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1.
BMC Public Health ; 24(1): 799, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481212

RESUMO

In the present study, we investigated the relationship between personality and motivation for physical activity while introducing perceived parental support and social physical anxiety in adolescent girls (N = 318, Mage: 16.19 ± 0.51 years). The present study was a retrospective correlational study that was conducted to analyze of a path model. Dark triad traits: Machiavellianism, narcissism, and psychopathy, student's motivation for physical activity, social physique anxiety, and participants' perceptions of parents' behaviors were measured. The findings indicated that psychopathy and Machiavellianism were directly and indirectly associated with motivation for physical activity, but Narcissism could only directly predict the motivation for physical activity. Also, need-thwarting (the most), need-supportive and social physical anxiety could predict motivation for physical activity. This model of the result suggests that among adolescent girls, dark triad personality could, directly and indirectly, predict motivation with need-supportive and need-thwarting and also social physical anxiety. It seems that the sense of importance and more attention to oneself in adolescent girls, which exists in the narcissistic personality, can directly lead to more motivation for physical activity. Also, the duplicitous ways of Machiavellian people in pursuing their motives were confirmed in this research.


Assuntos
Motivação , Personalidade , Feminino , Humanos , Adolescente , Estudos Retrospectivos , Transtorno da Personalidade Antissocial , Maquiavelismo , Exercício Físico , Pais , Ansiedade
2.
Exp Physiol ; 108(1): 90-102, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36394370

RESUMO

NEW FINDINGS: What is the central question of the study? Are the changes in force potentials (at the muscle level) related with metabolic changes at speeds above and below the walk-to-run transition? What is the main finding and its importance? The force-length and force-velocity potentials of gastrocnemius medialis during human walking decrease as a function of speed; this decrease is associated with an increase in cumulative EMG activity and in the energy cost of locomotion. Switching from fast walking to running is associated to an increase in the force potentials, supporting the idea that the 'metabolic trigger' that determines the transition from walking to running is ultimately driven by a reduction of the muscle's contractile capacity. ABSTRACT: The aim of this study was to investigate the interplay between the force-length (F-L) and force-velocity (F-V) potentials of gastrocnemius medialis (GM) muscle fascicles, the cumulative muscle activity per distance travelled (CMAPD) of the lower limb muscles (GM, vastus lateralis, biceps femori, tibialis anterior) and net energy cost (Cnet ) during walking and running at speeds above and below the walk-to-run transition speed (walking: 2-8 km h-1 ; running: 6-10 km h-1 ). A strong association was observed between Cnet and CMAPD: both changed significantly with walking speed but were unaffected by speed in running. The F-L and F-V potentials decreased with speed in both gaits and, at 6-8 km h-1 , were significantly larger in running. At low to moderate walking speeds (2-6 km h-1 ), the changes in GM force potentials were not associated with substantial changes in CMAPD (and Cnet ), whereas at walking speeds of 7-8 km h-1 , even small changes in force potentials were associated with steep increases in CMAPD (and Cnet ). These data suggest that: (i) the walk to run transition could be explained by an abrupt increase in Cnet driven by an upregulation of the EMG activity (e.g., in CMAPD) at sustained walking speeds (>7 km h-1 ) and (ii) the reduction in the muscle's ability to produce force (e.g., in the F-L and F-V potentials) contributes to the increase in CMAPD (and Cnet ). Switching to running allows regaining of high force potentials, thus limiting the increase in CMAPD (and Cnet ) that would otherwise occur to sustain the increase in locomotion speed.


