Since getting into standup paddleboard racing I've started paying attention to physiological aspects of fitness, like Heart Rate (HR). I'm no expert in HR, but here's what I've learned from the Internets:
1. HR is a measure of how many times your heart beats in a given time period. It's usually expressed as bpm: beats per minute.
2. Your heart beats slower when you are resting, and faster when you are exercising.
3. There is a big difference between your "resting HR" and your "maximum HR".
4. Exercise scientists divide the range between resting HR and maximum HR into about 5 "zones" of exercise intensity.
6. Each person's resting HR, maximum HR, and zones are unique to that person, but there are some trends in HR based on age and fitness level.
7. Resting HR is usually 50-80 bpm, but it tends to be lower in more fit people and higher in out-of-shape people.
8. Maximum HR tends to be >200 bpm for kids, and decreases steadily with age. Fitness training doesn't increase your Max HR, but it might help maintain it as you age.
9. There's a "rule of thumb" for calculating your maximum HR. It's: Max HR = 220 - Age. There's also a more precise formula: Max HR = 211 - (0.64 x Age). (Nes et al. 2012)
10. Due to natural genetic variability, it's common for your true Max HR to be up to 20 bpm higher or lower than the Max HR predicted by the formula.
11. To figure out your true Max HR you need to do a "stress test," which involves exercising, increasing the intensity to 100%, and measuring your HR at that point. Fun!
There are lots of charts and guides figuring out your heart rate zones and training, but I wanted to make one that could be easily customized for an individual. So, I came up with the excel version below. Try it out and let me know what you think.