Plyometric training increases gross motor coordination and associated components of physical fitness in children

The Similarity Degree of the Anthropometric and Body Composition Variables of Brazilian and Mozambican Schoolchildren: A New Approach Using the Smoothed Jaccard Index Surface

BACKGROUND/OBJECTIVES

Brazil and Mozambique face similar socioeconomic challenges, including common indicators of undernutrition and overnutrition among children. This study evaluated the similarity degree of the anthropometric and body composition variables of Brazilian and Mozambican children by using the Jaccard index.

METHODS

A total of 1831 children of both genders aged 7-10 years from three Brazilian cities (Recife, Vitoria de Santo Antao, and Lagoa do Carro) and three Mozambican cities (Maputo, Boane, and Inhambane) participated in this study. Anthropometric (height, body mass, and waist circumference) and body composition (body fat percentage [%BF], lean mass, and fat mass) variables were measured and the Smoothed Jaccard Index Surface (SJIS) was used to evaluate the similarity degree.

RESULTS

Brazilian children were taller and heavier and had a higher %BF and fat mass than Mozambican children. Children living in urban areas were taller than those living in rural zones in both countries. Brazilian and Mozambican children showed high similarity only between %BF and lean mass. Children from Recife and Maputo had high similarities among waist circumference, body mass, fat mass, height, and %BF. Finally, a high SJIS degree was observed among height and %BF for schoolchildren from rural and urban zones.

CONCLUSION

Brazilian and Mozambican children exhibit differences in growth characteristics but a high degree of similarity when children from rural and urban zones are compared.

Effects of plyometric training on health-related physical fitness in untrained participants: a systematic review and meta-analysis

Plyometric training (PT) is an effective training method for improving physical fitness among trained individuals; however, its impact on health-related physical fitness in untrained participants remains ambiguous. Therefore, this meta-analysis aimed to evaluate the effects of PT on health-related physical fitness among untrained participants. Six electronic databases (PubMed, CINAHL Plus, MEDLINE Complete, Web of Science Core Collection, SCOPUS, and SPORTDiscus) were systematically searched until March 2024. We included controlled trials that examined the effects of PT on health-related physical fitness indices in untrained participants. Twenty-one studies were eligible, including a total of 1263 participants. Our analyses revealed small to moderate effects of PT on body mass index, muscular strength, cardiorespiratory fitness, and flexibility (ES = 0.27-0.61; all p > 0.05). However, no significant effects were detected for body fat percentage and lean mass (ES = 0.21-0.41; all p > 0.05). In conclusion, the findings suggest that PT may be potentially effective in improving health-related physical fitness indices (i.e., body mass index, muscular strength, cardiorespiratory fitness, and flexibility) in untrained participants. However, the results should be interpreted cautiously due to data limitations in some fitness variables.

Combined Physical Training Strategies Improve Physical Fitness, Behavior, and Social Skills of Autistic Children

The present study aimed to investigate the effects of combined physical training (CPT) on social skills and physical fitness (PF) in children with ASD. Sixteen children with autism (age 6-10 years) were randomly assigned into two groups: CPT and control. The CPT group participated in a program involving ball game, rhythmic movements, and resistance training for eight weeks (three sessions per week). PF and behavior profile were assessed before and after training. CPT program had a significant effect on indicators of social skills such as stereotypic behavior and communication, as well as PF such as handgrip strength, upper and lower body power, flexibility, balance, and agility (P < 0.05). CPT in autistic children can improve indicators of social skills and PF.

