Background: Reports indicate that top-class compared to less welltrained sailors demonstrate greater hiking abilities by sustaining greater fractions of their maximum quadriceps muscle strength. Aim: To investigate the extent to which central hemodynamic and local muscle capacities for oxygen transport and extraction are superior in highly-ranked compared to less well-ranked sailors. Methods: Six highly-ranked and six club sailors performed 3 successive 2-min hiking bouts followed by a 4th bout to exhaustion. Vastus lateralis muscle deoxygenated hemoglobin concentration (an index of local muscle oxygen extraction) was measured by Near- Infrared Spectroscopy, whereas cardiac output was determined using impedance cardiography. Results: Highly-ranked compared to club sailors demonstrated significantly prolonged hiking endurance time (298 ± 10 versus 201 ± 7 sec). Mean arterial blood pressure and quadriceps muscle oxygen extraction, were greater in highly-ranked as compared to club sailors throughout the three successive hiking efforts. At the limit of tolerance of the final hiking bout, cardiac output, stroke volume, and systemic vascular conductance were significantly greater in highly-ranked (26.1 ± 1.2 l/min; 180 ± 10 ml/beat; 179 ± 5 ml/min/mmHg, respectively) compared to club sailors (21.7 ± 1.1 l/min; 131 ± 7 ml/beat; 160± 7 ml/min/mmHg, respectively). At the end of the final bout, highly ranked compared to club sailors exhibited significantly greater quadriceps muscle deoxygenated hemoglobin concentration (23.2 ± 2.7 µmol/l versus 15.5 ± 1.6 µmol/l, respectively). Conclusions: Highly-ranked sailors exhibit superior cardiovascular and quadriceps muscle oxygen utilization capacities. Such superior central and peripheral muscle capacities for oxygen transport and utilization may explain why highly-ranked sailors demonstrate advanced hiking ability.
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