Assuntos
Corrida , Caminhada , Humanos , Eletromiografia , Fenômenos Biomecânicos , Caminhada/fisiologia , Músculo Esquelético/fisiologia , Corrida/fisiologia
3.
Res Sports Med ; 31(1): 13-20, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-33988477

RESUMO

The aim of this study was to assess the metabolic cost (Cr) with marathon shoes (Adidas Adizero 3 [AA]) vs. track spikes (Nike Zoom Matumbo 3 [NZM]) on track. For this, five experienced runners were randomly assessed (NZM/AA) on a running track at 73% and 85% of best performance speed on 1500-m race. At first, speed (4.39 ± 0.53 m·s-1), Crs with AA and NZM resulted 3.63 ± 0.29 and 3.64 ± 0.43 J·kg-1·m-1 (+0.3% with NZM, effect size [ES] small and p = 0.951), respectively. Besides, at second speed (5.20 ± 0.18 m·s-1), Crs were 4.09 ± 0.28 and 4.07 ± 0.22 J·kg-1·m-1 (-0.5% with NZM, ES small and p = 0.919) with AA and NZM, respectively. It resulted in an increased Cr (+12.2%) between s1 and s2 with both shoe conditions (ES large and p = 0.009 and 0.011 with AA and NZM, respectively). There is a pattern yet to be confirmed for track spikes to become more beneficial at higher speeds (when duty factor becomes lower and therefore grip on track is crucial).


Assuntos
Corrida de Maratona , Corrida , Humanos , Sapatos , Projetos Piloto , Fenômenos Biomecânicos
4.
Res Sports Med ; 31(4): 319-330, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34383574

RESUMO

This study compared the sensitivity of peak running speed (PRS) measured during a submaximal run test (SRT) with a countermovement jump (CMJ) test to provide an alternate method of measuring neuromuscular fatigue (NMF). The study involved 20 semi-professional academy soccer players who performed a SRT and CMJ test, 24-hours pre-match, 24-, 48-, 72- and 96-hours post-match. Moderate decreases (effect-size (ES) ± 90% confidence intervals) were observed 24-hours post-match for CMJH; ES -0.70 ± 0.19, CMJPV; ES -0.92 ± 0.27 and PRS; ES -0.58 ± 0.11 with small decreases in CMJH; ES -0.36 ± 0.13 and PRS; ES -0.27 ± 0.23 still evident 48-hours post-match before returning to baseline 72-hours post-match. The results confirm PRS as an inexpensive alternate method of measuring NMF which, allows instantaneous real-time feedback on NMF. This can allow changes to be made immediately on-field within the post-match recovery phase without the need for further analysis or equipment.


Assuntos
Desempenho Atlético , Corrida , Futebol , Humanos , Esportes de Equipe , Fadiga Muscular , Atletas
5.
Scand J Med Sci Sports ; 32(5): 844-855, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35138687

RESUMO

This study combines metabolic and kinematic measurements at the whole-body level, with EMG and ultrasound measurements to investigate the influence of muscle-tendon mechanical behavior on the energy cost (Cnet ) of walking (from 2 to 8 km·h-1 ). Belly gearing (Gb = Δmuscle-belly length/Δfascicles length) and tendon gearing (Gt = ∆muscle-tendon unit length/∆muscle-belly length) of vastus lateralis (VL) and gastrocnemius medialis (GM) were calculated based on ultrasound data. Pendular energy recovery (%R) was calculated based on kinematic data, whereas the cumulative activity per distance travelled (CMAPD) was calculated for the VL, GM, tibialis anterior, and biceps femoris as the ratio between their EMG activity and walking speed. Finally, total CAMPD (CMAPDTOT ) was calculated as the sum of the CMAPD of all the investigate muscles. Cnet and CMAPDTOT showed a U-shaped behavior with a minimum at 4.2 and 4.1 km·h-1 , respectively; while %R, VL, and GM belly gearing showed an opposite trend, reaching a maximum (60% ± 5%, 1.1 ± 0.1 and 1.5 ± 0.1, respectively), between 4.7 and 5 km·h-1 . Gt was unaffected by speed in GM (3.5 ± 0.1) and decreased as a function of it in VL. A multiple stepwise linear regression indicated that %R has the greatest influence on Cnet, followed by CMAPDTOT and GM belly gearing. The role of Gb on Cnet could be attributed to its role in determining muscle work: when Gb increases, fascicles shortening decreases compared with that of the muscle-belly, thereby reducing the energy cost of contraction.


