50-meter freestyle performance: a systematic review of upper limb strength, lower limb explosive power, and swimming technique determinants (2020–2026)

Abstract

The review followed the PRISMA 2020 framework and was conducted using Scopus as the primary information source, applying a Boolean strategy combining swimming, strength, explosive-power, and technique constructs within title, abstract, and keyword fields. The search returned 183 records, which were screened against predefined eligibility criteria restricting inclusion to English-language original articles and reviews directly addressing strength, power, or technical determinants of swimming performance. After title and abstract screening and full-text assessment, 50 studies were retained for qualitative and thematic synthesis. Included studies were evaluated by the FICO framework (Focus, Information, Context, Outcome); As the designs and outcome measures of the studies were highly different, no meta-analyses effect sizes are reported and the findings are combined narratively. Three thematic findings emerged. First, upper limb and trunk strength, expressed through tethered force and dry-land resistance capacity, are consistently associated with stroke propulsion and sprint velocity, although the strength-performance relationship is moderated by competitive level. Second, lower limb explosive power, assessed through jump and force-plate measures, is a robust determinant of start and turn performance, phases that contribute disproportionately to total 50-m time. Third, technical variables, particularly stroke length and stroke-rate regulation, mediate the translation of physical capacity into measurable velocity. Across studies, maximal-strength, plyometric, and complex training emerged as the most effective dry-land modalities. The review indicates that sprint freestyle performance is best modelled as an integrated outcome of force production, explosive power, and technical efficiency rather than any single capacity. Practically, the findings support multimodal conditioning that couples heavy resistance and plyometric work with technique-focused practice. Methodological heterogeneity and a scarcity of longitudinal designs are identified as priorities for future research.