Daily consumption of ultra-processed foods and cardiometabolic risk factors in children aged 7 to 10 years in Northeast Brazil

Background: Ultra-processed foods (UPFs) consumption is associated with pediatric overweight and obesity. Aim: To evaluate the UPFs consumption in children classified either as eutrophic or with excess weight (overweight and obesity). It was also described the fasting plasma glucose, total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) and the correlation between UPFs consumption and cardiometabolic risk factors. Methods: A total of 139 children aged 7-10years of both sexes, living in Northeast Brazil were classified as eutrophic (n = 65) or excess weight (n = 62). Waist circumference (WC), percentage of body fatness (% BF), fat-free-mass and fat mass were evaluated. Fasting blood sample were collected for biochemical analysis. Food consumption was classified according to the degree of processing. Results: Children with excess weight had a reduction in plasma HDL concentration (45.00; IQR:36.00-54.50 mg/dL vs. 40.00; IQR:35.75-45.25 mg/dL; p = 0.021) and an increase in blood glucose (82.00; IQR:79.00-86.00 mg/dL vs. 86.00; IQR:81.00-90.00 mg/dL; p < 0.001) and TG (64.00; IQR:45.00-92.50 mg/dL vs. 81.00; IQR:57.50-111.75 mg/dL; p < 0.021) when compared with the eutrophic children. UPFs accounted for 43.43% of the total calories consumed by children. Children with excess weight had higher total energy consumption resulting from consumption of UPFs (714.30 ± 26.32 kcal vs. 848.06 ± 349.46 kcal; p = 0.011). The absolute consumption of the UPFs showed a positive correlation with WC (r = 0.202; p = 0.023) and %BF (r = 0.198; p = 0.026). Conclusion: UPFs consumption was higher for children with excess weight and positively correlated with two cardiometabolic risk factors, suggesting the need for strengthening public policies that discourage the consumption of these foods.

Motor Coordination in Children: A Comparison between Children Engaged in Multisport Activities and Swimming

Motor coordination has a crucial role in various physical activities and sports, highlighting its significance in overall movement proficiency and performance. This study aimed to compare motor coordination in children engaged in multisport versus swimming activities. The participants of this study included 180 boys and girls (girls = 87) aged 8.25 years ± 0.89. A total of three groups were included: group 1 consisted of inactive children, group 2 included children participating in swimming, and group 3 included children enrolled in multisport. Motor coordination was assessed using the Kiphard-Schilling body coordination test, evaluated by motor quotient (MQ): walking backwards, hopping for height, jumping sideways, and moving sideways. Additionally, a total motor quotient (Total MQ) was calculated based on the performance in all four tests. ANOVA revealed a significant difference in Total MQ and all subtests between the groups (p < 0.01). A significant difference in Total MQ was found not only between the inactive and multisport groups (Diff = 19.8000; 95%CI = 13.1848 to 26.4152; p = 0.001) but also between the multisport and swimming groups (Diff = 12.8000; 95%CI = 6.3456 to 19.2544; p = 0.001). In conclusion, the results revealed that children involved in multisport activities exhibited significantly better motor coordination compared to both the swimming group and the inactive group. Therefore, to enhance the growth of motor coordination abilities, it is crucial that parents, instructors, and coaches encourage kids to engage in multisport physical activities on a daily basis.

Influence of Strength Training Variables on Neuromuscular and Morphological Adaptations in Prepubertal Children: A Systematic Review

Strength training in prepubertal children is one of the topics that has aroused the most interest and controversy among training professionals in recent years. Therefore, the aim of the present study was to analyze the available scientific evidence on the influence of strength training variables on morphological and/or neuromuscular adaptations in healthy prepubertal populations with no previous experience in this type of training according to the descriptive sample characteristics. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis, 22 studies were selected after a systematic search and selection process using four electronic databases: Google Scholar, PubMed, Scopus, and SPORT Discus. Furthermore, the internal validity of the studies included was assessed using the modified PEDro scale. The sample consisted of 604 prepubertal children (age, 10.02 ± 0.75 years), of whom 473 were boys and 131 were girls, with 104 strength training programs recorded. Strength training resulted in a significant increase in jumping (n = 29) and sprinting (n = 13) abilities. Moreover, muscle strength was increased in 100% of the cases. Morphologically, strength training resulted in a decrease in body fat percentage (n = 19) and an increase in lean body mass (n = 17). With regard to gender, increases in general sport skills and basic physical abilities were significant in males but not in females. Thus, the results are more heterogeneous in girls due to the small number of studies carried out. Therefore, this research provides practical applications for coaches to design and implement more effective training programs to maximize adaptations, enhance physical performance, and reduce injury risk.

