Understanding the prevalence and trends of obesity in preschool children is of critical importance for public health policy. Thus, the object of the present study was to assess the prevalence and trends of obesity in Chinese preschool children from 1996 to 2019, and to examine the differences among different population according to year, gender, age, urban/rural and geographical area.
Four online databases (Chinese National Knowledge Infrastructure, Wanfang Data Resource System, Weipu Chinese Journal Service Platform and PubMed) were searched for studies published from January 1990 to May 2019 using predefined inclusion/exclusion criteria. Random effects meta-analysis was used to calculate the prevalence of obesity.
Forty-three studies with a total of 765,255 Chinese preschool children aged 3–6 years were included in this meta-analysis. The prevalence of obesity in the whole sample was 6.41% (95%CI: 5.74%–7.78%, P < 0.000, I 2 = 99.79%; obtained after trim-and-fill adjustment). There was no significant difference (P = 0.222) in the prevalence of obesity during five periods (1996–2000, 2001–2005, 2006–2010, 2011–2015, 2016–2019). The obesity prevalence of boys was higher than girls (P = 0.007), and the obesity prevalence increased with age (P = 0.000). In 2006–2010, the prevalence of obesity among urban areas was about three times than that of rural areas (P = 0.001). However, the difference was decreased during 2011–2015 (P = 0.788). In rural areas, the obesity prevalence in 2011–2015 was two times more than that in 2006–2010 (P = 0.005). Geographical area was a strong determinant of heterogeneity for Chinese preschool children (P = 0.001).
There was no significant difference of the obesity prevalence among any five-year periods from 1996 to 2019. The prevalence of obesity in boys was higher than girls and increased with age. Though the prevalence of obesity in rural area was lower than the urban area, the speed of the increasing of the prevalence after 2010 in rural area should be noted. Public health intervention such as physical activity promotion and nutrition education should be conducted on preschool children for obesity prevention to promote their healthy development.
The purpose of this meta-analysis was to evaluate the effects of acute exercise on short-term memory improvement. The computerized literature searches using electronic databases and examinations of reference lists from relevant studies yielded six studies meeting our inclusionary criteria. In a total of six studies, 16 standardized regression coefficient effect sizes (ESs) were calculated to be meta-analyzed. The meta-analyses showed a statistically significant increase in short-term memory improvement across both the exercise and non-exercise control groups in trials 1–5 [ES = 0.96, 95% CI (0.95, 0.97), P < 0.001]. However, there was no significant subgroup difference between exercise and control groups (Q b = 0.40, df = 1, P = 0.53). Our meta-analytic review provides suggestive evidence that an acute bout of exercise prior to learning does not result in short-term memory improvement to a greater extent than a non-exercise control. Additional research is needed to further evaluate whether acute exercise enhances long-term memory via enhanced learning and/or post-learning mechanisms.
Using an ActiGraph GT3X+ accelerometer, the study examined the effects of different epoch lengths on children’s moderate to vigorous physical activity (MVPA). The study also tested how different MVPA levels influence the relationship between epoch length and MVPA. The participants included third (n = 28) and fourth grade (n = 35) students. The third graders participated in a physical education class while the fourth graders were engaged in an active video game (AVG) class. Data were downloaded using six different epoch lengths. MVPA estimates were determined by five different cut points. Multi-level analyses were used to analyze the data. Results showed that when lower cut points were used, MVPA was positively related to epoch lengths, and this relationship was stronger when the MVPA level was higher. When higher cut points were used, epoch length was negatively related to MVPA, and this relationship was stronger when the MVPA level was lower. This study revealed that different epoch lengths generate various estimates of MVPA, and the relationship between epoch length and MVPA is affected by MVPA levels.
Understanding the desired attributes for talented soccer players may give insight into the process of (de)selection and player development. This study aimed to explore soccer academy personnel’s perceptions of attributes associated with talent and development.
