Measuring Energy Expenditure and Heart Rate during Maximum Aerobic Testing with the Apple Watch Series 7 Original Research

Main Article Content

Flavia Rusterholz
Andrew Rodriguez
Victoria Ortiz
Corey Peacock


Aerobic capacity, Caloric Expenditure, Heart Rate


Introduction: Wrist-worn devices such as the Apple Watch have emerged as technology for tracking physical activity. The aim of this research study is to analyze the Apple Watch Series 7 (AW7) with measurements of the maximum heart rate (MHR) and maximum energy expenditure (MEE) during a maximal aerobic capacity test on the treadmill. AW7 measurements will be compared to the Polar Heart Rate Monitor (Polar) and the PARVO Metabolic Cart (PARVO).

Methods:  22 healthy and active subjects (mean ± SD: age 23.8 ± 4.0 years; BMI 23.0 ± 5.9 kg/m2) volunteered for the study. The subjects confirmed their activity, health status, and were measured for body composition and aerobic capacity.

Results: No significant difference was found in MEE between PARVO (109.6 ± 41.7 kcal) and AW7 (98.7 ± 24.3 kcal) conditions; t(21)=1.5, p = 0.153. In addition, there was no significant difference in MHR between PARVO (186.2 ± 16.2 BPM) and AW7 (189.3 ± 8.5 BPM) conditions; t(21)=-0.9, p = 0.379.

Conclusions: The main findings of this study show that the MEE as well as the MHR between the AW7 compared to the PARVO are not different.

