Influence of Inspiratory Muscle Training of Various Intensities on the Physical Performance of Long-Distance Runners

Effects of extracorporeal diaphragm pacing combined with inspiratory muscle training on respiratory function in people with stroke: a randomized controlled trial

OBJECTIVES

To evaluate the effect of external diaphragmatic pacing (EDP) combined with inspiratory muscle training on respiratory function in post-stroke patients.

METHODS

Patients with stroke were enrolled from the First Affiliated Hospital of Soochow University in China between 2021 and 2022. The patients were randomized into an EDP treatment group (control group) or an EDP treatment plus inspiratory muscle training group (experimental group). Each therapy was administered once a day for 6 days per week. The peak inspiratory flow (PIF), maximal inspiratory pressure (MIP), forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC% ratio, and diaphragm thickness and mobility were measured and compared between the two groups after 4 weeks.

RESULTS

After 4 weeks of intervention, respiratory muscle function indicators including PIF (95% CI: 0.21-1.28, p = 0.008) and MIP (95% CI: 6.92-25.44, p = 0.001) significantly improved in the experimental group. Diaphragmatic thickness also significantly increased in the experimental group (p < 0.05), while diaphragmatic excursion showed no significant difference between the two groups. Additionally, FVC (95% CI: 0.14-1.14, p = 0.013) and FEV1 (95% CI: 0.20-1.06, p = 0.005) demonstrated a significant increase in the experimental group, whereas FEV1/FVC% (95% CI: -0.84 to 9.36, p = 0.099) exhibited no significant group difference.

CONCLUSION

EDP combined with inspiratory muscle training in individuals with stroke provides greater benefits than EDP alone in terms of respiratory function recovery, except for the parameters of diaphragmatic excursion and FEV1/FVC%.

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.

Inspiratory Muscle Training Improves Maximal Inspiratory Pressure Without Increasing Performance in Elite Swimmers

PURPOSE

To analyze the effect of inspiratory muscle training (IMT) on the maximal inspiratory mouth pressure (MIP) and performance of elite swimmers.

METHODS

Eight participants performed a 3000-m swimming test (T-3000), followed by blood lactate measurements at 1 and 5 minutes postexercise.. The testing protocol was carried out before and after 6 weeks of IMT, in which a high-volume IMT group (HV-IMT) (n = 4) performed IMT twice a day-in the morning in a seated position and in the afternoon in a concurrent session of IMT and core muscle training. Also, a low-volume IMT group (LV-IMT) (n = 4) performed IMT in the morning session only.

RESULTS

After the intervention, both groups improved their MIP, HV-IMT (132.75 [27.42] to 156.75 [21.88] cmH2O; P = .010; d = 0.967) and LV-IMT (149.25 [22.82] to 171.50 [23.74] cmH2O; P = .013; d = 0.955), without a significant difference between groups (P = .855). Regarding swimming performance, there were no changes between groups in the T-3000 (P = .472) or lactate removal rate (P = .104).

CONCLUSION

IMT increased inspiratory muscle strength in elite swimmers, but there was no association or meaningful impact on swimming performance.

The Effect of Inspiratory Muscle Training on the Pulmonary Function in Mixed Martial Arts and Kickboxing Athletes

Inspiratory muscle training (IMT) has found its way into athletes’ routine as a promising way of improving pulmonary function in combination with standard training. The objective of the study was to examine the effects of resistive IMT on the pulmonary function variables in athletes of two combat sports, i.e., mixed martial arts (MMA) and kickboxing. Fourteen kickboxing and 12 MMA male athletes qualified for the study. They were randomly assigned into experimental and control groups. While both groups participated in their standard training, the experimental group additionally participated in IMT which consisted of 30 breaths twice a day for 6 weeks. The pulmonary functions were measured at baseline and after 6 weeks of IMT. The addition of IMT to standard training increased significantly the forced expiratory volume in the first second to vital capacity ratio (FEV1/VC), and the maximum voluntary ventilation (MVV) (p < 0.05) with changes of 5.7%, and 28.6%, respectively, in MMA athletes. The kickboxing group showed no significant changes. The interaction of the sport discipline and IMT intervention yielded a strong significant change in the MVV (F(1, 11) = 14.53, p < 0.01), and FEV1/VC (F(1, 11) = 20.67, p < 0.01) to the benefit of MMA athletes in comparison with kickboxing athletes. Combining resistive IMT for 6 weeks with standard training was effective to improve some pulmonary functions in MMA athletes, but did not lead to additional gains in kickboxing athletes.