5 Heart Rate Metrics You Should Know
[Portions of this post appeared in an article written for Under Armour in 2019. They have since left the cycling business:(. Some links may go to an archived version of their now-defunct cycling blog.]
I’d love to see more of my riders up the ante. To ride ‘en plein air’, as the French impressionists would say, and ride, hike, or run outdoors. Understanding heart rate helps in the transition from indoor exercise to outdoor excursions.
Heart rate is a measure of your body’s reaction to work, not the actual work being done. Training with heart rate holds you accountable throughout your entire workout — not just during the sprints.
Research purports cyclists with low watts (50) and cadence higher than 110 spend up to 60% of their energy just spinning their legs., leaving only 40% for overcoming resistance. That’s akin to doing jumping jacks with just your legs and calling it a complete workout.
For riders who have three pedaling modalities — “hard, harder, hardest” — paying attention to heart rate data provides a new lens to gauge intensity. Instead of pedaling toward breathlessness, use a heart rate monitor (or fitness tracker) to gain specific feedback about your performance.
Here are a few heart rate metrics to be aware of:
1 - RESTING HEART RATE
This represents the number of heartbeats per minute while at rest. Try taking it when you wake up and before getting out of bed. The resting heart rate, generally between 60 and 80, provides a glimpse into the health of your heart. Lower numbers generally reflect more efficient heart function or athletic fitness, while higher numbers may signal larger health problems. For best results, take the average of multiple tests.
2 - MAXIMUM ACHIEVABLE HEART RATE (MAX HR)
Max heart rate is the highest number of heartbeats your body can sustain in one minute. Max HR is mainly genetic, you can’t train it, it just is.
The old formula to find max HR (220 minus age) is less accurate than a new gender-specific means of measurement — 214 minus (0.8 x age) for men and 209 minus (0.9 x age) for women — though other methods exist.
3 - RECOVERY HEART RATE (RHR)
This is one of the best indicators of cardiac health. RHR measures how quickly your heart rate normalizes after an exhaustive (>75% of max HR) effort. Take your heart rate 1–3 minutes following an intense effort. The healthy and fit heart sees a faster decline in beats per minute. A decrease between 15–25 heartbeats per minute is the normal range.
4 - HEART RATE VARIABILITY (HRV)
Heart rate variability is an emerging metric that measures levels of fatigue and physical fitness. HRV captures the elapsed time between successive heartbeats (known as the inter-beat or R-R interval). This variability provides insight into your body’s ability to handle physical duress and/or need for recovery. Try to measure it the same way each time to get a base level since everybody is different. The Oura Ring or Whoop band are the leaders in HRV-specific devices.
5 - HEART RATE RESERVE (HRR)
Heart rate reserve is the difference between your max HR and resting HR. HRR allows you to gauge effort as a percentage of your max HR. Managing your effort across HRR is essential for endurance efforts, like climbs and time trials. Many fitness trackers employ heart rate zones to stratify levels of intensity. Enhance your mind/body connection as you learn to associate duration with intensity.