Assuntos
Músculo Esquelético , Tendões , Fenômenos Biomecânicos , Eletromiografia , Humanos , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Tendões/diagnóstico por imagem , Tendões/fisiologia , Ultrassonografia , Caminhada
6.
J Sports Sci ; 40(11): 1206-1213, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35442850

RESUMO

Movement velocity has been viewed as one of the bilateral deficit (BLD) determinants. This research tested the velocity effect on BLD during a half-squat exercise. The role of muscle excitation in BLD was also assessed. BLD amplitude was assessed in 12 male soccer players while performing a half-squat exercise with incremental load. During the exercise's pushing phase, the average force and velocity were measured in bilateral and unilateral conditions to provide the bilateral index (BI) at each interpolated velocity. The vastus lateralis and medialis excitation was assessed during the exercise by calculating the surface electromyography signal root mean square (sEMGRMS). The BI for sEMGRMS (sEMG BI) was calculated. The theoretical maximum force (F0) and velocity (v0) were also determined. F0 was +43 (28)% in bilateral compared with unilateral conditions (p < 0.001), whereas v0 was similar in both conditions (p = 0.386). The BI magnitude rose with the increase in velocity from -34 (7)% at 50%v0 to -70 (17)% at 90%v0 (p 0.03-<0.001), whereas no sEMG BI occurred (p: 0.07-0.991 in both muscles). The study reported velocity-dependent changes in the BLD amplitude, with the largest BLD amplitudes occurring at the highest velocities. This behaviour could provide useful information for setting specific contraction velocities to exploit/limit the BLD amplitude as a possible training stimulus.


Assuntos
Exercício Físico , Músculo Esquelético , Eletromiografia , Exercício Físico/fisiologia , Humanos , Masculino , Movimento/fisiologia , Músculo Esquelético/fisiologia , Músculo Quadríceps
7.
Int J Sports Med ; 38(14): 1083-1089, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29050041

RESUMO

The aim was to compare lower-limb power, force, and velocity capabilities between squat and leg press movements. Ten healthy sportsmen performed ballistic lower-limb push-offs against 5-to-12 different loads during both the squat and leg press. Individual linear force-velocity and polynomial power-velocity relationships were determined for both movements from push-off mean force and velocity measured continuously with a pressure sensor and linear encoder. Maximal power output, theoretical maximal force and velocity, force-velocity profile and optimal velocity were computed. During the squat, maximal power output (17.7±3.59 vs. 10.9±1.39 W·kg-1), theoretical maximal velocity (1.66±0.29 vs. 0.88±0.18 m·s-1), optimal velocity (0.839±0.144 vs. 0.465±0.107 m·s-1), and force-velocity profile (-27.2±8.5 vs. -64.3±29.5 N·s·m-1·kg-1) values were significantly higher than during the leg press (p=0.000, effect size=1.72-3.23), whereas theoretical maximal force values (43.1±8.6 vs. 51.9±14.0 N·kg-1, p=0.034, effect size=0.75) were significantly lower. The mechanical capabilities of the lower-limb extensors were different in the squat compared with the leg press with higher maximal power due to much higher velocity capabilities (e.g. ability to produce force at high velocities) even if moderately lower maximal force qualities.


Assuntos
Extremidade Inferior/fisiologia , Força Muscular , Músculo Esquelético/fisiologia , Levantamento de Peso/fisiologia , Adulto , Fenômenos Biomecânicos , Estudos Cross-Over , Humanos , Masculino , Adulto Jovem
8.
J Sports Sci ; 34(15): 1466-72, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26643977

RESUMO

Testing is one of the important tasks in any multi-step sport programme. In most ball games, coaches assess motor, physical and technical skills on a regular basis in early stages of talent identification in order to further athletes' development. The purpose of the study was to investigate anthropometric variables and vertical jump heights as a free throw effectiveness predictor in water-polo players of different age groups. Two hundred and thirty-six young (10-18 years) male water-polo players partitioned into three age groups underwent anthropometric variables' measures and squat- and countermovement-jump tests, and performed water-polo free throws. Anthropometric variables, vertical jump heights and throw speed - as a proxy for free throw effectiveness - resulted different over age groups. Particularly, throw speed changed from 9.28 to 13.70 m · s(-1) (+48%) from younger to older players. A multiple-regression model indicated that body height, squat-jump height and throw time together explain 52% of variance of throw speed. In conclusion, tall height, high lower limb power and throwing quickness appeared to be relevant determinants for effective free throws. Such indications can help coaches during talent identification and development processes, even by means of novel training strategies. Further research is needed over different maturity statuses.


