Abstract

Given that the popularity of indoor climbing exceeds that of outdoor climbing, health professionals need a better understanding of how these indoor climbing activities can be used to prescribe exercise. The primary goal of this study was to characterize both cardiovascular and metabolic responses of motorized treadmill climbing with respect to thresholds for heart rate as a percent of maximum (%HR) and metabolic equivalents (METs). Additionally, this study used these data to generate MET and energy expenditure (EE) prediction equations for prescription purposes. Methods: Twenty non-competitive recreational climbers (16 men; 4 women) were recruited to climb six combinations of “slow” and “fast” climbing speed (4.6-9.1 m/min) across three treadmill grades: vertical (90°), overhang or negative incline (85-80°), positive incline (95-100°). A portable metabolic system was worn by climbers during testing to measure HR and oxygen uptake (VO2), the latter of which was converted to EE and METs using standard formulae. Mean HR% and MET values were compared to intensity thresholds (65%, or 3 and 6 METs) using one-sample t-tests, while standard multiple regression techniques were used to predict EE and METs from a pool of variables (climbing treadmill speed and grade, body mass, gender. Results: HR% (70.0-85.4%) was >65% at all test conditions (P<0.01) and mean MET values exceeded the 3-MET threshold and was ≥6-MET threshold at all conditions (6.0-8.5 METs; P<0.01). Multiple prediction equations for both EE (R2=0.81; SEE=±0.83 kcals/min; P<0.001) and METs (R2=0.73; SEE=±0.6 METs; P<0.001) included speed, grade, and gender. Conclusions: The vigorous metabolic intensity for motorized treadmill climbing (≥6 METs) in this study was clearly sufficient to promote positive health and metabolic fitness in healthy adults. In addition, health professionals can use the EE and MET prediction equations to prescribe specific motorized treadmill climbing intensities to clients, as well as generate climbing-specific testing protocols.

Keywords

Energy Expenditure, Metabolic Equivalent, Heart Rate, Exercise Prescription, Rock Climbing,

References

  1. The Outdoor Foundation, Outdoor Participation Report 2018, The Outdoor Foundation: Washington, D.C. USA (2018).
  2. L.V. Giles, E.C. Rhodes, J.E. Taunton, The physiology of rock climbing, Sports Medicine, 36 (2006) 529-545.
  3. S. Grant, V. Hynes, A. Whittaker, T. Aitchison, Anthropometric, strength, endurance and flexibility characteristics of elite and recreational climbers, Journal of Sports Science, 14 (1996) 301-309.
  4. J.T. Rohrbough, M.K. Mudge, R.C. Schilling, Overuse injuries in the elite rock climber, Medicine and Science in Sports and Exercise, 32 (2000) 1369-1372.
  5. A.W. Sheel, Physiology of sport rock climbing, British Journal of Sports Medicine, 38 (2004) 355-359.
  6. P.B. Watts, Physiology of difficult rock climbing, European Journal of Applied Physiology, 91 (2004) 361-372.
  7. US Department of Health and Human Services, (2008) Physical Activity Guidelines for Americans.
  8. Global Recommendations on Physical Activity for Health, (2010) World Health Organization, Geneva, Switzerland.
  9. Rodio, L. Fattorini, A. Rosponi, F.M. Quattrini, M. Mrachetti, Physiological adaptation in noncompetitive rock climbers: Good for aerobic fitness? Journal of Strength and Conditioning Research, 22 (2008) 359-364.
  10. ACSM’s Guidelines for Exercise Testing and Prescription (9th edition), The Journal of the Canadian Chiropractic Association, 58 (2014) 328.
  11. L. Wideman, N.M. Stoudemire, K.A. Pass, C.L. McGinnes, G.A. Gaesser, A. Weltman, Assessment of the AeroSport TEEM 100 portable metabolic measurement system, Medicine and Science in Sports and Exercise, 28 (1996) 509-515.
  12. W.B. Weir, New methods for calculating metabolic rate with special reference to protein metabolism, The Journal of Physiology, 109 (1949) 1-9.
  13. Alan C. Lacy, Douglas N. Hastad, Measurement for Evaluation in Physical Education and Exercise Science (5th ed.) Benjamin Cummings, WCB Brown and Benchmark, (1995) 45-72.
  14. D.G. Kleinbaum, L.L. Kupper, K.E. Muller. Applied Regression Analysis and Other Multivariable Methods (2nd ed.), CA: Duxbury Press, Belmon, (1988) 124-296.
  15. D.P. Heil, P.S. Freedson, L.E. Ahlquist, J. Price, J.M. Rippe, Non-exercise regression models to estimate peak oxygen consumption, Medicine and Science in Sports and Exercise, 27 (1995) 599-606.
  16. D.B. Holiday, J.E. Ballard, B.C. McKeown, PRESSrelated statistics: Regression tools for crossvalidation and case diagnostics, Medicine and Science in Sports and Exercise, 27 (1995) 612- 620.
  17. J. Lee, K.S. Chia, H.P. Lee, Regression analysis of biomedical research data based on a repeated measured or cluster sample, Annals of the Academy of Medicine, Singapore, 25 (1996) 129- 133.
  18. J. Booth, F. Marino, C. Hill, T. Gwinn, Energy cost of sport rock climbing in elite performers, British Journal of Sports Medicine, 33 (1999) 14- 18.
  19. C.M. Mermier, R.A. Robergs, S.M. McMinn, V.H. Heyward, Energy expenditure and physiological responses during indoor rock climbing, British Journal of Sports Medicine, 31 (1997) 224-228.
  20. P.B. Watts, K.M. Drobish, Physiological responses to simulated rock climbing at different angles, Medicine and Science in Sports and Exercise, 30 (1998) 1118-1122.
  21. D.P. Heil, The pressor response to submaximal cycle ergometry while using aerodynamic handlebars, International Journal of Sports Medicine, 18 (1997) 1-7.
  22. Kilbom, J. Persson, Cardiovascular response to combined dynamic and static exercise, Circulation Research (Supplement 1), 48 (1981) 193-197.
  23. P.B. Watts, D.T. Martin, M.H. Schmeling, B.C. Silta, A.G. Watts, Exertional intensities and energy requirements of technical mountaineering at moderate altitude, Journal of Sports Medicine and Physical Fitness, 30 (1990) 365-376