Sports Science Update: Heart Rate Recovery Indicates Fitness, Fatigue

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A new study suggests monitoring your heart rate recovery day to day may be worthwhile.

Heart rate recovery refers to how long it takes for one’s heart rate to return to resting level after completion of exercise. Heart rate recovery is faster in aerobically fit individuals than in less fit persons. This much has been known for many years. What has not been known is whether short-term changes in HRR within fit individuals can predict performance – that is, whether such changes are useful indicators of changes in fitness and/or fatigue levels in trained endurance athletes. A new study from the University of Cape Town, South Africa, suggests that it may well be.

Published in the Scandinavian Journal of Medicine & Science in Sports, this study looked at changes in heart rate recovery in competitive cyclists subjected to four weeks of high-intensity interval training. Each of the 14 subjects completed a 40K simulated time trial on an indoor trainer before and after this four-week period. Some cyclists showed a trend toward improved heart rate recovery while others went backwards. Also, some of the subjects performed better in the second time trial while others performed worse. The authors of the study crunched the numbers to determine if those who showed improvement in heart rate recovery also tended to perform better in the second time trial, and if the obverse was also true. And sure enough, they found a statistical correlation.

They concluded, “These findings suggest that HRR has the potential to monitor changes in endurance performance and contribute to a more accurate prescription of training load in well-trained and elite cyclists.”

To measure your heart rate recovery, wear a heart rate monitor before, during and after workouts. Note your resting pulse before the workout begins. At the end of your workout, time how long it takes for your heart rate to return to that resting level. Be sure to end each workout at the same heart rate, for example by cooling down until your heart rate gets down to 125 bpm, then stopping and beginning the HRR measurement process.