Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 87
Filtrar
2.
Sports (Basel) ; 12(4)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38668560

RESUMO

The scope of this pilot study was to assess the feasibility of using the laser imaging detection and ranging (LiDAR) technology for contactless 3D body scanning of sports athletes and deriving anthropometric measurements of the lower limbs using available software. An Apple iPad Pro 3rd Generation with embedded LiDAR technology in combination with the iOS application Polycam were used. The effects of stance width, clothing, background, lighting, scan distance and measurement speed were initially assessed by scanning the lower limbs of one test person multiple times. Following these tests, the lower limbs of 12 male and 10 female participants were scanned. The resulting scans of the lower limbs were complete for half of the participants and categorized as good in quality, while the other scans were either distorted or presented missing data around the shank and/or the thigh. Bland-Altman plots between the LiDAR-based and manual anthropometric measures showed good agreement, with the coefficient of determination from correlation analysis being R2 = 0.901 for thigh length and R2 = 0.830 for shank length, respectively. The outcome of this pilot study is considered promising, and a further refinement of the proposed scanning protocol and advancement of available software for 3D reconstruction are recommended to exploit the full potential of the LiDAR technology for the contactless anthropometric assessment of athletes.

3.
Sci Prog ; 107(2): 368504241239187, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567429

RESUMO

This study investigated the effects of match location, quality of opposition (classified into: strong [1st to 4th position]; intermediate [5th to 15th position]; weak [16th to 20th position]), and match outcome on the match running performance of starters and non-starters from a top elite Brazilian soccer team. Absolute measures were calculated using total distance, high-speed (19.8-25.2 km·h-1), sprinting (≥ 25.2 km·h-1), total distance high-acceleration (> 2m·s2), and deceleration (< -2m·s2) were recorded by GPS units from a sample of young soccer players (N = 25) in a total of 17 matches. Relative measures were calculated by dividing absolute measures by the total duration of the matches. Non-starters covered greater total distance (p = 0.02), sprinting (p = 0.02), high-acceleration and deceleration (p = 0.04), sprinting distance relative per minute played (p = 0.005), and high-acceleration and deceleration relative per minute played (p < 0.001) when the team plays at home, strong opponents, and wins the matches. Starters covered greater total distance in high-speed running (p = 0.04), high-acceleration and deceleration (p = 0.03), and high-speed running relative per minute played (p = 0.04) when the team plays strong opponents and wins the matches. These findings highlight the impact of contextual factors during matches on the locomotor performance of young soccer players.


Assuntos
Desempenho Atlético , Corrida , Futebol , Masculino , Humanos , Adolescente , Aceleração , Brasil
4.
Front Pediatr ; 12: 1285794, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38374876

RESUMO

Background: Cardiac troponin (cTn) is a reliable marker for evaluating myocardial damage. cTn is a very specific protein involved in myocardial injury, and it is a key factor in the diagnosis of coronary syndromes. Bibliometric analysis was applied in the present work, with the main goal of evaluating global research on the topic of cardiac troponin in pediatric populations. Methods: Publications about cardiac troponin and physical activity in pediatric populations were retrieved from the Social Sciences Citation Index (SSCI) and the Science Citation Index Expanded (SCIE) of the Web of Science Core Collection, and they were then analyzed. The study was able to identify the key bibliometric indicators, such as publications, keywords, authors, countries, institutions, and journals. For the analysis, VOSviewer, R-based Bibliometrix (4.2.2), and MapChart were used. Results: Initially, 98 documents were identified; however, once inclusion and exclusion criteria were applied, the number of documents decreased to 88. The search yielded 79 original research articles and 9 reviews, almost all of which were published in the past 2 decades. The total number of citations (Nc) of the retrieved publications was 1,468, and the average number of citations per article (Na) was 16.68. In general, 508 authors were found to have participated in research about troponin; they were associated with 256 institutions, and their work was published in 65 different journals from around the world. The authors hailed from 30 countries and/or regions. The year 2022 was the most productive year for the publication of the selected documents. The bibliometric analysis provided information regarding levels of cooperation among authors and institutions. In fact, China, the United States, and England were the most productive nations, and the journal with the greatest number of publications on the topic was Pediatric Cardiology. Summary: The number of publications and the trend line show that research on this topic has not yet reached a stage of maturity. There are referent investigators, countries, and institutions that have laid the foundations for subsequent studies on the analyzed topic.

