I love data, especially the ones that help me better understand how my body is performing. I've been using the #WHOOP for close to a year to help me with my training. Now while I enjoy seeing how things like recovery, food, sleep all play a role in how primed my body is the next day, it has been especially interesting to see how it responds when my body is under stress or sick. Here are the top data points you should keep an eye on. For those of us that use the #Oura ring, #Fitbit, #Garmin or #AppleWatch, you can get these metrics as well.
Heart Rate Variability (HRV)
HRV is quite simply defined as the variance in time between heartbeats. For example, if your heart rate is 60 beats per minute, it’s not actually beating once every second. Within that minute there may be 0.7 seconds between two beats, and 1.20 seconds between two others. The greater this variability (higher HRV) is, the more “ready” your body is to execute at a higher level. It can answer your question as to "Should today be a hardcore training day or a yoga day?" So if you are sick or getting sick, you will see your HRV decline.
Resting Heart Rate (RHR)
RHR is the number of times your heart beats when at rest. It is used as an indicator of your cardiovascular health. You can think of this as a real-time selfie of how your heart is looking and working. A rate of 60-100 beats per minute (BPM) is considered "normal". Anything above that range has been linked with higher blood pressure, higher body weight, and lower physical fitness. RHRs lower than the average have been linked with higher fitness levels and lower rates of cardiac events. Now when your body is under stress due to illness or lack of recovery, you will see your RHR increase.
Respiratory Rate (RR)
RR is the amount of breaths you take per minute while at rest. For most healthy adults, RRs can range from 12 to 20. Now this rate doesn't tend to change from day to day BUT when it does, that means something is off. Given our recent COVID environment, this has become a useful metric to keep track of. You will most likely see your RR start to creep up if your body is fighting something.