Heart Rate Variability and Why You Need It

Principle #4 from The Blood Code: Vary your heart rate throughout your exercise routine. 

I grew up in a marathon-running family in the 1970s and early ’80s. Marathons are the archetypal aerobic activity: The runner tries to control his or her target heart rate, keeping it low and steady throughout the run. Those who can keep their heart rate lower have a competitive advantage. Over time, long-distance runners develop a slow resting heart rate, to compensate for the long-sustained increased heart rate from hours of continuous running.

A slow resting heart rate used to be the mark of heart health, but it turns out, this was an unsubstantiated myth. Like we have only so many beats in our lifetime and if you can slow it down, you’ll live longer. Well, the science has matured, and research offers a more complete story. Even back in the 1930s there were signs that “good conditioning” was not about slowing the heart down. During this decade, the Swedish cross-country running team famously improved their performance through an interval training program called fartlek—“speed play” in Swedish. I don’t think a fitness program would succeed today with a name like fartlek; therefore, terms like interval training, cross training, circuit training, and high-intensity training are used to describe the similar practice of “short bursts of more intense activity with interspersed periods of active recovery.”

Convincing research now shows that “heart rate recovery,” a measure of how quickly and how much your heartbeat (pulse) slows back down from a prior effort, is the best mark of your cardiometabolic health.^[i] [ii]

You were born with a healthy heart rate recovery, but, like many things, if you don’t use it, you’ll lose it. Watch kids free-play in the outdoors, and you’ll notice that they exhibit a “go until you can’t, rest until you can” pattern—a very natural and innate exercise style.  We just need to jump off the treadmills and find a workout that really works. And fortunately, it’s never too late to relearn!

An impressive it’s-not-too-late study was done on older people who already had a condition of severe heart disease, and they displayed substantial improvement with their heart rate recovery when they participated in a circuit-type exercise program for at least one hour, three days per week (with supervision), over a twelve-week period. One of the researchers, Leslie Cho, MD, commented on the results of the study, and I couldn’t say it any better myself: Dr. Cho offers, “There’s no medicine that can do that, especially in terms of mortality. . . . If we had a medicine that could make this dramatic an impact, it would be the blockbuster drug of the century.”^[iii]
I’m proud of the metabolic recovery workout I developed with fitness trainer Jeff Eckhouse – it builds strength, improves heart rate variability and speeds heart rate recovery better than any continuous-style aerobic exercise. It’s what I have adopted since backing away from the long distance runs I considered healthy. My resting pulse has sped up, but my HRV numbers are the best ever in my life. It’s a simple method to check your HRV (RMSSD) and a shout out to the folks who developed the app – Elite HRV, it’s simple and packs metrics that used to require $20,000 worth of cardiac rehab equipment. the only other thing you need is a Heart Rate Monitor.  I use this one – It’s the POLAR…get the medium/XXL size for ALL adults. Why do I do it this way?  Maybe it’s  based upon the less-known Vulcan reply, for “peace and long life.”

[i] Dimkpa, U. Post-exercise heart rate recovery: An index of cardiovascular fitness. JEPonline 2009; 12(1):19–22.

[ii] Brunner, E. J., et al. Adrenocortical, autonomic, and inflammatory causes of the metabolic syndrome: Nested case-control study. Circulation 106, no. 21 (2002): doi:10.1161/01.CIR.0000038364.26310.BD.

[iii] Jolly, M., et al. Impact of exercise on heart rate recovery. Circulation. 2011 Oct 4; 124(14):1520–6.