Complex and Contrast Training: Does Strength and Power Training Sequence Affect Performance-Based Adaptations in Team Sports? A Systematic Review and Meta-analysis.

Cormier, P, Freitas, TT, Rubio-Arias, JÁ, and Alcaraz, PE. Complex and contrast training: Does strength and power training sequence affect performance-based adaptations in team sports? A systematic review and meta-analysis. J Strength Cond Res 34(5): 1461-1479, 2020-The aims of this meta-analysis were to examine the effects of 2 different strength and power training sequences (complex: CPX; and contrast: CNT, training) on performance-based adaptations in team sports {lower-body strength (1 repetition maximum [1RM]), vertical jump (VJ), sprinting, and change of direction (COD) ability}, as well as identify factors potentially affecting said adaptations (i.e., athlete level, type of sport, intensity, and duration). CPX is the combination training that alternates biomechanically similar high load weight training exercises with lighter load power exercises, set for set (e.g., squats followed by countermovement jumps). CNT is the combination training where all high load strength exercises are performed at the beginning of the session and all lighter load power exercises at the end. After an electronic database search (PubMed, SPORTDiscus, and WoS), a total of 27 articles were included in the meta-analysis. The effects on outcomes were expressed as standardized mean differences (SMDs). Baseline to postintervention overall results for the studied variables: (a) 1RM: large effects for CPX (SMD = 2.01, 95% confidence interval [CI] 1.18-2.84) and CNT (SMD = 1.29, 95% CI 0.61-1.98); (b) VJ: large effects for CPX (SMD = 0.88, 95% CI 0.42-1.34) and medium effects for CNT (SMD = 0.55, 95% CI 0.29-0.81); (c) sprint: large effects for CPX (SMD = -0.94, 95% CI -1.33 to -0.54) and small effects for CNT (SMD = -0.27, 95% CI -0.92 to 0.39); and (d) COD: large effects for CPX (SMD = -1.17, 95% CI -1.43 to -0.90) and medium effects for CNT (SMD = -0.68, 95% CI -1.20 to -0.15). Regarding the studies that contained a control group: (a) 1RM: large effects for CPX (SMD = 1.61, 95% CI 1.12-2.10) and CNT (SMD = 1.38, 95% CI 0.30-2.46); (b) VJ: large effects for CPX (SMD = 0.85, 95% CI 0.45-1.25) and medium for CNT (SMD = 0.50, 95% CI 0.19-0.81); (c) sprint: medium effects for CPX (SMD = -0.69, 95% CI -1.02 to -0.36) and CNT (SMD = -0.51, 95% CI -0.90 to -0.11); and (d) COD: large effects for CPX (SMD = -0.83, 95% CI -1.08 to -0.59), and there were no control groups for CNT. In conclusion, both training interventions may lead to positive performance-based adaptations in team-sports with CPX interventions potentially leading to slightly greater effects.