5.
J Hum Kinet ; 89: 5-18, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38053963

RESUMO

Fluency is a movement parameter combining smoothness and hesitation, and its objective measurement may be used to determine the effects of practice on sports performance. This study aimed to measure fluency in parkour, an acrobatic discipline comprising complex non-cyclical movements, which involves fluency as a critical aspect of performance. Inter-individual fluidity differences between advanced and novice athletes as well as intra-individual variations of fluency between different parts and subsequent repetitions of a path were addressed. Seventeen parkour participants were enrolled and divided into two groups based on their experience. We analysed signals captured from an inertial measurement unit fixed on the back of the pelvis of each participant during three consecutive repetitions of a specifically designed parkour routine under the guidance of video analysis. Two fluency parameters, namely smoothness and hesitation, were measured. Smoothness was calculated as the number of inflexions on the so-called jerk graph; hesitation was the percentage of the drop in the centre of mass velocity. Smoothness resulted in significantly lower values in advanced athletes (mean: 126.4; range: 36-192) than in beginners (mean: 179.37; range: 98-272) during one of the three motor activities (p = 0.02). A qualitative analysis of hesitation showed that beginner athletes tended to experience more prominent velocity drops and negative deflection than more advanced athletes. In conclusion, a system based on a video and an inertial measurement unit is a promising approach for quantification and the assessment of variability of fluency, and it is potentially beneficial to guide and evaluate the training process.

6.
J Sports Sci ; : 1-6, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37722817

RESUMO

BACKGROUND: With increasing sports medicine content on social media, we sought to identify the top sports medicine influencers on X (formerly Twitter) and analyse their common characteristics. METHODS: X influence scores for "Sports Medicine" were collected in November 2021 from Right Relevance. Accounts were then screened in a blind, duplicate manner for personal and X profile characteristics. RESULTS: Physical therapists/physiotherapists made up 48% of the top sports science and medicine influencers. Locations in the U.S. and U.K. were listed for half of the influencers. The mean h-index was 30.2 (95% CI = [24.8-35.6]) with a median of 22.0 (range = 1-101). Most individuals reported multiple practice settings (63%), with 60% associated with an academic setting. Professional (62%) and Olympic (49%) level athletics were most frequently mentioned, with soccer (48%) and rugby (30%) as the most common sports. Among 76 profiles with URLs, most were linked to personal websites (57.9%). CONCLUSION: The top influencers on X consisted of accredited sports science and medicine professionals across various locations and occupations, providing ample networking and collaboration opportunities. The relatively high h-index in this study suggests sports science and medicine influencers on X are notable contributors to academic literature.

7.
Chronobiol Int ; 40(8): 1028-1038, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37525628

RESUMO

University students are commonly described as having worsened sleep quality, especially when inactive and Evening-type (E-type) subjects. This study aimed to examine the interactions between physical activity and chronotype on sleep quality among a sample of active Sports Science university students. In November 2019, 433 participants (mean age: 19.7 ± 1.56 years; 70% males) completed the Pittsburgh Sleep Quality Index, the Godin-Shepard Leisure-Time Physical Activity Questionnaire (tertiles categorisation), and the Morningness-Eveningness Questionnaire. Females and E-type slept significantly worse than males and Neither-(N-types) and Morning-types (M-types), respectively. However, there were no significant differences in sleep quality based on physical activity levels. The three-way ANOVA revealed that sleep quality in N- and E-types appeared to be independent of physical activity, whereas M-types showed an improvement in sleep classification with increased physical activity. Moderation analysis indicated that physical activity significantly moderated the relationship between chronotypes and sleep quality. Specifically, M-types demonstrated a more pronounced improvement in sleep quality with increasing physical activity compared to the other chronotypes. In conclusion, M-type university students derived the greatest benefits from physical activity in improving sleep quality. Conversely, physical activity seemed to have a limited impact on sleep quality among active E-type university students.


