Better Living Through Data

March 13, 2025 8:59 PM

How do you use your smartwatch, fitness band, and/or Strava or similar app to improve your life? I track seemingly vast amounts of data about myself through an iphone, Garmin Vivoactive watch, Polar heart rate monitor, Wahoo SYSTM using a KICKR bike trainer, and Wahoo bike computer. But, I don’t really do anything with it other than looking at bike routes or distances. How have you used these tools to improve your performance in your sport, general health, sleep, mental health, or in some other way? Any specific advice for the gear I’m using would be helpful, too.
posted by fieldtrip to Health & Fitness (9 answers total)

Well, I know multiple people whose Fitbit finally convinced them they had to cut back on alcohol. They could so clearly see how crummy their sleep was when they drank even a glass or two in the evening that the habit lost its appeal.

In my day to day, I mostly use it to motivate me - I like that it counts my active minutes and gives me a little bit of shit if I'm not exercising regularly. I'm not someone who has any intrinsic motivation to exercise and it helps to feel like the Fitbit is "noticing" and "giving me credit" for my efforts. If this kind of attention was coming from a trainer or coach I think I'd find it condescending or feel cynical about it but somehow the same feedback coming from a wristwatch with delusions of grandeur hits just right. I don't know why I'm like this but it appears to be working so I'm not going to let myself think too hard about it.
posted by potrzebie at 10:41 PM on March 13 [3 favorites]

I used the ECG function on my Apple Watch to pick up what turned out to be skipped beats that I’ve been having a lot lately. Went to the ER when I was having them for an hour straight — their EKG was normal (thankfully no afib), but the doc saw my watch and offered to read the strips from my phone. That feature alone makes it worth it. (And it does pick up afib! But not heart attacks just fyi.)

The AW also tracks low and high heart rate and VO2 max, also useful for picking up warning signs and probably as proxies for improved cardiovascular performance (eg improved VO2 max and lower resting HR).

I keep loose track of the sleep data. That way, when I’m having a bad day I know why that is and remember to tighten my sleep hygiene. 10/10 times I’m having a bad day, eg I feel slow or low in mood, I got < 6 hours of sleep. Good days are almost always correlated with getting > 7 hours.
posted by cotton dress sock at 2:13 AM on March 14

Post-Covid exercise was spiking my heart rate oddly and then my my afib warning went off so I stopped procrastinating on going to see my doctor and ended up fast-tracked to cardiology where I learned I was indeed having atrial fibrillations and other arrhythmias. (FWIW I ran a 10k the day before I got Covid.) After 6 months on a beta blocker I was able to get back to normal and now I use it to track my cardio and keep an eye on my resting heart rate.

I do track sleep but as a perimenopausal woman it’s mostly depressing. I have been able to use the data to convince others to stop encouraging the dog to wake me up on Sundays instead of them. :)

I’m not really super competitive about my exercise stats though so other than kind of minutes and sometimes distance I don’t use all the things to optimize.
posted by warriorqueen at 4:17 AM on March 14 [1 favorite]

I have inflammatory arthritis, but I'm also an enthusiastic runner with a busy life, so it's really easy for me to overdo it without meaning to. Of all the indicators I've tried, overnight heart rate variability has turned out to be the thing for me to watch to know if it's a day to exercise or a day to take it easier (or a day to fucking collapse). Last year I upgraded from a Fitbit to a Garmin, and I'm finding the stress indicator, which is also based on HRV, really helpful as well. Because of the constant stress of inflammation, I rarely get the "Easy Day" message, but I try to remember to notice during the day what my stress levels have been like and when I have a free moment do some active effort to bring my HRV down.

Also, I just love browsing through all the Garmin run data even though it's entirely too much data. It's a hobby.
posted by hydropsyche at 4:32 AM on March 14

Well, I know multiple people whose Fitbit finally convinced them they had to cut back on alcohol. They could so clearly see how crummy their sleep was when they drank even a glass or two in the evening that the habit lost its appeal.

Same thing among Whoop users I know.

I realized years ago that I was never going to start getting more sleep, so I needed to figure out how to get better sleep. My Whoop data led me to make changes to my caffeine consumption habits (done by 3pm), sleep time and wake time (try to keep both consistent, unless I wake up earlier naturally), and exercise and strain (avoiding evening workouts).

Tracking weight and food consumption are both helpful for weight loss.

I only actively monitor my heart rate while I'm on my Peloton, but it's useful for increasing/decreasing intensity based on my ride and what I'm trying to achieve.
posted by NotMyselfRightNow at 6:09 AM on March 14

I've worn fitness trackers for over a decade and really appreciate the info I get. A few ways they've changed my behavior listed below. I should say that Peter Attia's book Outlive also colors these choices, so a few shoutouts along the way.

