<![CDATA[Background: Emergency department (ED) nurses must respond quickly and make accurate clinical decisions in life-threatening situations. Although technical skills and experience are known to influence emergency performance, the role of cardiorespiratory fitness has received limited attention, especially among Indonesian emergency nurses. Purpose: To determine the relationship between cardiorespiratory fitness, response time, and clinical decision-making performance among ED nurses. Method: This cross-sectional correlational study included all 28 ED nurses at Jember Klinik Hospital using total sampling. Cardiorespiratory fitness was measured with the Harvard Step Test and estimated VO₂max. Response time was assessed during a standardized in-hospital cardiac arrest simulation as the interval from scenario completion to the first chest compression. Clinical decision-making performance was evaluated using a standardized vignette based on the American Heart Association 2020 cardiac arrest algorithm. Spearman rank correlation was used, with p < 0.05 considered significant. Results: Most nurses had good cardiorespiratory fitness (42.9%), optimal response time (53.6%), and good clinical decision-making performance (50.0%). Cardiorespiratory fitness was significantly associated with faster response time (r = –0.612; p = 0.001), indicating that fitter nurses initiated emergency actions more rapidly. A significant positive association was also found between cardiorespiratory fitness and clinical decision-making performance (r = 0.584; p = 0.001), suggesting that higher fitness levels were linked to better performance during the cardiac arrest simulation. Conclusion: Cardiorespiratory fitness was significantly associated with faster emergency response and better clinical decision-making performance among ED nurses. These findings suggest that fitness assessment and structured physical conditioning programs should be considered in occupational health and professional development strategies to strengthen emergency care quality and patient safety.]]>
