This post is part of Find Your Fit Tech, Lifehacker’s fitness wearables buying guide. I’m asking the tough questions about whether wearables can really improve your health, how to find the right one for you, and how to make the most of the data wearables can offer.
I’ve been wearing an Oura ring for more than three years. I’m also a pretty serious recreational athlete, training not just for fun and for my health, but working toward a goal of getting better and winning competitions in my chosen sport. I find the data my ring gives me useful, but I also use it in exactly the opposite way it wants me to.
I’ve written before about my early experiences with the Oura ring. I’ve also spent some time with the Whoop strap, which provides similar data, as do other gadgets—Garmin has a “body battery,” and Fitbit has a “readiness” score. All of these devices aim to do basically the same thing: tell you how well your body is responding to the stresses of training (and life). Pro athletes and celebrities sport the gadgets, with Oura being the more popular choice among biohacker types, Whoop among jocks, and Garmin among runners. (Personally, I went with the Oura because I find a ring less annoying to wear than a wristband.)
Marketing for fitness wearables makes a big deal of the idea they can tell you when it’s time to skip a workout, or go easy. I get why—it’s a straightforward way of connecting the ideas of working hard and recovering well. Armed with good data, the theory goes, you can make smart decisions about how hard to train and how to support your recovery.
If you’ve never really thought about recovery or training stress before, this might make sense. But it’s actually kind of backwards from how you should be thinking about these factors.
Don’t skip a workout because a score tells you to
To put it simply: Never skip a workout or go easy just because your smart gadget’s recovery score tells you to. (If you feel sick or injured, it might be appropriate to skip—but you’ll know that without a score.)
Why shouldn’t you listen to the app on this? It’s a matter of short-term versus long-term planning—and if you have serious fitness goals, you should definitely be thinking for the long term. A day in the gym is not just a day in the gym; it’s part of a training block that will last weeks or months, and each block has a purpose. Sometimes you’re building a base level of fitness, and sometimes you’re ramping up toward a competition. If you’re a team sport athlete, you’ll have your pre-season, in-season, and off-season training.
If you ran a team, you wouldn’t expect your star player to wake up on game day and say “sorry coach, my watch says I’m only 50% recovered, so I can’t play today.” And as an individual, recreational worker-outer, you are both the player and your own coach, and you deserve to take yourself seriously. It’s one thing to take time off in extreme circumstances (you’re sick, or you have to travel, or your period cramps are really bad). But if you feel fine, there’s no good reason to skip or half-ass a workout because of a score on an app.
Whoop actually ran a study to test this, and maybe it’s bad form to say “I told you so,” but I told you so. The writeup talks so much about how people improved overall that it manages to bury the primary finding in a table deep in the article: Runners who adapted their training based on their recovery score had basically the same improvements in their time as runners who stuck to a cookie-cutter program. The runners on the adaptive plan ended up running less often, which Whoop spins as the runners seeing similar gains with less training. I’m skeptical of that assumption. Wouldn’t less training over time result in less progress in the long term? It’s impossible to know, since the study ended after eight weeks.
Here’s how I see it: Short term decisions, like skipping or altering today’s workout, are for unforeseen circumstances that need a short-term solution. But “I skip my workout if my readiness score is lower than X” is a series of short-term decisions with long-term consequences. If you have less-than-stellar scores on a regular basis—as you probably should if you’re working hard—you’ll miss out on a significant amount of training, and you won’t be executing the training block as planned.
Your issue should instead be dealt with via long-term planning. Either your training program is too hard and it isn’t appropriate for you, or your training program is one you’re expected to do while you’re a bit fatigued, and you’re just chickening out instead of doing the work. In either case, you need to fix something (your training program, your recovery, your attitude) that can’t be fixed by skipping a single workout.
Training stress is part of training
Let’s return to that idea I mentioned above: It can be a good thing to have low “recovery” or “readiness” scores. If you’re only thinking in the short term, that probably seems weird. Wouldn’t you want to be at the top of your game all day, every day?
Here’s the thing: Exercise is work. It stresses your body. Your body responds to that stress by getting stronger. Without stress, you would never improve. And as a result of that stress, you get fatigued. If you’re a runner, it’s normal to feel pooped after your Saturday long run, no matter what you do recovery-wise later that night. On Sunday you’ll probably want to take it easy. That doesn’t mean that the long run was bad for you, or that you did anything wrong. It just means that you did a hard thing and your body is going through the process of getting stronger.
Here’s where smart programming differs from making a knee-jerk decision based on recovery scores: Your gadget will probably tell you to take it easy on Sunday if you just ran a long run on Saturday. Should you? It depends who you are and what your goals are. A beginner running program will give you a rest day on Sunday, because you’ve done enough for the week. An intermediate program might give you an easy “recovery” run instead, to help you get more miles in without pushing you too hard. And if you’re an ultramarathoner, you might actually get more mileage for Sunday, to give you practice with running on tired legs. In that kind of training program, fatigue isn’t a necessary evil, but a valuable training tool.
