Ferman Konukman, Qatar University, Qatar
This is an open-access article distributed under the terms of the
This study aimed to investigate the effects of combining inspiratory muscle resistance with strength training on lung function and aerobic capacity in artistic swimmers.
This research constitutes a placebo-controlled randomized trial, involving a five-week walking program conducted twice a week. Fourteen female artistic swimmers were randomly assigned to either the experimental group (TG group,
Following the 5-week intervention, within-group comparisons revealed that the inspiratory muscle strength index, vital capacity, and forced vital capacity significantly increased in both the CG and TG groups (
The findings suggest that a 5-week program combining inspiratory muscle resistance with strength training can effectively enhance the aerobic exercise capacity of artistic swimmers. Moreover, high-intensity inspiratory muscle resistance combined with strength training can improve the muscle's ability to utilize oxygen during exercise.
Beijing Research Institute of Sports Science (TKSLL202201); China Clinical Trial Registry, ChiCTR2300072833, 26/06/2023.
Artistic swimming perform strenuous underwater exercise during prolonged breath holds. Approximately 50%–65% of the movements in a artistic swimmer's routine require prolonged breath-holding in the water, coupled with the completion of high-intensity physical leg combinations and treading actions. This necessitates athletes to maintain a high vital capacity and low breathing rate simultaneously, placing heightened demands on inspiratory muscle strength. Studies on the control of ventilation in elite artistic swimmers show that elite artistic swimmers have increased lung volumes, blunted hypoxic ventilatory responses, and a marked apneic bradycardia that may provide physiological characteristics that offer a competitive advantage for championship performance (
Numerous studies have indicated that inspiratory muscle training can enhance ventilation efficiency by augmenting inspiratory explosiveness and tidal volume, aligning with the respiratory requirements of artistic swimming events. In the García I study (
The primary objective of this study is to examine the effect of a 5-week combined regimen of inspiratory muscle resistance and strength training on enhancing aerobic capacity in artistic swimmers. It aims to provide methodological support for improving the overall competitive ability of artistic swimmers.
The Beijing artistic swimming team consists of 14 female athletes (mean age 19.9 ± 3.1years) renowned for their collective event championships in national artistic swimming competitions. Prior to the experimental phase, all participants underwent a thorough screening process, ensuring they were non-smokers with no history of disease, metabolic or endocrine disorders, and possessed normal pulmonary function. Detailed information about the experiment's objectives, training procedures, potential physical discomfort, and the voluntary nature of their participation was provided to the subjects. Furthermore, participants were required to provide informed consent and pledge full cooperation throughout the experiment. Using a random number table, the subjects were divided into a control group (CG) and an experimental group (TG), each comprising 7 individuals. This allocation resulted in comparable basic information between the two groups (
Basic information of subjects recruited.
| Group | Height (cm) | Weight (kg) | Age 9 years) | training experience (years) |
|---|---|---|---|---|
| CON ( |
166.5 ± 3.5 | 51.7 ± 3.5 | 20.6 ± 3.1 | 11.1 ± 3.0 |
| EXP ( |
167.3 ± 3.2 | 50.9 ± 4.5 | 19.0 ± 2.8 | 10.9 ± 2.7 |
This research constitutes a placebo-controlled randomized trial, involving a five-week walking program conducted twice a week. The TG group underwent combined inspiratory muscle strength training at an intensity of 50% maximal inspiratory pressure (MIP), while the CG group engaged in the same training at 15% MIP intensity. Both groups followed artistic breathing patterns and coordinated physical activity during training, focusing on utilizing abdominal breathing and ensuring forceful inhalation during exercises in synchronization with strength training movements. Each set comprised 8 movements with 6–8 repetitions per movement, totaling 3 sets with 60-second intervals between each set. Furthermore, participants exhaled during exertion and inhaled during the reset phase of each movement to maintain consistent breathing patterns throughout the training sessions.The subjects' maximum oxygen uptake, resting lung function, inspiratory muscle strength, and swimming performance were evaluated before and after the training phase, See
Specialized strength training regimen.
