The effect of an aerobic training program on the electrical remodeling of the heart: high-frequency components of the signal-averaged electrocardiogram are predictors of the maximal aerobic power

Abstract

Increased heart rate variability (HRV) and high-frequency content of the terminal region of the ventricular activation of signal-averaged ECG (SAECG) have been reported in athletes. The present study investigates HRV and SAECG parameters as predictors of maximal aerobic power (VO 2 max) in athletes. HRV, SAECG and VO 2 max were determined in 18 high-performance long-distance (25 ± 6 years; 17 males) runners 24 h after a training session. Clinical visits, ECG and VO 2 max determination were scheduled for all athletes during thew training period. A group of 18 untrained healthy volunteers matched for age, gender, and body surface area was included as controls. SAECG was acquired in the resting supine position for 15 min and processed to extract average RR interval (Mean-RR) and root mean squared standard deviation (RMSSD) of the difference of two consecutive normal RR intervals. SAECG variables analyzed in the vector magnitude with 40-250 Hz band-pass bi-directional filtering were: total and 40-µV terminal (LAS40) duration of ventricular activation, RMS voltage of total (RMST) and of the 40-ms terminal region of ventricular activation. Linear and multivariate stepwise logistic regressions oriented by inter-group comparisons were adjusted in significant variables in order to predict VO 2 max, with a P < 0.05 considered to be significant. VO 2 max correlated significantly (P < 0.05) with RMST (r = 0.77), Mean-RR (r = 0.62), RMSSD (r = 0.47), and LAS40 (r = -0.39). RMST was the independent predictor of VO 2 max. In athletes, HRV and high-frequency components of the SAECG correlate with VO 2 max and the high-frequency content of SAECG is an independent predictor of VO 2 max.

Heart Rate Variability Indexes as a Marker of Chronic Adaptation in Athletes: A Systematic Review

“…The differences in genders and ages are well established in the literature, women show slightly lower HRV values and higher parasympathetic activity . Nevertheless, as observed in three studies included in this review, the use of heterogeneous groups as part of the same sample did not appear to influence the results.…”

“…The total number of athletes was about 333 males and females, aged between 17 and 40 years, who practiced different sports (running, cycling, swimming, canoeing, athletics, skating, volleyball, football, basketball, rugby, and triathlon). For the sample characterization, seven studies used the VO 2 as a physiological measure, seven studies reported the length of time that the athletes had practiced the sport (over 2 years), and eight studies selected athletes participating in national, regional, or international competitions . No study reported the athlete's training phase during the course of the experiment.…”

“…Of the studies that reported preevaluation recommendations, eight requested the participants to avoid exercising before the day of the experiment, for periods of 12–48 h before the experiment . The schedules for the evaluations varied from 08:00 to 12:00 in the morning, and from 13:00 to 16:00 in the afternoon . Breathing control was used in three studies and only one of them used free and controlled breathing .…”

“…The provided mean and standard deviation values from 14 articles were included in the quantitative analyses of the Cohen's ES, whose large and moderate values were showed in time (Table ) and frequency domain (Table ).…”

“…The HRV data were provided by articles or by e‐mail through contact with the authors. Missing values are due to graphic representations in the articles and mismatched data received by e‐mail .…”