Selective Effect of Different High-Intensity Running Protocols on Resistance Training Performance.

Pérez-Castilla, A, García-Pinillos, F, Miras-Moreno, S, Ramirez-Campillo, R, García-Ramos, A, and Ruiz-Alias, SA. Selective effect of different high-intensity running protocols on resistance training performance. J Strength Cond Res 37(6): e369-e375, 2023-This study aimed to explore the acute effect of 2 high-intensity running protocols (high-intensity interval training [HIIT] and sprint interval training [SIT]) on resistance training (RT) performance and their combined effect on the lower-body maximal neuromuscular capacities. Eighteen healthy subjects randomly completed 3 experimental protocols: only RT, HIIT + RT, and SIT + RT. Characteristics of the RT protocol include 3 back-squat sets of 10 repetitions or 20% velocity loss against 60% of 1 repetition maximum with 3 minutes of interset rest. Characteristics of the high-intensity running protocols include HIIT (4 intervals of 4 minutes at ∼110% of functional threshold power with 3 minutes of interinterval rest) and SIT (6 all-out sprints of 30 seconds with 4 minutes and 24 seconds of interinterval rest). The force-velocity relationship (maximal values of force [ F0 ], velocity [ v0 ], and power [P max ]) was evaluated at the beginning and at the end of each experimental protocol. The number of back-squat repetitions ( p = 0.006; effect size [ES] = -0.96), fastest velocity ( p = 0.003; ES = -0.63), and average velocity ( p = 0.001; ES = -0.73) were lower for the SIT + RT protocol compared with the RT protocol, but no significant differences were observed between the RT and HIIT + RT ( p ≥T0.057; ES ≤.-0.46, except -0.82 for the number of back-squat repetitions) and HIIT + RT and SIT + RT ( p ≥T0.091; ES .0-0.35) protocols. The 3 protocols induced comparable decreases in v0 and P max ( F(2,34) 2,0.96; p ≥ 0.393), but F0 tended to decrease after the SIT + RT protocol and to increase after the RT and HIIT + RT protocols ( F(2,34) = 4.37; p = 0.035). Compared with RT alone, the data suggest that SIT deteriorates RT quality and F0 capacity more than long-interval HIIT.