Global Trends in RCTs Related to High-Intensity Interval Training and its Multi-Dimensional Application: A PubMed Review – Based Bibliometric Analysis from 2000 to 2026

Abstract

Studies on high-intensity interval training (HIIT) have shifted from improving athletic performance to clinical interventions addressing various pathological conditions across diverse populations. However, the structure of its randomized controlled trials (RCTs) remains unmapped. The PubMed database was searched for human RCTs published between 2000 and 2026, yielding 694 eligible trials after screening. Biblioshiny and VOSviewer were used to identify publication growth, author and institutional collaboration networks, the most influential and contributing authors in HIIT-related RCTs, and thematic analyses of research hotspots and keywords based on their occurrence. The RCTs appeared in 247 journals, with an annual growth of 18.84%, a peak of 132 published RCTs in 2025 and 34.29% international co-authorship. Among 4530 contributing authors, Ulrik Wisloff from the Norwegian University of Science & Technology is the most productive author, and the University of Copenhagen is the leading institute in conducting RCTs related to HIIT. The thematic analysis of keywords showed three emerging research areas: (1) Physiological and ergogenic correlates of HIIT, (2) Metabolic and cardiometabolic correlates of HIIT, and (3) Rehabilitation and clinical applications of HIIT, particularly in stroke and cancer patients. The research trends of RCTs related to HIIT have expanded from a sports context to a metabolic, oncological, neurological, and cardiac population with a greater emphasis on treating patients suffering from cancer and stroke. However, further RCTs must consider large sample sizes and more standardized trials to achieve greater efficacy.