Resistance exercise induces a greater irisin response than endurance exercise

Objective. We determined detailed time-course changes in the irisin response to acute exercise using different exercise modes. Methods. In experiment 1, seven healthy males rested for 12 h (8:00-20:00) to determine the diurnal variation in plasma irisin concentration. In experiment 2, 10 healthy males conducted three exercises to clarify time-course changes in plasma irisin concentration over 6 h, using a randomized crossover design. The resistance exercise (R) trial consisted of eight exercises of 12 repetitions with 3-4 sets at 65% of one repetition maximum (1RM). The endurance exercise (E) trial consisted of 60 mm of pedaling at 65% of maximal oxygen uptake (VO2max). In the combined mode (R + E) trial, 30 min of endurance exercise was preceded by 30 min of resistance exercise. Results. In experiment 1, no significant changes in plasma irisin concentration were observed over 12 h. In experiment 2, the R trial showed a marked increase in plasma irisin concentration 1 h after exercise (P < 0.05), but not in the E or R + E trials. The area under the curve (AUC) for irisin concentrations for 6 h after exercise was significantly higher in the R trial than in the R + E trial (P < 0.05). The AUC for irisin concentrations was significantly correlated with AUC values for blood glucose, lactate, and serum glycerol (r = 0.37, 0.45, 0.45, respectively. P < 0.05). Conclusions. Resistance exercise resulted in significantly greater irisin responses compared with endurance exercise alone, and resistance and endurance exercises combined. (C) 2015 Elsevier Inc. All rights reserved.