Abstract 331 | PDF Downloads 216


1. Tien NH DN, Chi DT. Product policy in international marketing comparative analysis between Samsung and Apple. IJAFR. 2019;1(2):129-133.
2. Massoomi MR HE. Increasing and Evolving Role of Smart Devices in Modern Medicine. Eur Cardiol. 2019;14(3)doi:10.15420/ecr.2019.02
3. Lui GY, Loughnane D, Polley C, Jayarathna T, Breen PP. The Apple Watch for Monitoring Mental Health–Related Physiological Symptoms: Literature Review. JMIR Mental Health. 2022;9(9):e37354.
4. Jo A, Coronel BD, Coakes CE, Mainous AG, 3rd. Is There a Benefit to Patients Using Wearable Devices Such as Fitbit or Health Apps on Mobiles? A Systematic Review. Am J Med. Dec 2019;132(12):1394-1400.e1. doi:10.1016/j.amjmed.2019.06.018
5. Apple. Empowering people to live a healthier day. 2022.
6. Falter M, Budts W, Goetschalckx K, Cornelissen V, Buys R. Accuracy of Apple Watch Measurements for Heart Rate and Energy Expenditure in Patients With Cardiovascular Disease: Cross-Sectional Study. JMIR Mhealth Uhealth. Mar 19 2019;7(3):e11889. doi:10.2196/11889
7. Shcherbina A, Mattsson CM, Waggott D, et al. Accuracy in Wrist-Worn, Sensor-Based Measurements of Heart Rate and Energy Expenditure in a Diverse Cohort. J Pers Med. May 24 2017;7(2)doi:10.3390/jpm7020003
8. Duking P, Giessing L, Frenkel MO, Koehler K, Holmberg HC, Sperlich B. Wrist-Worn Wearables for Monitoring Heart Rate and Energy Expenditure While Sitting or Performing Light-to-Vigorous Physical Activity: Validation Study. JMIR Mhealth Uhealth. May 6 2020;8(5):e16716. doi:10.2196/16716
9. Hajj-Boutros G, Landry-Duval MA, Comtois AS, Gouspillou G, Karelis AD. Wrist-worn devices for the measurement of heart rate and energy expenditure: A validation study for the Apple Watch 6, Polar Vantage V and Fitbit Sense. Eur J Sport Sci. Jan 31 2022:1-13. doi:10.1080/17461391.2021.2023656
10. Kamal AA, Harness JB, Irving G, Mearns AJ. Skin photoplethysmography--a review. Comput Methods Programs Biomed. Apr 1989;28(4):257-69. doi:10.1016/0169-2607(89)90159-4
11. Wang R, Blackburn G, Desai M, et al. Accuracy of Wrist-Worn Heart Rate Monitors. JAMA Cardiol. Jan 1 2017;2(1):104-106. doi:10.1001/jamacardio.2016.3340
12. Gillinov S, Etiwy M, Wang R, et al. Variable Accuracy of Wearable Heart Rate Monitors during Aerobic Exercise. Med Sci Sports Exerc. Aug 2017;49(8):1697-1703. doi:10.1249/MSS.0000000000001284
13. Nuss KJ SJ, Archambault LJ, Schlemer EJ, Blake S, Courtney JB, Hulett NA, Li K. Accuracy of heart rate and energy expenditure estimations of wrist-worn and arm-worn Apple Watches. Journal for the Measurement of Physical Behaviour. 2018;2(3)doi:10.1123/jmpb.2018-0061
14. Wallen MP, Gomersall SR, Keating SE, Wisloff U, Coombes JS. Accuracy of Heart Rate Watches: Implications for Weight Management. PLoS One. 2016;11(5):e0154420. doi:10.1371/journal.pone.0154420
15. Thomson EA, Nuss K, Comstock A, et al. Heart rate measures from the Apple Watch, Fitbit Charge HR 2, and electrocardiogram across different exercise intensities. J Sports Sci. Jun 2019;37(12):1411-1419. doi:10.1080/02640414.2018.1560644
16. Kushhal A NS, Evans W, Gleadall-Siddall DO, Page R, O’Doherty AF, Carrol S, Ingle L, Abt G. Validity and Reliability of the Apple Watch for Measuring Heart Rate During Exercise. Int J Sports Med. 2017;38(14)doi:10.1055/s-0043-123585
17. Dooley EE DE, Golaszewski NM, Bartholomew JB. Estimating Accuracy at Exercise Intensities: A Comparative Study of Self-Monitoring Heart Rate and Physical Activity Wearable Devices. JMIR Mhealth Uhealth 2017;5(3)doi:10.2196/mhealth.7043
18. Bai Y HP, Mantis C, Welk GJ. . Comparative evaluation of heart rate-based monitors: Apple Watch vs Fitbit Charge HR. J Sports Sci. 2019;36(15)doi:10.1080/02640414.2017.1412235
19. Boudreaux BD HE, Hollander DB, Williams BM, Cormier CL, Naquin MR, Gillan WW, Gusew EE, Kraemer RR. Validity of Wearable Activity Monitors during Cycling and Resistance Exercise. Med Sci Sports Exerc. 2018;50(3)doi:10.1249/MSS.0000000000001471