Relevance and Effectiveness of Combined Resistance and Balance Training to Improve Balance and Muscular Fitness in Healthy Youth and Youth Athletes: A Scoping Review

BACKGROUND

Balance and resistance training applied as single-mode interventions have proven to enhance measures of balance and/or muscular fitness in youth and youth athletes. Less is known on the effectiveness of combined or sequenced balance and resistance training in youth and youth athletes.

OBJECTIVE

The objective of this scoping review was to describe the effects of concurrently performed balance and resistance training (i.e., metastable resistance training) and different sequencing schemes of balance and resistance training on measures of balance and/or muscular fitness in healthy youth and youth athletes. We additionally aimed to identify knowledge gaps in the literature.

METHODS

According to the principles of a scoping review, we followed a broad research question, identified gaps in the literature, and reported findings on the level of single studies but did not aggregate and meta-analyze outcomes across studies. For this purpose, systematic literature searches were conducted in the electronic databases PubMed (including MEDLINE), Web of Science, and SPORTDiscus from inception until August 2022. We included metastable resistance training and sequenced balance and resistance training studies in healthy youth and youth athletes aged 6-18 years that investigated the training-induced effects on measures of balance (e.g., stork balance test) and muscular fitness (e.g., countermovement jump test) in contrast to active/passive controls. The Physiotherapy Evidence Database (PEDro) scale was used to assess the risk of bias. The Strength of Recommendation Taxonomy (SORT) was applied for the whole scoping review on levels A (high strength of recommendation) to C (low strength of recommendation) and for individual studies on levels 1 (high-quality evidence) to 3 (low-quality evidence).

RESULTS

The strength of recommendation for the scoping review was level B based on inconsistent or limited-quality evidence. Eleven randomized controlled trials were eligible to be included in this scoping review and each study was rated as 'limited-quality evidence'. A median PEDro score of 6 was computed across the included studies. Four studies examined the effects of metastable resistance training (e.g., plyometric training on unstable surfaces) on measures of balance and/or muscle fitness in youth athletes. The remaining seven studies investigated the impact of sequenced balance and resistance training (e.g., blocked balance training followed by blocked resistance training) on measures of balance and/or muscle fitness in youth and youth athletes. The duration of the intervention programs ranged from 6 to 10 weeks with 2-weekly to 3-weekly exercise sessions. Participants' age range was 10-18 years (mean 15 years). Ten studies examined young male and female athletes from different sports (i.e., basketball, handball, soccer) and one study physical education students. Metastable resistance training compared with plyometric training performed on stable surfaces showed no extra effect on measures of balance and muscular fitness. Stable plyometric training appears to be even more effective to improve jump performance. Sequenced balance and resistance training in the form of a mesocycle of balance followed by plyometric training seems to be particularly effective to improve measures of balance and muscular fitness in young athletes. This scoping review identified knowledge gaps that may indicate future research avenues: (i) comparative studies should be designed to examine how sex, age, maturity status, and expertise level impact on the adaptive potential following metastable resistance training or sequenced balance and resistance training in youth and youth athletes, (ii) at least one established measure of balance and muscular fitness should always be included in study designs to allow future comparison between studies and to aggregate (meta-analyze) findings across studies and (iii) studies are needed that examine neuromuscular and tendomuscular adaptations following these exercise types as well as dosage effects.

CONCLUSIONS

According to the results of this scoping review, balance training should be an essential training component for youth that is incorporated with the resistance training exercises or introduced at least a month before resistance and plyometric training within a periodized training program. More research is needed to examine the moderating roles of age, maturity status, and sex.

