Quadriceps muscle reaction time in obese children.

This study aimed to determine the influence of obesity, according to body mass index (BMI) and fat mass percentage, on quadriceps muscle reaction times. The study utilized a cross-sectional design. The sample size consisted of 42 schoolchildren (54.5% girls) aged 11 to 12 years old. Participant measurements included weight and height, which were used to categorize individuals based on BMI. Additionally, the electrical bioimpedance technique was employed to categorize participants based on their body fat percentage. A sudden destabilization test of the lower limb was performed to assess the reaction time of the rectus femoris, vastus medialis, and vastus lateralis muscles. The results show that overweight/obese children have a longer muscle reaction time for both the rectus femoris (ß = 18.13; p = 0.048) and the vastus lateralis (ß = 14.51; p = 0.042). Likewise, when the children were classified by percentage of body fat the results showed that overfat/obese children have a longer muscle reaction time for both the rectus femoris (ß = 18.13; p = 0.048) and the vastus lateralis (ß = 14.51; p = 0.042). Our results indicate that BMI and fat mass classification negativity alter the muscle reaction time in children. Overweight/obese or overfat/obese children showed longer reaction times in the rectus femoris and vastus lateralis muscles compared to children with normal weight. Based on these findings, it is suggested that in overweight and obese children, efforts not only focus on reducing body weight but that be complemented with training and/or rehabilitation programs that focus on preserving the normal physiological function of the musculoskeletal system.

Physical activity habits associated with health variables in Chilean male school children / Hábitos de actividad física asociados a variables de salud en escolares chilenos varones

Introduction: Physical inactivity is a factor that con-tributes to increased cardiometabolic risk, such as overweightand obesity in schoolchildren.Aim: To associate physical activity habits with morphologi-cal variables (body mass index [BMI], waist circumference[WC], body fat, and fat-free mass), blood pressure, glycemia,handgrip strength (HGS), and countermovement jump (CMJ)in Chilean male schoolchildren. In addition, to compare phys-ically active (PA) schoolchildren to physically inactive (PI)schoolchildren on morphological variables, blood pressure,glycemia, HGS, and CMJ. Material and methods: A cross-sectional study analyzed160 schoolchildren with a mean age of 7.12 ± 4.5 years dis-tributed into PA schoolchildren (n=75) and PI schoolchildren(n=85). A logistic regression was performed to identify theassociation between physical activity habits with factors ofmorphological variables (BMI, WC, body fat, and fat-freemass), blood pressure, glycemia, HGS, and CMJ. In addition,to compare the differences in physical activity habits (physi-cally active vs. physically inactive), a student’s t-test was per-formed for independent samples. Results: Logistic regression showed that physical activityis protective factor against excess body fat of 46% (OR=0.46; 95%CI= 0.22 to 0.95; p= 0.03), hyperglycemia of 25%(OR= 0.25; 95%CI= 0.12 to 0.51; p< 0.0001), high bloodpressure of 31% (OR= 0.31; 95%CI= 0.15 to 0.67; p=0.002), and HGS dominant hand of 40% (OR= 0.40; 95%CI=0.19 to 0.83; p= 0.014). Conclusion: Physical activity protected against excessbody fat, hyperglycemia, hypertension, and decreased HGSin Chilean male schoolchildren. PA schoolchildren exhibitedlower body fat, reduced risk of hyperglycemia and hyper-tension, and improved HGS and CMJ compared to PI school-children.(AU)

