High ropes course (HRC) facilities are employed to promote self-esteem, stress management, and problem-solving skills. A small, yet, notable incidence of cardiac events during HRC work suggests that a high stress load is imposed upon the cardiovascular system, however, no previous research has described the nature of such work. The purpose of this study was to observe metabolic and cardiovascular responses during HRC work. Subjects (n = 17; age = 25.1±6.8 yrs) gave informed consent to complete a 5-element sequence on an indoor HRC. Elements included step-swings (SS), swinging tires (ST), a 4-inch balance beam (B1), a vertical cargo net (CN), and a second beam (B2). These elements were positioned in series approximately 20 feet above the floor. Expired air was analyzed continuously using a portable system(AeroSport) and averaged over 20-sec intervals. Heart rate (HR) was recorded via telemetry (Polar). Pre- and post-course blood samples were obtained via finger-prick and analyzed (YSI 1500) for lactate (BLA). Systolic (SBP) and diastolic (DBP) blood pressures were taken via auscultation at orientations prior to each subject's test date and at pre-, mid-, and post-course points during each test session. Mean work time was 11.2±2.9 min. Mean averaged\peak oxygen uptake (VO2), HR, and energy expenditure (EE) were 13.9±2.3\21.6±3.7 ml·kg-1·min-1, 142±16\167±15 b·min-1, and 5.1±0.9\7.7±1.0 kcal·min-1 respectively. In descending order, mean EE was 6.2±1.1, 6.2±0.8, 5.4±1.0, 4.5±0.5, and 4.2±0.5 kcal·min-1 for B2, ST, CN, B1, and SS elements respectively. BLA increased (P<0.05) from 1.9±0.6 pre- to 5.0±1.1 mmol·l-1 post-course. SBP values at pre- (136.7±16.0), mid-(169.8±19.7), and post-course(154.1±19.2) were higher (P<0.05) than the orientation SBP of 126.2±14.7 mmHg. Mid- and post-course SBP means were significantly higher than the pre-course mean. A significant difference was found for DBP between the mid-course (86.3±8.9) vs orientation mean(79.1±6.8). Average work on a HRC can be classified as aerobically moderate, at just over 4 METs with peak periods over 7 METs, with a significant anaerobic contribution. Transient significant elevation in DBP may occur. HRC work does not present an unusually high physiological stress for healthy, physically fit individuals.
Read full abstract