M Fisch, K Czeczor, Mirjam Limmer, Till Krusche, Petra Platen

Publikation: Beitrag in Buch/Bericht/KonferenzbandKonferenzbeitrag - Abstract in KonferenzbandForschungBegutachtung


Introduction The step test (ST) is a frequently applied test in performance and functional diagnostics, easy to handle, low in equipment, and especially useful for testing in the field during mountaineering. The aim of this study is to validate a modified Canadian Aerobic Fitness test (mCAFT) on a commercially available stepper for the determination of VO[2max] Methods 22 subjects (9f, 13m, 26.2±3.3 yrs, 176.0±8.5 cm, 72.2±11.9 kg) performed a Bruce protocol on a treadmill (gold standard, GS)) for the determination of VO[2max], and three incremental ST (step frequency 66, 84, 102, 114, 132, 144 bpm, and, after increasing step height by 5cm: 118, 132 bpm, each step 5 min with 1 min rest between stages), with spirometry, heart rate and lactate analysis until exhaustion (two tests with nearly 90° knee angle (ST[90], ST[90r] for test-retest-reliability), and one test with an additional top (+5cm, ST[90+1]) in randomized order). Parameters included VO[2max], heart rates (HR), blood lactate concentration (La), and maximum step frequency (ST[fmax]). Results Both ST resulted in similar values for Hf[max] and La[max], while VO[2max] was higher and ST[fmax] was lower in ST[90+1] (192.2±7.9 vs. 191.9±9.3 bpm; 7.8±2.1 vs. 8.5±1.9 mmol/l; 47.4±6.0 vs. 47.1±6.5 ml/min/kg; 142.1±12.8 vs. 130.0±13.5 bpm). Test-Retest reliability was highly significant for VO[2max], Hf[max], La[max], and ST[fmax] (ICC-values: VO[2max]: 0.948, Hf[max]: 0.907, La[max]: 0.826, ST[fmax]: 0.963). ST90 underestimated VO[2max] compared to GS (47.4±6.0 vs. 54.5±8.3 ml/min/kg, p<0.01), however nearly all subjects remained within the 1sdrange around the mean difference of 7.1 ml/min/kg in the Bland-Altman plot. Discussion Concerning the high validity and test-retestreliability, the modified step test with 90° knee angle might be used for the determination of VO[2max] under field conditions in the mountains where no other technical equipment is available. References Bruce, R. A.; Kusumi, F. & Hosmer, D. (1973). Maximal oxygen intake and nomographic assessment of functional aerobic impairment in cardiovascular disease. American heart journal, 85 (4), 546- 562.
TitelBOOK OF ABSTRACTS : 19th annual Congress of the EUROPEAN COLLEGE OF SPORT SCIENCE 2nd - 5th July 2014, Amsterdam – The Netherlands
PublikationsstatusVeröffentlicht - 2014