Introduction The assessment of the anaerobic thresh old (AT) from heart rate variability (HRV) collecte d during graded exercise testing has gained increasing interest in the last years (Cotti n et al., 2007). Recent studies, focusing on swimmi ng (Di Michele et al., 2012) and roller skiing (Mourot et al., in press), refined this meth od by analysing the respiratory spectral component isolated from the high-frequency component that originates from cardiolocomotor inte ractions. In line with such approach, this study ai med to estimate the AT from the analysis of the actual respiratory component of the HRV spectrum in a running test. Methods Ten male s occer players (22 ± 2 years) completed an incremental running test. The speed wa s initially set at 8.5 km/h, and was increased by 0 .5 km/h every minute until ex- haustion. Respiratory parameters were collected usi ng a portable gas analyser (Cosmed K4b2) to calcula te the reference AT , while R-R intervals were collected using a heart rate monitor (Polar RS800cx). A short-time Fourier transform wa s used to estimate the power spec- tral density of the HRV signal. The AT was associat ed to an abrupt increase of the HRV spectral power of a 0.15 Hz wide frequency range centered at the estimated breathing frequency. Resu lts The AT HR values determined from HRV (185.2 ± 8 .1 bpm) and from the ventilato- ry-based method (186.0 ± 8.9 bpm) were highly corre lated (r=0.95, p<0.05), and not significantly diffe rent (p>0.05). The 95% limits of agreement for AT HR were -5.6 to 4.0 bpm. Discussio n The results showed that AT estimation from HRV in a running test is very accurate when considering the actual respiratory component r ather than the whole high-frequency region of the H RV spectrum. The present findings provide further support to the use of the HRV-based approach as a practical and non-invasive method to measure the AT. Refer- ences Cottin F, Medigue C, Lopes P, Lepretre PM, He ubert L, Billat V. (2007). Int J Sport Med, 28, 287 -294. Di Michele R, Gatta G, Di Leo A, Cortesi M, Andina F, Tam E, Da Boit M, Merni F. (20 12). J Strength Cond Res, 26, 3059-3066. Mourout L, Fabre N, Savoldelli A, Schena F. (2014). Int J Sports Physol Perform, in press
ANAEROBIC THRESHOLD ASSESSMENT FROM HEART RATE VARIABILITY IN RUNNING: USING THE ACTUAL RESPIRATORY SPECTRAL COMPONENT
DI MICHELE, ROCCO;MERNI, FRANCO
2014
Abstract
Introduction The assessment of the anaerobic thresh old (AT) from heart rate variability (HRV) collecte d during graded exercise testing has gained increasing interest in the last years (Cotti n et al., 2007). Recent studies, focusing on swimmi ng (Di Michele et al., 2012) and roller skiing (Mourot et al., in press), refined this meth od by analysing the respiratory spectral component isolated from the high-frequency component that originates from cardiolocomotor inte ractions. In line with such approach, this study ai med to estimate the AT from the analysis of the actual respiratory component of the HRV spectrum in a running test. Methods Ten male s occer players (22 ± 2 years) completed an incremental running test. The speed wa s initially set at 8.5 km/h, and was increased by 0 .5 km/h every minute until ex- haustion. Respiratory parameters were collected usi ng a portable gas analyser (Cosmed K4b2) to calcula te the reference AT , while R-R intervals were collected using a heart rate monitor (Polar RS800cx). A short-time Fourier transform wa s used to estimate the power spec- tral density of the HRV signal. The AT was associat ed to an abrupt increase of the HRV spectral power of a 0.15 Hz wide frequency range centered at the estimated breathing frequency. Resu lts The AT HR values determined from HRV (185.2 ± 8 .1 bpm) and from the ventilato- ry-based method (186.0 ± 8.9 bpm) were highly corre lated (r=0.95, p<0.05), and not significantly diffe rent (p>0.05). The 95% limits of agreement for AT HR were -5.6 to 4.0 bpm. Discussio n The results showed that AT estimation from HRV in a running test is very accurate when considering the actual respiratory component r ather than the whole high-frequency region of the H RV spectrum. The present findings provide further support to the use of the HRV-based approach as a practical and non-invasive method to measure the AT. Refer- ences Cottin F, Medigue C, Lopes P, Lepretre PM, He ubert L, Billat V. (2007). Int J Sport Med, 28, 287 -294. Di Michele R, Gatta G, Di Leo A, Cortesi M, Andina F, Tam E, Da Boit M, Merni F. (20 12). J Strength Cond Res, 26, 3059-3066. Mourout L, Fabre N, Savoldelli A, Schena F. (2014). Int J Sports Physol Perform, in pressI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
