Table 3.

Associations of Fndc5/irisin with parameters of metabolic phenotype: multiple linear regression model

	Fndc5 mRNA skeletal muscle		Fndc5 mRNA adipose tissue		Irisin circulation		Pgc1α mRNA skeletal muscle
	β	P	β	P	β	P	β	P
Parameter	coeff.	value	coeff.	value	coeff.	value	coeff.	value
M–value/insulin (mg kg–1 min–1 μU–1 ml–1)	—	—	0.754	0.006	—	—	0.571	0.019
Lean body mass (kg)	0.470	0.085	—	—	—	—	–0.657	0.002
Waist circumference (cm)	—	—	—	—	–0.473	0.033	–0.602	0.018
Triglycerides (mmol l–1)	—	—	–0.615	0.046	—	—	—	—
Moderate and high intensity activity (%)	—	—	—	—	0.480	0.027	—	—
RQ fasted state	—	—	—	—	–0.365	0.138	–0.515	0.058
ΔRQ (clamp-fasted)	—	—	—	—	—	—	0.557	0.047
Resting metabolic rate (kcal (24 h)–1 (kg LBM)–1)	—	—	—	—	0.479	0.027	—	—

Adjusted for age and BMI. β coeff., β coefficient; clamp, euglycaemic–hyperinuslinaemic clamp; LBM, lean body mass; RQ, respiratory quotient.