Introducción: La inactividad física es un factor que contribuye al aumento del riesgo cardiometabólico, como el sobrepeso y la obesidad en escolares.Objetivo: Asociar los hábitos de actividad física con variables morfológicas (índice de masa corporal [IMC], circunferencia de cintura [CC], grasa corporal y masa libre de grasa), presión arterial, glucemia, fuerza de prensión manual (FPM) y salto con contramovimiento (CMJ) en escolares hombres chilenos. Además, comparar escolares físicamente activos (FA) con escolares físicamente inactivos (FI) en variables morfológicas, presión arterial, glucemia, FPM y CMJ.Material y métodos: Estudio transversal que analizó 160 escolares con una edad media de 7,12 ± 4,5 años distribuidos en escolares FA (n= 75) y escolares FI (n= 85). Se realizó una regresión logística para identificar la asociación entre los hábitos de actividad física con factores de las variables morfológicas (IMC, CC, grasa corporal y masa libre de grasa), presión arterial, glucemia, FPM y CMJ. Además, para comparar las diferencias en los hábitos de actividad física (físicamente activos vs. físicamente inactivos), se realizó la prueba t de Student para muestras independientes.Resultados: La regresión logística mostró que la actividad física es un factor protector contra el exceso de grasa corporal en un 46% (OR= 0,46; IC95%= 0,22 a 0,95; p= 0,03), hiperglucemia en un 25% (OR= 0,25; IC95%= 0,12 a 0,51; p< 0,0001), hipertensión arterial del 31% (OR= 0,31; IC95%= 0,15 a 0,67; p= 0,002), y FPM en mano dominante del 40% (OR= 0,40; IC95%= 0,19 a 0,83; p= 0,014).Conclusión: La actividad física protegió contra el exceso de grasa corporal, la hiperglucemia, la hipertensión arterial y la disminución de FPM en escolares hombres chilenos. Los escolares FA exhibieron menos grasa corporal, menor riesgo de hiperglucemia e hipertensión, y FPM, además de CMJ mejorados en comparación con los escolares FI.(AU)

Effects of combat sports on cognitive function in older people: a systematic review.

INTRODUCTION: This systematic review aimed to analyze the available body of published peer-reviewed studies on the effects of combat sports compared with active/passive control on cognitive function and electrophysiological markers of brain activity in older people. EVIDENCE ACQUISITION: The studies were searched in Scopus, Web of Science, PubMed, MEDLINE, and PsycINFO databases from deadline to June 2023. The PRISMA, TESTEX, RoB, and GRADE scales assessed the evidence's methodological quality and certainty of evidence. The protocol was registered in PROSPERO (code: CRD42022361695). EVIDENCE SYNTHESIS: After reviewing 3768 studies, seven combat sports interventions (score ≥60% in methodological quality) were selected, composed of 381 older people (63% female), with a mean age of 66 years. In the selected studies, interventions based on judo, karate, and taekwondo were carried out, where it was not possible to verify the benefits of combat sports in cognitive function and electrophysiological markers of brain activity regarding active/passive control groups, although the individual results of the analyzed studies indicate that the practice of combat sports favor selective attention, divided attention, executive function, visual perception, and cognitive processing speed in older people. CONCLUSIONS: The available evidence does not allow a definite recommendation regarding combat sports as an effective cognitive function intervention in older people.

Effects of different plyometric training frequencies on physical performance in youth male volleyball players: a randomized trial.

This study aimed to analyze the effect of plyometric training (PT) at different frequencies on jump performance, running sprint speed, and service speed in youth male volleyball players. The participants were randomly assigned to one PT session per week (Experimental Group 1, EG1, n = 15), two PT sessions per week (Experimental Group 2, EG2, n = 14), and a control group (CG, n = 13). The total weekly jumping ranged between 98 and 196 jumps (equalized between, EG1 and, EG2). The assessments performed were squat jump (SJ), countermovement jump (CMJ), CMJ-arms, drop jump (DJ), 5-m sprint, 10-m sprint, and service speed. The intragroup comparisons showed that, EG1 significantly (p < 0.001) improved SJ (Δ = 12.74%; d = 1.30), CMJ (Δ = 11.94%; d = 1.71), CMJ-arms (Δ = 12.02%; d = 1.47), DJ (Δ = 10.93%; d = 1.30), 5-m sprint (Δ = -4.61%; d = 0.29), 10-m sprint (Δ = -3.95%; d = 0.40) and service speed (Δ = 8.17%; d = 1.53). Similarly, EG2 significantly (p˂ 0.001) improved SJ (Δ = 11.52%; d = 1.25), CMJ (Δ = 11.29%; d = 1.38), CMJ-arms (Δ = 11.42%; d = 1.26), DJ (Δ = 13.90%; d = 2.17), 5-m sprint (Δ = -3.85%; d = 0.25), 10-m sprint (Δ = -2.73%; d = 0.25) and service speed (Δ = 6.77%; d = 1.44). The CG significantly (p < 0.05) improved SJ (Δ = 2.68; d = 0.28), CMJ-arms (Δ = 2.30; d = 0.35), 5-m sprint (Δ = -1.27; d = 0.10) and service speed (Δ = 1.42; d = 0.30). Intergroup comparisons revealed significantly greater improvements in all variables (p < 0.001) in, EG1 and, EG2 concerning to CG. However, no significant differences were found between, EG1 and, EG2. A moderate weekly PT volume, distributed in one or two sessions per week, seems equally effective.