| Item | load | Groups (group) | Times | Intermittent period |
|---|---|---|---|---|
| Squats | 40 kg | 3 | 6 | 60 s |
| pull-up | 10 kg | 3 | 6 | 60 s |
| single-leg deadlift Bosu ball | 6 kg | 3 | 8 repetitions per leg | 60 s |
| Lift one arm while in a kneeling position | 7.5 kg | 3 | 8 repetitions per leg | 60 s |
| Replicates an inverted water push-up | Elastic bands | 3 | 15 | 60 s |
| Kneeling rotation | 6 kg | 3 | 8 repetitions per leg | 60 s |
| Alternating leg lifts on the BOSU ball | 1 kg | 3 | 15 repetitions per leg | 60 s |
| Prone back stretches | 6 kg | 3 | 15 | 60 s |
IM-related parameters, including the S-Index、peak inspiratory flow (PIF) and the maximum inspiratory pressure (MIP), were assessed using the PowerBreathe KH2 device. Initially, the supporting software Breathe Link was installed on a computer, and the pertinent information for all 14 subjects was entered into the software. Subsequently, the PowerBreathe KH2 was linked to the computer, and the software interface was configured for the testing process. The system was configured to initiate a test mode, which entailed 30 consecutive forceful inhalations without any time constraints. The software was designed to detect the shaded segment within the inhalation curve, displaying the maximum value from the previous test, providing a reliable means to quantify the subjects' basic data and assess the training effects. Throughout the test, participants were instructed to perform forceful inhalations while refraining from engaging in compensatory maneuvers.
Pulmonary function assessments were carried out using the CHEST H-101 resting pulmonary function analyzer, a Japanese-made device renowned for its capability to measure and analyze exhaled and inhaled gas flow and volume. This analysis provides crucial lung ventilation indices such as slow vital capacity (SVC), minute voluntary ventilation (MVV), and forced vital capacity (FVC), derived from the time-volume curve and flow-volume curve. The device is initiated to commence testing, and subsequently, sequential testing for SVC, FVC, and MVV is performed. Both SVC and FVC tests are conducted twice to ensure accurate results, while the MVV test is performed once. This standardized approach ensures consistency for comparative analysis.
The study assessed the subjects' maximum oxygen uptake (VO2max) and ventilation threshold (VT) using a treadmill protocol. Prior to the test, participants were equipped with heart rate monitors, and safety belts, and underwent a 5 min warm-up on the treadmill. Upon donning the gas metabolism analyzer, the incremental exercise stress test is initiated.
The formal test began at a speed of 7 km/h, gradually increasing to 16 km/h, and then maintaining this speed until exhaustion. During the 7 km/h to 16 km/h phase, the speed increased by 1 km/h per minute, with the treadmill set at a 0% slope. Subsequently, the gradient increased by 1% per minute while maintaining the 16 km/h speed.
Test discontinuation criteria included reaching a respiratory quotient (RQ) at or near 1.15, achieving maximum heart rate (220-age) or a heart rate above 180 bpm, observing an oxygen uptake plateau, or exhibiting an inability to continue exercising. Real-time monitoring of metabolic and ventilation parameters was conducted using a gas metabolizer (smax58ce-sp, China), with data collected by a computer data analysis system. The VT was determined using the V-slope method, and the velocity at ventilatory thresholds (vVT) and the percentage of the ventilation threshold to the maximum oxygen uptake (VT/VO2max) were calculated. Additionally, the study evaluated the maximal oxygen uptake (VO2max), ventilatory threshold onset, and duration of escalating load exercise.
In consideration of the energy supply characteristics and specific program demands in artistic swimming, we have selected the following test parameters to further validate its training effectiveness.
25 m torpedo: special swimming capacity; 50 m diving: breath-holding capacity.
Following the verification of the experimental data, statistical analysis was conducted using SPSS 25.0 software. The normal distribution of continuous data was assessed with the Shapiro-Wilk test. Within-group differences were evaluated using the paired samples
No significant differences were observed between the CON and EXP groups with regard to age, height, and weight. Subjects in both groups exhibited no metabolic disorders, endocrine disorders, or abnormal pulmonary function. Additionally, before training, there were no significant disparities in respiratory muscle function, resting pulmonary function,maximal oxygen uptake and ventilation threshold,or specific exercise capacity test between the two groups.
The impact of combining inspiratory muscle resistance with strength training on parameters related to inspiratory muscle strength.
| Indexs | Groups | Pretest | Posttest |
|---|---|---|---|
| S-index (cmH2O) | CG ( |
96.9 ± 4.5 | 115.4 ± 7.9 |
| TG ( |
100.9 ± 6.9 | 126.2 ± 7.6 |
|
| PIF (L/S) | CG ( |
5.02 ± 0.50 | 6.36 ± 0.66 |
| TG ( |
4.94 ± 0.36 | 6.72 ± 0.46 |
Longitudinal comparison in the same group (compared with pretest results).
