Oxygenation Threshold Derived from Near-Infrared Spectroscopy: Reliability and Its Relationship with the First Ventilatory Threshold

S. van der Zwaard, R.T. Jaspers, I.J. Blokland, C. Achterberg, J.M. Visser, A.R. den Uil, M.J. Hofmijster, K. Levels, D.A. Noordhof, A. de Haan, J.J. de Koning, W.J. van der Laarse, C.J. de Ruiter

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Background
Near-infrared spectroscopy (NIRS) measurements of oxygenation reflect O2 delivery and utilization in exercising muscle and may improve detection of a critical exercise threshold.

Purpose
First, to detect an oxygenation breakpoint (Δ[O2HbMb-HHbMb]-BP) and compare this breakpoint to ventilatory thresholds during a maximal incremental test across sexes and training status. Second, to assess reproducibility of NIRS signals and exercise thresholds and investigate confounding effects of adipose tissue thickness on NIRS measurements.

Methods
Forty subjects (10 trained male cyclists, 10 trained female cyclists, 11 endurance trained males and 9 recreationally trained males) performed maximal incremental cycling exercise to determine Δ[O2HbMb-HHbMb]-BP and ventilatory thresholds (VT1 and VT2). Muscle haemoglobin and myoglobin O2 oxygenation ([HHbMb], [O2HbMb], SmO2) was determined in m. vastus lateralis. Δ[O2HbMb-HHbMb]-BP was determined by double linear regression. Trained cyclists performed the maximal incremental test twice to assess reproducibility. Adipose tissue thickness (ATT) was determined by skinfold measurements.

Results
Δ[O2HbMb-HHbMb]-BP was not different from VT1, but only moderately related (r = 0.58–0.63, p
Conclusion
Although the oxygenation threshold is reproducible and potentially a suitable exercise threshold, VT1 discriminates better across sexes and training status during maximal stepwise incremental exercise. Continuous-wave NIRS measurements are reproducible, but strongly affected by adipose tissue thickness.
Original languageEnglish
Article numbere0162914
Number of pages16
JournalPLoS ONE
Volume11
Issue number9
DOIs
Publication statusPublished - 2016

Cite this

van der Zwaard, S., Jaspers, R. T., Blokland, I. J., Achterberg, C., Visser, J. M., den Uil, A. R., ... de Ruiter, C. J. (2016). Oxygenation Threshold Derived from Near-Infrared Spectroscopy: Reliability and Its Relationship with the First Ventilatory Threshold. PLoS ONE, 11(9), [e0162914]. https://doi.org/10.1371/journal.pone.0162914