ISSN:
1439-6327
Keywords:
Key words Exercise time to exhaustion
;
Maximal oxygen uptake
;
Accumulated oxygen deficit
;
Percentage anaerobic metabolism
;
Energy demand
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Using 23 elite male athletes (8 cyclists, 7 kayakists, and 8 swimmers), the contribution of the anaerobic energy system to the time to exhaustion (t lim) at the minimal exercise intensity (speed or power) at which maximal oxygen uptake (V˙O2 max) occurs (I V˙O2 max) was assessed by analysing the relationship between the t lim and the accumulated oxygen deficit (AOD). After 10-min warming up at 60% of V˙O2 max, the exercise intensity was increased so that each subject reached his I V˙O2max in 30 s and then continued at that level until he was exhausted. Pre-tests included a continuous incremental test with 2 min steps for determining the I V˙O2max and a series of 5-min submaximal intensities to collect the data that would allow the estimation of the energy expenditure at I V˙O2max . The AOD for the t lim exercise was calculated as the difference between the above estimation and the accumulated oxygen uptake. The mean percentage value of energy expenditure covered by anaerobic metabolism was 15.2 [(SD 6)%, range 8.9–24.1] with significant differences between swimmers and kayakists (16.8% vs 11.5%, P≤0.05) and cyclists and kayakists (16.4% vs 11.5%, P≤0.05). Absolute AOD values ranged from 26.4 ml · kg−1 to 83.6 ml · kg−1 with a mean value of 45.9 (SD 18) ml · kg−1. Considering all the subjects, the t lim was found to have a positive and significant correlation with AOD (r = 0.62, P≤0.05), and a negative and significant correlation with V˙O2 max (r = −0.46, P≤0.05). The data would suggest that the contribution of anaerobic processes during exercise performed at I V˙O2max should not be ignored when t lim is used as a supplementary parameter to evaluate specific adaptation of athletes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004210050207
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