title: Noninvasive Determination of Anaerobic Threshold Based on the Heart Rate Deflection Point in Water Cycling.
abstract: This study compared heart rate (HR), oxygen uptake (VO2), percentage of maximal HR (%HRmax), percentage of maximal VO2, and cadence (Cad) related to the anaerobic threshold (AT) during a water cycling maximal test between heart rate deflection point (HRDP) and ventilatory (VT) methods. In addition, the correlations between both methods were assessed for all variables. The test was performed by 27 men in a cycle ergometer in an aquatic environment. The protocol started at a Cad of 100 b · min(-1) for 3 minutes with subsequent increments of 15 b · min(-1) every 2 minutes until exhaustion. A paired two-tailed Student's t-test was used to compare the variables between the HRDP and VT methods. The Pearson product-moment correlation test was used to correlate the same variables determined by the 2 methods. There was no difference in HR (166 ± 13 vs. 166 ± 13 b · min(-1)), VO2 (38.56 ± 6.26 vs. 39.18 ± 6.13 ml · kg(-1) · min(-1)), %HRmax (89.24 ± 3.84 vs. 89.52 ± 4.29%), VO2max (70.44 ± 7.99 vs. 71.64 ± 8.32%), and Cad (174 ± 14 b · min(-1) vs. 171 ± 8 b · min(-1)) related to AT between the HRDP and VT methods. Moreover, significant relationships were found between the methods to determine the AT for all variables analyzed (r = 0.57-0.97). The estimation of the HRDP may be a noninvasive and easy method to determine the AT, which could be used to adapt individualized training intensities to practitioners during water cycling classes.
authors.affiliation: 1Physical Education School, Federal University of Pelotas, Pelotas, Brazil; 2Research Group in Sport and Health, University of Valencia, Valencia, Spain; and 3Physical Education School, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Stephanie S
authors.initials: SS
authors.lastname: Pinto
authors.forename: Roxana M
authors.initials: RM
authors.lastname: Brasil
authors.forename: Cristine L
authors.initials: CL
authors.lastname: Alberton
authors.forename: Hector K
authors.initials: HK
authors.lastname: Ferreira
authors.forename: Natália C
authors.initials: NC
authors.lastname: Bagatini
authors.forename: Joaquin
authors.initials: J
authors.lastname: Calatayud
authors.forename: Juan C
authors.initials: JC
authors.lastname: Colado
mesh_terms: D000328:Adult; D015308:Anaerobic Threshold / Q000502:physiology*; D005080:Exercise Test / Q000379:methods*; D064368:Healthy Volunteers; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D012044:Regression Analysis