Chronic Physiological Effects of Swim Training Interventions in Non-Elite Swimmers: A Systematic Review and Meta-Analysis

Effects of Different Types of Physical Activity on Respiratory Health Parameters in Elderly Males: A Cross-Sectional Study

Background Population aging is a global phenomenon associated with declines in muscle mass, physical activity levels, and respiratory health among elderly individuals. Despite evidence suggesting the benefits of physical activity on respiratory function, there is limited research examining its effects on lung function in the Indian elderly population. Materials and methods This cross-sectional study aimed to investigate the impact of different intensities of physical activity on respiratory health parameters among apparently healthy elderly males aged 60-80 years. Participants were categorized into walking, swimming, and sedentary groups based on their level of physical activity. Anthropometric measurements, cardiovascular parameters, respiratory endurance tests, and spirometry were conducted to assess lung function. Statistical analysis included nonparametric tests to compare the groups. Results Age, height, weight, BMI, waist circumference, and hip circumference were similar across groups, but the waist-to-hip ratio was higher in the sedentary group. Systolic and diastolic blood pressure did not differ significantly, while the pulse rate was lower in the swimming group. The sedentary group exhibited lower respiratory endurance, with a significantly reduced 40 mmHg endurance test and maximum expiratory pressure compared to the walking and swimming groups. Spirometry results showed significant improvements in various parameters, including forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), peak expiratory flow rate (PEFR), forced expiratory flow 25% (FEF-25), and maximum voluntary ventilation (MVV) in the walking and swimming groups compared to the sedentary group. Conclusion Regular physical activity, particularly walking and swimming, appears to positively influence respiratory health parameters among elderly males. Engaging in these activities may enhance respiratory muscle strength and lung function, potentially mitigating age-related declines in pulmonary function and promoting overall well-being.

Health Benefits of Different Sports: a Systematic Review and Meta-Analysis of Longitudinal and Intervention Studies Including 2.6 Million Adult Participants

BACKGROUND

Several reviews have examined the health benefits of participation in specific sports, such as baseball, cricket, cross-country skiing, cycling, downhill skiing, football, golf, judo, rugby, running and swimming. However, new primary studies on the topic have recently been published, and the respective meta-analytic evidence needs to be updated.

OBJECTIVES

To systematically review, summarise and appraise evidence on physical health benefits of participation in different recreational sports.

METHODS

Searches for journal articles were conducted in PubMed/MEDLINE, Scopus, SpoLit, SPORTDiscus, Sports Medicine & Education Index and Web of Science. We included longitudinal and intervention studies investigating physical health outcomes associated with participation in a given sport among generally healthy adults without disability.

RESULTS

A total of 136 papers from 76 studies conducted among 2.6 million participants were included in the review. Our meta-analyses of available evidence found that: (1) cycling reduces the risk of coronary heart disease by 16% (pooled hazard ratio [HR] = 0.84; 95% confidence interval [CI]: 0.80, 0.89), all-cause mortality by 21% (HR = 0.79; 95% CI: 0.73, 0.84), cancer mortality by 10% (HR = 0.90; 95% CI: 0.85, 0.96) and cardiovascular mortality by 20% (HR = 0.80; 95% CI: 0.74, 0.86); (2) football has favourable effects on body composition, blood lipids, fasting blood glucose, blood pressure, cardiovascular function at rest, cardiorespiratory fitness and bone strength (p < 0.050); (3) handball has favourable effects on body composition and cardiorespiratory fitness (p < 0.050); (4) running reduces the risk of all-cause mortality by 23% (HR = 0.77; 95% CI: 0.70, 0.85), cancer mortality by 20% (HR = 0.80; 95% CI: 0.72, 0.89) and cardiovascular mortality by 27% (HR = 0.73; 95% CI: 0.57, 0.94) and improves body composition, cardiovascular function at rest and cardiorespiratory fitness (p < 0.010); and (5) swimming reduces the risk of all-cause mortality by 24% (HR = 0.76; 95% CI: 0.63, 0.92) and improves body composition and blood lipids (p < 0.010).

