Fig. 1.

Effects of sex and obesity on resting and exercise-induced irisin secretion. Circulating irisin concentrations increase in normal-weight (a) but not in obese men and women (b) immediately after acute aerobic exercise. Resting irisin levels are higher in obese versus normal-weight participants (c). a *p ≤ 0.05 women versus men immediately after exercise, ^§ p ≤ 0.01 women 0′ vs rest, ⁺ p ≤ 0.05 men 0′ versus rest and women 10′ versus rest, c ***p ≤ 0.001 obese versus normal-weight subjects at rest