Effects of Olympic Combat Sports on Cardiorespiratory Fitness in Non-Athlete Population: A Systematic Review of Randomized Controlled Trials.

This systematic review aimed to assess the available body of published peer-reviewed articles related to the effects of Olympic combat sports (OCS) on cardiorespiratory fitness (CRF) in the non-athlete population. The methodological quality and certainty of evidence were evaluated using PRISMA, TESTEX, RoB, and GRADE scales. The protocol was registered in PROSPERO (code: CRD42023391433). From 4133 records, six randomized controlled trials were included, involving 855 non-athletes (mean age = 27.2 years old). The TESTEX scale reported all studies with a ≥ 60% (moderate-high quality) score. The GRADE scale indicated moderate to low certainty of evidence. It was only possible to perform a meta-analysis on direct methods to maximum oxygen consumption (VO2max). The main results indicated significant differences in favor of OCS compared to active/passive controls in VO2max (SMD = 4.61; 95%CI = 1.46 to 7.76; I2 = 99%; p = 0.004), while the individual results of the studies reported significant improvements in favor of the OCS on the indirect methods of the CRF. OCS improved CRF in a healthy non-athlete population of different ages, specifically showing a significant improvement in VO2max with direct tests, such as cardiopulmonary tests. However, moderate to low certainty of evidence is reported, so no definitive recommendations can be established.

Effectiveness of elastic band training and group-based dance on physical-functional performance in older women with sarcopenia: a pilot study.

BACKGROUND: Sarcopenia is a syndrome associated with aging that causes progressive loss of skeletal muscle mass and muscle function. In this pilot study, we compared the effectiveness of elastic band training regarding group-based dance on fat mass, fat-free mass, handgrip strength (HGS; dominant and non-dominant hand), leg strength, timed up-and-go (TUG) and walking speed in older women with sarcopenia. METHODS: This is a randomized controlled trial, single-blind, repeated measures of parallel groups (elastic band group: EBG, n = 21; group-based dance: GBD, n = 19), and a quantitative methodology. Three 60-minute sessions per week for 12 weeks were dedicated to the interventions with pre- and post-assessments. A two-factor mixed analysis of variance (ANOVA) model with repeated measures was performed to measure the group×time effect. RESULTS: A significant interaction revealed for fat-free mass (F1,16= 18.91; p < 0.001; EBG + 10.9% vs. GBD - 1.97%), HGS dominant hand (F1,16= 7.44; p = 0.014; EBG + 10.9% vs. GBD + 0.59%), HGS non-dominant hand (F1,16= 6.41; p = 0.022; EBG + 10.21% vs. GBD + 3.80%), leg strength (F1,16= 17.98; p < 0.001; EBG + 9.1% vs. GBD + 3.83%), TUG (F1,16= 7.52; p = 0.014; EBG - 14.7% vs. GBD - 1.0%) and walking speed (F1,16 = 6.40; p = 0.019; EBG - 7.6% vs. GBD - 4.35%) in favor of EBG. CONCLUSION: Elastic band training produces significantly greater responses on physical-functional performance regarding group-based dance in older women with sarcopenia. On the other hand, the EBG revealed a significant improvement in fat-free mass and upper and lower limb muscle strength, as well as a significant decrease time in TUG, and walking speed. Elastic band exercise is a safe, easy, affordable, and effective physical activity strategy, according to the findings.

Impact of adapted taekwondo vs. multicomponent training on health status in independent older women: a randomized controlled trial.