CONCLUSIONS

A range of physical health benefits are associated with participation in recreational cycling, football, handball, running and swimming. More studies are needed to enable meta-analyses of health benefits of participation in other sports. PROSPERO registration number CRD42021234839.

Shoulder pain and injury risk factors in competitive swimmers: A systematic review

AIM

To synthesize and assess the literature for shoulder pain and injury risk factors in competitive swimmers.

DESIGN

Systematic review with best-evidence synthesis.

DATA SOURCES

CINHAL, SportDiscus, Scorpus, PubMed, and Embase databases from 1966 to April 30 2022.

SEARCH AND INCLUSION

Cohort, cross-sectional, and case-control studies investigating shoulder pain or injury risk factors in competitive swimmers were included. Quality of eligible studies were assessed using a modified Newcastle-Ottawa scale. Risk factors were divided into four categories: modifiable-intrinsic, modifiable-extrinsic, non-modifiable, and other/secondary.

RESULTS

Of 1356 studies identified, 24 full texts were evaluated for methodological quality, 22 met the criteria and were included in best evidence synthesis. There was no strong evidence supporting or refuting the association between 80 assessed variables and shoulder injury or pain. The swimmers' competitive level (nondirectional), and shoulder muscle recruitment profiles (e.g., increased activity of serratus anterior) exhibited moderate evidence supporting an association. Conversely, internal and external range of motion, middle finger back scratch test, training frequency, specialty stroke, height/weight, sex, and age all had moderate evidence opposing an association. Limited evidence was found for 58 variables, and conflicting for 8. The highest quality study (n = 201) suggested high acute-to-chronic workload ratio and reduced posterior shoulder strength endurance are associated with injury.

CONCLUSIONS

Due to the paucity of high-quality studies, future prospective studies are needed to reevaluate known risk factor associations over exploring additional potential risk factors. Swimming practitioners should be aware of the nondirectional association of a swimmer's competitive level and pain, as squad changes could impact injury incidence. Moreover, swimmers experiencing shoulder pain may show increased activity in shoulder stabilizers during specific movements. Importantly, shoulder strength-endurance may be the most clinically relevant modifiable intrinsic risk factor.

Aquatic Exercise Impact on Pain Intensity, Disability and Quality of Life in Adults with Low Back Pain: A Systematic Review and Meta-analysis

BACKGROUND

Low back pain is a common, multifaceted disorder that directly affects diverse aspects of people's lives in terms of health, personal and social lives. A variety of pathological disorders, including low back pain, may benefit from hydrotherapy.

OBJECTIVE

This study aimed to systematically analyze the efficacy of aquatic exercise on pain intensity, disability, and quality of life among adults with low back pain.

DATA SOURCES

A systematic search was conducted in PubMed, Web of Science, Medline, and Scopus up to February 2023 for randomized controlled trials (RCTs) that which examined the impact of aquatic exercise. The most relevant articles were selected based on research criteria. The PEDro scale was applied to assess the quality of the included studies. Review Manager 5.3 was used for conducting all analyses.

STUDY SELECTION

Out of 856 articles, 14 RCTs (n = 484 participants; 257 in the experimental groups and 227 in the control groups) met our inclusion criteria.

RESULTS

Pooled results illustrated that aquatic exercises significantly reduced pain (mean differences (MD): -3.82; p < 0.00,001), improved disability (standardized mean differences (SMD): 1.65; p < 0.00,001), and improved quality of life in both the physical component score (mean difference (MD), 10.13; p < 0.00,001) and the mental component score (MD, 6.45; p < 0.0001) when compared with a control group.

CONCLUSION

The current review showed that aquatic exercise regimens were effective among adults with low back pain. High-quality clinical investigations are still needed to support the use of therapeutic aquatic exercise in a clinical setting.