Assuntos
Ritmo Circadiano , Qualidade do Sono , Masculino , Feminino , Humanos , Adolescente , Adulto Jovem , Adulto , Universidades , Estudantes , Sono , Inquéritos e Questionários , Exercício Físico , Itália
8.
Front Nutr ; 10: 1169188, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37384105

RESUMO

Tyrosine metabolism has an intense role in the synthesis of neurotransmitters. Our study used an untargeted, sportomics-based analysis of urine samples to investigate changes in metabolism during a soccer match in 30 male junior professional soccer players. Samples were collected before and after the match and analyzed using liquid chromatography and mass spectrometry. Results showed significant changes in tyrosine metabolism. Exercise caused a downregulation of the homogentisate metabolites 4-maleylacetoacetate and succinylacetone to 20% (p = 4.69E-5) and 16% (p = 4.25E-14), respectively. 4-Hydroxyphenylpyruvate, a homogentisate precursor, was found to be upregulated by 26% (p = 7.20E-3). The concentration of hawkinsin and its metabolite 4-hydroxycyclohexyl acetate increased ~six-fold (p = 1.49E-6 and p = 9.81E-6, respectively). Different DOPA metabolism pathways were also affected by exercise. DOPA and dopaquinone increased four-to six-fold (p = 5.62E-14 and p = 4.98E-13, respectively). 3-Methoxytyrosine, indole-5,6-quinone, and melanin were downregulated from 1 to 25%, as were dopamine and tyramine (decreasing to up to 5% or 80%; p= 5.62E-14 and p = 2.47E-2, respectively). Blood TCO2 decreased as well as urinary glutathione and glutamate (40% and 10% respectively) associated with a two-fold increase in pyroglutamate. Our study found unexpected similarities between exercise-induced changes in metabolism and the inherited disorder Hawkinsinuria, suggesting a possible transient condition called exercise-induced hawkinsinuria (EIh). Additionally, our research suggests changes in DOPA pathways may be involved. Our findings suggest that soccer exercise could be used as a model to search for potential countermeasures in Hawkinsinuria and other tyrosine metabolism disorders.

9.
Percept Mot Skills ; 130(5): 2106-2122, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37291970

RESUMO

In this study, we sought to determine the prevalence of musculoskeletal injuries, perceived pain, and physical activity level among Brazilian practitioners of strength training (ST) and functional fitness (FF). Participants were 311 men and women who trained in 10 FF training centers and seven ST gyms. Each participant completed surveys of the prevalence of musculoskeletal injuries, their pain perception, and their physical activity level. A chi square test was used to analyze associations between groups and distributions of injuries. When any significant difference was observed, the difference score was analyzed through the adjusted residual values. Fisher's exact test was used to determined the associations between musculoskeletal injury prevalence and training modality (FF and ST) and between musculoskeletal injury prevalence and practice frequency (times/wk). To measure the magnitude of association between variables, the Phi coefficient was calculated for 2x2 associations and Cramer's V was used whenever the distributions were outside this standard. When the dependent variable presented a dichotomous characteristic, an Odds Ratio (OR) was calculated with a confidence interval of 95%. We found a higher musculoskeletal injury prevalence in the axial skeleton (n = 52; 83.88%) in FF practitioners and in the lower limbs of ST practitioners (n = 9; 52.96%). When the physical activity level cutoff point was set at 300 minutes per week, there was a significant relationship between physical activity and training modality (p = 0.005). There was also a significant association between pain perception and musculoskeletal injury (p < 0.001). Clinical follow-up was a protective factor to being injured (OR = 0.18; CI = 0.06-0.49), and, even after multivariate analysis this significant association was maintained (OR = 0.03; CI = 0.01 - 0.08). Thus, FF practitioners reported more musculoskeletal injuries than STs, and follow-up medical or physical therapy was a protective factor to these injuries. FF practitioners also had a higher level of weekly physical activity weekly than ST practitioners. Functional fitness practitioners may be at a higher risk of injuries than those who participate in traditional strength training.