Assuntos
Fatores Etários , Antropometria , Aptidão , Destreza Motora/fisiologia , Força Muscular , Esportes/fisiologia , Adolescente , Desempenho Atlético/fisiologia , Criança , Teste de Esforço/métodos , Humanos , Masculino , Exercício Pliométrico , Análise de Regressão
9.
J Sports Sci ; 33(17): 1853-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25751742

RESUMO

This study aimed to apply a validated bioenergetics model of sprint running to recordings obtained from commercial basic high-sensitivity global positioning system receivers to estimate energy expenditure and physical activity variables during soccer refereeing. We studied five Italian fifth division referees during 20 official matches while carrying the receivers. By applying the model to the recorded speed and acceleration data, we calculated energy consumption during activity, mass-normalised total energy consumption, total distance, metabolically equivalent distance and their ratio over the entire match and the two halves. Main results were as follows: (match) energy consumption = 4729 ± 608 kJ, mass normalised total energy consumption = 74 ± 8 kJ · kg(-1), total distance = 13,112 ± 1225 m, metabolically equivalent distance = 13,788 ± 1151 m and metabolically equivalent/total distance = 1.05 ± 0.05. By using a very low-cost device, it is possible to estimate the energy expenditure of soccer refereeing. The provided predicting mass-normalised total energy consumption versus total distance equation can supply information about soccer refereeing energy demand.


Assuntos
Metabolismo Energético/fisiologia , Sistemas de Informação Geográfica/economia , Futebol/fisiologia , Adulto , Custos e Análise de Custo , Humanos , Masculino , Corrida/fisiologia
10.
J Sports Sci ; 33(14): 1454-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25529051

RESUMO

The free throw (FT) is a fundamental basketball skill used frequently during a match. Most of actual play occurs at about 85% of maximum heart rate (HR). Metabolic intensity, through fatigue, may influence a technically skilled move as the FT is. Twenty-eight under 17 basketball players were studied while shooting FTs on a regular indoor basketball court. We investigated FT accuracy in young male basketball players shooting at three different HRs: at rest, at 50% and at 80% of maximum experimentally obtained HR value. We found no significant FT percentage difference between rest and 50% of the maximum HR (FT percentage about 80%; P > 0.05). Differently, at 80% of the maximum HR the FT percentage decreased significantly by more than 20% (P < 0.001) down to about 60%. No preliminary warm-up is needed before entering game for the FT accuracy. Furthermore, we speculate that time-consuming, cooling-off routines usually performed by shooters before each FT may be functional to improve its accuracy.


Assuntos
Desempenho Atlético/fisiologia , Basquetebol/fisiologia , Metabolismo Energético , Destreza Motora/fisiologia , Adolescente , Fadiga/fisiopatologia , Frequência Cardíaca , Humanos , Masculino , Exercício de Aquecimento/fisiologia
11.
Front Mol Biosci ; 11: 1389325, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38894711

RESUMO

Endometrial cancer, which is the most common gynaecological cancer in women after breast, colorectal and lung cancer, can be diagnosed at an early stage. The first aim of this study is to classify age, tumor grade, myometrial invasion and tumor size, which play an important role in the diagnosis and prognosis of endometrial cancer, with machine learning methods combined with explainable artificial intelligence. 20 endometrial cancer patients proteomic data obtained from tumor biopsies taken from different regions of EC tissue were used. The data obtained were then classified according to age, tumor size, tumor grade and myometrial invasion. Then, by using three different machine learning methods, explainable artificial intelligence was applied to the model that best classifies these groups and possible protein biomarkers that can be used in endometrial prognosis were evaluated. The optimal model for age classification was XGBoost with AUC (98.8%), for tumor grade classification was XGBoost with AUC (98.6%), for myometrial invasion classification was LightGBM with AUC (95.1%), and finally for tumor size classification was XGBoost with AUC (94.8%). By combining the optimal models and the SHAP approach, possible protein biomarkers and their expressions were obtained for classification. Finally, EWRS1 protein was found to be common in three groups (age, myometrial invasion, tumor size). This article's findings indicate that models have been developed that can accurately classify factors including age, tumor grade, and myometrial invasion all of which are critical for determining the prognosis of endometrial cancer as well as potential protein biomarkers associated with these factors. Furthermore, we were able to provide an analysis of how the quantities of the proteins suggested as biomarkers varied throughout the classes by combining the SHAP values with these ideal models.