This study, called the TKD and Aging Project, aimed to analyze and compare the effects of an adapted taekwondo program concerning multicomponent training on blood pressure, morphological variables, food consumption frequency, health-related quality of life (HRQoL), physical fitness, handgrip strength, and postural balance in independent older women. A randomized controlled trial study was conducted with parallel groups for 8 weeks (24 sessions of 60 min each), employing a double-blind design and incorporating repeated measures. Twenty-eight older women initially participated in the intervention. Three participants were excluded because they did not participate in the re-assessments. Thus, 14 older women from the adapted taekwondo group (TKD; age: 62.86 ± 2.38 years) and 11 from the multicomponent training group (MCT; age: 63.18 ± 1.94 years) participated in the final analysis. A two-factor mixed analysis of variance (ANOVA) model with repeated measures was performed to measure the time × group effect. The TKD showed significant improvements in the mental health (p = 0.024; ES = 0.91) and general health (p < 0.001; ES = 0.75) dimensions of the HRQoL, as well as in the chair stand (p = 0.001; ES = 1.18), arm curl (p < 0.001; ES = 2.10), 2-min step (p < 0.001; ES = 1.73), and chair sit-and-reach (p = 0.001; ES = 0.91) tests. Additionally, it showed a significant reduction in postural balance for the eyes-closed condition in the center of the pressure area (p = 0.021; ES = 0.89), mean velocity (p = 0.004; ES = 0.79), and mediolateral velocity (p < 0.001; ES = 1.26). However, the MCT showed significant increases in the general health (p = 0.013; ES = 0.95) dimension of the HRQoL and a significant reduction (p = 0.039; ES = 0.28) in the mediolateral velocity of postural balance for the eyes-closed condition. Multiple comparisons showed that the TKD scored significantly higher in the chair stand (p = 0.017; ES = 1.79), arm curl (p = 0.003; ES = 1.77), and 2-min step (p = 0.018; ES = 0.91) tests than the MCT. Compared to multicomponent training, taekwondo improves postural balance and provides better benefits in terms of physical fitness and HRQoL for older women. Therefore, it is possible to recommend it as a safe physical activity strategy, as long as it is well-dosed, since it showed high adherence to intervention in older women.

Association between Physical Activity Habits with Cardiometabolic Variables, Body Composition, and Physical Performance in Chilean Older Women.

This study aimed to associate physical activity habits with cardiometabolic variables (blood pressure, fasting glucose, HDL cholesterol, and triglycerides), body composition (body fat percentage and fat-free mass), and physical performance (handgrip strength (HGS), timed up-and-go (TUG), and walking speed) in Chilean older women. An analytical cross-sectional study analyzed 179 older women with a mean age of 75.4 years distributed into physically inactive (PI) older women (n = 74) and physically active (PA) older women (n = 105). A logistic regression showed that PI older women presented an increased risk of hyperglycemia (OR = 4.70; p = 0.000), high blood pressure (OR = 3.83; p = 0.000), low HDL cholesterol levels (OR = 2.13; p = 0.03), hypertriglyceridemia (OR = 2.54; p = 0.01), excess body fat percentage (OR = 4.33; p = 0.000), low fat-free mass (OR = 2.22; p = 0.02), low HGS in their dominant hand (OR = 3.37; p = 0.001) and non-dominant hand (OR = 3.60; p = 0.0001), and poor performance in TUG (OR = 5.60; p = 0.000) and walking speed (OR = 5.52; p = 0.000). In conclusion, physical inactivity was associated with increased cardiometabolic risk, excess body fat percentage, lower fat-free mass, and poorer physical performance in Chilean older women. At the same time, PA older women showed a lower cardiometabolic risk, better body composition, and better physical performance than PI older women.

Factors Associated with Anxiety, Depression, and Stress Levels in High School Students.

This study aims to investigate the relationship between anxiety, depression, and stress levels with physical activity level and academic performance in high school students; secondly, this study aims to relate and compare anxiety, depression, and stress levels with physical activity level and academic performance. This is a quantitative, descriptive, and comparative cross-sectional study, which evaluated 443 high school students (48% female; 15.13 ± 1.59 years) belonging to the Maule region, Chile. The Depression, Anxiety, and Stress Questionnaire (DASS-21) and the International Physical Activity Questionnaire (IPAQ) were applied. Academic performance was consulted on language, mathematics, and overall grade point average. The results indicate that vigorous physical activity (OR = 0.504; p = 0.017) and high academic performance in mathematics (OR = 0.597; p = 0.027) are associated with a reduced risk of depression. In turn, there is a significant inverse correlation between physical activity with anxiety (r = -0.224; p = 0.000), depression (r = -0.224; p = 0.000) and stress (r = -0.108; p = 0.032), while the performance of mathematics is inversely correlated with depression (r = -0.176; p = 0.000). On the other hand, significant differences (p < 0.05) between anxiety, depression, stress levels, and grade point average were found, with females exhibiting higher scores than males. In conclusion, greater vigorous physical activity and scoring above average in mathematics performance are protective factors against depression.