Thirty English and Scottish academy personnel (managers, coaches, recruitment, sports scientists) provided perceptions into what attributes contribute to ‘talent’, via an online survey. Utilising an E-Delphi method, seven experts refined these inputs over several rounds until a consensus was reached, resulting in 82 agreed terminology. This terminology was resubmitted via a second online survey, where 45 academy personnel rated each using a Likert scale.
A ranking of attributes by importance was produced, finding Psychological and Technical/Tactical attributes considered of greatest importance. Differences were observed, whereby recruitment personnel consistently over-emphasised the importance of several attributes compared to other personnel (P = 0.02–0.04). When analyzed within each age phase, 11 variations in the perceived importance of attributes were demonstrated in the youth phase (11–16 years, P = 0.01) compared with 5 in the professional phases (17–23 years, P = 0.01–0.05)
The present study demonstrates that ‘talent’ requires multifaceted developments, with academy personnel perceiving psychological attributes the most important contributor to development
Genetic research in football is currently in it’s infancy but is growing rapidly. However, the practical application of genetic testing in football and the views concerning its use are unknown. Thus, the purpose of this study was to assess the current practical application of genetic testing in professional football and provide an insight into the perspectives of key stakeholders (i.e., coaches, practitioners, players).
In total, 122 participants completed an online anonymous survey. This consisted of 21 multiple choice and Likert scale questions, with the option of providing an explanation for each response.
Findings revealed genetic testing is rarely utilised by key stakeholders (10%) or their respective organisations (14%). However, three quarters (75%) had the opinion that genetic testing will have great utility in the future. The majority (72%) believed genetic testing should be used for athlete development and injury risk, whilst 35% believed that genetic testing should be utilised for talent identification purposes. However, most key stakeholders viewed their own (89%) and their colleagues’ (79%) knowledge related to genetic testing as insufficient; mainly due to ineffective current communication methods (91%). Most believed educational workshops are required (71%), whilst nearly all (91%) were interested in developing their expertise on the utility of genetic testing.
Genetic testing is rarely used within professional football, although key stakeholders anticipate that it will be utilised more in the future. As such, educational support may prove valuable in improving key stakeholder knowledge and the practical application of genetic testing in professional football.
Weight making behaviours and best practice recommendations for various combat sports have been well documented, however this is not true for Silat athletes. Pre- and post- weigh-in recommendations for other combat sports may not be suitable for Silat due to differences in weigh-in rules. Using a well-established questionnaire, this questionnaire-based cross sectional study examined weight making practices of Silat match athletes (n = 102) competing at a national Pencak Silat championship. The 24.5% of athletes engaged in pre-competition weight loss, and the overall Rapid Weight Loss Score (RWLS) was 27.7 ± 8.7, considerably lower than other combat sports. The median age when weight loss began was 17 years, with 32% (n = 8) starting such practices under 17 years. Risky weight management practices such as the use of laxatives, diet pills and vomiting were less common than in other combat sports. Coaches and fellow athletes are key influencers of weight making practices, and dietitians were found be an underutilised resource. Appropriate measures to empower coaches and athletes with the knowledge and ability to guide and execute less detrimental weight making practice with the involvement of dietitians are suggested. The study findings provide information to establish Silat-specific dietary strategies to improve health and performance.
To develop an understanding of the role of shoulder padding in rugby union by investigating player perceptions and attitudes towards shoulder padding and extending research into shoulder injuries in rugby.
An online survey was distributed to past and current rugby players over 13 years old in 2018. Questions related to the participants’ demographic, attitudes to shoulder padding and shoulder injury history.
