The effect of inspiratory muscle training on high-intensity, intermittent running performance to exhaustion

Abstract

The effects of inspiratory muscle (IM) training on maximal 20 m shuttle run performance (Ex) during Yo-Yo intermittent recovery test and on the physiological and perceptual responses to the running test were examined. Thirty men were randomly allocated to 1 of 3 groups. The experimental group underwent a 6 week pressure threshold IM training program by performing 30 inspiratory efforts twice daily, 6 d/week, against a load equivalent to 50% maximal static inspiratory pressure. The placebo group performed the same training procedure but with a minimal inspiratory load. The control group received no training. In post-intervention assessments, IM function was enhanced by >30% in the experimental group. The Ex was improved by 16.3% +/- 3.9%, while the rate of increase in intensity of breathlessness (RPB/4i) was reduced by 11.0% +/- 6.2%. Further, the whole-body metabolic stress reflected by the accumulations of plasma ammonia, uric acid, and blood lactate during the Yo-Yo test at the same absolute intensity was attenuated. For the control and placebo groups, no significant change in these variables was observed. In comparison with previous observations that the reduced RPB/4i resulting from IM warm-up was the major reason for improved Ex, the reduced RPB/4i resulting from the IM training program was lower despite the greater enhancement of IM function, whereas improvement in Ex was similar. Such findings suggest that although both IM training and warm-up improve the tolerance of intense intermittent exercise, the underlying mechanisms may be different.

“Functional” Inspiratory and Core Muscle Training Enhances Running Performance and Economy

“…As expected, following the IMT, the global IM function of both groups improved significantly. For example, P 0 , increased by an average of 23%, which is similar to changes observed using identical IMT in previous randomised, placebocontrolled trials (21,25). Global CM function, as assessed by the SEPT, also improved in response to IMT, and the change was correlated with the improvement in P 0 .…”

“…In a previous study we have demonstrated that the response to a similar treadmill interval training is enhanced by a preceding period of IMT (26). Moreover, the improved breathing pattern, post-exercise P 0 , and RPB in the post-intervention ISO trial suggested that the enhanced IM function resulting from the IMT might have alleviated the IM fatigue and breathing effort during the running exercise, and, contributed to the enhancement of the exercise performance (25). Given that our combination of interval training, preceded by IMT, has already been shown to maximise the outcome of interval training, it is all the more impressive that the addition of CM/IM improved performance still further.…”

Inspiratory muscle warm-up does not improve cycling time-trial performance

“…Interestingly, in two separate studies Tong et al (Tong and Fu. 2006;Tong et al 2008) report a two-fold greater reduction in dyspnoea during the Yo-Yo test after an IMW (-15 22%) compared to 6-weeks inspiratory muscle training (-11%), despite a much smaller increase in MIP after IMW (9 vs. 32%). Comparable improvements in Yo-Yo test running performance were also observed following an IMW (13-19%) and inspiratory muscle training (16%).…”

Changes in breathing pattern and cycling efficiency as a result of training with added respiratory dead space volume

“…In order to improve the efficiency of the gas exchange system and respiratory muscles, techniques such as specific inspiratory or expiratory muscle training or hyperpnoea training have been introduced [9][10][11][12]. Several authors reported that these methods improve breathing efficiency by increasing tidal volume while decreasing respiratory rhythm, resulting in a decrease in submaximal and an increase in maximal ventilation efficiency [9,13,14].…”

“…Several authors reported that these methods improve breathing efficiency by increasing tidal volume while decreasing respiratory rhythm, resulting in a decrease in submaximal and an increase in maximal ventilation efficiency [9,13,14]. Furthermore, increased respiratory muscle strength following inspiratory training may contribute to a reduction in relative tension during submaximal exercise [14,15].…”