An investigation into the associations between psychological skills, anaerobic fitness, and aerobic fitness in elite Iranian taekwondo athletes.

This study investigated the relationship between psychological skills and fitness levels among elite taekwondo athletes. A total of ten Iranian male elite taekwondo athletes (mean age of 20.6±2 years, BMI 18.78±0.62 kg/m2, and fat percentage of 8.87±1.46%) participated in the study. The Sports Emotional Intelligence Questionnaire, Sports Success Scale, Sport Mental Toughness Questionnaire, and Mindfulness Inventory for Sport were used to assess psychological factors. The Wingate test was used to determine anaerobic power, and the Bruce test to determine aerobic fitness. Descriptive statistics and Spearman rank correlation coefficients were utilised to examine any relationships between subscales. Statistically significant correlations were recorded between the evaluation of feelings (EI scale) and VO2peak (ml/kg/min) (r = -0.70, p = 0.0235) and between social skills (EI scale) and relative peak power (W/kg) (r = 0.84, p = 0.0026). Also, between optimism (EI scale) and VO2peak (ml/kg/min) (r = -0.70, p = 0.0252) and between optimism (EI scale) and HR-MAX (r = -0.75, p = 0.0123); and, finally, between control (mental toughness scale) and relative peak power (W/kg) (r = 0.67, p = 0.0360). These findings demonstrate relationships between psychological factors and the advantages of good anaerobic and aerobic capabilities. Finally, the study also demonstrated that elite taekwondo athletes have high mental performance abilities that are interrelated with anaerobic and aerobic performance.

Time-motion analysis of taekwondo matches in the Tokyo 2020 Olympic Games.

BACKGROUND: The aim of the present study was to determine the time-motion structure of high-level taekwondo matches during the Tokyo 2020 Olympic Games in relation to sex, match outcome, weight category and match round. METHODS: Overall, 7007 actions were recorded during the analysis of 134 performances (67 rounds of 24 matches: four rounds of 16, eight quarterfinals, eight semifinals and four finals) in male and female flyweight (≤58 kg and ≤49 kg, respectively), and heavyweight categories (≥80 kg and ≥67 kg, respectively). The attack time (AT), number of AT (AN), skipping time (ST) and pause time (PT) were registered. RESULTS: The AT/ST ratio was ~1:1.5. Male athletes performed significantly longer (P<0.001) sum PT than female athletes. Flyweight athletes differed significantly from their heavyweight counterparts by having longer (P<0.001) average and sum AT, greater (P<0.001) AN, higher (P<0.001) AT/ST ratio, shorter (P<0.001) average and sum ST, and lower (P<0.01) (AT+ST)/PT ratio. Rounds 2 and 3 had average PT significantly longer (P<0.01) than round 1. Round 3 had sum PT longer (P<0.001) and (AT+ST)/PT ratio lower than in round 1. CONCLUSIONS: The rule changes and the implementation of the electronic score recording system had a major impact on the time-motion structure of combat by generating a considerably higher AT/ST ratio than in the past. The comparisons indicated that the structure of the combat is modulated by weight category and phase of the combat. In practice, coaches could develop sport-specific high-intensity interval training using the time-motion indexes of the present study as guidelines.

Comparación del consumo alimentario y calidad de vida relacionada con la salud entre baloncestistas de distinto nivel competitivo / Comparison of food consumption and health-related quality of life amongbasketball players of different competitive levels