Your recovery gadget doesn’t know what kind of program you’re following. It just sees that your metrics are indicating you’re tired. What to do about that depends on how you’d like to train. Just like ChatGPT, fitness wearables are not smart enough to be your coach.
Compare your recovery scores to what you expect from your current phase of training
If you only ever train when you’re feeling 100%, you’ll miss a lot of training days. To be fair, the algorithms in these recovery gadgets understand this, at least somewhat. You’ll get an “optimal” or “green” score on your best days, and a “good” or “yellow” score on days when you’d still expect to be able to put in a solid performance. But that doesn’t mean you should stay home just because you’re fatigued or because you expect training to feel hard. It makes more sense to compare your recoveries to the kinds of scores you should expect for your current stage of training.
For example, if you’re in a training week that’s supposed to be hard, and you’re getting optimal recoveries every day, that could be a sign your training is too easy. If you’re supposed to be shedding fatigue as you taper for a competition, yet your recoveries are consistently in the toilet, it could be time to revisit your plan and make sure you’re actually reducing training volume enough to allow you to recover.
The recovery data that’s actually useful
So far I’ve been telling you what to ignore. So let me tell you what data from my Oura I actually use.
First, I ignore the readiness and sleep scores themselves, and look at the raw data. Each of those scores is determined by an algorithm that considers many different variables. Some of those variables I care about, and some I don’t. For example, I find that a long, slow bike ride on my rest day is better for me than sitting on the couch all day, but that means I’m not following Oura’s idea of what a rest day should be, and so it disapproves and lowers my score.
Heart rate
I find my heart rate variability, or HRV, to be the most useful number. I used to pay more attention to my resting heart rate (RHR), but after tracking these numbers in a spreadsheet for a bit and comparing them to how I actually felt and how I performed in the gym, I now believe the HRV is the better gauge of how my recovery is going.
Resting heart rate is still useful for pointing out bigger problems, like if I got too little sleep on a given night, or if I’ve been sick and haven’t fully recovered. (Some people find that Oura tells them when they’re about to get sick, but not me; I get great recoveries my first few days of a cold, even though I’m feeling awful.)
If my HRV is high most days, I’m probably recovering well enough to support my training. If it’s medium, that usually means I’m in a tough training block and need to pay extra attention to getting enough sleep and taking care of my body and my mental health. And if I have more than one or two days in a month with a low HRV and high RHR, that’s a sign that I’m either struggling with my training intensity or that I’m staying up late and/or drinking more than I should.
Time in bed (but not sleep stages)
I don’t trust my rings data on sleep stages at all. In my first review of Oura, I wrote that it under-counts my minutes of REM sleep. Oura has since released an updated algorithm that seems to be more accurate, at least for me. I still wouldn’t trust any consumer wearable to be truly accurate about sleep stages, though.
But I do appreciate seeing my total time in bed. I don’t make training decisions based on the amount of sleep I got, but if I notice I’m short a few nights in a row, I’ll make sure to get to bed early the next couple days. I could make that decision just based on how tired I feel, but I find that having a solid number helps me drag my night-owl ass to bed even when I don’t want to go.
How to actually use your recovery data
The most important thing to know when you’re tracking data is how you’re going to use it. I reject the idea that I should use recovery data to make day-to-day decisions about how to train. So how do I use it?
For a reality check on sleep time
Sleep is one of the biggest levers we can pull when it comes to having more energy in the gym or just in life in general. Wanting to get more sleep is not the same as actually getting more sleep, so it’s important that I make sure my efforts are paying off. The “time in bed” metric is the most useful one here.
To adjust training intensity
I will sometimes make decisions about my training in that more long term sense—week to week, not day to day. This doesn’t apply if I’m following a very specific program from my coach (although I’ll discuss any problems with him, if necessary). But there are blocks of time where I have the freedom to decide how hard I’m training.
If training is hard, but I’m feeling good, and my recovery numbers are good, that tells me I have room to bump up the intensity a little if I want.
To pay more attention to recovery
If my recovery numbers are dropping, that’s a sign that I need to pay more attention to the things I’m doing outside of the gym. (Dropping training intensity could be on the table, but usually isn’t necessary.)
The first thing I’ll do is get more sleep. If I’ve been waking up early for morning workouts, I can squeeze in a little more sleep by scheduling that workout for later in the day. I’ll also do my best to get to sleep earlier—easier said than done—and I might consider using melatonin and revisiting my sleep hygiene habits.
Alongside my sleep schedule, I might work on other areas of recovery. Eating more and doing more low-intensity cardio both tend to help my body handle training stress. (I swear, cardio is a cheat code for work capacity.) These factors don’t always lead to improved recovery numbers, but they seem to help me feel better and do more work.
By using my recovery data this way, I’m still in control of my training, and still in touch with how my body responds to that training. The little bundle of sensors I slip on my finger isn’t my coach or my boss or my mom. I consider it for what it is: one of many tools that help me in my training.
