Acute effect of cross training on flexibility levels: a narrative review

Abstract

Objective: To analyze the available evidence on the acute effects of a cross training session on practitioners’ flexibility. Methods: A narrative, qualitative and descriptive review was conducted, with searches in October 2026 in PubMed, SciELO and Google Scholar. Peer-reviewed articles published between 2015 and 2026 in Portuguese, English or Spanish were considered. Twenty-six studies were included and grouped into four categories: acute responses to exercise, acute effects of cross training, chronic adaptations, and relationships between range of motion, technique and injuries. Results: Stretching, warm-up, foam rolling and some resistance training sessions were associated with acute, generally temporary, increases in range of motion. However, the only study identified that assessed practitioners before and after a typical high-intensity session observed a reduction in the sit-and-reach test immediately after training, with values close to baseline after 24 hours. Studies on chronic effects showed divergent results. Conclusion: Evidence on the acute response to cross training is scarce and does not allow a uniform effect to be established. The response may depend on session characteristics, assessment timing and the instrument used. Controlled studies with joint-specific measures and assessments at different times after training are needed.