Introducción: Los hábitos alimentarios y la salud mental son aspectos fundamentales para optimizar la preparación y el rendimiento deportivo de los baloncestistas.Objetivo: Comparar la frecuencia en el consumo de alimentos y la calidad de vida relacionada con la salud (CVRS)entre baloncestistas de distinto nivel competitivo (profesional,universitario y amateur). Material y métodos: Estudio transversal que evaluó 122baloncestistas masculinos (edad media de 30,60 ± 10,79años), distribuidos en jugadores de baloncesto profesional(JBP; n=25), universitario (JBU; n=26) y amateur (JBA;n=71). Las variables de estudio se evaluaron a través de encuestas en línea referentes a la frecuencia en el consumo de alimentos y CVRS (SF-36). Resultados: Los JBP ostentan un consumo significativamente mayor de cena (F= 5,007; p= 0,020) comparados conlos JBU, y de frutas (F= 5,857; p= 0,012), verduras (F= 3,756; p= 0,020) y cena (F= 5,007; p= 0,011) respecto a losJBA. Mientras que los JBU presentan un consumo significativamente mayor de frutas (F= 5,857; p= 0,035) que los JBA.Además, los JBU presentaron un consumo significativamente mayor de bebidas azucaradas (F= 9,293; p= 0,004) respecto a los JBP y JBA. La CVRS no presentó diferencias significativas entre los grupos. Conclusión: Los JBP presentan mayor frecuencia en el consumo de alimentos saludables al compararlos con JBU yJBA. Además, los JBU reportan mayor frecuencia en el consumo de bebidas azucaradas respecto a JBP y JBA. Mientras que, la CVRS es positiva independiente al nivel competitivo delos baloncestistas.(AU)

Introduction: Eating habits and mental health are fundamental aspects to optimize the preparation and sports performance of basketball players.Aim: To compare the frequency of food consumption andhealth-related quality of life (HRQoL) among basketball players of different competitive levels (professional, university,and amateur).Material and methods: Cross-sectional study that evaluated 122 male basketball players (mean age of 30.60 ± 10.79years), divided into professional (JBP; n=25), university (JBU;n=26) and amateur (JBA; n=71). The study variables wereevaluated through online surveys regarding the frequency offood consumption and HRQoL (SF-36). Results: The JBP show a significantly higher consumption of dinner (F= 5,007; p= 0,020) compared to the JBU,and of fruits (F= 5,857; p= 0,012), vegetables (F= 3,756;p= 0,020) and dinner (F= 5,007; p= 0,011) compared tothe JBA. While the JBU present a significantly higher con-sumption of fruits (F= 5,857; p= 0,035) than the JBA. In addition, the JBU had a significantly higher consumption ofsugary drinks (F= 9,293; p= 0,004) compared to the JBPand JBA. The HRQoL did not present significant differencesbetween the groups.Conclusion: The JBP have a higher frequency in the consumption of healthy foods when compared to JBU and JBA. Inaddition, the JBU report a higher frequency in the consumption of sugary drinks compared to the JBP and JBA. While, theHRQoL is positive regardless of the competitive level of thebasketball players.

Corrigendum: Warm-up stretching exercises and physical performance of youth soccer players.

[This corrects the article DOI: 10.3389/fphys.2023.1127669.].

Warm-up stretching exercises and physical performance of youth soccer players.

This study aims to compare the effects of standard warm-up versus warm-up using stretching exercises on the physical performance of male youth soccer players. Eighty-five male soccer players (age: 10.3 ± 4.3 years; body mass index: 19.8 ± 4.3 kg/m2) were assessed for countermovement jump height (CMJ, cm), 10 m, 20 m and 30 m running sprint speed (s) and ball kicking speed (km/h) for the dominant and non-dominant leg under five (randomized) warm-up conditions. Using 72 h of recovery between conditions, the participants completed a control condition (CC) and four experimental conditions, including static stretching (SSC), dynamic stretching (DSC), ballistic stretching (BSC), and proprioceptive neuromuscular facilitation (PNFC) exercises. All warm-up conditions had a duration of 10 minutes. The main results indicate that no significant differences (p > 0.05) were found between warm-up conditions compared to CC in CMJ (CC = 28.1 ± 4.9; SSC = 28.4 ± 4.9; DSC = 30.9 ± 4.8; BSC = 30.9 ± 5.2; PNFC = 28.4 ± 5.0), 10 m sprint (CC = 2.42 ± 0.4; SSC = 2.50 ± 0.4; DSC = 2.30 ± 0.3; BSC = 2.27 ± 0.3; PNFC = 2.53 ± 0.4), 20 m sprint (CC = 5.42 ± 0.9; SSC = 5.59 ± 0.9; DSC = 5.37 ± 0.9; BSC = 5.40 ± 0.9; PNFC = 5.44 ± 0.9), 30 m sprint (CC = 8.05 ± 1.3; SSC = 8.27 ± 1.3; DSC = 8.01 ± 1.3; BSC = 8.00 ± 1.3; PNFC = 8.12 ± 1.3), ball kicking speed for dominant (CC = 56.2 ± 4.9; SSC = 55.3 ± 5.2; DSC = 56.9 ± 5.8; BSC = 57.3 ± 5.8; PNFC = 55.7 ± 5.2) and non-dominant leg (CC = 52.8 ± 3.4; SSC = 51.8 ± 4.6; DSC = 53.5 ± 5.4; BSC = 53.6 ± 4.9; PNFC = 52.5 ± 4.0). In conclusion, compared to standard warm-up, stretching-based warm-up exerts no effect on male youth soccer players jump height, sprint speed and ball kicking speed.

