Effect of intra-session exercise sequence on the load–velocity relationship variables after a concurrent sprint interval and resistance training program

This study aimed to examine the effects of altering the intra-session exercise sequence of a concurrent training program on the load–velocity relationship variables obtained from different compound exercises. Physically active subjects (n = 24, age = ∼21 years) were assigned to one group that performed sprint interval training (sprints: 4–6; intensity: all-out; duration: 30 s; rest: 4 min) followed by resistance training (exercises: back squat and bench press; sets per exercise: 4–6; load: 60–80% of the one-repetition maximum; repetition in reserve: 6–1; rest: 2 min) (SIT + RT) or another group that performed the opposite sequence (RT + SIT). Exercises modes were separated by 10 min. Both groups trained three times per week over an eight-week period. The individualized load–velocity relationships were assessed before and after training through an incremental loading test during the back squat and bench press exercises and three variables were subsequently calculated: load-axis intercept (L₀), velocity-axis intercept (v₀), and area under the line (A_line = L₀⋅v₀/2). Regardless of exercise sequence, both groups increased L₀ (ES range = 0.78–0.91) and A_line (ES range = 0.50–0.55) but decreased v₀ (ES range = −0.36 to −0.46) during the back squat exercise, while all load–velocity relationship variables were increased (ES range = 0.04–2.20) during the bench press exercise. The SIT + RT group showed a moderately greater bench press v₀ increase compared to the RT + SIT group (ES = −1.07). These results indicate that both intra-session exercise sequences can induce comparable improvements in the load–velocity relationship variables after an eight-week concurrent training program.