Table 3.

Relationship between parameters determined by near-infrared time-resolved spectroscopy (NIR_TRS) under thermoneutral or cold condition and pulmonary oxygen uptake during cold exposure.

					Correlation (r2)
					Supraclavicular region					Deltoid (forearm) region
Ref. no.	Instrument	n	Study design	Parameters	${\mu }_{\text{s}}^{\prime }$	Oxy-Hb	Deoxy-Hb	Total-Hb	StO2	${\mu }_{\text{s}}^{\prime }$	Oxy-Hb	Deoxy-Hb	Total-Hb	StO2
Nirengi et al. (37)	NIRTRS	18	Cross-sectional	CIT 27°C	0.00	0.38*	0.49*	0.41*	0.14	0.09	0.06	0.04	0.06	0.04
				CIT 19°C	0.08	0.24*	0.16	0.23*	0.01	0.15	0.02	0.09	0.04	0.06

Results of NIR_TRS parameters [tissue-oxygenated hemoglobin (oxy-Hb), deoxygenated Hb (deoxy-Hb), total Hb (total-Hb), tissue Hb oxygen saturation (StO₂,), and optical scattering parameters] and cold-induced thermogenesis (CIT) for healthy men under thermoneutral (27°C) or cold condition (19°C) are presented.

${\mu }_{\text{s}}^{\prime }$, reduced scattering coefficient determined by NIR_TRS.

^*P < 0.05.