Printer icon

Knowledge is Power: How to Measure your Stress Levels

Traffic noise

One of the tricky things about stress is how hard it is to really measure. The same event could have two totally different effects on different people: maybe you have no problem at all driving on the freeway but your friend absolutely hates it and spends the whole time stressed to the max. For an amateur gym rat, squatting 200 pounds might be a big physiological stress, but for a trained powerlifter, 200 pounds not be a significant physical stress at all.

Just having stressful events in your life isn’t necessarily a problem. Stress is just something that challenges your physical or mental stability, and it’s totally possible to experience stress, recover from it, get your groove back, and keep going. Sometimes it even makes you stronger. But if the amount of stress you’re under exceeds your ability to recover, and you’re just accumulating more and more damage without being able to repair it, then there’s a problem.

But how do you know when that’s happening? It’s hard to really get an objective idea of physical + mental stress – some people are really good at ignoring it! Measuring stress can help give you a reality check about your own stress burden, and it can also make the problem of stress management a little less overwhelming. So here are two ways you can get an objective, accurate look at overall stress: blood testing and heart rate variability testing.

Blood Tests

If you have access to a sympathetic doctor, and if you have money to pay for the tests, there are a bunch of blood tests that measure stress hormones and inflammation. No one blood test is perfect, but if you have elevated markers for a bunch of things, it might be worth checking out.

Some common blood tests include…

If you take one of these tests, the doctor giving you the test will be able to explain what all those things mean. But the downside to blood tests is that you can’t really do them regularly. Even if you could afford it or your insurance covers it, who wants to go to the doctor and wait in line and get blood drawn on a regular basis? For most of us, these tests are an occasional snapshot of how we’re doing on that particular day, not a long-term look at the big picture.

That’s a problem because the exact moment when you get the blood test might not be representative of your overall stress levels. Most of these markers are very sensitive to acute variations in stress, but that might not be accurate in the long run. For example, a hard workout will increase inflammation markers immediately after the workout, but regular exercise decreases inflammation in the long run. So if you go get blood drawn just after a run, you’ll think you’ve got crazy inflammation problems, but actually you don’t: it’s just a temporary and normal response to a workout.

What if you’re having a particularly bad or stressful day on the day of the test? What if just being in the hospital and having a needle stuck in your arm stresses you out? There are all kinds of reasons a one-off test might be inaccurate.

The ideal would be to have a cheap, non-invasive test that you can do every day at home, so you can get a lot of data and see the big picture without spending your whole life watching doctors stick needles in your arm. Enter…

Heart Rate Variability Testing

Put your hand on your heart and feel the beats. It probably feels like it’s going at exactly the same pace – the amount of time between heartbeats is basically even. Of course, you could make it go up (get up and crank out a bunch of jumping jacks and then check again), but when you’re just sitting quietly, it feels like your heart is basically pumping at a steady pace. But actually, there are tiny variations in the length of time between your heartbeats. It’s not exactly the same amount of time from one beat to the next. This is called heart rate variability.

These changes aren’t obvious, but they are important – changes in heart rate variability are a good measurement of overall stress load. Athletes already use it as a measurement of overtraining (physical over-stressing), but it works just as well for psychological stress like daily worry and exam stress in students. And in news that shouldn’t be surprising at all, abnormalities in heart rate variability are associated with everything from cardiovascular disease to eating disorders to diabetes to  depression – and probably most other diseases where stress is a factor.

Heart rate variability is a good measurement of overall stress because it reflects the activity of the “fight or flight” response, technically called the sympathetic nervous system. The sympathetic nervous system is activated when you’re under any kind of physical or psychological stress: running from a crazy dog that got off the leash, worrying yourself sick about an upcoming deadline, dealing with a screaming toddler – it’s all sympathetic country. And heart rate variability is basically a measurement of how much that “fight or flight” response is being activated:


Heart rate variability measures all of the above, plus sleep deprivation, exercise stress, stress caused by a lousy diet…

You can monitor your own heart rate variability to get a good ballpark idea of how much stress you’re under. You’ll need a heart rate monitor with a connection to your smartphone, and an HRV app (there are free options for Android and iOS). There are also some companies that sell a complete package of equipment for measuring HRV, which is pricier but convenient because you get all of it in one package. Here are reviews for two of them, the BioForce and the iThlete.

Heart rate variability testing is handy, because it can measure small fluctuations in stress without losing track of the big picture.

Knowledge is Power

If you know your own stress levels, you can keep plugging right along (if you’re doing fine), or adjust your routine as necessary (if you’re not). You can immediately tell when you’re taking on too much, and measuring overall stress lets you play around with tradeoffs, like cutting back on one workout to let yourself fully recover from another. Real people in the real world aren’t always the best at recognizing when we’re under stress – a tool like HRV monitoring can be a nice, objective reality check and a way to stay in touch with your own body.

This kind of really objective, numbers-based data might also be helpful if you’re struggling to know where to even start with stress. Just see how your body is actually doing – what kinds of things are actually an issue for you? Stress can be a really vague problem: it’s everywhere, but it’s hard to pin down exactly and even harder to “manage.” Start by putting some numbers and a graph on it, and then maybe experiment with things like meditation to see if they actually help you.