Comparison Of Affective, Perceptual, And Heart Rate Responses To Self-paced Treadmill Versus Trail Running

Abstract

The biophilia hypothesis describes the innate tendency of humans to seek connections with nature and living systems. Therefore, exercise in nature may allow more positive affective responses (AR) compared to exercise indoors, which may affect preferred intensity and ratings of perceived exertion (RPE) during exercise. PURPOSE: To compare AR, RPE, heart rate (HR), and exercise time between self-paced indoor treadmill running and outdoor trail running conditions. METHODS: Ten college-aged men and women were recruited for two self-paced exercise sessions performed in a random, counterbalanced order. The indoor exercise was performed on a treadmill in the laboratory without view of nature. The outdoor exercise was performed on a wooded trail, immersed in nature. For both sessions, the first 0.25 mi was a self-paced walking warm-up, the next 1.5 mi was self-paced running, and the last 0.25 mi was a self-paced walking cool-down. AR (Feeling Scale), RPE (Adult OMNI Walk/Run Scale), and HR (Mio Alpha) were measured at the middle and end of the 1.5 mi of running. AR, RPE, and HR were compared between sessions using mixed-model ANOVA. Total exercise time was compared between sessions using a paired-samples t-test. RESULTS: A significant main effect indicated higher average AR during trail running compared to the treadmill (2.4 ± 0.6 v 0.6 ± 0.6, p < 0.05). A significant interaction effect (p < 0.05) indicated AR increased during trail running (2.2 ± 0.5 to 2.6 ± 0.6) yet decreased during treadmill running (1.0 ± 0.5 to 0.3 ± 0.5). Although average RPE values were similar between conditions, a significant interaction effect (p < 0.05) indicated that RPE was stable during trail running (5.4 ± 1.2 to 5.3 ± 1.6) yet increased significantly during treadmill running (4.7 ± 1.3 to 6.2 ± 1.0). HR increased similarly during both exercise sessions, yet exercise time was significantly less for trail compared to treadmill running (17.8 ± 3.5 min v 22.1 ± 4.5 min). CONCLUSIONS: For indoor treadmill running, RPE increased with HR as expected, yet AR declined. Outdoor trail running, although with similar increasing HR, produced stable RPE and increased AR. These results indicate that self-paced running immersed in nature can have more positive effects on mood while providing the same physiological benefit as indoor treadmill running.