<b>Association Between Habitual Caffeine Intake and Delayed Onset Muscle Soreness Among Recreationally Active Females</b>

Background: Delayed onset muscle soreness (DOMS) is a common, self-limiting pain syndrome following unfamiliar or intense exercise and may influence training adherence in recreationally active females; caffeine is widely consumed and may modulate post-exercise pain perception through adenosine receptor antagonism. Objective: To determine the association between habitual caffeine intake and DOMS severity and to evaluate the relationship between physical activity level and DOMS severity among recreationally active females. Methods: A cross-sectional observational study was conducted among 126 females (18–25 years) recruited from three fitness facilities in Lahore, Pakistan. Habitual caffeine intake was assessed using the Caffeine Consumption Questionnaire and categorized as low (<100 mg/day) or moderate (100–300 mg/day). DOMS severity was measured using a Likert-type muscle soreness scale (no, mild, moderate, severe). Physical activity level was classified using the International Physical Activity Questionnaire (low, moderate, high). Associations were tested using chi-square analyses (α = 0.05), with effect sizes reported as Cramér’s V. Results: Mean age was 21.02 ± 2.02 years. DOMS was reported by 82/126 (65.1%), most commonly moderate (27.8%) and mild (23.0%). Caffeine intake was significantly associated with DOMS severity (χ² = 18.47, df = 3, p = 0.001; Cramér’s V = 0.38), with severe soreness more frequent in low versus moderate caffeine consumers (24.6% vs 4.6%). Physical activity level was associated with DOMS severity (χ² = 13.21, df = 6, p = 0.038; Cramér’s V = 0.23). Conclusion: Moderate habitual caffeine intake and higher physical activity levels were associated with lower DOMS severity in recreationally active females.