Validity and Reliability of Short-Term Heart Rate Variability Parameters in Older People in Response to Physical Exercise.

BACKGROUND: Currently, and to the best of our knowledge, there is no standardized protocol to measure the effect of low- to moderate-intensity physical exercise on autonomic modulation focused in older people. AIM: Validate a test-retest short-term exercise protocol for measuring the autonomic response through HRV in older people. METHODS: A test-retest study design was used. The participants were selected through intentional non-probabilistic sampling. A total of 105 older people (male: 21.9%; female: 78.1%) were recruited from a local community. The assessment protocol evaluated HRV before and immediately after the 2-min step test. It was performed twice on the same day, considering a time of three chronological hours between the two measurements. RESULTS: The posterior distribution of estimated responses in the Bayesian framework suggests moderate to strong evidence favoring a null effect between measurements. In addition, there was moderate to robust agreement between heart rate variability (HRV) indices and assessments, except for low frequency and very low frequency, which showed weak agreement. CONCLUSIONS: Our results provide moderate to strong evidence for using HRV to measure cardiac autonomic response to moderate exercise, suggesting that it is sufficiently reliable to show similar results to those shown in this test-retest protocol.

A Systematic Review with Meta-Analysis on the Effects of Plyometric-Jump Training on the Physical Fitness of Combat Sport Athletes.

We aimed to assess the athletic performance changes in combat sport athletes (CoSAs) after plyometric-jump training (PJT), compared to control conditions, through a systematic review with meta-analysis. Following PRISMA guidelines, three electronic databases were searched for includable articles, according to a PICOS approach. Using a random-effects model, Hedges' g effects sizes (ES) were calculated. Heterogeneity was assessed using the I2 statistic, with values of <25%, 25-75%, and >75% representing low, moderate, and high levels of heterogeneity, respectively. Statistical significance was set at p ≤ 0.05. The certainty of evidence was assessed using the GRADE approach. Twelve eligible articles were identified for systematic review, seven of high quality and five of moderate quality, according to the PEDro scale. The studies recruited taekwondo, silat, wrestling, judo, fencing, and karate athletes (292 total participants), including specific-active and active controls. Most participants had a mean age of <18 years and were males (n = 225). Compared to the control, PJT programmes, involving 4-12 weeks and 2-3 sessions per week, induced small to moderate improvements (ES = 0.47 to 1.04) in athletes' maximal strength (e.g., 1RM squat), vertical jump height, change-of-direction speed, and specific performance (e.g., fencing movement velocity), although without meaningful effects on body mass, fat mass, and muscle mass (ES = 0.02 to -0.06). Most (7 of 8) outcomes attained low heterogeneity. The outcome-level GRADE analysis indicated a certainty of evidence from low to moderate. In conclusion, PJT, when compared to control conditions, may improve CoSA athletic performance.

Effects of Strength Training on Physical Fitness of Olympic Combat Sports Athletes: A Systematic Review.

This review aimed to identify the effects of strength training programs on the physical fitness of Olympic combat sports (OCS) athletes. The systematic review included peer-reviewed articles that incorporated interventions that included pre- and post-intervention physical fitness assessment. The search was performed in the SCOPUS, PubMed, and Web of Science databases between April and September 2022. PRISMA and the TESTEX checklist were used to select and assess the methodological quality of the studies. Twenty studies with 504 participants (428 males and 76 females) were included. Significant improvements were found in athletes' maximal dynamic and isometric strength, muscle power, flexibility, and balance. In addition, improvements in favor of the training groups in specific actions of judo, karate, fencing, and boxing were observed. In conclusion, interventions aimed at the development of muscle strength in OCS, specifically in judo, boxing, karate, wrestling, and fencing, proved to be beneficial at a physical fitness level, resulting in significant increases in favor of the training groups with OCS, which could be used by trainers and coaches to improve the physical performance of athletes.

