Abstract / Summary
Objectives This systematic review aimed to evaluate the effects of high-intensity resistance training (HIRT), operationally defined as resistance protocols utilizing loads ≥ 75% of one-repetition maximum (1RM), on athletic performance outcomes—including muscular strength, power, jumping performance, speed, preplanned change-of-direction (COD) speed, and endurance—among elite athletes. Methods Following PRISMA 2020 guidelines, a systematic search was conducted in Web of Science, PubMed, Scopus and SPORTDiscus to identify studies that applied HIRT in elite athlete populations. Google Scholar was additionally utilized for forward and backward citation tracking. Twelve studies met the inclusion criteria and were assessed using the PEDro scale. Data on intervention characteristics, testing protocols, and performance outcomes were extracted and synthesized narratively. Results HIRT interventions (range: 5–18 weeks) demonstrated significant improvements in maximal strength ( e.g. , squat and bench press 1RM) and neuromuscular power-related outcomes across the majority of studies. Improvements in sprint speed, sport-specific velocity, and preplanned COD speed were also observed, although evidence for COD performance was limited to a single study. Endurance-related outcomes, including time to exhaustion, movement economy, and selected time-trial measures, generally favored HIRT, with no clear evidence of detrimental effects on aerobic-capacity-related outcomes. However, all included studies implemented HIRT within concurrent training programs rather than as an isolated intervention. Conclusions The available evidence suggests that HIRT may be an effective training component for improving strength, power, and selected performance outcomes in elite athletes when integrated into concurrent sport-specific training programs. The strongest support was observed for maximal strength and neuromuscular power, whereas evidence for preplanned COD speed remains preliminary and requires replication. Given the concurrent training designs, the absence of a formal GRADE assessment, and the generally small sample sizes, these findings should be interpreted as likely low-to-moderate certainty evidence rather than as proof of the isolated effects of HIRT. The review protocol was prospectively registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 6 January 2025 (Registration No.: CRD42025634254).