Assuntos
Sistema Musculoesquelético , Masculino , Humanos , Feminino , Sistema Musculoesquelético/lesões , Prevalência , Brasil/epidemiologia , Exercício Físico , Percepção da Dor
10.
Artigo em Inglês | MEDLINE | ID: mdl-37239607

RESUMO

To solve the research-practice gap and take one step forward toward using big data with real-world evidence, the present study aims to adopt a novel method using machine learning to pool findings from meta-analyses and predict the change of countermovement jump. The data were collected through a total of 124 individual studies included in 16 recent meta-analyses. The performance of four selected machine learning algorithms including support vector machine, random forest (RF) ensemble, light gradient boosted machine, and the neural network using multi-layer perceptron was compared. The RF yielded the highest accuracy (mean absolute error: 0.071 cm; R2: 0.985). Based on the feature importance calculated by the RF regressor, the baseline CMJ ("Pre-CMJ") was the most impactful predictor, followed by age ("Age"), the total number of training sessions received ("Total number of training_session"), controlled or non-controlled conditions ("Control (no training)"), whether the training program included squat, lunge, deadlift, or hip thrust exercises ("Squat_Lunge_Deadlift_Hipthrust_True", "Squat_Lunge_Deadlift_Hipthrust_False"), or "Plyometric (mixed fast/slow SSC)", and whether the athlete was from an Asian pacific region including Australia ("Race_Asian or Australian"). By using multiple simulated virtual cases, the successful predictions of the CMJ improvement are shown, whereas the perceived benefits and limitations of using machine learning in a meta-analysis are discussed.


Assuntos
Atletas , Aprendizado de Máquina , Humanos , Austrália , Algoritmos , Redes Neurais de Computação
11.
Artigo em Inglês | MEDLINE | ID: mdl-37031854

RESUMO

Exercise physiologists and evolutionary biologists share a research interest in determining patterns of energy allocation during times of acute or chronic energetic scarcity. Within sport and exercise science, this information has important implications for athlete health and performance. For evolutionary biologists, this would shed new light on our adaptive capabilities as a phenotypically plastic species. In recent years, evolutionary biologists have begun recruiting athletes as study participants and using contemporary sports as a model for studying evolution. This approach, known as human athletic palaeobiology, has identified ultra-endurance events as a valuable experimental model to investigate patterns of energy allocation during conditions of elevated energy demand, which are generally accompanied by an energy deficit. This energetic stress provokes detectable functional trade-offs in energy allocation between physiological processes. Early results from this modelsuggest thatlimited resources are preferentially allocated to processes which could be considered to confer the greatest immediate survival advantage (including immune and cognitive function). This aligns with evolutionary perspectives regarding energetic trade-offs during periods of acute and chronic energetic scarcity. Here, we discuss energy allocation patterns during periods of energetic stress as an area of shared interest between exercise physiology and evolutionary biology. We propose that, by addressing the ultimate "why" questions, namely why certain traits were selected for during the human evolutionary journey, an evolutionary perspective can complement the exercise physiology literature and provide a deeper insight of the reasons underpinning the body's physiological response to conditions of energetic stress.


Assuntos
Evolução Biológica , Metabolismo Energético , Exercício Físico , Resistência Física , Humanos , Exercício Físico/fisiologia
12.
Front Physiol ; 14: 1089637, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36969605

RESUMO

The protection of physical activity (PA) against COVID-19 is a rising research interest. However, the role of physical activity intensity on this topic is yet unclear. To bridge the gap, we performed a Mendelian randomization (MR) study to verify the causal influence of light and moderate-to-vigorous PA on COVID-19 susceptibility, hospitalization, and severity. The Genome-Wide Association Study (GWAS) dataset of PA (n = 88,411) was obtained from the UK biobank and the datasets of COVID-19 susceptibility (n = 1,683,768), hospitalization (n = 1,887,658), and severity (n = 1,161,073) were extracted from the COVID-19 Host Genetics Initiative. A random-effect inverse variance weighted (IVW) model was carried out to estimate the potential causal effects. A Bonferroni correction was used for counteracting. The problem of multiple comparisons. MR-Egger test, MR-PRESSO test, Cochran's Q statistic, and Leave-One-Out (LOO) were used as sensitive analysis tools. Eventually, we found that light PA significantly reduced the risk of COVID-19 infection (OR = 0.644, 95% CI: 0.480-0.864, p = 0.003). Suggestive evidence indicated that light PA reduced the risks of COVID-19 hospitalization (OR = 0.446, 95% CI: 0.227 to 0.879, p = 0.020) and severe complications (OR = 0.406, 95% CI: 0.167-0.446, p = 0.046). By comparison, the effects of moderate-to-vigorous PA on the three COVID-19 outcomes were all non-significant. Generally, our findings may offer evidence for prescribing personalized prevention and treatment programs. Limited by the available datasets and the quality of evidence, further research is warranted to re-examine the effects of light PA on COVID-19 when new GWAS datasets emerge.