I have never been a heavy drinker, but my Garmin fitness tracker made it clear that even a little alcohol consumption in the evening (1-2 glasses of wine) drops my "body battery" significantly the next morning. Near as I can tell, "body battery" is derived from heart rate variability, aka the ability for the heart to respond to changes in activity level throughout the day. I would not have expected that very light drinking would affect my heart so immediately and so strongly, and this definitely changed my perspective about casual drinking. I still do it occasionally, but very occasionally, and don't think of it as harmless any more.

Sleep tracking quantified that my sleep used to be really poor and short. Outlive goes into the importance of sleep at some length and this put my data into perspective. So, I embarked on an intentional plan to improve it. Nothing revolutionary--dramatically less caffeine, stop drinking coffee before noon, set bedtime and wake time. Also acknowledging that every night I will wake in the wee hours for an hour or so, but this doesn't mean I can get up for the day. Sometimes I will become sleepy again and drift off unaided, sometimes I need a single pull on a "sleepy weed" vape to help me get there. (I don't otherwise partake. Granddaddy Purple is a friend of mine.) It's still a rare day that I get a full eight hours but I'm doing far better than my prior stint of four to five per night, and I still appreciate the quantitative info along the way.

I also track exercise and appreciate the "intensity minutes" tallies from my watch. I'm a fat middle aged lady, have been a fat person since forever, and am well aware of every dire health warning related to this. I have also exercised regularly for years and years, and want to cultivate my strength and cardiovascular health for as long as possible (Outlive again). Meeting and oftentimes greatly exceeding the 150 minutes of moderate exercise/75 minutes of vigorous each week is important to me and I appreciate the record/proof that I have done so, or if I am falling short, need to move more to reach that goal.

Finally, I have appreciated resting heart rate data over the years and have gotten a few interesting insights about how my body behaves along the way from this info. I also am proud (see preceding paragraph) that my RHR is in the mid-fifties. To the casual viewer I don't look particularly fit but my heart acts like it is and I guard that carefully.

I guess while I'm at it I should also credit my Withings smart scale and its app. I have really good records of my weight over the past few years. At my doc's recommendation I have been taking Wegovy for the past year. She and I ramped up my dosage quite conservatively and slowly and I'm at the lower "full dose", specifically because I would like to minimize muscle loss. As a result my weight is dropping also pretty slowly, like two or so lbs per month. The Withings app computes monthly averages of weight and I've found this is a less crazymaking metric for me to focus on than variations in my weight day to day. The scale also purports to measure body composition through impedance. These metrics are generally wildly inaccurate, so I don't believe the absolute numbers it claims, but it's encouraging to see the fat loss trend over time.
posted by Sublimity at 6:55 AM on March 14

I use my AppleWatch for a couple difference things -

- Looking at sleep performance has helped me realize what a big effect sugar has on my sleep quality, and since cutting back on sugary treats, I am now getting 7-8 hours nightly on a consistent basis. FYI, I am a postmenopausal woman.

- I track Active Energy daily when dieting as a way to guarantee that I am remaining active enough to benefit from the reduced calories I am focused on. I like this better than measuring steps since I use machines at the gym, swim, and do other things that are not easily measured when counting steps.

- Recently after a medical issue, it was regular pulse tracking that made me realize something was wrong with my heart and was the thing that got me in front of a cardiologist.

- I use the Workout function to determine how long my workouts need to be. If I am at the gym and haven't hit my Active Energy goal, I stay a few minutes longer even if I have completed all the elements of my normal gym routine. It's also helpful for remembering which days I worked out.
posted by eleslie at 6:57 AM on March 14

It depends on what your goals are, but if you've got all that stuff, it seems safe to assume you want to become a stronger cyclist. If that is the case, you should really acquaint yourself with the principles of structured training. There's a book, "Training and Racing with a Power Meter," by Andrew Coggan, that is sort of the ur-text of structured training, but there's enough information on the Internet that you can get away without reading it. It does take a certain commitment to learning this stuff, but it's really changed my approach, and made me a measurably stronger cyclist.

I track all my workouts in Training Peaks, and while I could get more out of it, it is useful for showing whether I am progressing (ramp rate > 0) or overtraining (TSB < -20). I am not being methodical about planning workouts in advance in Training Peaks right now, but I have used it for that too. There are other apps and services that do more or less the same thing, eg Intervals.icu.
posted by adamrice at 8:16 AM on March 14

On my easy runs, I keep an eye on my heart rate. Although I can generally tell how hard I'm working based on feel, if I'm worn down sometimes I feel like I'm running slowly but my heart is 30 bpm higher than it should be, so I slow down.

I've always known that sleep matters for recovery, but tracking it really made it clear how strong that relationship is, so now I actually go to sleep on time. HAHAHHAHAHHA. Of course not. I just hate myself more in the morning for having stayed up too late.
posted by Mr.Know-it-some at 8:23 AM on March 14 [1 favorite]