12.
J Funct Morphol Kinesiol ; 9(2)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38921631

RESUMO

Early childhood is a critical period for physical and motor development with implications for long-term health. This systematic review examined the relationship between anthropometric characteristics and measures of physical fitness and motor skills in preschool-aged children (typically 2-6 years). The search strategy was applied in four databases (PubMed, ProQuest Central, Scopus, and Web of Science) to find articles published before 11 April 2024. The results consistently demonstrated significant associations between anthropometric variables (height, weight, body mass index [BMI], body composition) and physical performance measures. Notably, height and mass were often better predictors of fitness status than BMI alone. Indicators of undernutrition (stunting, wasting) were negatively associated with motor development, emphasizing the importance of adequate nutrition. While some studies reported impaired fitness and motor skills among overweight/obese preschoolers compared to normal-weight peers, others found no differences based on weight status. Relationships between physical activity levels, anthropometrics, and motor outcomes were complex and inconsistent across studies. This review highlights key findings regarding the influence of anthropometric factors on physical capabilities in early childhood. Early identification of children with impaired growth or excessive adiposity may inform tailored interventions to promote optimal motor development and prevent issues like obesity. Creating supportive environments for healthy growth and age-appropriate physical activity opportunities is crucial during this critical developmental window.

13.
PLoS One ; 19(5): e0303888, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38787849

RESUMO

Combat sports, encompassing a range of activities from striking and grappling to mixed and weapon-based disciplines, have witnessed a surge in popularity worldwide. These sports are demanding, requiring athletes to harness energy from different metabolic pathways to perform short, high-intensity activities interspersed with periods of lower intensity. While it is established that the anaerobic alactic (ATP-PC) and anaerobic lactic systems are pivotal for high-intensity training sessions typical in combat sports, the precise contribution of these systems, particularly in varied training modalities such as single (SMT) and intermittent (IST) forms of the 30-second Wingate test, remains inadequately explored. This study aims at comparing performance outputs, physiological responses and gender differences during the SMT and IST forms of the 30-second Wingate test. Thirty-three highly trained combat sports athletes (17 women, 16 men; 10 boxing, 8 wrestling, 8 taekwondo and 7 karate) randomly performed SMT and IST. The IST consisted of three 10-second all-out attempts separated by 30 seconds of passive recovery, whereas the SMT was a single 30-second maximal effort. Resting, exercise and post-exercise oxygen uptake and peak blood lactate value were used to determine the metabolic energy demands via the PCr-LA-O2 method. The findings showed that total metabolic energy expenditure (TEE), ATP-PCr system contribution and the output of mechanical variables were higher in the IST than in the SMT form (all p<0.001). In contrast, the contribution of glycolytic and oxidative systems was higher in the SMT form (all p<0.001). However, exercise form and gender interaction were not significant (p>0.05). In combat sports, performance is not only determined by physiological and technical skills but also by metabolic energy input and efficiency. Therefore, our results can provide a comparison regarding the effects of exercise type and gender on metabolic energy metabolism to design the training of combat sports athletes.