13.
Regen Ther ; 23: 1-7, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36942032

RESUMO

Introduction: Restrictions on financial gains from the sale of human body parts is a leading policy issue surrounding the use of human tissues and cells. However, discrepancies exist between regulations and reality. In stem cell research, in which diverse sources of tissues and cells can be used, unclear regulations can impede research. Thus, using the Japanese system as a case study, we examined the challenges in the implementation of the "no payment" or the mu-shou principle in stem-cell research over the years. Methods: We reviewed 28 Japanese laws and governmental guidelines and summarized the scope of restrictions on payments for the donation and supply of human biological samples (HBS). Results: As part of restrictions on financial rewards, the mu-shou principle emerged in Japanese laws and administrative documents in the 1990s. Although the Japanese mu-shou generally means "free" or "gratis" in English, its interpretation in research and development settings remains ambiguous. Traditionally, this principle was used to deny remuneration to donors. However, it is also inconsistently applied while processing and transferring human tissue after donation, which creates confusion among the various stakeholders. Recent policies have interpreted the principle in multiple ways: (1) treating the use of HBS for cell-processing as a non-profit activity; (2) a flexible interpretation of the principle to broaden the scope of user payments; and (3) removal of the principle itself to allow for commercial use. Conclusions: The inconsistencies in the monetary payment requirements for HBS could hinder research and development. After scrutinizing the principle's background, an effective approach is needed that considers the concerns of the providers, users, and society alike.

14.
Sports (Basel) ; 11(2)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36828318

RESUMO

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.

15.
Pensar Prát. (Online) ; 26Fev. 2023. Tab, Ilus
Artigo em Português | LILACS | ID: biblio-1526908

RESUMO

No esporte, a presença das mulheres no cargo de treinadora ainda é baixa. Assim, analisou-se qualitativamente as experiências esportivas e as pessoas relevantes na trajetória de alunas(os) até a disciplina Treinadores e Treinadoras Esportivos do curso de Ciências do Esporte da Universidade Estadual de Campinas. Utilizamos a Rappaport Timeline com 21 alunos e 8 alunas. As mulheres relataram influência de familiares e professoras(es) de Educação Física. Os homens apresentaram experiências positivas na escola. A representatividade e o acesso ao esporte foram favoráveis aos homens e desfavoráveis às mulheres. A menor presença de mulheres no curso, e como possíveis futuras treinadoras, está associada a uma trajetória de menos acessos e oportunidades de vivenciar o esporte ao longo da infância e juventude (AU).


In sport the presence of women in the position of coach is still low. The sports experiences and the relevant people in the trajectory of the students were qualitatively analyzed until the discipline Sports Coaches and Trainers of the Sport Sciences course at the Campinas State University. We used Rappaport Timeline with 21 male and 8 female students. The women reported the influence of family members and Physical Education teachers. Men had positive experiences at school. Representativeness and access to sport were favorable to men and unfavorable to women. The lower presence of women on the course and as possible future coaches is associated with a trajectory of less access and opportunities to experience the sport (AU).


En deporte la presencia de mujeres en los puestos de entrenador sigue siendo baja. Así analizamos cualitativamente las experiencias deportivas y las personas relevantes en la trayectoria de los estudiantes hasta la disciplina Entrenadores y Entrenadoras Deportivos de la carrera Ciencias del Deporte la Universidad Estadual de Campinas. Usamos Rappaport Timeline con 21 estudiantes varones y 8 mujeres. Las mujeres relataron la influencia de familiares y profesor(es) de Educación Física. Los hombres tuvieron experiencias positivas en la escuela. La representatividad y el acceso al deporte fueron favorables para los hombres y desfavorables para las mujeres. La menor presencia de mujeres en la cancha y como posibles futuras entrenadoras está asociada a una trayectoria de menor acceso y oportunidades para vivir el deporte (AU).


