Using heart rate variability for programming has been de rigueur in endurance athletes for years. Heart Rate Variability (HRV) is based on the body’s autonomic nervous system’s activity, i.e. how hard the sympathetic (fight or flight) and parasympathetic (rest and digest) divisions of the nervous system are working. When there’s greater parasympathetic nervous system activity, the body is said to be more recovered, which can be measured using heart rate data. Specifically, the “R-R interval” is what’s commonly measured, where the R-wave is the big pointy spike you see on EKG tracings and the R-R interval is amount of time between R-waves. For completeness, the R-wave correlates with the contraction of the heart’s ventricles.
Anyway, using HRV for programming not really been evaluated in resistance training. Mike T and I were playing around with this back in ~2014-15, but couldn’t really make heads or tails of HRV trends and subsequent performance. Fast forward a decade, and there’s now some interest in HRV as a potential tool in predicting lifting performance and using it to aid in day-to-day programming decisions. There’s only been one other study on this as far as I know, though I suspect there will be more.
A new study compared the outcomes after 7-weeks of lifting in 21 older women, half of which used HRV to tell them if they were recovered or not. If they weren’t “recovered” per HRV data, they were to delay training for 24-hours. Those in the non-HRV group trained Monday, Wednesday, and Friday regardless.
So, what happened?
Nothing really.
There were no differences in outcomes like muscle size, strength, timed up and go, 6 minute walk, and similar.
This isn’t really surprising to me, as I don’t think “complete recovery” between workouts has a lot of evidence showing it to be beneficial. Instead, I think a better predictor of gainzZz is how much exercise people get in over ~ a month or two. Since they did the same amount of exercise in 7-weeks (a short study really), it’s not surprising they got the same results.
Anyway, take a look at the paper and see what you think!