Effects of concurrent inspiratory and expiratory muscle training on respiratory and exercise performance in competitive swimmers

Abstract

The efficiency of the respiratory system presents significant limitations on the body's ability to perform exercise due to the effects of the increased work of breathing, respiratory muscle fatigue, and dyspnoea. Respiratory muscle training is an intervention that may be able to address these limitations, but the impact of respiratory muscle training on exercise performance remains controversial. Therefore, in this study we evaluated the effects of a 12-week (10 sessions week(-1)) concurrent inspiratory and expiratory muscle training (CRMT) program in 34 adolescent competitive swimmers. The CRMT program consisted of 6 weeks during which the experimental group (E, n = 17) performed CRMT and the sham group (S, n = 17) performed sham CRMT, followed by 6 weeks when the E and S groups performed CRMT of differing intensities. CRMT training resulted in a significant improvement in forced inspiratory volume in 1 s (FIV1.0) (P = 0.050) and forced expiratory volume in 1 s (FEV1.0) (P = 0.045) in the E group, which exceeded the S group's results. Significant improvements in pulmonary function, breathing power, and chemoreflex ventilation threshold were observed in both groups, and there was a trend toward an improvement in swimming critical speed after 12 weeks of training (P = 0.08). We concluded that although swim training results in attenuation of the ventilatory response to hypercapnia and in improvements in pulmonary function and sustainable breathing power, supplemental respiratory muscle training has no additional effect except on dynamic pulmonary function variables.

Pulmonary adaptations to swim and inspiratory muscle training

“…The present study is in agreement with prior studies (Clanton et al 1987;Wells et al 2005) showing inspiratory muscle strength increases as a result of competitive swim training. In addition, the work per breath derived from the SMIP power curve (joules) increased following the 12 week swim conditioning period.…”

“…These results conflict with those reported for subjects engaged in IMT but without swim training. Similarly, Wells et al (Wells et al 2005) recently demonstrated in adolescent competitive swimmers that 12 weeks of swim training was as effective as swim training plus pressure-threshold respiratory muscle training in eliciting improvements in respiratory muscle strength.…”

“…While several studies have shown that IMT can improve exercise performance in a variety of sports (McConnell and Romer 2004), only two studies to date have assessed the impact of IMT on swim performance. Wells and coworkers (Wells et al 2005) have shown that 12 weeks of CRMT can increase critical swimming speed in female, but not male, adolescent competitive swimmers, whereas Wylegala et al (Wylegala et al 2007) recently demonstrated that 4 weeks of respiratory muscle training improved swimming endurance in scuba divers. Interestingly, research on competitive Masters Swimmers has shown that a single 200 m freestyle swim corresponding to 90-95% of race pace was sufficient to induce inspiratory muscle fatigue (IMF) (Lomax and McConnell 2003).…”

Special training of inspiratory muscles in fitness activities and exercise capacity in young women

“…The anomalous respiratory characteristics of competitive swimmers have been suggested to be due to the extraordinarily advanced respiratory muscle work [35]. All swimmers, not only elite individuals, appear to be a special group of athletes with lung function greater than predicted and better than in other endurance athletes [18,36].…”

The Effect of Expiratory Muscle Training on Pulmonary Function in Normal Subjects

“…S u b s e q u e n t s t u d i e s h a v e s i n c e documented the efficacy of IMT [6][7][8][9][10][11] , and the American Thoracic Society and European Respiratory Society 2) issued a statement that, "IMT could be considered as adjunctive therapy in pulmonary rehabilitation, primarily with suspected or proven respiratory muscle weakness." Studies have shown that expiratory muscle training (EMT) increases maximal expiratory muscle pressure (PE max ), improves pulmonary function, ventilation function and exercise capability and alleviates respiratory distress caused by inspiratory load, activities of daily living or exercise in patients with COPD 12,13) , healthy individuals 10,[14][15][16][17][18][19] , multiple sclerosis (MS) patients [20][21][22] , myasthenia gravis (MG) patients 23) , neuromuscular disease (NMD) patients 24,25) , patients with tetraplegia caused by spinal cord injury 26,27) and Parkinson's disease patients 28,29) . However, some studies have found that: EMT does not increase PE max 30) ; EMT only i m p r o v e s P E m a x , w i t h n o e f f e c t o n o t h e r parameters 31,32) ; and EMT increases PE max , but has no marked impact on other parameters or sufficient evidence is lacking [33][34][35][36] .…”