A 2-year longitudinal follow-up of performance characteristics in Chinese male elite youth athletes from swimming and racket sports

Effects of Swimming Exercise on Early Adolescents' Physical Conditioning and Physical Health: A Systematic Review

BACKGROUND/OBJECTIVES

Swimming is a popular and cost-effective way to prevent sedentary behavior and improve physical conditioning and health during early adolescence. However, information on its impact and benefits on daily life activities is lacking. This systematic review aims to summarize the chronic effects of swimming on physical conditioning and physical health outcomes in early adolescents.

METHODS

The PRISMA 2020 guidelines were followed and PubMed, Scopus, Web of Science, and International Symposium of Biomechanics and Medicine in Swimming proceedings databases were searched. Eligibility criteria were defined on the PICOS framework (healthy adolescents in early puberty, swimming programmes or training, passive or active control groups, general effects on physical conditioning or health, longitudinal) and risk of bias was assessed using RoBANS 2.

RESULTS

From 2365 records, 20 non-randomized studies met the defined criteria. High heterogeneity in sample size and intervention was observed. While studies related to physical conditioning (n = 5) focused on physiological variables and muscular function, the evidence regarding physical health outcomes (n = 15) explored bone accrual, haemodynamics, body composition, musculoskeletal system, and lung growth. High overall risk of bias (70%) was observed due to strict criteria.

CONCLUSIONS

Swimming exercise seems to improve cardiorespiratory fitness, cardiac output, haemodynamics, heart growth, motor performance, and body composition of early adolescents. Despite clear evidence that exists on these chronic effects, research on bone health, postural deficit, motor skills, and sleep quality is still missing.

Usefulness of frailty assessment using the revised Japanese version of the Cardiovascular Health Study on the prediction of clinical outcomes in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement

Frailty assessment is essential for deciding the treatment strategy for patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR). Recently, the revised Japanese version of the Cardiovascular Health Study (J-CHS) criteria has been proposed for the frailty assessment; however, it is unclear whether the criteria are useful for the risk stratification in these patients. We investigated the impact of frailty assessment using the revised J-CHS criteria on clinical outcomes in patients with AS undergoing TAVR. We examined 205 consecutive severe AS patients who underwent TAVR at two tertiary hospitals from May 2018 to December 2022. Frailty was defined by the revised J-CHS criteria (score ≥ 3) before TAVR. The primary outcome was major adverse cardiac or cerebrovascular events (MACCE). Among the studied patients, the mean age was 84 years and 65% were female. Frailty was present in 51% of patients. During a median follow-up period of 1000 (interquartile range 677-1210) days, MACCE occurred in 22 patients. Frailty was significantly independently associated with higher risks of the MACCE adjusted for confounders related to nutritional status, severity of AS, comorbidities [hazard ratio (HR) 5.09, 95% confidence interval (CI) 1.70-15.23; HR 3.94, 95% CI 1.34-11.55; HR 3.12, 95% CI 1.14-8.53; HR 3.31, 95% CI 1.21-9.02, respectively]. Frailty determined by the revised J-CHS criteria was associated with clinical outcomes, suggesting these criteria would be useful for risk stratification in Japanese patients with AS undergoing TAVR.

Mental Health Among Elite Youth Athletes: A Narrative Overview to Advance Research and Practice

CONTEXT

Participation in sports during youth is typically beneficial for mental health. However, it is unclear whether elite sport contexts contribute to greater risk of psychological distress or disorder. The aims of this paper are to highlight conceptual issues that require resolution in future research and practice, and to examine the key factors that may contribute to the mental health of elite youth athletes (EYAs).

EVIDENCE ACQUISITION

A narrative overview of the literature combined with the clinical and research expertise of the authors.

STUDY DESIGN

Narrative overview.

LEVEL OF EVIDENCE

Level 5.