With significant differences (
With very significant differences (
With significant differences (
As depicted in
The impact of combining inspiratory muscle resistance with strength training on parameters related to resting pulmonary function.
| Group | SVC (L) | FVC (L) | MVV (L/min) | |||
|---|---|---|---|---|---|---|
| Pretest | Posttest | Pretest | Posttest | Pretest | Posttest | |
| CG | 4.27 ± 0.26 | 4.56 ± 0.27 |
3.55 ± 0.26 | 3.93 ± 0.16 |
110.03 ± 7.26 | 127.59 ± 7.57 |
| TG | 4.34 ± 0.31 | 4.78 ± 0.40 |
3.71 ± 0.15 | 4.20 ± 0.23 |
109.08 ± 4.54 | 133.11 ± 11.57 |
Longitudinal comparison in the same group (compared with pretest results).
With significant differences (
With very significant differences (
With significant differences (
Based on the data in
The impact of combining inspiratory muscle resistance with strength training on parameters related to aerobic capacity.
| Index | Unit | CG ( |
TG ( |
||
|---|---|---|---|---|---|
| Pretest | Posttest | Pretest | Posttest | ||
| VT | ml/min/kg | 38.0 ± 4.8 | 39.8 ± 7.1 | 39.6 ± 4.7 | 42.7 ± 5.9 |
| VT/VO2max (%) | % | 77.9 ± 6.6 | 79.2 ± 6.6 | 77.3 ± 6.2 | 80.4 ± 5.1 |
| vVT | km/h | 12.0 ± 0.8 | 12.2 ± 0.8 | 12.0 ± 1.0 | 12.6 ± 0.8 |
| VO2max | ml/min/kg | 48.7 ± 4.0 | 50.4 ± 6.3 | 51.2 ± 4.9 | 53.0 ± 5.0 |
| vVO2max | km/h | 15.5 ± 1.5 | 16.4 ± 1.1 | 16.3 ± 1.0 | 16.6 ± 1.1 |
| VEmax | L/min/kg | 1.9 ± 0.2 | 1.9 ± 0.2 | 2.0 ± 0.3 | 2.0 ± 0.2 |
| Vtex | ml/kg | 31.8 ± 3.2 | 35.9 ± 4.9 |
33.0 ± 4.1 | 37.7 ± 4.1 |
Longitudinal comparison in the same group (compared with pretest results).
With significant differences (
With very significant differences (
With significant differences (
As indicated in
The impact of combining inspiratory muscle resistance with strength training on parameters related to specialized tests.
| Index | Group | Pretest | Posttest |
|---|---|---|---|
| 50 m diving (s) | CG ( |
35.2 ± 1.7 | 33.9 ± 2.5 |
| TG ( |
36.1 ± 0.9 | 33.7 ± 0.7 |
|
| 25 m torpedo (s) | CG ( |
23.5 ± 0.6 | 22.9 ± 0.5 |
| TG ( |
23.8 ± 0.7 | 22.0 ± 0.7 |
Longitudinal comparison in the same group (compared with pretest results).
