Cardiovascular and metabolic responses to on-water upwind sailing in optimist sailors

PURPOSE: This study aimed to explore the cardiovascular and metabolic responses of 9 Optimist sailors (12.7 yy ± 0.8; 153 cm ± 9; 41 kg ± 6; sailing career: 6.2 yy±1, peak oxygen uptake (VO2peak): 50.5 mL min-1 kg-1 ± 4.5) during on-water upwind sailing with various wind intensities (W). METHODS: In a laboratory session, we measured VO2peak, Qpeak, MAPpeak and fHpeak using a progressive cycle ramp protocol. Steady state VO2, Q, MAP and fH at 4 submaximal workloads were also determined. During two on-water upwind sailing tests (constant course and with tacks), W,Q, MAP and fH were measured for 15 minutes. VO2 on-water was estimated on the basis of steady state fH measured on water and of the individual ΔVO2/ΔfH relationship obtained in the laboratory. RESULTS: VO2, fH and Q expressed as per cent of the corresponding peak values were linearly related with W; exercise intensity during on-water sailing corresponded to 46-48 % of VO2peak. MAP and total vascular peripheral resistance (TPR=MAP/Q) were larger (P < 0.005) during on-water tests (+ 39 % and + 50 %, respectively) than during cycling and they were correlated with W. These responses were responsible for larger values of the double (DP) and triple (TP) products of the heart during sailing than during cycling (P < 0.005) (+37 % and +32%, respectively). CONCLUSIONS: These data indicate that the cardiovascular system was particularly stressed during upwind sailing even though the exercise intensity of this activity was not particularly high