The combined analysis of urine and blood metabolomics profiles provides an accurate prediction of the training and competitive status of Chinese professional swimmers

Objective: The purpose of this study was to employ metabolomics for the analysis of urine metabolites in swimmers, with the aim of establishing models for assessing their athletic status and competitive potential. Furthermore, the study sought to compare the identification efficacy of multi-component (urine and blood) model versus single-component (urine or blood) models, in order to determine the optimal approach for evaluating training and competitive status. Methods: A total of 187 Chinese professional swimmers, comprising 103 elite and 84 sub-elite level athletes, were selected as subjects for this study. Urine samples were obtained from each participant and subjected to nuclear magnetic resonance (NMR) metabolomics analysis. Significant urine metabolites were screened through multivariable logistic regression analysis, and an identification model was established. Based on the previously established model of blood metabolites, this study compared the discriminative and predictive performance of three models: either urine or blood metabolites model and urine + blood metabolites model. Results: Among 39 urine metabolites, 10 were found to be significantly associated with the athletic status of swimmers (p < 0.05). Of these, levels of 2-KC, cis-aconitate, formate, and LAC were higher in elite swimmers compared to sub-elite athletes, while levels of 3-HIV, creatinine, 3-HIB, hippurate, pseudouridine, and trigonelline were lower in elite swimmers. Notably, 2-KC and 3-HIB exhibited the most substantial differences. An identification model was developed to estimate physical performance and athletic level of swimmers while adjusting for different covariates and including 2-KC and 3-HIB. The urine metabolites model showed an area under the curve (AUC) of 0.852 (95% CI: 0.793-0.912) for discrimination. Among the three identification models tested, the combination of urine and blood metabolites showed the highest performance than either urine or blood metabolites, with an AUC of 0.925 (95% CI: 0.888-0.963). Conclusion: The two urine metabolites, 2-KC and 3-HIV, can serve as significant urine metabolic markers to establish a discrimination model for identifying the athletic status and competitive potential of Chinese elite swimmers. Combining two screened urine metabolites with four metabolites reported exhibiting significant differences in blood resulted in improved predictive performance compared to using urine metabolites alone. These findings indicate that combining blood and urine metabolites has a greater potential for identifying and predicting the athletic status and competitive potential of Chinese professional swimmers.

Physical activity and quality of life in children with well-controlled asthma

Background: Asthma is the most common disease in childhood. Appropriate management and programs encouraging exercise enable children to enjoy a good quality of life (QoL).Objective: To assess the association between lung function, physical activity (PA), and QoL in children with well-controlled asthma.Methods: Fifty-four children aged 7 to 14 years attending a Pediatric Asthma Clinic were included. All children underwent spirometry and completed three self-administered validated questionnaires: The Godin Leisure-Time Exercise Questionnaire (GLTEQ), the ACT (Asthma Control Test), and the DISABKIDS for QoL.Results: Mean age of the study population was 11.43(±2.1), BMI, kg/m² (20.8 ± 3.9), FVCpp (97.1% ±12.4), and FEV1pp (99.7% ±12.43), ACT (23.4 ± 3). The GLTEQ revealed that only 3% of the studied population presented satisfactory activity, while 86% were sedentary. Both FEV1pp, and PA were significantly correlated to the children's QoL ((r²: 0.55, p:0.0001), and (r²:0.45, p:0.003), respectively).Conclusions: Despite reasonable asthma control, the children exhibited low physical activity levels, which negatively correlated to their QoL. Families of asthmatic children should be educated to highlight the benefits of exercise and increase the PA of their children.

Epidemiology of children's swimming competence and water safety

Introduction

The main purpose of this study was to investigate children's swimming competence in primary schools of districts in Vojvodina, Serbia.

Methods

Included subjects were primary school students from first to eighth grade (N = 2,778; male = 1,454, female = 1,324; age = 10.73 ± 2.1 years). We used Swimming Competence Questionnaire to acquire and analyze their swimming experience, non-fatal aquatic events, and demographics. For the statistical analysis, logistic regression and hierarchical multiple regression were used to evaluate if the factors and SC and NFAE were associated. The analyses were carried out by using SPSS® software version 24.0 (SPSS, Inc., Chicago, Illinois, USA).

