Reliability of novel diagnostic protocols for metabolic performance determinants in swimming

OBJECTIVES: While reliable performance diagnostics are crucial for guiding training and detecting small changes in swimming performance, the reliability of existing protocols remains insufficiently evaluated. DESIGN: Test-retest study. METHODS: ], alongside corresponding heart rate [HR]) on three separate days (within 3 weeks). Reliability and agreement were examined using (among others) intraclass correlation coefficient (ICC 2,1), typical error (TE), and TE to smallest worthwhile change (SWC) ratio, indicating sensitivity. RESULTS: showed excellent reliability (ICC: 0.971-0.990, TE: 0.8-1.4%) with adequate sensitivity (TE/SWC: 0.60-1.14), whereas HR measures were less reliable (ICC: 0.828-0.951, TE: 1.2-3.5%) and insufficiently sensitive (TE/SWC ≥ 1.60). CONCLUSIONS: and HR. The 20-s sprint requires methodological refinement before practical application.