Estimativa do custo energético e contribui??o das diferentes vias metabólicas na canoagem de velocidade

摘要

The performance of the speed kayaking depends on the organism capacity of regenerating ATP in large amounts and high rates from different metabolic pathways. Thus, the objective of the present study was to combine two bioenergetic models, the first a generic one, called critical power, and the other specific for kayaking, proposed by Zamparo et al. (1999), in the attempt of producing estimations of aerobic and anaerobic fitness for this modality, as well as establishing non-invasive estimations of the contribution of aerobic and anaerobic systems for different distances performed. In that purpose, 11 male kayaking athletes (16.0 ± 1.2 years; 174.0 ± 2.4 cm; 65.2 ± 4.4 kg), performed different distances (500, 1,000 and 1,790 m), at the maximal speed as possible in kayaks type K-1 in a calm water lake. The informations obtained were initially converted into work generated quantity (kJ) and internal power (W). The estimated individual values were afterwards applied to three predictive equations of critical power (PCrit) and anaerobic work capacity (CTAnaer). Finally, the values produced were transformed into oxygen equivalence units for the estimation of the aerobic contribution (O2 equivalence for PCrit x time required to perform the distance) and anaerobic contribution (O2 equivalence for CTAnaer x time required to perform the distance) at the different distances. The relative anaerobic contribution found for the different distances analyzed (500, 1,000 and 1,790 m) was of 60.6; 78.6 and 89.4%, respectively. The results found corroborate the information previously produced by other investigations, suggesting that the procedures adopted in this study may provide reliable estimations on the participation of the energetic pathways on the kayaking performance.