Background: Rapid urbanization, accompanied by increasing pollution and psychological stress, has intensified sedentary lifestyles that are inconsistent with human evolutionary biology. Green exercise enhances individuals’ engagement with natural environments and promotes participation in physical activity. The combination of exercise and exposure to natural settings may produce synergistic effects on key physiological indices, including blood pressure, heart rate, and heart rate variability. Therefore, this study aimed to investigate the effects of a prolonged mountain-based green exercise program on blood pressure, heart rate, and heart rate variability in young adults aged 20–30 years.
Methods: In this study, twenty volunteers (10 females and 10 males) were recruited from students at the University of Tehran. Participants had a mean age of 24.9 ± 2.99 years, body mass of 64.1 ± 9.87 kg, height of 169.48 ± 7.11 cm, and body mass index of 22.5 ± 3.01 kg/m². A hiking route comprising 43 waypoints was designed, spanning elevations from 2140 to 3015 m and covering a total distance of 11.73 km. Data were analyzed using analysis of covariance (ANCOVA).
Results: Participants completed a total ascent of 880 m and descent of 889 m. Blood pressure, heart rate, and heart rate variability were measured before and after the hiking session. The hiking bout lasted 7 hours and was performed at moderate intensity. Prolonged single-day hiking significantly increased heart rate and decreased heart rate variability, while changes in blood pressure were not statistically significant.
Conclusions: Prolonged mountain hiking within a single day elicits marked acute cardiovascular responses, characterized by elevated heart rate and reduced heart rate variability without significant alterations in blood pressure. These findings highlight the critical role of exercise duration in green exercise physiology. Sustained sympathetic activation and inter-individual variability may partly explain the observed responses.