Results

Families with more income and education generally have children with more swimming competence, experience, knowledge, and skills related to water safety. First step in analysis revealed that gender (β = 0.05, p < 0.01), education level (β = 0.06, p < 0.01) age (β = 0.171, p < 0.01), and family income (β = 0.04, p < 0.01) were significant swimming competence (SC) predictors (R2 = 0.04). Age (OR = 1.15, p < 0.01) was the only significant predictor in Step 1 predicting non-fatal aquatic events (NFAE). In Step 2, variables associated with SC were swimming location (ΔR2 = 0.06, p < 0.01), swimming experience (ΔR2 = 0.16, p < 0.01), swimming accessibility (ΔR2 = 0.05, p < 0.01), and learning experience (ΔR2 = 0.03, p < 0.01) (total R2 = 0.26 to 0.47, p < 0.01). Only a minority of participants reported that they could not swim further than 5 meters using general stroke (37.15%).

Conclusion

National education trainers programs must be prioritized with the primary strategy of transferring knowledge to swimming and water safety. Families with lower income must be included without exceptions. This is perhaps a key factor in preventing NFAE, increasing SC, and increasing water safety.

Effects of aquatic high-intensity interval training and moderate-intensity continuous training on central hemodynamic parameters, endothelial function and aerobic fitness in inactive adults

Objective

The effects of land-based high-intensity interval training (HIIT) on the cardiovascular system have already been demonstrated. However, the water environment is different from that on land. Therefore, we investigated the effects of 6-week aquatic HIIT and moderate-intensity continuous training (MICT) on central hemodynamic parameters, endothelial function, and aerobic fitness in inactive adults.

Methods

Thirty-one inactive adults were randomly assigned to HIIT or MICT group. HIIT group performed twelve 30-s swimming exercise bouts with the intensity of 95% HR_max and 15-18/20 RPE with a 60-s rest period between each bout. MICT group performed a 30-min uninterrupted swimming exercise with the intensity of 70%-75% HR_max and 12-14/20 RPE. Training frequency for both groups was three times a week. The pulse wave analysis and flow-mediated dilation (FMD) were measured by non-invasive equipments.

Results

The aerobic fitness significantly increased after HIIT, but no change was seen after MICT. Augmentation pressure (AP) and augmentation index normalized at 75 bpm (AIx@HR75) significantly decreased after HIIT but not MICT, whereas MICT rather than HIIT improved subendocardial viability ratio (SEVR), central and peripheral blood pressure, and resting HR. Only HIIT significantly increased brachial endothelial function.

Conclusion

A six-week aquatic HIIT and MICT had no differences in hemodynamic parameters, endothelial function, and aerobic fitness, however 6 weeks of aquatic HIIT reduced arterial stiffness, increased endothelial function and aerobic fitness, while 6 weeks of aquatic MICT reduced arterial blood pressure and resting HR and increased the coronary blood flow reserve.

Determinants of lung function changes in athletic swimmers. A review

AIM

To summarise lung function characteristics of athletic swimmers and discuss mechanisms explaining these changes while putting forward the lack of a clear understanding of the precise physiological factors implicated.

METHODS

Literature search until 07.2021 on Medline and EMBASE using keywords swimming, athletes, respiratory physiology, lung development, lung function tests. Relevant articles in French and English were reviewed.

RESULTS

We found insufficient data to perform a meta-analysis. However, there is evidence that swimmers have better expiratory flows and increased baseline lung volumes than non-athletes or non-swimmers. Although these features can result from changes in lung development following intense training over the years, the contribution of a genetic predisposition and positive selection cannot be totally excluded.

CONCLUSION

Disentangling the participation of constitutional factors and years of hard training to explain the larger lung volumes of athletic swimmers is in favour of an adaptative response of the lungs to early swim training through modification of the pathway of lung development. There seems to be an optimal window of opportunity before the end of growth for these adaptational changes to occur. Precise mechanisms, and contribution of adaptative change on lung physiology, remain to be further studied.

Efficacy of Therapeutic Aquatic Exercise vs Physical Therapy Modalities for Patients With Chronic Low Back Pain: A Randomized Clinical Trial

IMPORTANCE

Therapeutic aquatic exercise is frequently offered to patients with chronic low back pain, but its long-term benefits are unclear.

