title: Physiological responses to indoor rock-climbing and their relationship to maximal cycle ergometry.
abstract: OBJECTIVE
  To quantify the cardiorespiratory responses to indoor climbing during two increasingly difficult climbs and relate them to whole-body dynamic exercise. It was hypothesized that as climbing difficulty increased, oxygen consumption ([V02] and heart rate would increase, and that climbing would require utilization of a significant fraction of maximal cycling values.
  
  
  METHODS
  Elite competitive sport rock climbers (6 male, 3 female) completed two data collection sessions. The first session was completed at an indoor climbing facility, and the second session was an incremental cycle test to exhaustion. During indoor climbing subjects were randomly assigned to climb two routes designated as "harder" or "easier" based on their previous best climb. Subjects wore a portable metabolic system, which allowed measurement of oxygen consumption [V02], minute ventilation ([V02]E), respiratory exchange ratio (RER), and heart rate. During the second session, maximal values for [V02], [V02]E, RER, and heart rate were determined during an incremental cycle test to exhaustion.
  
  
  RESULTS
  Heart rate and [VO2], expressed as percent of cycling maximum, were significantly higher during harder climbing compared with easier climbing. During harder climbing, %HR(max) was significantly higher than %[V02] (2max) (89.6% vs 51.2%), and during easier climbing, %HR(max) was significantly higher than %[V02] (2max) (66.9% vs 45.3%).
  
  
  CONCLUSIONS
  With increasing levels of climbing difficulty, there is a rise in both heart rate and [V02]. However, there is a disproportional rise in heart rate compared with [V02], which we attribute to the fact that climbing requires the use of intermittent isometric contractions of the arm musculature and the reliance of both anaerobic and aerobic metabolism.
authors.affiliation: School of Human Kinetics, The University of British Columbia, Vancouver, BC, Canada. bill.sheel@ubc.ca
authors.forename: A William
authors.initials: AW
authors.lastname: Sheel
authors.forename: Nicholas
authors.initials: N
authors.lastname: Seddon
authors.forename: Andrew
authors.initials: A
authors.lastname: Knight
authors.forename: Donald C
authors.initials: DC
authors.lastname: McKenzie
authors.forename: Darren E
authors.initials: DE
authors.lastname: R  Warburton
mesh_terms: D000293:Adolescent; D000328:Adult; D004734:Energy Metabolism; D005080:Exercise Test; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D009051:Mountaineering / Q000502:physiology*; D010101:Oxygen Consumption