Compatibility of adaptive responses with combining strength and endurance training

Impairment in strength development has been demonstrated with combined strength and endurance training as compared with strength training alone. The purpose of this study was to examine the effects of combining conventional 3 d·wk⁻¹ strength and endurance training on the compatibility of improving both V̇O_2peak and strength performance simultaneously. Sedentary adult males, randomly assigned to one of three groups (N = 10 each), completed 10 wk of training. A strength-only (S) group performed eight weight-training exercises (4 sets/exercise, 5–7 repetitions/set), an endurance-only (E) group performed continuous cycle exercise (50 min at 70% heart rate reserve), and a combined (C) group performed the same S and E exercise in a single session. S and C groups demonstrated similar increases (P < 0.0167) in 1RM squat (23% and 22%) and bench press (18% for both groups), in maximal isometric knee extension torque (12% and 7%), in maximal vertical jump (6% and 9%), and in fat-free mass (3% and 5%). E training did not induce changes in any of these variables. V̇O_2peak (ml·kg⁻¹min⁻¹) increased (P < 0.01) similarity in both E (18%) and C (16%) groups. Results indicate 3 d·wk⁻¹ combined training can induce substantial concurrent and compatible increases in V̇O_2peak and strength performance.