OBJECTIVE

To assess the long-term effects of therapeutic aquatic exercise on people with chronic low back pain.

DESIGN, SETTING, AND PARTICIPANTS

This 3-month, single-blind randomized clinical trial with a 12-month follow-up period was performed from September 10, 2018, to March 12, 2019, and the trial follow-up was completed March 17, 2020. A total of 113 people with chronic low back pain were included in the experiment.

INTERVENTIONS

Participants were randomized to either the therapeutic aquatic exercise or the physical therapy modalities group. The therapeutic aquatic exercise group received aquatic exercise, whereas the physical therapy modalities group received transcutaneous electrical nerve stimulation and infrared ray thermal therapy. Both interventions were performed for 60 minutes twice a week for 3 months.

MAIN OUTCOMES AND MEASURES

The primary outcome was disability level, which was measured using the Roland-Morris Disability Questionnaire; scores range from 0 to 24, with higher scores indicating more severe disability. Secondary outcomes included pain intensity, quality of life, sleep quality, recommendation of intervention, and minimal clinically important difference. Intention-to-treat and per-protocol analyses were performed.

RESULTS

Of the 113 participants, 59 were women (52.2%) (mean [SD] age, 31.0 [11.5] years). Participants were randomly allocated into the therapeutic aquatic exercise group (n = 56) or the physical therapy modalities group (n = 57), and 98 patients (86.7%) completed the 12-month follow-up. Compared with the physical therapy modalities group, the therapeutic aquatic exercise group showed greater alleviation of disability, with adjusted mean group differences of -1.77 (95% CI, -3.02 to -0.51; P = .006) after the 3-month intervention, -2.42 (95% CI, -4.13 to -0.70; P = .006) at the 6-month follow-up, and -3.61 (95% CI, -5.63 to -1.58; P = .001) at the 12-month follow-up (P < .001 for overall group × time interaction). At the 12-month follow-up point, improvements were significantly greater in the therapeutic aquatic exercise group vs the physical therapy modalities group in the number of participants who met the minimal clinically important difference in pain (at least a 2-point improvement on the numeric rating scale) (most severe pain, 30 [53.57%] vs 12 [21.05%]; average pain, 14 [25%] vs 11 [19.30%]; and current pain, 22 [39.29%] vs 10 [17.54%]) and disability (at least a 5-point improvement on the Roland-Morris Disability Questionnaire) (26 [46.43%] vs 4 [7.02%]). One of the 56 participants (1.8%) in the therapeutic aquatic exercise group vs 2 of the 57 participants (3.5%) in the physical therapy modalities group experienced low back pain and other pains related to the intervention.

CONCLUSIONS AND RELEVANCE

The therapeutic aquatic exercise program led to greater alleviation in patients with chronic low back pain than physical therapy modalities and had a long-term effect up to 12 months. This finding may prompt clinicians to recommend therapeutic aquatic exercise to patients with chronic low back pain as part of treatment to improve their health through active exercise rather than relying on passive relaxation.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR1800016396.

Produção cientifica sobre natação em língua portuguesa: uma análise bibliométrica

RESUMO O estudo analisou a produção científica sobre natação em língua portuguesa por meio da bibliometria. A busca ocorreu nas bases Scientific Electronic Library Online, Biblioteca Virtual em Saúde e Scopus, desde seu início até setembro de 2022. Duzentos e trinta e dois artigos completos foram incluídos. A produção aumentou consideravelmente nas duas últimas décadas, sendo predominantemente concentrada nas regiões Sudeste e Sul, em periódicos A2 a B2 do Qualis-CAPES 2013-2016. Biomecânica e fisiologia foram as áreas mais estudadas. A maior parte dos estudos é de natureza quantitativa, observacional e transversal, direcionados à população adolescente e atleta. A quantidade e variedade de estudos demonstra o interesse da comunidade científica em investigar aspectos relacionados à natação.

An Updated Review of the Epidemiology of Swimming Injuries

OBJECTIVE

To carry out a systematic review to update the scientific evidence on the incidence and prevalence of injuries in the swimming discipline, as well as the location, type, and mechanism of the injuries, and to assess whether studies are meeting methodological recommendations for data collection and injury surveillance. TYPE: Analytical-Systematic review.