Assuntos
Humanos , Masculino , Feminino
16.
PeerJ ; 11: e14687, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36710857

RESUMO

Background: During counter movement jumps, adding weight in the eccentric phase and then suddenly releasing this weight during the concentric phase, known as accentuated eccentric loading (AEL), has been suggested to immediately improve jumping performance. The level of evidence for the positive effects of AEL remains weak, with conflicting evidence over the effectiveness in enhancing performance. Therefore, we proposed to theoretically explore the influence of implementing AEL during constrained vertical jumping using computer modelling and simulation and examined whether the proposed mechanism of enhanced power, increased elastic energy storage and return, could enhance work and power. Methods: We used a simplified model, consisting of a ball-shaped body (head, arm, and trunk), two lower limb segments (thigh and shank), and four muscles, to simulate the mechanisms of AEL. We adjusted the key activation parameters of the muscles to influence the performance outcome of the model. Numerical optimization was applied to search the optimal solution for the model. We implemented AEL and non-AEL conditions in the model to compare the simulated data between conditions. Results: Our model predicted that the optimal jumping performance was achieved when the model utilized the whole joint range. However, there was no difference in jumping performance in AEL and non-AEL conditions because the model began its push-off at the similar state (posture, fiber length, fiber velocity, fiber force, tendon length, and the same activation level). Therefore, the optimal solution predicted by the model was primarily driven by intrinsic muscle dynamics (force-length-velocity relationship), and this coupled with the similar model state at the start of the push-off, resulting in similar push-off performance across all conditions. There was also no evidence of additional tendon-loading effect in AEL conditions compared to non-AEL condition. Discussion: Our simplified simulations did not show improved jump performance with AEL, contrasting with experimental studies. The reduced model demonstrates that increased energy storage from the additional mass alone is not sufficient to induce increased performance and that other factors like differences in activation strategies or movement paths are more likely to contribute to enhanced performance.


Assuntos
Músculo Esquelético , Tendões , Músculo Esquelético/fisiologia , Movimento/fisiologia , Postura , Extremidade Inferior
17.
Sports (Basel) ; 11(1)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36668715

RESUMO

Complex contrast training (CCT) is an exercise modality that utilizes both high-load resistance activity and low-load plyometric activity in a set-by-set fashion within a single exercise session. Such a combination of exercises targets multiple aspects of the force−velocity curve and may thus lead to improvement of various components of physical fitness. However, no previous study has attempted to compare the effects of load-equated two vs. three CCT sessions per week on measures of physical fitness. Forty-five male participants aged 21.4 ± 2.0 years were randomly assigned to either two weekly CCT sessions (CCT-2; n = 15), three weekly CCT sessions (CCT-3; n = 15), or an active control group (CG; n = 15). Selected measures of physical fitness were assessed pre- and post-six weeks of training. The tests included the assessment of 15 and 30 m linear sprint speeds, upper (medicine ball throw) and lower limb muscle power (standing long jump and countermovement jump with arm thrust), muscle strength (isokinetic peak knee extensor/flexor torque), and change-of-direction speed (modified agility T-test (MAT)). Significant group−time interactions were observed for all dependent variables (all p < 0.001, ɳp2 = 0.51−0.78) using ANOVA. Post hoc tests indicated significant performance improvements for the CCT-2 and CCT3 groups for all dependent variables (Hedge's g = 0.28−3.26, %Δ = 2.4−16.7), including the 15 and 30 m linear sprint speeds (p < 0.001), medicine ball throw (p < 0.001), standing long jump (p < 0.001), countermovement jump with arm thrust (p < 0.001), right leg knee extensor (p < 0.001) and flexor peak torque (p < 0.001), left leg knee extensor (p < 0.001) and flexor peak torque (p < 0.001), and change-of-direction speed (p < 0.001). The CCT-3 group showed greater improvements in MAT compared to the CCT-2 group (g = 3.26 vs. 0.70, p < 0.001). In conclusion, compared to active controls, the load-equated CCT-2 and CCT-3 programs provided similar effects on measures of physical fitness in active adult males. However, an athlete's goal is to improve their MAT score, the CCT-3 program may elicit greater improvements compared with the CCT-2 program.

