Overweight/Obese Schoolchildren with Low Muscle Strength Have a Lower Cardiorespiratory Capacity and Greater Cardiovascular Risk: Results of the School Health Survey of the Extreme South of Chile 2019

Protocol Study: Resistance Training Program, Nutritional, Sleep, and Screen Use Recommendations in Schoolchildren from Educational Centers in the Extreme South of Chile

BACKGROUND

Childhood obesity has tripled, reaching critical levels of malnutrition. This factor is directly associated with a poorer health-related quality of life of the child and adolescent population. This article presents the study protocol of the project "Strong schoolchildren with a healthy lifestyle" (EF-Salud), which seeks to analyze the effects of a multicomponent program based on muscle strength exercises, sleep nutritional recommendations, and the use of screens in Chilean educational centers with extremely cold weather.

METHODS

The study protocol of a randomized controlled trial with a pre- and post-test conducted according to the CONSORT statement is reported. The total sample (n = 144) will be schoolchildren from six different school years, four of which will perform an intervention and two control. Intervention group 1 (from two different school years) will receive a muscular strength exercise program in the classroom once a day from Monday to Friday for six months and nutritional, sleep, and use of screens recommendations once a week. Intervention group 2 (from two different school years) will receive a program of nutritional, sleep, and use of screens recommendations once per week for six months. The control group (from two different school years) will carry out their usual school day in relation to physical education classes. Before and after the intervention, the investigators will evaluate the cardiovascular risk, physical condition, and lifestyle related to sleep and use of screens.

EXPECTED RESULTS

The schoolchildren in intervention group 1 will obtain significant results in increased strength, decreased cardiovascular risk, improved sleep habits, and fewer hours of screen use compared to the other two groups.

Feasibility and Reliability of Health-Related Physical Fitness Tests in Children and Adolescents with Hearing Impairment

Although research supports the feasibility and reliability of health-related physical fitness (HRPF) tests in typically developing children and adolescents, little is known regarding the feasibility and reliability of these tests for those with hearing impairments (HI). The aim of this study was to evaluate the feasibility and reliability of a HRPF test battery for children and adolescents with HI. A test-retest design with a one-week interval was conducted with 26 participants with HI (mean age: 12.7 ± 2.8 years; 9 male). The feasibility and reliability of seven field-based HRPF tests (i.e., body mass index, grip strength, standing long jump, vital capacity, long distance run, sit-and-reach, one leg stand) were evaluated. All the tests showed high feasibility (completion rate > 90%). Six tests indicated good to excellent test-retest reliability (all intraclass correlation coefficient [ICC] > 0.75) while the one leg stand test showed poor reliability (ICC = 0.36). Relatively large percentages of standard error of measurement (SEM%) and minimal detectable change (MDC%) were observed in the sit-and-reach test (SEM% = 52.4%, MDC% = 145.2%) and one leg stand test (SEM% = 107.9%, MDC% = 299.2%), whereas the rest of the tests demonstrated reasonable SEM% and MDC% values. Collectively, most of the tests can be feasibly and reliably used to assess HRPF for children and adolescents with HI.

Physical Fitness, Screen Time and Sleep Habits According to Obesity Levels in Schoolchildren: Findings from the Health Survey of the Extreme South of Chile

Obesity is a worry because it is associated with a greater burden of disease, and it has been shown to be related to the health habits and physical condition of children and adolescents.

OBJECTIVE

To associate physical fitness, screen time, and sleep habits with the different categories of obesity in schoolchildren from the extreme south of Chile.

METHODS

583 schoolchildren were included in this cross-sectional analysis. The screen time and sleep habits were measured with the Sleep Self-Report questionnaire, while the physical fitness was assessed with the Alpha Fitness test battery. The Body Mass Index/age (BMI/age) and the Waist-to-Height ratio (WtHr) were used to define adiposity using the following categories: healthy weight/low-risk waist-to-height ratio (H/LR), healthy weight/high-risk waist-to-height ratio (H/HR), overweight/low-risk waist to height ratio (O/LR), and overweight/high-risk waist to height ratio (O/HR).