LITERATURE SURVEY

The databases of PubMed and Sportdiscus were used to search for studies that describe the epidemiology of injuries in adult swimmers between 2010 and March 2020.

METHODOLOGY

Of the 864 articles identified, 14 studies were finally included in this review. The methodological quality of the studies was analyzed with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) scale and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed.

SYNTHESIS

The results showed a high prevalence of shoulder, knee, and lower back injuries among swimmers due to overuse. These injuries were mainly short-term tendon muscles; there were reported data differences between genders.

CONCLUSIONS

Despite the publication of an injury surveillance single and multisport events document and a consensus on data collection and injury surveillance in swimming, there are huge methodological limitations that do not allow firm conclusions. As such, more epidemiological studies following guidelines for data collection and injury surveillance are needed to establish differences by gender, age group, and swimming stroke.

Descriptive epidemiology and correlates of children's swimming competence

This study examined the swimming competence of primary school children, and how it was related to swimming activity, non-fatal aquatic events, and demographic factors. Primary school students (N = 4959; female = 2705, male = 2241; age range = 5 to 14 years) across 28 schools in the 15 districts of Hong Kong completed the Swimming Competence Questionnaire, and questions about their swimming experience, non-fatal aquatic events, and demographic variables. Descriptive statistics showed that over 60% of children could swim more than 5m, but less than 50% could swim over 25m. Over 50% of children were able to perform some basic swimming skills (e.g., holding breath underwater, floating, poolside/kickboard kicking, and treading water). Swimming competence was positively predicted by the demographic factors (i.e., age, sex, family income, and parents' highest education level), swimming experience, learning experience, and swimming location. Treading water was the only factor of swimming competence that established asignificant negative association with non-fatal aquatic events. Current results can be used to target key groups to improve children's swimming competence and reduce non-fatal aquatic events; children from lower socio-economic backgrounds and with less swimming experience should be encouraged to participate in more formal learn to swim lessons.

The effect of 8 weeks of freestyle swim training on the functional fitness of adults with Down syndrome

BACKGROUND

Studies conducted on adults with Down syndrome have demonstrated the improvement of functional fitness (aerobic capacity, muscular strength, balance, flexibility, functional ability, body mass or body mass index) with varying exercise modalities but often with one or two components in isolation. Such modalities included walking, running, cycling, rowing or resistance training. Freestyle swim training has shown significant improvements of all parameters associated with functional fitness in the general population. Swimming is an aerobic activity where many of the large muscle groups are involved and may provide more functional fitness benefits. As a consequence, the purpose of our study was to investigate the effect of freestyle swim training on the functional fitness of adults with Down syndrome.

METHODS

Twenty-six adults with Down syndrome (33 ± 6 years; 34 ± 9 kg/m² ) were randomly allocated to an exercise (n = 13; 81.3 kg) or control group (n = 13; 81.5 kg). The exercise group performed 8 weeks of freestyle swim training, three times a week, 30 min per session (increased to 40 min after 4 weeks). To evaluate differences between groups, a one-way analysis of variance was used, controlling for differences at baseline.

RESULTS

After 8 weeks of training, the results showed significant differences between the exercise and control group for body mass, body mass index, aerobic capacity, dynamic balance, muscular strength, 12-m swim time and functional ability (P < 0.05). Effect sizes ranged from small to large.

CONCLUSIONS

Various components of functional fitness improved significantly after an intervention period of freestyle swim training. The collective improvement of many functional fitness parameters shown by this study may hold benefits for these often-neglected and in many cases functionally impaired individuals.

