Using Your Resting Heart Rate as a Guide
Given the number of folks coming down with a bug or the flu lately, I thought I would take this opportunity to get into the basic rules of how to tell if you're ready for a workout.
Let me start by saying that having a good idea of your normal resting heart rate is a good idea. I’ve known folks that check it first thing in the morning, every morning, before even getting out of bed. All kinds of things can affect your resting heart rate. Obviously the more fit and healthy we are, the (generally) lower our heart rate is going to be. But knowing how far off from your average you are on a given day is the important part. That resting heart rate is a pretty reliable indicator of your readiness to put in a hard effort. If you’re several beats above your “normal” resting heart rate, then your body probably isn’t ready to really put in a solid quality workout that will help you become a better runner.
So how do we figure out what our resting heart rate is? And what is “normal” for each of us? To determine your heart rate at any given time, you can find your pulse in your wrist or neck using the first two fingers, not your thumb. You can actually get a little bit of interference from the blood pulsing through your thumb if you try to use it instead of your fingers. If you have a really strong heartbeat you can also just put your hand on your chest, but the wrist or neck is normally ideal. Once you’ve found your pulse, count the number of times you feel it for 30 seconds, and multiply by two. Technically counting it for a whole minute is more accurate, but the real world difference isn’t enough to really matter for what we’re looking at it for. The other big important part is to make sure you haven’t had a super strong cup of coffee yet, as the caffeine will bump your heart rate up a notch or two.
As far as what’s “normal” for you, that’s going to vary from person to person. I’ve had client that hang out in the 60’s or higher, but I’ve also had folks that routinely cruise at about 45 beats per minute. You will get a feel for what’s “normal” for you if you regularly track your resting heart rate, developing a baseline to operate from. You may find though that your resting heart rate is lower than “normal” on days when you wake up super relaxed and recharged. If this happens to you it may indicate that you’re carrying around a decent amount of background stress. This may be something to look at addressing to improve your response to training. We’ll cover that in another article though.
Resting heart rate is useful for us as runners to get a gauge on whether or not we’re recovered from the last hard workout we did. And this is because the higher the stress load on our bodies, whether it is from training, work, or life, the higher our heart rate is going to be. Our bodies don’t really have an easy time distinguishing between different types of stress, we just know that our cortisol levels are through the roof and inflammation is up. When we have a hard workout, it’s stressful on our bodies, and we get this same stress response. When the body has recovered from the damage we inflicted on it in training, the stress response goes away, and this is reflected in our resting heart rate.
But our workouts aren’t the only thing stressing our bodies. That baseline stress level can creep up from a wide variety of factors. Sometimes the stuff is hitting the fan at work. The holidays are notorious for stressing people out. And we can get sick. Some of these things we can’t do anything about, but it is important to recognize their impact on our ability to recover from workouts, and be in a position to put in a hard effort. My general rule of thumb is that if my resting heart rate is more than 5 or 8 beats above my normal, I’m not even going to think about doing a long or hard run. I’m still going to get some easy miles in, or maybe a recovery workout, but I’m also not afraid to take a day off if that heart rate is high enough.
And this brings me to the last and most important part for today: being sick is a workout. Most of us don’t think of it that way, but from a physiological perspective, our bodies are working at a harder than normal effort for 24 hours a day while we are sick. It’s important to remember that if our bodies are working harder than normal, even if it’s not as hard as gut-busting 400 meter repeats, being sick is a long duration workout. Most reasonable folks I know wouldn’t expect their bodies to be able to get anything out of a long or hard effort after waking up from a several day long effort, no matter how slowly they were going the whole time. Just like we have to respect the distance of our long runs and races when recovering, we have to respect the work our bodies have done when we were sick.
Normally it takes a day or two to fully recover from being sick. Even after we start feeling good, our heart rate is normally still elevated for another day to two, indicating that we’re actually recovering from the effort of fighting off the sickness. So be sure to use that resting heart rate as a guide. You may feel fine, but your body isn’t ready to get ground into dog meat quite yet. It’s the same as trying to do hard workouts and long runs multiple days in a row. You can do it. But you’ll be in better shape a month from now if you fully recover and hit that workout in a couple of days than if you try to force your body to do the hard workouts before you’re recovered.
So don’t get greedy as we head into the spring racing season. Train smarter, not harder.
Disclaimer: There are a whole host of dietary and medical issues that can influence your heart rate and resting heart rate. Diagnosing and treating these issues is beyond my scope of practice, but I might be able to point you in the right direction if you have specific questions.