Relation between VT1, VT2, and VO2max with the Special Wrestling Fitness Test in Youth Wrestlers: A Short Report.

This study investigated the relationship between peak oxygen uptake and ventilatory threshold 1 (VT1) and 2 (VT2) with the Special Wrestling Fitness Test variables. Thirteen wrestlers (male: six; female: seven) of Olympic freestyle wrestling were assessed. The Pearson's correlation coefficient (p < 0.05) was used to establish the relationship between variables. A positive correlation was found between VT1 with throws in set B (r = 0.77; p = 0.002; 95%CI = 0.37-0.93), total throws (r = 0.73; p = 0.004; 95%CI = 0.30-0.91), heart rate recovery (r = 0.58; p = 0.036; 95%CI = 0.05-0.86), and test index (r = -0.60; p = 0.031; 95%CI = -0.86-0.07); between VT2 and throws in set B (r = 0.57; p = 0.043; 95%CI = 0.01-0.86); and between peak oxygen uptake with throws in set B (r = 0.77; p = 0.002; 95%CI = 0.39-0.93), throws in set C (r = 0.64; p = 0.02; 95%CI = 0.12-0.89), and total throws (r = 0.72; p = 0.006; 95%CI = 0.28-0.91). In conclusion, the peak oxygen uptake and ventilatory thresholds correlated with specific Special Wrestling Fitness Test variables.

Anthropometric Profile and Physical Activity Level as Predictors of Postural Balance in Overweight and Obese Children.

Overweightness and obesity can negatively influence many activities, including postural balance and locomotion, increasing predisposition to injury and risk of falls due to limitations on the biomechanics of daily living. The present study aimed to determine the influence of the anthropometric profile and physical activity level (PAL) on the postural balance of overweight and obese children. The sample included 387 schoolchildren (216 boys and 171 girls). The variables of the anthropometric profile studied were body mass, biped height, BMI, waist circumference, waist-to-hip ratio (WHR), summation of folds, body composition, and somatotype. PAL was measured using the PAQ-C questionnaire. Static and dynamic postural balance were measured through an open-eye (OE) and closed-eye (CE) posturographic test and the SEBTm, respectively. For static balance, the significant models were for mediolateral velocity (R2 = 0.42 in OA; R2 = 0.24 in OC), anteroposterior velocity (R2 = 0.21 in OA; R2 = 0.27 in OC), and mean velocity (R2 = 0.27 in OA; R2 = 0.46 in OC), where the predictors of low performance were younger age, male sex, overweight/obese nutritional status, greater thickness of skin folds, less tendency to mesomorphy, and greater fat mass. On the other hand, for dynamic postural balance, the significant models were observed in the previous direction (R2 = 0.39), posteromedial (R2 = 0.57), and posterolateral (R2 = 0.56), where the variables that predict a low performance were low PAL, overweight/obese nutritional status, and high WHR. Overweight and obese children presented a deficit in static and dynamic postural balance, enhanced by variables such as gender, age, PAL, and anthropometric characteristics related to adiposity.

Factors Associated with Poor Health-Related Quality of Life in Physically Active Older People.

This study aimed to associate morphological variables and physical fitness with health-related quality of life (HRQoL) in physically active older people. A cross-sectional study was carried out that evaluated 470 older people (89.57% female) with a mean age of 70.13 ± 6.57 years, residing in two regions of Chile. Morphological variables (body weight, bipedal height, waist circumference, body mass index, and waist to height ratio), physical fitness through the Senior Fitness Test protocol, and HRQoL using the SF-36 questionnaire were obtained. Logistic regression analysis was used to identify risk factors between morphological variables and physical fitness associated with HRQoL. The main results indicated that overweight (OR = 1.52; p = 0.034), a waist circumference with risk (OR = 1.56; p = 0.021), poor performance in the back scratch tests (OR = 1.02; p = 0.008) and timed up-and-go (OR = 1.19; p = 0.040) increased the probability of having a low general HRQoL. Also, the low performance of chair stand and arm curl tests was associated with poor physical and social dimensions of HRQoL (p < 0.05). In conclusion, a low HRQoL in physically active older people is associated with both morphological and physical fitness factors.