Resting heart rate predicts fitness level

the study covered in this summary has been published in as a preprint and has not yet been peer reviewed.

Key points to remember

  • The inverse relationship between resting heart rate and maximal oxygen uptake is directly correlated with fitness and adiposity.

  • Resting heart rate is a biomarker of physical fitness and, therefore, a predictor of cardiorespiratory health.

why it matters

  • An increase in resting heart rate has been associated with an increase in all-cause mortality from chronic diseases, such as type 2 diabetes and cancer.

  • Resting heart rate can be used as an inexpensive and non-invasive way to assess cardiovascular disease risk and the effectiveness of physical activity interventions.

study design

  • The population-based study cohort consisted of 5722 women and 5143 men aged 29 to 65 years.

  • Resting heart rate and fitness were assessed at baseline and a median of 6 years later.

  • Resting heart rate was measured with two standard electrocardiogram electrodes while the patient was sitting, lying, and asleep.

  • A sensor worn for 6 days and nights was used to monitor heart rate during sleep.

  • To measure fitness, participants walked, incline walked, and ran on a treadmill.

  • Physical activity was measured over a 6-day period using a combined heart rate and motion sensor, and this data was correlated with data collected during treadmill exercise.

  • Other parameters assessed, and their possible influence, included body mass index, alcohol consumption, smoking status, ethnicity, and body composition (assessed by dual-energy X-ray absorptiometry).

Principle results

  • The average resting heart rate while seated was 67 beats per minute, supine 64 beats per minute, and 57 beats per minute while sleeping.

  • A one beat per minute increase in supine heart rate was associated with a decrease in fitness of 0.23 mL/min per kg.


  • Fitness was extrapolated from heart rate response to submaximal exercise instead of a direct measurement of maximal oxygen uptake.

  • Participants taking beta-blockers were excluded from the study because fitness estimated from heart rate response to submaximal exercise was found to be unreliable in these individuals.

  • Because the study did not include children or adolescents, the researchers are unable to report on the relationship between resting heart rate and cardiorespiratory health in this age group.


  • The authors were supported by the UK Medical Research Council.

  • No author declares competing interests or financial support from organizations that have had an interest in their submitted work in the previous 3 years.

This is a summary of a preprint research study, Resting Heart Rate Is a Biomarker of Cardiorespiratory Fitness: The Fenland Study, authored by Tomas Gonzales and colleagues from the University of Cambridge, UK, published on SSRN and provided by Medscape. This study has not yet been peer reviewed. The full text of the study is available at

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