Effect Of Inspiratory Muscle Warm-Up On Badminton Footwork Performance

Purpose: The effects of inspiratory muscle (IM) warm-up on IM function and on the maximum distance covered in a subsequent incremental badminton-footwork test were examined. Methods: Ten male badminton players were recruited to perform identical tests in three different trials randomly. The control trial was without IM warm-up while the placebo and experimental trials were with IM warm-up by performing two sets of 30 breaths with an inspiratory pressure-threshold load equivalent to 15% (PLA) and 40% (IMW) maximum inspiratory mouth pressure, respectively. Results: By comparison with control values in IMW, the IM function revealed by the maximal inspiratory pressure at zero flow (P0) and maximal rate of P0 development (MRPD) were increased (P<0.05). The FWmax was enhanced 6.8±3.7% (P<0.05) while the slope of the linear relationship of the increase in the rating of perceived breathlessness for every minute (RPB/min) was reduced (P<0.05). Reduction in blood lactate ([La-]b) accumulation was observed when the test duration was identical to that of control trial (P<0.05). In PLA, no parameter was changed from control. For the changes (?) in parameters in IMW (n=10), negative correlations were found between ?P0 and ?RPB/min (r=-0.76), ?MRPD and ?RPB/min (r=-0.69), ?RPB/min and ?FWmax (r=-0.77), but not between ?[La-]b accumulation and ?FWmax (P>0.05) Conclusion: Such findings suggest that the specific IM warm-up improved footwork performance in the subsequent maximum incremental badminton-footwork test. The improved footwork was partly attributable to the reduced breathless sensation resulting from the enhanced IM function, while the contribution of the concomitant reduction in [La-]b accumulation was relatively minor.