Effects of Inspiratory Muscle Training on Physiological Performance Variables in Women's Handball

Inspiratory muscle training (IMT) has been used in different sports, although there is no consensus on its benefits. We investigated the effects of eight weeks of IMT in women's handball. Twenty-four players were randomly distributed into experimental (EXP; n = 13) and control (CON; n = 11) groups. Only the EXP group performed IMT using the POWERBreathe device, following indications of the manufacturers. Before and after the intervention, spirometric variables were evaluated at rest and during a graded test using direct analysis of respiratory gases. Perception of exertion at submaximal intensity was also determined. No significant differences were observed post- vs. pre-intervention (p ≥ 0.05) regarding forced vital capacity (FVC), forced expiratory volume in the 1st second (VEF1), FVC/VEF1, maximal expiratory flow at 50% of FVC or peak inspiratory flow. Post-intervention, only the CON group increased their absolute and relative VO2max (2.1 ± 0.2 L/min pre vs. 2.2 ± 0.3 L/min post; 33.6 ± 3.6 ml/kg∙min pre vs. 34.5 ± 3.2 ml/kg∙min post, respectively). No significant improvements (p ≥ 0.05) were observed in VO2 associated with ventilatory threshold 1 (VT1), nor in the intensity associated with VO2max and VT1. However, there was a tendency for the mentioned variables to decrease in the CON group, while in the EXP group the trend was to maintain or increase previous values. IMT did not determine an improvement in the perception of exertion at submaximal intensity. The use of POWERBreathe, as described in the present study, is feasible in terms of time and effort, although its benefits may not be significant.

Effects of respiratory muscle training in soccer players: a systematic review with a meta-analysis

Respiratory muscle training can improve strength and reduce respiratory muscle fatigue during high-intensity exercise. Little is known about the existing evidence in soccer players. A systematic review with a meta-analysis was performed to analyse the existing evidence on the effects of respiratory muscle training in soccer players. Two independent researchers reviewed 17 databases until July 2019. Inclusion criteria were controlled clinical trials (randomised or not), soccer players (professional or recreational), females and/or males, and respiratory muscle training compared with simulated or regular training groups. The methodological quality and quality of evidence were evaluated with the Cochrane Collaboration Tool and GRADE score, respectively. Statistical analysis was performed using the integral meta-analysis 3.3.070. Nine studies met the eligibility criteria. The meta-analysis was performed for eight variables related to respiratory muscle function, lung function and sports performance. Respiratory muscle training provided a significant improvement compared with simulated or regular training in maximal inspiratory buccal pressure (6 studies, SDM = 0.89; 95 % CI = 0.42, 1.35) and maximum consumption of oxygen (3 studies, SDM = 0.92; 95 % CI = 0.24; 1.61). No significant improvements were observed for other variables. The quality of the evidence was rated as low or very low.

Inspiratory Muscle Training in Intermittent Sports Modalities: A Systematic Review

The fatigue of the respiratory muscles causes the so-called metabolic reflex or metaboreflex, resulting in vasoconstriction of the blood vessels in the peripheral muscles, which leads to a decrease in respiratory performance. Training the respiratory muscles is a possible solution to avoid this type of impairment in intermittent sports. The objective of this systematic review was to evaluate the results obtained with inspiratory muscle training (IMT) in intermittent sports modalities, intending to determine whether its implementation would be adequate and useful in intermittent sports. A search in the Web of Science (WOS) and Scopus databases was conducted, following the Preferred Reporting Elements for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The methodological quality of the articles was assessed using the PEDro (Physiotherapy Evidence Database) scale. In conclusion, the introduction of specific devices of IMT seems to be a suitable method to improve performance in intermittent sports, mainly due to a reduction of the metaboreflex, fatigue sensation, and dyspnea. The ideal protocol would consist of a combination of acute and chronic treatment, and, even if IMT is done daily, the duration will not exceed one hour per week.