and contraction effort, which proxies for stroke volume. Physical exertion correlates well with cardiac output = heart rate * stroke volume, and I really can feel when my heart is beating hard (yay pectus excavatum!). I don’t have a heart monitor or even a watch so it’s not at all accurate, but whatever.
Ah, what about running speed? Since speed = stride length * stride frequency, I need to measure (err… approximate) stride length as well. If I’m on Manhattan city blocks, it’s easy to measure stride length: number of steps per sidewalk concrete segment. It doesn’t work perfectly because there’s a lot of weaving around people involved, but it’s the best I have for now. As an inexperienced runner, I don’t have good proprioception to just feel stride length and frequency (a.k.a. pace), but I’m working on it.
Another great metric for running capability versus intensity: thought content. Some runners say you’re only running hard enough if you can’t think straight. 2 years ago, when I started trying to run, all I could manage was focusing on not collapsing (that was more a consequence of being out of shape than trying too hard). Since then, I’ve progressed to being able to think about pace and distance. Sample: “Should I run to that light pole before stopping?” “Ugh, if I run to 96th St, can I make it back?” “Crap, all these little dogs are passing me right now.” “Nyurrghhhhh” Apparently this is the standard runner’s thought content though; while running, most of the time runners just think about suffering through running.
Recently, I’ve gotten in better shape and I don’t force overly intense runs, so that’s why I can listen to music now. First, it started off with familiar albums (e.g. Discovery), but then I started sampling new releases and thinking the music (these days, I’m pretty caught up with current music). Yesterday, I listened to a podcast. Today, I drafted this blog post in my head. Yay, progress!
A great way to judge personal fitness: running ability. I ran an ambitious and somewhat misguided half marathon last May, which was probably my peak fitness. I lost all sorts of muscle mass when I stopped running this summer in way-too-hot St. Louis, so this August I hit rock bottom, barely able to make 1.3 miles at some crappy pace. Since August, I’ve aggressively ramped up my mileage tenfold in the past three months, which makes me happy, I guess.
This brings up a whole new issue. This morning, I ran during a break before our lecture on common leg injuries like torn ACLs, ruptured menisci, and Achilles’s tendon tears. I’m not so worried about those, but uh… patellofemoral pain syndrome (runner’s knee), iliotibial (IT) band syndrome, and shin splints are all serious concerns for a novice runner like me. I’m being careful about overdoing the running.
On the other hand, people keep on claiming “knee damage” is a valid excuse to never run. I heartily disagree, and so do scientists. I’m not running far enough to worry about chronic damage to my knees leading to osteoarthritis. All the studies I’ve found have only cited increased risk of arthritis in “elite-level long-distance runners,” which in RunnerSpeak means clocking in ~100 miles/week for 40 years straight. Turns out that low- to moderate-level running might even be protective for our knees [1] [2] [3]. Running also improves cardiovascular health, and I’d prefer having stiff knees over developing diabetes and heart attacks and stuff.
Oh, last thing. Running far takes a while, which interferes a bit with scheduling. It also burns a lot of calories, and for someone who’s frail to start with, this means I have to eat way more after runs. Thus, my favorite way to measure energy expenditure: number of meals/snacks required to re-equilibrate hunger. Many of my runs involve ending up at somewhere where I can buy food. Sometimes, I find myself wolfing down a PB&J at 11:30 pm after a 9 pm dessert and a 7:30 pm massive dinner and a 5 pm PB&J, and then I wonder how I got there.
Running, probably.
PS. I also use an actually appropriate run tracking system: Strava GPS tracking. Yay modernity.
PPS. shoutouts to my friends who recently ran marathons, half marathons, and 15k races. You inspire me to keep running.