Anthropometric and Motor Competence Classifiers of Swimming Ability in Preschool Children-A Pilot Study

Swimming is a form of physical activity and a life-saving skill. However, only a few studies have identified swimming ability classifiers in preschool children. This pilot cross-sectional study aimed to find anthropometric (AM) and motor competence (MC) predictors of swimming ability in preschool children, by building classifiers of swimming ability group (SAG) membership. We recruited 92 children (girls n = 45) aged 5-6 years and took the AM and MC measurements in accordance with the reference manual and using the KTK battery test (motor quotient, MQ), respectively. A linear discriminant analysis tested a classification model of preschoolers' swimming ability (SAG: POOR, GOOD, EXCELLENT) based on gender, age, AM, and MC variables and extracted one significant canonical discriminant function (model fit: 61.2%) that can differentiate (group centroids) POOR (-1.507), GOOD (0.032), and EXCELLENT (1.524). The MQ total was identified as a significant classifier, which absolutely contributed to the discriminant function that classifies children's swimming ability as POOR (standardized canonical coefficient: 1.186), GOOD (1.363), or EXCELLENT (1.535) with an accuracy of 64.1%. Children with higher MQ total ought to be classified into higher SAG; thus, the classification model of SAG based on the MQ total is presented.

Validation of the swimming competence questionnaire for children

Two studies were employed to test the reliability and validity of the Swimming Competence Questionnaire (SCQ) among primary school children. Study 1 was a cross-sectional survey in 4959 primary school children. Study 2 was a pre-post-test quasi-experiment among 1609 primary school children who underwent a 20-lesson learn-to-swim programme. In Study 1, exploratory structural equation modelling revealed excellent goodness-of-fit and scale reliability for a two-factor model comprising distance and skill factors, which supported the construct and convergent validity. SCQ scores were significantly and positively correlated with swimming outcomes (i.e., self-efficacy, intention, swimming frequency), which supported SCQ's concurrent and criterion validity. Average variance extracted for the SCQ factors exceeded cut-off criteria supporting discriminant validity. In Study 2, pre-test SCQ scores correlated significantly and positively with the SCQ scores, self-efficacy, intention, and swimming frequency at post-test, which supported SCQ's test-retest reliability and predictive validity. Positive intraclass correlation between SCQ scores and coach ratings at post-test provided evidence for SCQ's inter-rater reliability. SCQ scores significantly improved at post-test, which supported SCQ's ecological validity. In conclusion, findings indicate that the SCQ is a valid and reliable measure to assess primary school children's swimming competence, in terms of swimming distance and basic water survival skills.

An enjoyable school-based swimming training programme improves students' aquaticity

AIM

The main objectives of this research were to a) examine the test-retest reliability of aquaticity test (study 1), b) investigate the efficacy of 'swimming lesson', during the physical education course, in the aquaticity (study 2) and c) examine enjoyment from the 'swimming lesson' (study 3) in primary school students of the 3rd grade.

METHODS

In the first study, 23 students performed 2 assessment sessions for the evaluation of aquaticity, separated by 1 week. In the second study, 30 students followed a short-term swimming training programme (9 sessions). Before and after the programme, students' aquaticity was assessed. In the third study, enjoyment was examined in 273 students who followed the short-term swimming programme.

RESULTS

The test-retest reliability for the assessment of students' aquaticity was high (ICC = 0.87-0.99). Paired t tests, also, revealed significant improvement (28-62.7%) in the aquaticity of the children following the swimming programme. A great percentage of students reported high levels of enjoyment (92.2%).

CONCLUSION

A short-term swimming programme, incorporated into the physical education course, is an enjoyable exercise modality that may be used for the improvement of children's aquaticity. We, also, found that the testing protocol may be reliably used for the evaluation of aquaticity in the paediatric population.

Exercise and lifestyle changes in pediatric asthma

PURPOSE OF REVIEW

The purpose of this review is to discuss the most recent studies on lifestyle interventions in pediatric asthma. We include studies on physical activity and exercise, sedentary time, nutrition, behavioral therapy and the role of schools.

RECENT FINDINGS

Several small studies in children with asthma suggest that exercise interventions can improve aerobic fitness, asthma symptoms or control and quality of life. Existing evidence supports recommending higher intake of fruits and vegetables for asthma risk and control. In contrast, the 'Western diet' - high in refined grains, highly processed foods, red meats and fried foods with low intake of fruits and vegetables - has a proinflammatory effect and may alter microbiota composition leading to worse asthma outcomes. Finally, there are opportunities to utilize schools to promote physical activity, though standardization of asthma management in the schools is needed.

