Effects of different aerobic exercise training on glycemia in patients with type 2 diabetes: A protocol for systematic review and meta analysis.

BACKGROUND: Type 2 diabetes is an emergent worldwide health crisis, and rates are growing globally. Aerobic exercise is an essential measure for patients with diabetes, which has the advantages of flexible time and low cost. Aerobic exercise is a popular method to reduce blood glucose. Due to the lack of randomized trials to compare the effects of various aerobic exercises, it is difficult to judge the relative efficacy. Therefore, we intend to conduct a network meta-analysis to evaluate these aerobic exercises. METHODS: According to the retrieval strategies, randomized controlled trials on different aerobic exercise training will be obtained from China National Knowledge Infrastructure, WanFang, SinoMed, PubMed, Web of Science, EMBASE, and Cochrane Library, regardless of publication date or language. Studies were screened based on inclusion and exclusion criteria, and the Cochrane risk bias assessment tool will be used to evaluate the quality of the literature. The network meta-analysis will be performed in Markov Chain Monte Carlo method and carried out with Stata14 and OpenBUGS software. Ultimately, the evidentiary grade for the results will be evaluated. RESULTS: Eighteen literatures with a total of 1134 patients were included for the meta-analysis. In glycemia assessment, Tennis (standard mean difference = 3.59, credible interval 1.52, 5.65), had significantly better effects than the named control group. Tennis (standard mean difference = 3.50, credible interval 1.05, 5.59), had significantly better effects than the named Taiji group. CONCLUSION: All together, these results suggest that tennis may be the best way to improve blood glucose in patients with type 2 diabetes. This study may provide an excellent resource for future control glycemia and may also serve as a springboard for creative undertakings as yet unknown.

The Winning Probability of a Game and the Importance of Points in Tennis Matches.

Purpose: This study builds a stochastic model of a discrete-time Markov chain (DTMC) that fits well with a dataset of professional playing records. Methods: The point-by-point dataset of Men's single matches played in the Association of Tennis Professionals (ATP) tour from 2011 to 2015 is analyzed. A long-debated assumption on the iid-ness in the point winning probability of the server is statistically tested. A DTMC model is then developed to analyze the dataset further. Results: The statistical test results indicate that the identicality of point winning probabilities is not a valid assumption. For example, the server's point winning probability from scores 40:0, 30:15, 15:30, and 0:40 are significantly different. On the other hand, the independence is a generally valid assumption except for 40:15 where who won the previous point influences the point winning probability. Game winning probabilities and the importance of each point in winning a game are analyzed using the DTMC model by court surfaces and player groups of the different levels of serve effectiveness. Conclusion: Extensive empirical validation concludes unsealed debates over the stochastic models for tennis. The presented results reveal interesting properties in professional tennis matches.

Rankings in professional men's tennis: a rich but underutilized source of information.

Success in professional tennis is measured, at least in part, by rankings. However, there is little quantitative evidence to inform stakeholders regarding what represents the typical ranking progress of top-ranked players. The objective of this study was therefore to compare the ranking trajectories of male players whom achieved peak professional rankings in the Top 250, 175, 100, 50, 20 and 10. The 11,396 birthdates and weekly professional rankings of all players between 27 August 1973 and 31 October 2011 were collated. The peak ranks for each athlete according to their both chronological age and number of years on tour were identified and athletes were categorised into one of six career-peak ranking bands. One-way analysis of variance tests confirmed distinctive ranking trajectories, which were most pronounced among Top 10 players. The rankings of these players were statistically distinguishable following players' second year on tour or by 17 years of age. The ranking signature of all Top 100 players emerged as significantly different to players that failed to enter the Top 100 by their fourth year on the tour. Indeed, the representation of ranking as a function of years on tour should be considered for use by tennis policy-makers in the future.

Ultrasound assessment of asymmetric hypertrophy of the rectus abdominis muscle and prevalence of associated injury in professional tennis players.