With significant differences (
With very significant differences (
With significant differences (
With the continuous development of the sport, artistic swimming, and the athletes' competitive level, require the choreography of artistic swimming to develop in the direction of faster, more difficult and more intense. The respiratory pattern of artistic swimming includes a rapid forced inspiratory phase and a prolonged breath-holding apnea phase while submerged. This entails a high metabolic demand and recurrent apnea in the aquatic environment leading to bradycardia and a suppressed hypoxic respiratory response (
The available research highlights that inspiratory muscle training is effective in enhancing gas exchange capacity and diminishing inspiratory muscle fatigue. This, in turn, improves lung function and aerobic capacity, ultimately resulting in enhanced exercise performance1–11.According to the studies (
This study aims to explore the impact of a five-week inspiratory muscle resistance combined with strength training on the pulmonary function and exercise capacity of artistic swimmers.After different intensities of inspiratory muscle resistance combined with strength training, the lung function and inspiratory muscle strength of the subjects in both groups were significantly improved, which was reflected in the significant increase in inspiratory muscle strength index, vital capacity and forced vital capacity after the stage training. The peak inspiratory flow rate and minute ventilation in the TG group were significantly improved after training. The comparison between groups showed that the inspiratory muscle strength index and ventilation per minute were significantly improved, suggesting that the combination of high-intensity inspiratory muscle resistance training and strength training had a better effect on improving the strength of inspiratory muscles and the endurance level of respiratory muscles in artistic swimmers. The increase in inspiratory muscle strength results in greater force production during diaphragm and other inspiratory muscle contractions, leading to increased diaphragm displacement during breathing, consequently expanding chest volume and promoting lung expansion (
And our study found that the aerobic exercise capacity of athletes in the TG group was significantly improved after the stage of inspiratory muscle resistance combined with strength training, and the improvement effect was better than that of the CG group, which was reflected in the fact that after the stage training, the tidal volume of the CG group and the TG group was significantly improved, and the corresponding running speed of the TG group when the ventilation threshold and maximum oxygen uptake were significantly increased. In addition, comparisons between groups showed that the TG group had a significant increase in running speed when the VO2 maxima was reached.The TG group had a significantly higher increase in running speed when reaching VO2 maxima than the CG group, and it was believed that the form of inspiratory muscle resistance combined with strength training improved the efficiency of lung ventilation and the functional ability of respiratory muscles. In addition, the reduction of metabolites also reduces the stimulation of metabolic receptors of respiratory muscles and increases the threshold of metabolic reflex activation (
The primary aim of inspiratory muscle training is to establish a foundation for improving performance in aquatic specialized exercises (
The analysis of the test results of 25-meter torpedo and 50-meter diving after stage training found that the special swimming ability of athletes was significantly improved after stage inspiratory muscle resistance and combined strength training, which was reflected in the fact that the 25-meter torpedo and 50-meter diving in the CG group and TG group were significantly improved after stage training. In addition, the comparison between groups showed that the 25-meter torpedo in the TG group was significantly improved, and it was believed that the stage of inspiratory muscle resistance combined with strength training significantly improved the breath-holding ability and special swimming ability of artistic swimmer.
Support for these findings can also be found in the work reported similar results on the positive impact of inspiratory muscle training on the specialized exercise ability of artistic swimmers. Additionally, Volianitis S's study (
In summary, the observed enhancements in athletes' specialized exercise ability as a result of inspiratory muscle resistance training are linked to improved inspiratory muscle function and ventilation efficiency. Furthermore, the improvement in respiratory regulation ability, including breathing control and depth, is considered to be a contributing factor to these outcomes.
This study presents novel insights into the potential of inspiratory muscle training to enhance athletes' specific exercise abilities. However, it is important to note that the findings may be constrained by the small sample size. Despite meeting the requirements calculated by G-Power, the current sample size is small. Therefore, we are contemplating expanding the sample size in future studies to bolster the stability and reliability of the results.
A five-week combined inspiratory muscle resistance and strength training regimen can significantly enhance the aerobic capacity of artistic swimmers, thereby establishing a basis for elevating the competitive standard in artistic swimming. Both high-intensity and low-intensity inspiratory muscle resistance combined with strength training can effectively enhance the inspiratory muscle function and overall cardiopulmonary capacity of athletes. Furthermore, high-intensity inspiratory muscle resistance combined with strength training demonstrates superior efficacy in enhancing the ability of artistic swimmers to optimize oxygen utilization within exercising muscles.
The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding author.
The studies involving humans were approved by China Clinical Trial Registry, ChiCTR2300072833, 26/06/2023. The studies were conducted in accordance with the local legislation and institutional requirements. The participants provided their written informed consent to participate in this study. Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article.
YF: Conceptualization, Data curation, Formal Analysis, Funding acquisition, Investigation, Methodology, Project administration, Resources, Software, Supervision, Validation, Visualization, Writing – original draft, Writing – review & editing. YD: Methodology, Writing – review & editing. ZG: Funding acquisition, Resources, Writing – review & editing. YL: Funding acquisition, Project administration, Resources, Writing – review & editing.
The author(s) declare that no financial support was received for the research, authorship, and/or publication of this article.
The authors are grateful to the participants for their time and investment in the investigation. The authors would like to express their gratitude to head coach Min Li and Yu Deng Ma from the Beijing Team. We express our gratitude to them for their meticulous coordination in implementing the training plan with the subjects during the experiment, as well as for their valuable support and assistance throughout.
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.