Assuntos
Atletas , Metabolismo Energético , Ácido Láctico , Artes Marciais , Humanos , Feminino , Masculino , Artes Marciais/fisiologia , Adulto Jovem , Adulto , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Teste de Esforço/métodos , Consumo de Oxigênio/fisiologia , Boxe/fisiologia , Luta Romana/fisiologia , Fatores Sexuais
14.
Sci Rep ; 14(1): 14302, 2024 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-38906894

RESUMO

To assess the effects of warm-up music and low dose (3 mg·kg-1) of caffeine (CAF) on female taekwondo athlete's activity profile and psychophysiological responses during simulated combat. In a double-blinded, randomized, crossover study, 16 female athletes participated in simulated combats under one control and 5 experimental conditions [i.e., CAF alone (CAF), placebo alone (PL), CAF with music (CAF + M), PL with music (PL + M), and no supplement with music (M)]. After warming-up, athletes rated their felt arousal (FAS). Mean (HRmean) and peak (HRpeak) heart rate values were determined for each combat. After fighting, athletes rated their perceived exertion (RPE), feeling scale (FS), FAS, and physical enjoyment (PACES). Time-motion and technical-tactical variables were analyzed. CAF + M induced shorter skip and pause time, while attack time increased compared to other conditions (p < 0.05). Moreover, CAF + M increased single attacks, combined attacks, counter-attacks (p < 0.001), and defensive actions (p < 0.05) than other conditions. HRmean and HRpeak were lower under CAF + M than other conditions (p < 0.05). Additionally, higher FAS post-combat, FS, and PACES were observed under CAF + M, while RPE was lower (except CAF condition) compared to the other conditions (p < 0.05.Using CAF with warm-up music may increase combat cadence and improve the psychological state in female athletes more effectively than either strategy alone.


Assuntos
Atletas , Cafeína , Estudos Cross-Over , Frequência Cardíaca , Artes Marciais , Música , Humanos , Feminino , Cafeína/farmacologia , Cafeína/administração & dosagem , Música/psicologia , Atletas/psicologia , Artes Marciais/fisiologia , Adulto Jovem , Método Duplo-Cego , Frequência Cardíaca/efeitos dos fármacos , Exercício de Aquecimento , Adulto , Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Nível de Alerta/efeitos dos fármacos , Nível de Alerta/fisiologia
15.
Healthcare (Basel) ; 12(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38255054

RESUMO

The purpose of this study is to investigate the impact of different durations of Swedish massage on the static and dynamic balance at different times of the day in taekwondo athletes. Twelve taekwondo athletes who had been practicing on a regular basis for more than 5 years participated in this study. Taekwondo athletes completed static and dynamic balance tests either after a no-massage protocol (NMP), a five-minute massage protocol (5MMP), a ten-minute massage protocol (10MMP), or a fifteen-minute massage protocol (15MMP) two times a day in the morning (08:00-12:00) and in the evening (16:00-20:00), on non-consecutive days. The findings of this study suggest that the duration of the massage has a discernible impact on dynamic balance, particularly with regard to the right foot. Taekwondo athletes who received a 10MMP or 15MMP displayed significantly improved dynamic balance compared to those in the NMP. Importantly, these improvements were independent of the time of day when the massages were administered. It underscores the potential benefits of incorporating short-duration Swedish massages into taekwondo athletes' pre-competition routines to enhance dynamic balance. These findings highlight the potential benefits of incorporating short-duration Swedish massages into taekwondo athletes' pre-competition routines to enhance dynamic balance, a critical component of their performance, regardless of the time of day.

16.
PLoS One ; 19(5): e0304267, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38781263

RESUMO

BACKGROUND: Athletes in certain sports aim to gain an advantage by competing in a lower body mass class instead of competing in their own body mass class. This study aims to reveal certain physiologic and strength changes in elite male boxers who lost body mass rapidly before the competition. METHODS: 30 thirty boxers who were aged between 19-24 years and having a mean age of 7.4 years participated in the study. To evaluate the effect of short-term dietary intake interventions on body composition and muscle strength before the competition, boxers were divided into three groups: control (C), exercise+diet1 (E+D1) and exercise+diet2 (E+D2) groups. The dietary habits of the participants were controlled and they participated in the training program. The data of the study consisted of variables such as body mass, height, regional muscle mass, body fat percentage, biceps and femur bicondylar circumference measurements before the competitions. Isometric strength measurements of knee extensors and flexors and shoulder internal and external rotators were also recorded. RESULTS: Physiologic parameters such as body mass change, BMI level, body fat percentage and leg muscle ratios of E+D2 were significantly decreased compared to C and E+D1 groups. Furthermore, submaximal and maximal strength production in knee extensors and flexors as well as shoulder internal and external rotators were significantly decreased in E+D2 compared to C and E+D1 groups. CONCLUSION: The tendency to lose body mass quickly in a short of time may give the desired results in terms of BMI, body mass and fat percentage, but it may cause strength losses in boxers during the competition period.