Effects of Four Weeks of Plyometric Training Performed in Different Training Surfaces on Physical Performances in School Children: Age and Sex Comparisons

Short- to middle-term plyometric training has been shown to be an effective method to promote youth fitness and health. However, there is no knowledge of previous studies that investigated the sex and age effects on physical fitness following different PT surfaces (i.e., firm vs. sand) in schoolchildren. This study examined the effects of age and sex on explosive and high-intensity responses following plyometric training (4 weeks, twice/week) performed on firm vs. sand surfaces in untrained schoolchildren. Ninety girls and ninety boys (under 8: age = 7.1 ± 0.5 and 7.1 ± 0.4 years; under 10: age = 9.0 ± 0.4 and 9.0 ± 0.5 years; under 12: age = 11.0 ± 0.5 and 11.0 ± 0.5 years, respectively) participated in a randomized and parallel training design with pre-to-post testing. Participants were allocated (i.e., 30 boys and 30 girls for each group) into either two experimental groups (firm group: performing plyometrics on a clay surface and sand group: performing plyometrics on a dry surface of 20 cm deep sand) or a control group (CG, habitual physical education classes) within their corresponding age groups. Children were tested for sprint, jumping and change of direction speed performances before and after 4 weeks of plyometric training. Both experimental groups induced more significant improvements in all assessed variables than CG (p < 0.0001; effect size > 0.80), whereas both surfaces induced similar improvements (p > 0.05). Older boys achieved better performances than their younger counterparts (p < 0.05) and older girls (p < 0.0001), respectively. This finding showed that age and sex could affect explosive and high-intensity performances during childhood after a short-term plyometric training. In contrast, the training-induced fitness changes were not influenced by the type of surface.

Correlates of the Physical Activity Decline during Childhood

PURPOSE

This study aimed to describe longitudinal trends in children's moderate-to-vigorous physical activity (MVPA) and to investigate associations with individual, familial, and school characteristics.

METHODS

A sample of 341 Portuguese children age 5-10 yr (173 girls) from six age cohorts was followed over 3 yr using a mixed-longitudinal design. Physical activity, body mass index (BMI), gross motor coordination, and musculoskeletal fitness were assessed annually. Information on socioeconomic status and school characteristics was collected and analyzed with mixed models.

RESULTS

MVPA shows a similar declining trend in both sexes, but on average, boys exceeded the World Health Organization recommendations of 60 min·d -1 . The best model showed that boys spend, on average, more time in MVPA than girls. Children with lower BMI are less prone to the decline in MVPA, whereas higher levels of musculoskeletal fitness were associated with lower declines in MVPA. Of all school characteristics, only playground dimension was related to MVPA decreasing trajectories.

CONCLUSIONS

MVPA systematically declines from 5 to 10 yr of age in both boys and girls, but boys remained more active than girls across the age range. The best predictors of MVPA decline are sex, BMI, musculoskeletal fitness, and school playground dimension.

Do Primary School Children Benefit from Drop-Jump Training with Different Schedules of Augmented Feedback about the Jump Height?

In children, the training of jumps leads to improved jumping and running performance. Augmented feedback about the jump height is known to facilitate performance improvements in adults. In the present study, the impact of augmented feedback on jumping performance was investigated in 4th grade primary school children executing drop-jump training for 8 weeks (24 sessions, 3 times/week). Ten children (eight males, two females, aged 9.6 ± 0.3 years), received feedback for 8 weeks, and 11 children (nine males, two females, aged 9.5 ± 0.2 years) received feedback only during the last 4 weeks. Drop-jumps training was integrated in physical education classes. Drop-jump and countermovement-jump heights were improved after 24 training sessions (p < 0.01 for both types of jumps in both groups). Ground contact times of drop-jumps were quite long (>200 ms) and not altered by training, and the reactive strength index of drop-jumps was between 0.75 and 1.5 in most children. Augmented feedback did not facilitate jumping performance like in previous studies with adult participants. In contrast, withholding augmented feedback during the first 4 weeks of training was associated with a reduction in jumping performance (p < 0.01 for drop-jumps, p < 0.05 for countermovement-jumps). Finally, improvements did not transfer to functional motor tasks containing jumps. According to the costs and outcomes we do not recommend drop-jump training with augmented feedback about the jump height for 4th grade physical education classes.