RESULTS

EYAs experience a range of biopsychosocial developmental changes that interact with mental health in a multitude of ways. In addition, there are various sport-specific factors that contribute to the mental health of EYAs that may become more prominent in elite contexts. These include - but are not limited to - patterns relating to athlete coping and self-relating styles, the nature of peer, parental, and coach relationships, organizational culture and performance pressures, and mental health service provision and accessibility.

CONCLUSION

A range of critical factors across individual, interpersonal, organizational, and societal domains have been shown to contribute to mental health among EYAs. However, this evidence is limited by heterogeneous samples and varied or imprecise terminology regarding what constitutes "youth" and "elite" in sport. Nevertheless, it is clear that EYAs face a range of risks that warrant careful consideration to progress to best practice principles and recommendations for mental health promotion and intervention in elite youth sport.

SORT

Level C.

Multidimensional and Longitudinal Approaches in Talent Identification and Development in Racket Sports: A Systematic Review

BACKGROUND

Better methods to support talent identification and development processes may contribute to more effective and efficient athlete development programs in racket sports. Both researchers and practitioners recommend multidimensional and longitudinal approaches to better understand the nature of talent (development). However, the added value of these 'innovative' approaches has not yet been clarified for racket sports. This systematic review intends to gain further insight into the outcomes of multidimensional and longitudinal approaches for talent identification and development in racket sports and to provide directions for future talent research.

METHODS

Electronic searches were conducted in PubMed, Scopus, SPORTDiscus, and Web of Science (January 2000-August 2022). Search terms covered the areas of racket sports and talent in sports. Studies using multidimensional and/or longitudinal talent approaches were included and analyzed regarding the methodology, included performance characteristics (i.e., anthropometrical, physiological, technical, tactical, psychological), and study findings.

RESULTS

A total of thirty-two studies were included using multidimensional (n = 15), unidimensional longitudinal (n = 3) or multidimensional longitudinal designs (n = 14). Most research covered physiological characteristics (n = 28), while fewer articles investigated anthropometrics (n = 21) and technical characteristics (n = 16). Only limited research investigated psychological (n = 4) and tactical characteristics (n = 1). Almost all studies measured physiological characteristics in combination with other characteristics. There was moderate to strong evidence that physiological and technical characteristics have value for athlete development programs in racket sports. Positive but limited evidence was found for psychological and tactical characteristics. Anthropometrical assessments were generally used as controlling variables for maturation. Study designs varied, and many studies used unidimensional statistical models and analyses within multidimensional study designs and datasets.

CONCLUSIONS

This review provides an overview of talent research using multidimensional and/or longitudinal approaches within racket sports and gives guidance on what characteristics to include in decision-making and monitoring processes. However, it remains difficult to draw conclusions about the added values of these approaches due to their variety in methodology. Future talent research should include more consistent study designs and conduct multidimensional and longitudinal studies using multivariate statistical approaches that benefit from the data's multidimensionality.

The Impacts of Sports Schools on Holistic Athlete Development: A Mixed Methods Systematic Review

BACKGROUND

To understand the multiple and wide-ranging impacts of intensified youth sport, the need for a holistic approach to athlete development has recently been advocated. Sports schools are an increasingly popular operationalisation of intensified youth sport, aiming to offer an optimal environment for holistic development by combining sport and education. Yet, no study has systematically explored the impacts associated with sports schools.

OBJECTIVES

The aims of this mixed method systematic review were to (1) determine the characteristics and features of sports schools; (2) identify the methods used to evaluate sports school impacts, and (3) evaluate the positive and negative holistic athlete development impacts associated with sports school programme involvement.

METHODS

Adhering to PRISMA guidelines, eight electronic databases were searched until the final return in February 2021. Forty-six articles satisfied the inclusion criteria, were analysed thematically, and synthesised using a narrative approach. The methodological quality of included studies was assessed using the Mixed Methods Appraisal Tool.