Assuntos
Atletas , Composição Corporal , Boxe , Força Muscular , Redução de Peso , Humanos , Masculino , Força Muscular/fisiologia , Adulto Jovem , Boxe/fisiologia , Redução de Peso/fisiologia , Índice de Massa Corporal , Adulto , Músculo Esquelético/fisiologia , Exercício Físico/fisiologia , Desempenho Atlético/fisiologia
17.
Diagnostics (Basel) ; 14(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38472930

RESUMO

This study aims to develop an interpretable prediction model based on explainable artificial intelligence to predict bacterial sepsis and discover important biomarkers. A total of 1572 adult patients, 560 of whom were sepsis positive and 1012 of whom were negative, who were admitted to the emergency department with suspicion of sepsis, were examined. We investigated the performance characteristics of sepsis biomarkers alone and in combination for confirmed sepsis diagnosis using Sepsis-3 criteria. Three different tree-based algorithms-Extreme Gradient Boosting (XGBoost), Light Gradient Boosting Machine (LightGBM), Adaptive Boosting (AdaBoost)-were used for sepsis prediction, and after examining comprehensive performance metrics, descriptions of the optimal model were obtained with the SHAP method. The XGBoost model achieved accuracy of 0.898 (0.868-0.929) and area under the ROC curve (AUC) of 0.940 (0.898-0.980) with a 95% confidence interval. The five biomarkers for predicting sepsis were age, respiratory rate, oxygen saturation, procalcitonin, and positive blood culture. SHAP results revealed that older age, higher respiratory rate, procalcitonin, neutrophil-lymphocyte count ratio, C-reactive protein, plaque, leukocyte particle concentration, as well as lower oxygen saturation, systolic blood pressure, and hemoglobin levels increased the risk of sepsis. As a result, the Explainable Artificial Intelligence (XAI)-based prediction model can guide clinicians in the early diagnosis and treatment of sepsis, providing more effective sepsis management and potentially reducing mortality rates and medical costs.

18.
Children (Basel) ; 11(4)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38671676

RESUMO

CONTEXT: In today's ever-changing world, fostering personal and social responsibility is essential for building strong and compassionate communities. This study aimed to provide a quantitative synthesis focusing on the emotional and social outcomes of Teaching Personal and Social Responsibility (TPSR) model-based Physical Education (PE) programs. METHODS: A comprehensive literature review covering the period from November 2022 to September 2023 identified 637 articles published between 2005 and 2023. Of these, 20 met the inclusion criteria. Data from these articles were coded, and a comprehensive meta-analysis was conducted, incorporating 28 effect sizes. Methodological quality was assessed using the Medical Education Research Study Quality Instrument. Hedge's g served as the effect size measure and emotional and social outcomes subgroups were consolidated. Heterogeneity was evaluated with Cochran's Q and I2. Meta-regression and ANOVA-like models addressed categorical moderators, whereas publication bias was assessed through funnel plot, failsafe number, and Egger's linear regression. RESULTS: A significant and positive effect of the TPSR model on product outcomes (Hedge's g = 0.337, 95% CI = 0.199 to 0.476) was found. Despite considerable heterogeneity (I2 = 83.830), a random effects model was justified. Assessment of publication bias indicated a low likelihood. Moderator analyses revealed that publication countries significantly influenced the effect, with stronger effects in Turkey. Publication type (article vs. thesis) also played roles in moderation. The meta-regression analyses did not reveal significant effects for the grade level, duration of intervention, publication year or sample size on the TPSR model's impact on product outcomes. The TPSR model positively impacts emotional and social outcomes in PE, enhancing children' skills and behaviour. However, variations across cultures highlight the need for further research, considering limitations like language constraints and potential biases in study selection and data extraction.

