Bilateral difference between lower limbs in children practicing laterally dominant vs. non-laterally dominant sports.

Bilateral asymmetry in lower-limb power and dynamic balance has been associated with increased risk of sport injury, whereas there is a lack of research examining this asymmetry for child athletes. Twenty-eight fencers (19 boys and 9 girls, aged 9.71 ± 1.08 years) and 28 Taekwondo athletes (19 boys and 9 girls, aged 9.71 ± 1.08 years) were examined on the single-leg jump and Star Excursion Balance Test (SEBT) performance. A mixed model design ANOVA (2 [Sex: Boys, Girls] × 2 [Sport group: Fencing, Taekwondo] × 2 [Limb: Dominant, Non-dominant Leg]) was conducted to examine for difference for each test. There was a significant main effect of limb on hop and triple hop distance (p < 0.05). A significant limb by sex interaction (p = 0.000) was shown for the single-leg countermovement jump (CMJ) performance, wherein a bilateral difference was only shown in boys. In SEBT, a main effect (p = 0.007) of limb was identified for posterolateral (PL) reach distance. A limb by sex interaction (p = 0.009) was also shown for posteromedial (PM) reach distance, wherein a bilateral difference was only shown in girls. These findings suggest that child athletes in both laterally dominant and non-laterally dominant sports showed inter-limb asymmetry of leg power and dynamic balance. Sex should be an important consideration when evaluating bilateral difference of leg power and dynamic balance for child athletes.

Bone Mineral Density and Sports Participation.

The objective of our study was to identify differences in bone mineral density (BMD) according to different sports among adolescents, as well as to identify assessments of relevant mediators. The sample consisted of 429 adolescents with a mean age of 13.3 ± 1.7 yr. The sports modalities that we evaluated were judo, karate, kung fu, swimming, basketball, and soccer. Nonsports group was composed of 111 adolescents. Bone density was assessed using dual-energy X-ray absorptiometry. Regarding BMD values, female engaged in karate had higher BMD values than girls from the no sports group (p = 0.01). Boys engaged in soccer and karate presented the highest BMD values than all the other groups (p = 0.01). The most relevant mediators were the body mass index and lean soft tissue for boys and girls. Different sports presented different results regarding BMD gains, which were influenced by body mass index and whole-body lean soft tissue.

[The comprehensive approach to the rehabilitative treatment of junior athletes]. / Kompleksnyi podkhod k vosstanovitel'nomu lecheniyu sportsmenov-yuniorov.

AIM: The objective of the present study was the development of the comprehensive program for the medico-psychological follow-up of the male and female junior athletes (rhythmic gymnastics) with the purpose of stabilizing their hormonal and emotional status, as well as improving sport performances based on the use of modern hardware-software technologies. MATERIAL AND METHODS: The comprehensive examination of 72 female athletes at the mean age of 11.5±0.6 years attending R. Kuznetsov specialized school of rhythmic gymnastics of the Olympic reserve in the city of Seversk has been undertaken on the basis of Tomsk Research Institute of Balneology and Physiotherapy, the branch of Siberian Federal Research and Clinical Centre. RESULTS: The program of comprehensive medical psychological rehabilitation for the junior athletes of either sex engaged in sportive activities requiring precise technical actions has been elaborated. The method of the combined therapeutic treatment included physical exercises therapy, manual massage, dry carbonic bathtubs, psychological activities with the application of biological feedback trainings and cognitive trainings; it was intended for the correction of the hormonal status and the improvement of the psycho-emotional conditions of the athletes. The combined treatment based on the use of the modern hardware-software technologies was shown to promote the restoration and development of the psychophysical and psychological qualities of the male and female junior athletes indispensable for the maintenance of their high readiness for the efficient sports activities at the subsequent stages of the training cycle. In addition, such treatment enhances the adaptation resources of the athletes.

Beta-Alanine Supplementation Improves Throwing Velocities in Repeated Sprint Ability and 200-m Swimming Performance in Young Water Polo Players.

The purpose of this study was to investigate the effects of beta-alanine supplementation on specific tests for water polo. Fifteen young water polo players (16 ± 2 years) underwent a 200-m swimming performance, repeated-sprint ability test (RSA) with free throw (shooting), and 30-s maximal tethered eggbeater kicks. Participants were randomly allocated into two groups (placebo × beta-alanine) and supplemented with 6.4g∙day-1of beta-alanine or a placebo for six weeks. The mean and total RSA times, the magnitude based inference analysis showed a likely beneficial effect for beta-alanine supplementation (both). The ball velocity measured in the throwing performance after each sprint in the RSA presented a very like beneficial inference in the beta-alanine group for mean (96.4%) and percentage decrement of ball velocity (92.5%, likely beneficial). Furthermore, the percentage change for mean ball velocity was different between groups (beta-alanine=+2.5% and placebo=-3.5%; p = .034). In the 30-s maximal tethered eggbeater kicks the placebo group presented decreased peak force, mean force, and fatigue index, while the beta-alanine group maintained performance in mean force (44.1%, possibly beneficial), only presenting decreases in peak force. The 200-m swimming performance showed a possibly beneficial effect (68.7%). Six weeks of beta-alanine supplementation was effective for improving ball velocity shooting in the RSA, maintaining performance in the 30-s test, and providing possibly beneficial effects in the 200-m swimming performance.

Physical activity interventions to promote positive youth development among indigenous youth: a RE-AIM review.

Physical activity (PA) programs are a promising strategy to promote positive youth development (PYD). It is not known if published reports provide sufficient information to promote the implementation of effective PYD in indigenous youth. The purpose of this study was to assess the extent to which published literature on PA programs that promote PYD in indigenous youth report on RE-AIM (reach, effectiveness, adoption, implementation, maintenance) indicators. A systematic literature search was conducted to identify articles reporting on PA programs that promote PYD in indigenous youth. The search yielded 8084 articles. A validated 21-item RE-AIM abstraction tool assessing internal and external validity factors was used to extract data from 10 articles meeting eligibility criteria. The most commonly reported dimensions were effectiveness (73 %), adoption (48 %), and maintenance (43 %). Reach (34 %) and implementation (30 %) were less often reported. Published research provides insufficient information to inform real-world implementation of PA programs to promote PYD in indigenous youth.