Determination of respiratory point compensation in healthy adults: Can non-invasive near-infrared spectroscopy help?

作者：Fontana Federico Y; Keir Daniel A; Bellotti Cecilia; De Roia Gabriela F; Murias Juan M; Pogliaghi Silvia^*

来源：Journal of Science and Medicine in Sport, 2015, 18(5): 590-595.

DOI：10.1016/j.jsams.2014.07.016

• Functional evaluation
• Exercise prescription
• Non-invasive techniques
• Anaerobic metabolism

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 ((V) over dotO(2)) 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 (deoxyHb(DP)) was determined. The absolute (L min(-1)) and relative (% maximal (V) over dotO(2) [(V) over dotO(2max)]) (V) over dotO(2) values associated with the respiratory compensation point and deoxyHb(DP) were determined for each individual.
Results: DeoxyHb increased as a function of exercise intensity up to a point (deoxyHb(DP)) after which the signal displayed a "near-plateau". The deoxyHb(DP) corresponded to a (V) over dotO(2) of 2.25 +/- 0.69 L min(-1) (74 +/- 12% (V) over dotO(2max)) which was not significantly different from the (V) over dotO(2) at respiratory compensation point (2.28 +/- 0.70 L min(-1) and 74 +/- 10% (V) over dotO(2max), p < 0.05). Both indices were highly correlated (r(2) = 0.86) and Bland Altman analyses confirmed a non-significant bias for (V) over dotO(2) (-0.024 L min(-1)) concomitant with a small imprecision of 0.26 L min(-1).
Conclusions: During incremental cycling exercise, the (V) over dotO(2) associated with the onset of a plateau in near-infrared spectroscopy-derived deoxyHb occurs in coincidence with the (V) over dotO(2) 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.

• 出版日期2015-9