title: Estimation of maximal heart rate using the relationship between heart rate variability and exercise intensity in 40-67 years old men.
abstract: Large interindividual variation in maximal heart rate (HRmax) may not be accounted for by age alone. In order to evaluate a novel method in the prediction of HRmax, this study examined the profile of HR variability (HRV) during exercise in 40-67 years old men (n = 74). R-R intervals were recorded during supine rest and during a graded exercise test by cycle ergometry until exhaustion. A third-degree polynomial function was fitted to the HRV data recorded during exercise to represent the HRV profile of each subject. The instantaneous beat-to-beat R-R interval variability (SD1), high (HF) and low frequency power decreased between all consecutive exercise intensities (P < 0.033). The relationship between HRmax and a variable illustrating the declining rate of HF (HRHF50%) was stronger (r = 0.50, P < 0.001) than between HRmax and age (r = -0.36, P < 0.01). The regression analysis showed that a more accurate estimation of HR(max) was attained when HRV was used in the equation in addition to age: HRmax = 160.633-0.603(age) + 0.441(HRHF50%) (SEE = 9.8 bpm vs. 11.6 bpm in the equation based on age alone). The decline of HRV during incremental exercise seems to be useful for accurate estimation of maximal heart rate.
authors.affiliation: Department of Biology of Physical Activity, University of Jyväskylä, PO Box 35, 40014 Jyväskylä, Finland. laura.karavirta@sport.jyu.fi
authors.forename: Laura
authors.initials: L
authors.lastname: Karavirta
authors.forename: Mikko P
authors.initials: MP
authors.lastname: Tulppo
authors.forename: Kai
authors.initials: K
authors.lastname: Nyman
authors.forename: David E
authors.initials: DE
authors.lastname: Laaksonen
authors.forename: Teemu
authors.initials: T
authors.lastname: Pullinen
authors.forename: Raija T
authors.initials: RT
authors.lastname: Laukkanen
authors.forename: Hannu
authors.initials: H
authors.lastname: Kinnunen
authors.forename: Arja
authors.initials: A
authors.lastname: Häkkinen
authors.forename: Keijo
authors.initials: K
authors.lastname: Häkkinen
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D002320:Cardiovascular Physiological Phenomena; D004562:Electrocardiography; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007773:Lactates / Q000097:blood; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology; D012044:Regression Analysis; D012146:Rest / Q000502:physiology
chemical_list: D007773:Lactates