Comparison of Weightlifting, Traditional Resistance Training and Plyometrics on Strength, Power and Speed: A Systematic Review with Meta‑Analysis

Background Weightlifting training (WLT) is commonly used to improve strength, power and speed in athletes. However, to date, WLT studies have either not compared training efects against those of other training methods, or been limited by small sample sizes, which are issues that can be resolved by pooling studies in a meta-analysis. Therefore, the objective of this systematic review with meta-analysis was to evaluate the efects of WLT compared with traditional resistance training (TRT), plyometric training (PLYO) and/or control (CON) on strength, power and speed. Methods The systematic review included peer-reviewed articles that employed a WLT intervention, a comparison group (i.e. TRT, PLYO, CON), and a measure of strength, power and/or speed. Means and standard deviations of outcomes were converted to Hedges’ g efect sizes using an inverse variance random-efects model to generate a weighted mean efect size (ES). Results Sixteen studies were included in the analysis, comprising 427 participants. Data indicated that when compared with TRT, WLT resulted in greater improvements in weightlifting load lifted (4 studies, p=0.02, g=1.35; 95% CI 0.20–2.51) and countermovement jump (CMJ) height (9 studies, p=0.00, g=0.95; 95% CI 0.04–1.87). There was also a large efect in terms of linear sprint speed (4 studies, p=0.13, g=1.04; 95% CI−0.03 to 2.39) and change of direction speed (CODS) (2 studies, p=0.36, g=1.21; 95% CI −1.41 to 3.83); however, this was not signifcant. Interpretation of these fndings should acknowledge the high heterogeneity across the included studies and potential risk of bias. WLT and PLYO resulted in similar improvements in speed, power and strength as demonstrated by negligible to moderate, non-signifcant efects in favour of WLT for improvements in linear sprint speed (4 studies, p=0.35, g=0.20; 95% CI−0.23 to 0.63), CODS (3 studies, p=0.52, g=0.17; 95% CI−0.35 to 0.68), CMJ (6 studies, p=0.09, g=0.31; 95% CI−0.05 to 0.67), squat jump performance (5 studies, p=0.08, g=0.34; 95% CI−0.04 to 0.73) and strength (4 studies, p=0.20, g=0.69; 95% CI−0.37 to 1.75). Conclusion Overall, these fndings support the notion that if the training goal is to improve strength, power and speed, supplementary weightlifting training may be advantageous for athletic development. Whilst WLT and PLYO may result in similar improvements, WLT can elicit additional benefts above that of TRT, resulting in greater improvements in weightlifting and jumping performance.