20. Argent R, Hetherington-Rauth M, Stang J, et al. Recommendations for Determining the Validity of Consumer Wearables and Smartphones for the Estimation of Energy Expenditure: Expert Statement and Checklist of the INTERLIVE Network. Sports Medicine. 2022/08/01 2022;52(8):1817-1832. doi:10.1007/s40279-022-01665-4
21. Kwon S, Kim Y, Bai Y, Burns RD, Brusseau TA, Byun W. Validation of the Apple Watch for Estimating Moderate-to-Vigorous Physical Activity and Activity Energy Expenditure in School-Aged Children. Sensors (Basel). Sep 25 2021;21(19)doi:10.3390/s21196413
22. Fuller D AJ, Simango B, Dorani F, Bozorgi A, Luan H, Basset F. Using machine learning methods to predict physical activity types with Apple Watch and Fitbit data using indirect calorimetry as the criterion. Research Square. 2020;doi:10.21203/
23. Pope ZC ZN, Li X, Liu W, Gao Z. Accuracy of commercially available smartwatches in assessing energy expenditure during rest and exercise. JMPB. 2016;2(2)doi:10.1123/jmpb.2018-0037
24. Nuss KJ, Thomson EA, Courtney JB, et al. Assessment of Accuracy of Overall Energy Expenditure Measurements for the Fitbit Charge HR 2 and Apple Watch. Am J Health Behav. May 1 2019;43(3):498-505. doi:10.5993/AJHB.43.3.5
25. Zhang P, Burns RD, Fu Y, Godin S, Byun W. Agreement between the Apple Series 1, LifeTrak Core C200, and Fitbit Charge HR with Indirect Calorimetry for Assessing Treadmill Energy Expenditure. Int J Environ Res Public Health. Oct 10 2019;16(20)doi:10.3390/ijerph16203812
26. Fuller D, Anaraki JR, Simango B, et al. Using machine learning methods to predict physical activity types with Apple Watch and Fitbit data using indirect calorimetry as the criterion. Research Square; 2020.
27. Schwartz J OP, Takito MY, Saunders B, Dolan E, Franchini E, Rhodes RE, Bredin SSD, Coelho JP, Dos Santos P, Mazzuco M, Warburton DER. Translation, Cultural Adaptation, and Reproducibility of the Physical Activity Readiness Questionnaire for Everyone (PAR-Q+): The Brazilian Portuguese Version. Front Cardiovasc Med. 2021;26(8)doi:10.3389/fcvm.2021.712696
28. McLester CN, Nickerson BS, Kliszczewicz BM, McLester JR. Reliability and Agreement of Various InBody Body Composition Analyzers as Compared to Dual-Energy X-Ray Absorptiometry in Healthy Men and Women. J Clin Densitom. Jul - Sep 2020;23(3):443-450. doi:10.1016/j.jocd.2018.10.008
29. Arney BE GR, Fusco A, Cortis C, de Koning JJ, van Erp T, Jaime S, Mikat RP, Porcari JP, Foster C. Comparison of RPE (Rating of Perceived Exertion) Scales for Session RPE. Int J Sports Physiol Perform. 2019;14(7)doi:10.1123/ijspp.2018-0637
30. Jensen K, Jorgensen S, Johansen L. A metabolic cart for measurement of oxygen uptake during human exercise using inspiratory flow rate. Eur J Appl Physiol. Jul 2002;87(3):202-6. doi:10.1007/s00421-002-0616-2
31. Bruce RA, Kusumi, F., & Hosmer, D. Maximal oxygen intake and nomographic assessment of functional aerobic impairment in cardiovascular disease. Am Heart J. 1973;85(4)
32. Hanson NJ, Scheadler CM, Lee TL, Neuenfeldt NC, Michael TJ, Miller MG. Modality determines VO2max achieved in self-paced exercise tests: validation with the Bruce protocol. Eur J Appl Physiol. Jul 2016;116(7):1313-9. doi:10.1007/s00421-016-3384-0
33. Laukkanen RM VP. Heart rate monitors: state of the art. J Sports Sci. 1998;doi:10.1080/026404198366920
34. Germini F, Noronha N, Borg Debono V, et al. Accuracy and Acceptability of Wrist-Wearable Activity-Tracking Devices: Systematic Review of the Literature. J Med Internet Res. Jan 21 2022;24(1):e30791. doi:10.2196/30791
35. Navalta JW SW, Lyons TS. Ethical Issues Relating to Scientific Discovery in Exercise Science. Int J Exerc Sci. 2019;12(1):1-8.
36. Reed GF, Lynn F, Meade BD. Use of coefficient of variation in assessing variability of quantitative assays. Clin Diagn Lab Immunol. Nov 2002;9(6):1235-9. doi:10.1128/cdli.9.6.1235-1239.2002
37. Zurlo F, Larson K, Bogardus C, Ravussin E. Skeletal muscle metabolism is a major determinant of resting energy expenditure. J Clin Invest. Nov 1990;86(5):1423-7. doi:10.1172/JCI114857