18.
Jpn J Ophthalmol ; 67(2): 175-181, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36708418

RESUMO

PURPOSE: There are only a few epidemiological studies of dry eye syndrome (DES) in populations with a common academic background. in this study, the prevalence of DES and associated factors were evaluated separately in men and women physical education and sports science graduates. STUDY DESIGN: Cross-sectional survey. METHODS: A questionnaire about the diagnosis of DES and associated factors was mailed to 9507 graduates of the Faculty of Health and Sports Science, Juntendo University. The questions covered subjective DES using Schaumberg et al.'s questionnaire and the prevalence of diagnosed DES. Associated factors, age, sex, smoking, alcohol consumption, body mass index, daily screen viewing time, and contact lens (CL) use were analyzed. RESULTS: A total of 2048 valid responses were received. The prevalence of diagnosed DES was 2.9% in men and 9.3% in women. For subjective DES, the prevalence was 14.8% in men and 39.8% in women. The odds ratio for DES was high in men and women who used CLs and women whose daily screen viewing time was ≥ 4 h. CONCLUSION: Both diagnosed and subjective DES were highly prevalent in men and women of all ages, particularly among those in their 20 and 30s. CL use was associated with DES in both men and women. Measures to deal with the factors that can be corrected might have a positive effect on the ocular health and quality of life of physical education and sports science graduates.


Assuntos
Síndromes do Olho Seco , Qualidade de Vida , Masculino , Humanos , Feminino , Estudos Transversais , Prevalência , Educação Física e Treinamento , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/epidemiologia , Fatores de Risco , Inquéritos e Questionários
19.
Healthcare (Basel) ; 11(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36673577

RESUMO

Our paper, which is the first historical study about heat injuries in Singapore, seeks to situate the Singapore Armed Forces' (SAF) history of heat stress management policies within the national context. Firstly, we observe that since the late 1970s, a research-driven approach has been adopted by the SAF's military medical leaders to formulate a range of policies to address the Forces' high incidence of heat injuries. This has resulted in the introduction of SAF-wide training measures, and the assembling of local scientific research expertise, which has led to a sharp reduction in heat injury incidence from the 1980s to 2000s. Through this, the SAF sought to demonstrate that its heat stress mitigation measures made the Singapore military 'heat proof'. Secondly, the state shaped a soldier safety agenda in the late 2000s on the back of an increasing emphasis on safety and the transformation of the SAF into a highly-educated and technologically-sophisticated force. This meant a shift towards concern about the welfare of every soldier, particularly through the state's drive to eradicate all training-related deaths. Accordingly, the SAF medical military leaders responded to the state's safety agenda by introducing heat stress management research and policies that were oriented towards the target of eradicating deaths due to heat stress. This policy and research direction, as such, has been strongly guided by the state's safety agenda and utilised to demonstrate to the public that all efforts have been taken to comprehensively mitigate the risks of heat.

20.
Crit Rev Food Sci Nutr ; 63(20): 4785-4798, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34845944

RESUMO

Creatine (CRE) and caffeine (CAF) have been used as ergogenic aids to improve exercise performance. The present study reviewed the current evidence supporting the additional use of CAF intake during or after the CRE loading on exercise performance. The search was carried out in eight databases, with the methodological quality of the studies assessed via the QualSyst tool. From ten studies that met the criteria for inclusion, six had strong, three moderate, and one weak methodological quality. CAF was ingested ∼1 h before the performance trial (5-7 mg.kg-1) after a CRE loading period (5-6 days with 0.3 g.kg-1.d-1) in five studies, with the combination CAF + CRE providing additional ergogenic effect compared to CRE alone in three of these studies. Furthermore, CAF was ingested daily during the CRE loading protocol in five studies, with CAF showing additive benefits compared to CRE alone only in one study (3 g.d-1 of CRE during 3 days + 6 mg.kg-1 of CAF for 3 days). The combination CAF + CRE seems to provide additional benefits to exercise performance when CAF is acutely ingested after a CRE loading. There is, however, no apparent benefit in ingesting CAF during a CRE loading period.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2021.2007470.


Assuntos
Cafeína , Creatina , Cafeína/farmacologia , Creatina/farmacologia , Método Duplo-Cego , Exercício Físico , Ingestão de Alimentos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...