SUMMARY

Assessing physical activity/fitness levels, sedentary time and nutritional status is important in the management of children with asthma, as they are modifiable factors. Larger rigorous studies evaluating lifestyle interventions are needed to better inform current asthma guidelines as well as to understand the underlying mechanism(s) related to physical activity and diet in asthma.

Swimming-related effects on cerebrovascular and cognitive function

Both acute and regular exercise influence vascular and cognitive function. Upright aquatic exercise increases mean middle cerebral artery blood velocity (MCAvmean ) and has been suggested as favorable for cerebrovascular adaptations. However, MCAvmean has not been reported during swimming. Thus, we examined the cerebrovascular and cognitive effects of swimming. Ten land-based athletes (22 ± 5 years) and eight swimmers (19 ± 1 years) completed three cognitive tasks and four conditions that were used to independently and collectively delineate the swimming-related factors (i.e., posture, immersion, CO2 retention [end-tidal CO2 ; PETCO2 ], and motor involvement). Measurements of MCAvmean and PETCO2 were taken throughout each condition. Prone posture increased MCAvmean by 11% (P < 0.01 vs. upright land). Water immersion independently increased MCAvmean when upright (12%; P < 0.01) but not prone (P = 0.76). The consequent rise in PETCO2 during head-out, breast-stroke swimming (50% heart rate range) independently increased MCAvmean by 14% (P < 0.01), while the motor involvement of swimming per se did not significantly change MCAvmean (P = 0.32). While accounting for sex, swimmers had ~17% lower MCAvmean during all rest conditions (P ≤ 0.05). However, in a subset of participants, both groups had similar internal carotid artery diameters (P = 0.99) and velocities (P = 0.97). Water immersion per se did not alter cognition (P ≥ 0.15), but 20 min of moderate-intensity swimming improved visuomotor performance by 4% (P = 0.03), regardless of athlete group (P = 0.12). In conclusion, breast-stroke swimming increased MCAvmean mostly due to postural and PETCO2 effects, with minimal contributions from water immersion or motor activity. Lastly, swimming improved cognitive functioning acutely, regardless of athlete group. Future research should explore the chronic effects of swimming on cerebrovascular function and cognition, particularly in aging.

Exhaled nitric oxide as a marker of chlorine exposure in young asthmatic swimmers

BACKGROUND

Swimming is recommended for people with asthma. However, the inevitable exposure to chlorine and its disinfectant byproducts in indoor swimming pools could be responsible for bronchial inflammation and asthma development. Fractional exhaled nitric oxide (FeNO) is a noninvasive marker of airway inflammation that predicts asthma exacerbations.

OBJECTIVES

To evaluate pretraining and posttraining FeNO levels in young swimmers with asthma attending an indoor chlorinated pool compared with a set of healthy swimmers and to examine the potential risk of exposure to chlorine as a factor associated with bronchial inflammation.

METHODS

A total of 146 children (8-18 years old) constantly attending an indoor chlorinated swimming pool were enrolled. Spirometry and FeNO measurements were performed 30 minutes after their arrival at the pool and immediately after exercise. Pre-exercise and postexercise spirometric and FeNO levels were assessed in a random subgroup of 14 swimmers (10 with asthma and 4 without) who performed cardiopulmonary exercise testing.

RESULTS

Asthma was detected in 23 swimmers. In swimmers with asthma, preswimming FeNO values were significantly elevated compared with swimmers without asthma and their FeNO values measured before cardiopulmonary exercise testing. Postexercise FeNO values were significantly decreased by approximately one-third in healthy children and children with asthma in all sporting backgrounds. However, postswimming FeNO values remained significantly higher in swimmers with asthma compared with those without asthma. Forced expiratory volume in 1 second (FEV₁), forced vital capacity (FVC), and FEV₁/FVC ratio values showed no significant difference before and after 2 types of activity.

CONCLUSION

Elevated FeNO levels before and after swimming were recorded in swimmers with asthma not observed in a different exercise field. The presence of chlorine in the indoor swimming pool seems to explain this finding.