Six hundred and sixteen rugby players responded to the survey; 66.1% of respondents had worn shoulder padding at some point. The age group 24–29 years old (∆R 2 = 0.03, B = − 0.53, P = 0.015) had an inverse association with padding effectiveness while playing experience groups 1–2 years (∆R 2 = 0.03, B = 0.8, P = 0.032), 3–5 years (∆R 2 = 0.03, B = 0.70, P = 0.002) and 6–9 years (∆R 2 = 0.03, B = 0.41, P = 0) had a positive association. There are 37.1% of respondents considering shoulder padding to be effective at preventing cuts and abrasions with 21.9% finding it very effective; 50.3% considered it to be effective or very effective (9.7%) at preventing contusion; 45.5% wore padding for injury prevention, while 19.2% wore padding to protect from reoccurring injury. Sprain/ligament damage (57.5%) and bruising (55.5%) were the most commonly reported injuries.
The primary reason for wearing shoulder padding was as a means of injury prevention. Research should focus on quantifying the injury preventive capabilities of shoulder padding. Bruising, cuts and abrasion injuries to the shoulder are prevalent presenting new findings that these injuries are underreported.
The kinetic profile of golf swings is frequently assessed in biomechanics. However, most research is limited to young golfers, so the mechanical demands on older athletes are poorly documented. This study provides kinetic data of older golfers swinging with a driver and a 6-iron.
We examined 17 older, skilled male golfers (62.2 ± 8.8 years, handicap 8.7 ± 4.9) using a 10-camera motion capture system and two force platforms. Three-dimensional net support moments, joint moments of the hip, knee, and ankle, ground reaction forces (GRF), and the inclination angles between the centre of mass (COM) and centre of pressure (COP) were calculated and tested for between-club differences.
The 3D net support moments of the trail leg were higher when using the driver, while those of the lead leg were higher with the 6-iron. Between-club differences existed in the relative contribution from each joint, the COM–COP inclination angles, and the peak GRF.
The mechanical demands of golf swings on older adults differ between a driver and a 6-iron, which likely affects the balance and control strategies required. This improved understanding of the kinetic profiles of golf swings in older adults provide clinicians and coaches better means to maintain older golfers active and healthy for longer.
Improving balance control in older adults is one of the main objectives of fall prevention programs, and tennis could represent a promising way to train balance control.
To verify whether older tennis players have similar reactive response characteristics to balance perturbations to those of healthy young people.
Fifteen young people (23.00 ± 1.96 years) and twelve older people (69.08 ± 3.82 years), remained in an orthostatic position, with their arms at their sides, on a force platform during ten mediolateral perturbations. The surface electromyography signal of the gluteus maximus, tibialis anterior, gastrocnemius lateralis, and vastus lateralis muscles was acquired on the dominant side.
The velocity and amplitude parameters of the center of pressure displacement were similar between the groups, as well as the amplitude of the electromyography signal of the tibialis anterior, vastus lateralis, and gastrocnemius lateralis muscles. There was a statistical difference between the groups in the gluteus maximus muscle in the first perturbation.
Older tennis players present similar center of pressure velocity performance and amplitude of center of pressure displacement behavior to young people. Older tennis players have an increased range of muscle activation, generating automatic postural responses adapted to deal with situations of balance perturbations.
The aim of this study was to investigate the anthropometric characteristics of elite taekwondo players based on weight categories, and to determine if the length of the lower extremities might influence player’s success-level. A total of 59 elite male taekwondo players (22.02 ± 3.07 years) participated in this study.
All anthropometric assessments were performed according to the standards and methodology of the International Society for Advancement of Kinanthropometry. The 18 anthropometrical variables were measured for each athlete and compared between 7 different weight categories. The players were also divided into two groups (national and international) and the ratios of sitting-height to stature were compared.
There were significant differences (P < 0.05) between weight divisions in stature, body mass index, percentage of body fat, endomorphy, and mesomorphy, which were greater (P < 0.05) in heavy weight groups than light weight groups, and ectomorphy, which was greater (P < 0.05) in very light weight groups compared with the other weights. There was no significant difference in lean mass index (P > 0.05) between weight groups. Sitting height/stature ratio was significantly different (P < 0.05) between the two groups, where the international group had longer lower extremities than the national group.
The findings of this study provide a valuable framework to support talent identification programmes and the development of specialised preparatory strategies for different weight divisions with the sport.