RESULTS

Findings indicated (1) sports school student-athletes receive considerable support in terms of academic and athletic services, more intensified training and competition schedules with high-level training partners, but regularly miss school; (2) multiple methods have been used to evaluate student-athlete impacts, making comparison across studies and developing consensus on the impacts of sports schools difficult; and (3) there are a multitude of immediate, short- and long-term positive and negative impacts associated with the academic/vocational, athletic/physical, psychosocial and psychological development of sports school student-athletes.

CONCLUSIONS

This study is the first to systematically review the research literature to understand the impacts associated with sports schools in terms of holistic athlete development. Practitioners should be aware that they can promote (positive) and negate (negative) health impacts through the design of an appropriate learning environment that simultaneously balances multiple training, academic, psychosocial and psychological factors that can be challenging for youth athletes. We recommend that practitioners aim to design and implement monitoring and evaluation tools that assess the holistic development of student-athletes within their sports schools to ensure they are promoting all-round and healthy youth athlete development.

Statistical analysis considerations within longitudinal studies of physical qualities in youth athletes: A qualitative systematic methodological review

Background

The evaluation of physical qualities in talent identification and development systems is vital and commonplace in supporting youth athletes towards elite sport. However, the complex and dynamic development of physical qualities in addition to temporal challenges associated with the research design, such as unstructured data collection and missing data, requires appropriate statistical methods to be applied in research to optimise the understanding and knowledge of long-term physical development.

Aim

To collate and evaluate the application of methodological and statistical methods used in studies investigating the development of physical qualities within youth athletes.

Methods

Electronic databases were systematically searched form the earliest record to June 2021 and reference lists were hand searched in accordance with the PRISMA guidelines. Studies were included if they tested physical qualities over a minimum of 3 timepoints, were observational in nature and used youth sporting populations.

Results

Forty articles met the inclusion criteria. The statistical analysis methods applied were qualitatively assessed against the theoretical underpinnings (i.e. multidimensional development, non-linear change and between and within athlete change) and temporal challenges (i.e. time variant and invariant variables, missing data, treatment of time and repeated measures) encountered with longitudinal physical testing research. Multilevel models were implemented most frequently (50%) and the most appropriately used statistical analysis method when qualitatively compared against the longitudinal challenges. Independent groups ANOVA, MANOVA and X2 were also used, yet failed to address any of the challenges posed within longitudinal physical testing research.

Conclusions

This methodological review identified the statistical methods currently employed within longitudinal physical testing research and addressed the theoretical and temporal challenges faced in longitudinal physical testing research with varying success. The findings can be used to support the selection of statistical methods when evaluating the development of youth athletes through the consideration of the challenges presented.

The Effect of Three-Year Swim Training on Cardio-Respiratory Fitness and Selected Somatic Features of Prepubertal Boys

The data regarding somatic and physiological effects of sport-related physical activities in youth are limited. Moreover, whether exercise training is capable of increasing cardio-respiratory fitness remains a disputable issue. The study undertook to assess the effect of swimming training on cardio-respiratory fitness (CRF) and the development of physical traits in prepubertal boys, and to determine which of the traits is the best predictor of their CRF. Forty 10-year old prepubertal boys (10.5 ± 0.3 y) were divided into two groups (swimmers (SG), n = 20, and controls (CG), n = 20), which underwent anthropometric measurements and performed a 20 m shuttle run test (20 mSRT) semi-annually over a 3-year period. CRF indices (the number of 20 mSRT shuttles, maximal speed, and VO2max) were higher overall in the SG compared with the CG (p < 0.001). The values of the main physique variables increased faster in the CG, but the groups showed no differentiation of physical traits. In both groups, CRF indices were associated with the participants’ physical traits, the most strongly with the sum of four skinfold thicknesses in the SG and knee breadth in the CG. These results suggest that swimming training is a form of additional physical activity that improves prepubertal boys’ CRF but does not significantly affect their physical development. In using the 20 mSRT to assess the CRF of prepubertal boys, their physical activity level and age-related changes in body fatness need to be considered.

