Abstract des Autors

Objectives: To assess oxygen uptake (VO2), blood lactate concentration ([La]b), and heart rate (HR) response during indoor and outdoor sport climbing. Methods: Seven climbers aged 25(SE 1) years, with a personal best ascent without preview or fall (on sight) ranging from 6b to 7a were assessed using an indoor vertical treadmill with artificial rock hand/foot holds and a discontinuous protocol with climbing velocity incremented until voluntary fatigue. On a separate occasion the subjects performed a 23.4 m outdoor rock climb graded 5c and taking 7 min 36 s (SE 33 s) to complete. Cardiorespiratory parameters were measured using a telemetry system and [La]b collected at rest and after climbing. Results: Indoor climbing elicited a peak oxygen uptake (VO2climb-peak) and peak HR (HRpeak) of 43.8(SE 2.2) ml/kg/min and 190(SE 4) bpm, respectively and increased blood lactate concentration [La]b from 1.4(0.1) to 10.2(0.6) mmol/l (p<0.05). During outdoor climbing VO2 and HR increased to about 75% and 83% of VO2climb-peak and HRpeak, respectively. [La]b increased from 1.3(0.1) at rest to 4.5 mmol/l (p<0.05) at 2 min 32 s (8 s) after completion of the climb. Conclusions: The results suggest that for elite climbers outdoor sport rock climbs of five to 10 minutes' duration and moderate difficulty require a significant portion of the VO2climb-peak. The higher HR and VO2 for outdoor climbing and the increased [La]b could be the result of repeated isometric contractions, particularly from the arm and forearm muscles. Verf.-Referat