RESULTS

A considerable number of schoolchildren (23.2%) presented sleep problems, while the mean screen time was 9.3 (95% CI: 8.4; 10.1) hours/day. Schoolchildren classified as H/HR showed better physical fitness than the O/HR group but worse physical fitness than the H/LR group.

CONCLUSIONS

Significant differences were evidenced in the physical fitness between the adiposity categories, which could open future lines of research concerning the characterization of the healthy weight-obese adiposity categories in children.

School-Based Comprehensive Strength Training Interventions to Improve Muscular Fitness and Perceived Physical Competence in Chinese Male Adolescents

Purpose. This research was to see how effective and feasible school-based comprehensive strength training programs are in improving muscular fitness and perceived physical competence in Chinese male adolescents. Methods. A total of 123 participants ( $13.46\pm 0.60$ years) were randomized to comprehensive strength training intervention group (CST) ( $n=62$ ) and the control group (CON) ( $n=61$ ). The training sessions were performed three times a week for ten weeks in CST. Muscular fitness (i.e., muscular strength, power, and muscular endurance) and perceived physical competence were assessed at initial testing and final testing. Results.The subjects in the CST significantly improved their mean performance in standing long jump ( $p<0.05$ ), vertical jump ( $p<0.05$ ), 1 min push-ups ( $p<0.05$ ), 1 min sit-ups ( $p<0.05$ ), handgrip strength ( $p<0.05$ ), and perceived physical competence ( $p<0.05$ ) after the intervention. Moreover, the CST were greater in standing long jump ( $p<0.05$ ), vertical jump ( $p<0.05$ ), 1 min sit-ups ( $p<0.05$ ), handgrip strength ( $p<0.05$ ), and perceived physical competence ( $p<0.05$ ) compared to the CON, but no in 1 min push-ups ( $p>0.05$ ). Conclusions. The comprehensive strength training interventions designed in this study can significantly increase male adolescents’ muscular fitness, especially in the lower extremity muscle power and abdominal core endurance, and can enhance their perceived physical competence.

Association of Physical Fitness, Screen Time, and Sleep Hygiene According to the Waist-to-Height Ratio in Children and Adolescents from the Extreme South of Chile

OBJECTIVE

To analyze the perception of physical fitness, screen time, and self-reported sleep hygiene in children and adolescents (CA) from the extreme south of Chile and its associations with waist-to-height ratio (WtHr).

MATERIAL AND METHODS

An observational cross-sectional study was conducted in a sample of 594 schoolchildren from 5th to 8th grade of primary education, belonging to municipal educational establishments in the Magallanes region, Chile. Cardiorespiratory fitness was assessed through the 20-m shuttle run test, muscle strength through handgrip and the standing broad jump test, physical fitness perception through the International Fitness Scale, and central obesity through the waist-to-height index. In addition, sleep hygiene and screen time were measured.

RESULTS

More than 92% of CA spent more than two hours a day watching or using screens. In addition, CA with excess central adiposity had a lower perception of physical fitness, and lower muscle strength and cardiorespiratory fitness compared to CA with normal values of adiposity.

CONCLUSIONS

CA of the present study spent a high number of hours watching or using screens and had poor sleep quality. In addition, excessive central adiposity was associated with lower physical fitness.

Physical Illiteracy and Obesity Barrier: How Physical Education Can Overpass Potential Adverse Effects? A Narrative Review

Environments lacking in stimuli together with ineffective physical education programs can lead to motor illiteracy, causing several adverse effects that could be worsened by unhealthy weight conditions (e.g., obesity). Obesity can be seen as an actual barrier for children and adolescents, especially for affective, behavioral, physical, and cognitive domains. In this context, condensing what the literature proposes could be useful in order to improve the understanding of the best intervention strategies (i.e., proper physical education programs) to manage the adverse effects of motor illiteracy in relation to the obesity barrier. The purpose of this narrative review is to improve the understanding on how physical education programs can counteract the adverse effects of physical illiteracy and obesity barrier across childhood and adolescence. Proper physical education programs should develop motor competence by fostering an individual’s awareness, self-perception, autonomous motivation, and muscular fitness on a realistic scenario (functional task difficulty related to his/her possibilities) in the attempt to counteract the adverse effects of the obesity barrier. Such programs should be designed without overlooking a proper multi teaching style approach.