19.
Front Nutr ; 11: 1322128, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38406182

RESUMO

Introduction: This investigation aims to elucidate the impact of Ramadan intermittent fasting on performance, physiological responses, and bioenergetic pathway contributions during repeated sprints. Methods: Fourteen active male Muslim athletes (age = 22.4 ± 1.8 years, body weight = 69.5 ± 3.8 kg, height = 176 ± 5.1 cm) executed a repeated sprint protocol, consisting of ten 20-meter sprints with 15-s passive recovery intervals, during both fasting and non-fasting conditions. The fasting session was conducted after a 12-14 h fast following Sahur (the pre-dawn meal during Ramadan). In contrast, the non-fasting session occurred before the Ramadan fasting period began, during the same hours of the day, at a time when fasting was not yet required for the athletes. Bioenergetic pathway contributions during repeated sprints were quantified using the PCr-LA-O2 method. Results: The mean sprint time during fasting sessions was 3.4 ± 0.3 s compared to 3.3 ± 0.2 s in non-fasting sessions, indicating a trend approaching the threshold of significance for slower times in the fasted state (p = 0.052, effect size (ES) = 0.34). In terms of bioenergetic contributions, the total metabolic energy expenditure (TEE) was slightly lower during fasting sessions (236.5 ± 22 kJ) compared to non-fasting sessions (245.2 ± 21.7 kJ), but this difference was not statistically significant (p = 0.102, ES = 0.40). Similarly, metabolic energy expenditure per sprint was 23.7 ± 2.2 kJ in fasting conditions compared to 24.5 ± 2.2 kJ in non-fasting conditions (p = 0.106, ES = 0.35). The oxidative energy contribution did not differ significantly between fasting (34.2 ± 4.1 kJ) and non-fasting conditions (34.2 ± 4.1 vs. 35.5 ± 5.2 kJ; p = 0.238, ES = 0.28). Similarly, lactic (60.4 ± 7.6 vs. 59.2 ± 8.3 kJ; p = 0.484, ES = 0.15); and alactic (149.3 ± 19.9 vs. 143 ± 21.5 kJ; p = 0.137, ES = 0.30) energy contributions showed no significant differences between the fasting and non-fasting sessions. The percentage of performance decrement (Pdec) and the percentage contributions of oxidative, lactic, and alactic pathways to the total energy expenditure did not differ significantly between the fasting and non-fasting conditions, indicating a similar bioenergetic profile across both conditions. Conclusion: The present findings indicate no significant differences in performance metrics and metabolic outcomes between fasted and non-fasted states. Future assessments with longer duration and higher intensity protocols may provide further insights.

20.
Front Sports Act Living ; 5: 1283296, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022779

RESUMO

The demands of the school day, which includes multiple lessons, require sustained attention from students; this can be challenging, especially for young children. Concentration of attention is a critical cognitive function that impacts learning. This study involved 129 healthy schoolchildren aged 8-10 years (spanning grades 2 and 3) from a regular secondary school in Kirov, Russian Federation. A "physical education minute" (PEM), consisting of various physical exercises, was introduced during the middle of a regular lesson for the experimental group (EG), while the control group (CG) continued with their regular studies. Concentration and attention were assessed before and after the PEM using the Bourdon test. The Bourdon test results indicated a significant decrease in concentration during the lesson for the CG (p < 0.001), while the EG exhibited significant improvement in concentration after the PEM (p < 0.001). The effect size was large, demonstrating a substantial impact of this break for physical activity on concentration. It can be concluded that implementing a set of exercises in the form of a PEM in the middle of a lesson significantly improves concentration among students aged 8-10. This study underscores the effectiveness of integrating short breaks for physical activity into the daily classroom routine, ultimately benefiting students' attention, learning, and overall educational experience. Further research could explore additional factors affecting concentration and the long-term effects of the PEM on cognitive development.

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