The Effect of 6 Weeks of Inspiratory Muscle Training (IMT) on Swimming Speed

Previous research has shown that inspiratory muscle training can improve endurance performance of athletes in a range of sports. However, few studies have tried to investigate the effect of respiratory training on swimmers. Due to the specificcharacteristics of the respiratory system in swimmers, this study examined the effect ofinspiratory muscle training on speed performance of swimmers. 16 female members ofthe swimming team of Kermanshah province voluntarily participated in this study andrandomly divided into sham training group (mean age 10.75±1.98 yr, height140.68±14.7 cm, weight 32.17±10.61 kg) and experimental group (mean age10.75±2.18 yr, height 143.68±13.62 cm, weight 36.6±9.01 kg) and trained for 6 weeks(3 sessions per week, 30 breaths per session). Training intensity in the experimentalgroup was equal to 5(severe) and in the sham group was equal to 1(very slight) inmodified Borg scale. Before and after the training protocol, 25, 50 and 100m front crawl swimming tests were performed. T test was used to analyze data by SPSS software (P<0.05). The findings showed that after inspiratory muscle training, performance of experimental group improved significantly in the 25m swimming test (P<0.05) while changes were not significant in 50 and 100m tests. This study demonstrated that physiological adaptations that occur after IMT training in respiratory muscles can explain the significant improvement in 25m swimming test in the experimental group. But 50 and 100m swimming tests did not show any significant changes. It may be noted that adaptations involved could not influence more than 25m. The mechanisms influencing these results are not yet known clearly.