Effects of Surface-Type Plyometric Training on Physical Fitness in Schoolchildren of Both Sexes: A Randomized Controlled Intervention

Plyometric training (PT) has been found to be effective for children’s fitness. However, no study has examined the effects of sex on physical fitness adaptations from surface-type PT in children. This study compared the effects of short-term surface-type PT (firm vs. sand) on the physical fitness of schoolchildren of both sexes. Sixty girls (age = 10.00 ± 1.15 years) and sixty boys (age = 10.02 ± 1.12 years) participated in a short-term (4 weeks), randomized and parallel PT design with pre-to-post measurements. Children were divided into two experimental groups (firm group: PT performed on a clay surface, 20 boys and 20 girls; sand group: PT performed on a dry surface of 20 cm deep sand, 20 boys and 20 girls) and a control group (CG, 20 boys and 20 girls). Squat jump, standing long jump, 20 m sprint, 5-10-5 shuttle, dynamic balance, and maximal aerobic velocity were measured at baseline and after intervention. Both experimental groups showed greater pre-post changes in all assessed variables than the CG (p < 0.0001). No significant differences in pre-post changes were observed relative to surface type or sex (p > 0.05). These findings suggest that a twice-weekly PT program induced physical fitness improvements, which may have transfer to health status during childhood. Additionally, surface type and sex did not affect the training-induced changes in physical fitness.

Effects of Equine-Assistant Activity on Gross Motor Coordination in Children Aged 8 to 10 Years

Generally, adequate motor coordination (MC) ability is one among the critical factors for the overall development of children. In this paper, we have thoroughly analyzed the effects of equine-assistant activity (EAA) training on MC in children. For this purpose, MC test, specifically for children, was used to the Körperkoordinationstest für Kinder (KTK), and a total of 100 children, particularly those in 8 to 10 age, were equally separated into equine-assistant activity group (EAAG) and control group (CG), respectively. The EAAG group has attended a 14-week EAA training program, while the CG joined in physical education activity once per week. The experimental results have indicated that four indices of KTK test (i.e., backward walk [WB], height jump [HH], jumping sideways [JS] and moving sideways [MS], and motor quotient [MQ] score) showed significant differences ( ^∗ P < 0.05) after a 14-week EAA training. Furthermore, the indices of physical fitness test, standing long jump (SLJ), and sit and reach (SAR) showed significant differences ( ^∗ P < 0.05), but the handgrip (HG) increased slightly without significant difference (P > 0.05) after a 14-week EAA training. In conclusion, there were improvements in MC, lower limb strength, and flexibility by EAAG for those who participated in a 14-week EAA training, and this study has demonstrated the effectiveness of the KTK assessment of MC in children 8 to 10 years.

Fitness Level Differences between Students in Kosovo and Montenegro

Geographical, cultural, and socio-economic factors create a different lifestyle. Accordingly, the aim of this research was to identify the differences in anthropometric and fitness characteristics among adolescents living in Montenegro and Kosovo in order to optimize the physical fitness as a consequence of the proactive behavior. Anthropometric characteristics and fitness level measures were assessed by Eurofit testing battery among 600 Kosovar and 600 Montenegrin students, equally distributed by gender. Differences between countries, gender, and age group (13, 14 and 15 years) were assessed with multivariate and univariate analysis of variance. The results showed that Montenegrin students are taller, heavier, and achieve better results in the sit-ups and 20-m endurance shuttle-run tests. Kosovar students achieve better results in the standing broad jump and 10 × 5 m shuttle-run tests. Males achieve significantly better results in all tests, excluding the sit-and-reach test. Statistically significant differences among age groups were found for all variables, regardless gender and country (except for the flamingo and sit-and reach tests). This study is of importance to physical education teachers and curriculum authors to optimize students’ proactive behavior based on the identified anthropometric and physical fitness differences between the two countries, age groups, and genders.