Cardiovascular Response to Exercise with and Without Alcohol Consumption: Evidence of an Interaction Between Distance Covered and Perceived Exertion

Background: Acute alcohol consumption may interfere with the dynamics between internal and external load during exercise, potentially attenuating cardiovascular responses. Objective: This study investigated the association between distance covered during a running test and mean heart rate, while examining the moderating role of the rating of perceived exertion (RPE) under conditions with and without acute alcohol ingestion. Methods: This crossover experimental study included 12 physically active male university students (23.7 ± 3.7 years). Participants completed two intermittent running sessions (control and alcohol conditions), separated by ≥48 h. In the alcohol condition, participants consumed 0.4 g of ethanol/kg of body mass. Heart rate was continuously monitored using a Polar RCX5 monitor, and total distance covered and RPE (Borg 6–20 scale) were assessed immediately after test completion. Analyses included paired comparisons, Pearson correlations, and linear regression models with interaction terms. Results: No significant associations between variables were observed in the control condition. With alcohol consumption, distance covered was positively associated with mean heart rate, and RPE significantly moderated this relationship. Conclusions: Acute alcohol ingestion may modify the interaction between external load, perceived exertion, and cardiovascular response during running. These results highlight the importance of integrated monitoring of internal and external load, especially in contexts involving recent alcohol consumption.