Substantial but Misunderstood Human Sexual Dimorphism Results Mainly From Sexual Selection on Males and Natural Selection on Females

Human sexual dimorphism has been widely misunderstood. A large literature has underestimated the effect of differences in body composition and the role of male contest competition for mates. It is often assumed that sexually dimorphic traits reflect a history of sexual selection, but natural selection frequently builds different phenotypes in males and females. The relatively small sex difference in stature (∼7%) and its decrease during human evolution have been widely presumed to indicate decreased male contest competition for mates. However, females likely increased in stature relative to males in order to successfully deliver large-brained neonates through a bipedally-adapted pelvis. Despite the relatively small differences in stature and body mass (∼16%), there are marked sex differences in body composition. Across multiple samples from groups with different nutrition, males typically have 36% more lean body mass, 65% more muscle mass, and 72% more arm muscle than women, yielding parallel sex differences in strength. These sex differences in muscle and strength are comparable to those seen in primates where sexual selection, arising from aggressive male mating competition, has produced high levels of dimorphism. Body fat percentage shows a reverse pattern, with females having ∼1.6 times more than males and depositing that fat in different body regions than males. We argue that these sex differences in adipose arise mainly from natural selection on women to accumulate neurodevelopmental resources.

Changes in Body Composition and Anthropomorphic Measurements in Children Participating in Swimming and Non-Swimming Activities

BACKGROUND

Physical activity is a well-known means of obesity prevention, but the relationship between exercise frequency and body composition in children has not been thoroughly investigated.

OBJECTIVE

The aim of this study was to compare the body composition of children aged 11-12 who regularly performed swimming and other sports as an organized extra-curricular physical activity for a 12-week period.

METHODS

The study included 46 students who attended swimming classes and 42 students who participated in training activities in other sports, including, but not limited to, football, basketball and athletics. Body height and body composition were measured using a Tanita BC 418 MA analyzer. The students individually reported their rate of perceived exertion during training using the Pictorial Children's Effort Rating Table PCERT scale.

RESULTS

The weekly volume of training was substantially higher in the group of swimmers than in that playing other sports (12.3 h/week vs. 5.2 h/week, p < 0.01). After 12 weeks of training, body height and weight significantly increased in both groups (p < 0.001). However, the BMI value and adipose tissue content only increased in the group of non-swimmers. Swimmers perceived greater exertion during training than non-swimmers (7.1 vs. 5.8 on the PCERT scale, p < 0.01).

CONCLUSIONS

In early pubescent children, engaging in vigorous exercise such as swimming for at least 10 h a week may restrain the growth of adipose tissue. However, the variety of exercises that are typical of team sports, if performed for no more than 5 h a week, may be insufficient to restrain adipose tissue growth.

Growth and maturity status of young male table tennis players

A maturity-associated gradient among adolescent athletes in many sports tends to favour early maturing participants. This study was aimed to describe inter-individual variance in growth and skeletal maturation among male youth table tennis. The sample included 99 players registered in competitive clubs for at least 2 years. Chronological age (CA) ranged 10.00-14.63 years. Stature and body mass were plotted relative to US references. Skeletal age (SA) was estimated with the Fels method. Maturity status was given as SA minus CA. Somatic maturation was derived from predicted age at peak height velocity. Mean values for stature and weight were above the reference medians from 10 to 13 years and at the median in the oldest group. In general, SA was in advance to CA (CA: 12.45 ± 1.28 years; SA: 13.44 ± 2.37 years). The majority of the players were early maturing according to SA (52%) and average maturing based on the somatic indicator (80%). The results suggested that table tennis tends to retain taller and heavier participants who are somewhat advanced in skeletal maturity. Participation in youth table tennis and opportunities to win need to consider age- and maturity-associated variations, particularly regarding bands for competitions.