Resisted Sprint Training Impact on Sprint across Distances: A Systematic Review and Meta-Analysis

Introduction: Sprint performance is a critical component in many sports, and Resisted Sprint Training (RST) is widely used to enhance acceleration and speed. However, the effectiveness of different RST protocols across various sprint distances remains unclear. Objective: This systematic review and meta-analysis aimed to evaluate the impact of RST using sleds and load vests on sprint performance over 5, 10, 20, and 30-meter distances. Methodology: The study followed PRISMA guidelines, conducting a comprehensive literature search across 16 electronic databases (e.g., PubMed, Web of Science) in April 2023. Search terms included "sled sprint training," "resisted sprint training," and "heavy sled training." Inclusion criteria targeted randomized clinical trials with pre-post intervention protocols lasting at least four weeks, focusing on both athletes and non-athletes in field, court, and track sports. Studies using elastics or parachutes, or those lacking load or timing data, were excluded. From 311 articles identified, 8 met the inclusion criteria. Results: The meta-analysis revealed significant improvements in sprint performance, particularly in protocols utilizing sleds, horizontal force application, and load prescriptions of 7.5%-15% of body weight. Performance enhancements were observed across 5-meter and 30-meter distances, with maturational stage playing a role in younger athletes' responses. Discussion: The findings align with previous research emphasizing the benefits of horizontal resistance and optimal load application in sprint training. However, gaps remain in standardizing load classifications and comparing sled versus vest-based protocols. Conclusions: RST interventions can effectively improve sprint performance, but individualized load prescriptions and training adaptations are essential.