OBJECTIVE: To assess rectus abdominis (RA) thickness and injury prevalence using ultrasound in a group of professional tennis players. Observations with regard to muscle fiber repair is described. We likewise studied the potential link between RA volume asymmetry and the risk of muscle strain. MATERIALS AND METHODS: The degree of asymmetry between the different RA slices was assessed using ultrasound in 61 professional tennis players. The history of RA injury in these tennis players was likewise studied, taking into account the following factors: dominant vs non-dominant arm, history of RA strains, duration thereof and number of recurrences. Ultrasound examination was performed with an 8- to 12-MHz linear multi-frequency transducer. RESULTS: Ultrasound revealed the presence of fibrous scar tissue in the RA muscle in 18 cases (29.5%). In all instances, the lesion was located in the RA on the side of the nondominant arm. In 16 of the cases, the lesion was infra-umbilical and L2 was affected in two cases. The mean maximum width of the fibrous repair tissue was 9 mm (range 5-16). The mean distance between the umbilicus and the scar was 5.8 cm (range 2.9-11.4). Statistical study of the ultrasound measurements obtained for the different slices revealed statistically significant differences between the different depths and according to arm dominance. CONCLUSIONS: In the series studied, the prevalence of RA muscle lesion in professional tennis players was 29.5%. Asymmetric hypertrophy of the RA muscle appears to constitute a risk factor for suffering an injury in this location.

Avaliação das lesões ortopédicas em tenistas amadores competitivos / Assessment of orthopedic injuries in competitive amateur tennis players

Estudar a incidência de lesões ortopédicas, em tenistas competitivos. Material e métodos: Por meio da análise retrospectiva, 160 tenistas amadores, mas competitivos, do Estado de São Paulo foram estudados. Destes, 64 (40 por cento) eram do sexo feminino e 96 (60 por cento) do masculino. A idade variou de nove a 78 anos, com média de 27,6 anos. Para a análise do material com relação ao número de lesões e ao tipo de lesão apresentada, empregaram-se os critérios da NAIRS (National Athletic Injury Report System) e, para a análise estatística dos dados, utilizou-se o teste t de Student para amostras pareadas, estabelecendo como valor de significância o índice de probabilidade (p) menor do que 0,05. Resultado: Foram relatadas 244 lesões em 122 atletas. Somente 38 (23,8 por cento) tenistas não referiram nenhum tipo de lesão durante a sua vida competitiva. Com relação à região do corpo acometida, a lesão mais freqüente foi a muscular, relatada por 58 (23,8 por cento) tenistas. Logo a seguir foram relatadas as lesões do pé e tornozelo (48-19,7por cento tenistas) e cotovelo (41 - 16,8 por cento - atletas). As patologias específicas mais freqüentemente relatadas foram a epicondilite lateral do cotovelo (epicondilite), relatada por 38 atletas, e as torções do tornozelo (36 relatos). Em média, os tenistas afastaram-se dos treinos e jogos por cinco semanas e quatro dias, porém, este afastamento variou de acordo com o local do organismo acometido pela lesão. As lesões que determinaram maior afastamento das quadras foram as intra-articulares do joelho. Dos atletas que tiveram lesão no joelho, 53,8 por cento submeteram-se a cirurgia e se afastaram do esporte pelo menos por três meses. Conclusões: No tênis, as lesões musculares foram as mais freqüentes, porém, as lesões traumáticas do joelho se mostraram as mais graves e determinaram maior tempo de afastamento das quadras. Não houve diferença estatisticamente significante entre o maior número de torneios disputados ao ano e a maior incidência de lesões. Com relação à epicondilite, na população estudada, não houve diferença estatística entre maior tensão utilizada nas cordas da raquete com a maior incidência da lesão, porém, observou-se que tempo maior de prática do esporte predispõe à lesão. Técnica correta de movimentos básicos parece ser o melhor fator preventivo da epicondilite

Elite athletes' sensitivity to context: the case of a change in scoring system in table tennis.

3 elite table tennis players' streams of actions during international matches were compared under the old scoring system (3 winning sets of 21 points) and the new (4 winning sets of 11 points). The organization of actions changed under the new system, with the relative duration of exploration activity becoming shorter than that of execution activity. These results indicate that elite performance in table tennis is characterized by the athletes' close attunement to elements of context--in this case, the scoring system--for the organization of their actions.