Are Strength Adaptations Reflected in Changes in Sprint Acceleration Performance in Highly Trained Team Sport...

Holmberg, PM, James, LP, Lamont, HS, and Kelly, VG. Are strength adaptations reflected in changes in sprint acceleration performance in highly trained team sport athletes? J Strength Cond Res 40(6): 663-675, 2026-This study examined whether strength adaptations were reflected in sprint acceleration performance during a 9-week periodized training intervention. Nineteen highly trained male team sport athletes (age: 20.16 ± 1.90 years, height: 177.46 ± 8.12 cm, body mass: 73.61 ± 8.24 kg, 1-repetition maximum [1RM] back squat: 106.58 ± 16.23 kg, 1.46 ± 0.23 kg·BM -1 ) completed strength (countermovement jump, maximal 10 rebound jump, isometric squat, and 1RM back squat) and 20-m sprint assessments on 3 occasions (baseline, mid-, and post-test). Net peak force increased at mid- ( Z = 3.58, p < 0.001, r = 0.82, large effect) and post-test ( Z = 3.70, p < 0.001, r = 0.85, large effect) relative to baseline. Countermovement jump height ( Z = 3.42, p = 0.001, r = 0.79, large effect) and reactive strength index ( Z = 2.50, p = 0.013, r = 0.57, large effect) were greater at post-test than baseline. One-repetition maximum back squat strength was greater at post-test than at mid-test ( Z = 3.94, p < 0.001, r = 0.90, large effect) and baseline ( Z = 3.86, p < 0.001, r = 0.81, large effect). However, 0-10 m and 0-20 m sprint times only improved at post-test relative to mid-test ( Z = -3.34, -3.37, p = 0.001-0.004, r = -0.77, large effect) and baseline ( Z = -2.88, -3.16, p = 0.001-0.002, r = -0.66, -0.73, large effect), suggesting a delayed performance effect. These findings may guide the design of training programs aimed at enhancing sprint acceleration in team sport athletes.