TY - JOUR
T1 - Determination of respiratory point compensation in healthy adults
T2 - Can non-invasive near-infrared spectroscopy help?
AU - Fontana, Federico Y.
AU - Keir, Daniel A.
AU - Bellotti, Cecilia
AU - De Roia, Gabriela F.
AU - Murias, Juan M.
AU - Pogliaghi, Silvia
N1 - Publisher Copyright:
© 2014 Sports Medicine Australia.
PY - 2015/9/1
Y1 - 2015/9/1
N2 - Objectives: We tested the hypothesis that the respiratory compensation point can be accurately determined in healthy participants during incremental cycling exercise using non-invasive near-infrared spectroscopy-derived measures of deoxygenated hemoglobin ( deoxyHb). Design: Validation study. Methods: 118 healthy men (average age 47±19 yrs, range 20-79 yrs) performed an incremental cycling test to exhaustion. Breath-by-breath pulmonary oxygen uptake (VO2) and other ventilatory and gas exchange variables were measured and used to determine respiratory compensation point. Vastus lateralis deoxyHb was monitored using a frequency domain multi-distance system near-infrared spectroscopy device and deoxyHb data were modeled with a piece-wise double-linear function from which the deoxyHb deflection point (deoxyHbDP) was determined. The absolute (Lmin-1) and relative (% maximal VO2 [VO2max]) VO2 values associated with the respiratory compensation point and deoxyHbDP were determined for each individual. Results: DeoxyHbDP increased as a function of exercise intensity up to a point (deoxyHbDP) after which the signal displayed a "near-plateau". The deoxyHbDP corresponded to a VO2 of 2.25±0.69Lmin-1 (74±12% VO2max) which was not significantly different from the VO2 at respiratory compensation point (2.28±0.70Lmin-1 and 74±10% VO2max, p<0.05). Both indices were highly correlated (r2=0.86) and Bland Altman analyses confirmed a non-significant bias for VO2 (-0.024Lmin-1) concomitant with a small imprecision of 0.26Lmin-1. Conclusions: During incremental cycling exercise, the VO2 associated with the onset of a plateau in near-infrared spectroscopy-derived deoxyHb occurs in coincidence with the VO2 at respiratory compensation point suggesting that respiratory compensation point can be accurately estimated, non-invasively, using near-infrared spectroscopy-derived deoxyHb in alternative to the use of ventilatory-based techniques.
AB - Objectives: We tested the hypothesis that the respiratory compensation point can be accurately determined in healthy participants during incremental cycling exercise using non-invasive near-infrared spectroscopy-derived measures of deoxygenated hemoglobin ( deoxyHb). Design: Validation study. Methods: 118 healthy men (average age 47±19 yrs, range 20-79 yrs) performed an incremental cycling test to exhaustion. Breath-by-breath pulmonary oxygen uptake (VO2) and other ventilatory and gas exchange variables were measured and used to determine respiratory compensation point. Vastus lateralis deoxyHb was monitored using a frequency domain multi-distance system near-infrared spectroscopy device and deoxyHb data were modeled with a piece-wise double-linear function from which the deoxyHb deflection point (deoxyHbDP) was determined. The absolute (Lmin-1) and relative (% maximal VO2 [VO2max]) VO2 values associated with the respiratory compensation point and deoxyHbDP were determined for each individual. Results: DeoxyHbDP increased as a function of exercise intensity up to a point (deoxyHbDP) after which the signal displayed a "near-plateau". The deoxyHbDP corresponded to a VO2 of 2.25±0.69Lmin-1 (74±12% VO2max) which was not significantly different from the VO2 at respiratory compensation point (2.28±0.70Lmin-1 and 74±10% VO2max, p<0.05). Both indices were highly correlated (r2=0.86) and Bland Altman analyses confirmed a non-significant bias for VO2 (-0.024Lmin-1) concomitant with a small imprecision of 0.26Lmin-1. Conclusions: During incremental cycling exercise, the VO2 associated with the onset of a plateau in near-infrared spectroscopy-derived deoxyHb occurs in coincidence with the VO2 at respiratory compensation point suggesting that respiratory compensation point can be accurately estimated, non-invasively, using near-infrared spectroscopy-derived deoxyHb in alternative to the use of ventilatory-based techniques.
KW - Anaerobic metabolism
KW - Exercise prescription
KW - Functional evaluation
KW - Non-invasive techniques
UR - http://www.scopus.com/inward/record.url?scp=84938744007&partnerID=8YFLogxK
U2 - 10.1016/j.jsams.2014.07.016
DO - 10.1016/j.jsams.2014.07.016
M3 - Article
C2 - 25153251
AN - SCOPUS:84938744007
SN - 1440-2440
VL - 18
SP - 590
EP - 595
JO - Journal of Science and Medicine in Sport
JF - Journal of Science and Medicine in Sport
IS - 5
ER -