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1.
J Sports Med Phys Fitness ; 64(3): 255-264, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37987711

RESUMO

BACKGROUND: The aim of this study was to assess the effectiveness of a new Short Intermittent Taekwondo Test (SITT) in 17 black belt athletes. METHODS: Maximal oxygen uptake (V̇O2max), carbon dioxide production (V̇CO2), respiratory exchange ratio (RER), heart rate (HR), and blood lactate concentration [La]+ during treadmill cardiopulmonary exercise test (CPET) and SITT were compared. SITT started with 10 sec of all-out kicks, alternating legs, and progressively increasing 5 s on each stage until the 4th stage. After the 4th stage the participants performed 25 s of turning kicks (Dolleo chagi), on each stage until the last (10th stage). The passive recovery phase after the 4th and the 7th stage lasted 30 s. RESULTS: V̇O2max and maximal HRmax were not significantly different (P=0.85 vs. P=0.76) between tests, while RER and [La]+ were significantly higher in SITT than in CPET (P=0.002 vs. P=0.001). No difference in RPE (P=0.84) was found. A significant positive correlation between two tests for V̇O2max and HRmax was found. CONCLUSIONS: Our findings showed that SITT induces physiological responses like CPET suggesting that it can be used to assess aerobic power in national taekwondo athletes, thus helping coaches to select correctly training intensities and monitor athletes' aerobic performance along the training phases.


Assuntos
Teste de Esforço , Consumo de Oxigênio , Humanos , Consumo de Oxigênio/fisiologia , Ácido Láctico , Frequência Cardíaca/fisiologia , Atletas , Metaboloma
2.
J Mot Behav ; 56(2): 132-138, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37828754

RESUMO

Newly acquired motor skills can be critically driven by different rest periods during practice. Specifically, in the initial stages of motor skill acquisition, the interval between individual trials plays a pivotal role in facilitating effective motor performance, such as in the case of throwing. The objective of this research was to determine the optimal inter-trial rest period promoting efficient motor performance, focusing on two specific motor task actions. In a randomized counterbalanced cross-over research design 169 high-school students aged 14 were studied (M = 150; F = 19). In one block, participants performed 10 basketball free throws with a short rest interval (< 5 s) and 10 other throws with a long rest interval (∼50-60 s). In a second block, they threw a regular size tennis ball into a 1-m diameter circle on the floor at 6.75 m, again throwing 10 times with a short inter-trial rest interval and 10 times with a long inter-trial rest interval. The order of the rest intervals within each block was randomized and counterbalanced. With a repeated measures two-way analysis of variance, greater accuracy seemed to be associated with short intra-set rest intervals as there were significant main effects of both conditions (F1,167 = 368.0, p < 0.001, η2p = 0.271) and resting time (F1,167 = 18.6, p < 0.001, η2p = 0.192) and no significant interaction "condition by time". Fast practice was efficient independently of the complexity of the throwing task, suggesting robust support for schema theory.


Assuntos
Aprendizagem , Destreza Motora , Humanos , Adolescente , Projetos de Pesquisa
3.
Rev Esp Salud Publica ; 972023 Dec 11.
Artigo em Espanhol | MEDLINE | ID: mdl-38087956

RESUMO

OBJECTIVE: The first COVID-19 lockdown was a very restrictive situation that may have impacted on the prevalence and patterns of cannabis use. The aim of this systematic review was to assess the evidence on cannabis use and reasons for use in different countries during first lockdown in young adults and general population. METHODS: This study followed PRISMA guidelines, and the review protocol was registered in PROSPERO (registration CRD42022303181). The search was carried out in PubMed, Scopus, Web of Science y Embase databases. Inclusion criteria were: cross-sectional or cohort studies; population ≥16 years; exploring cannabis use during lockdown; and English or Spanish language. RESULTS: Thirty studies, conducted in European countries (n=17), North America (n=12) and rest of the world (n=1), were analysed. The overall prevalence of cannabis use was found to be largely unchanged, but regular users tended to maintain (between 39.5% and 96.8% of the sample) or increase cannabis use (between 2.9% and 51.6%). The main decreases were among occasional users. Some reasons for the increase were boredom, loneliness, stress, coping and depressive symptoms. In addition, young people were the heaviest users, and being younger, live without family, financial problems and a low educational level were significantly (p-value<0.05) associated with increased use. CONCLUSIONS: Most regular users maintained or slightly increased their use, with young people being the main users. Concerning reasons for use like coping and depressive symptoms were found. Cannabis use needs to be addressed with strategies focused on the young population, considering occasional and regular use, as well as motivations.


OBJETIVO: El primer confinamiento por la COVID-19 fue una situación muy restrictiva que pudo haber impactado sobre la prevalencia y los patrones de consumo de cannabis. El objetivo de esta revisión sistemática fue evaluar la evidencia sobre el consumo y los motivos de consumo de cannabis en diferentes países durante el primer confinamiento en adultos jóvenes y población general. METODOS: Este estudio siguió las directrices PRISMA y el protocolo de revisión se registró en PROSPERO (registro CRD42022303181). Se realizó una búsqueda en las bases de datos PubMed, Scopus, Web of Science y Embase en julio de 2023. Los criterios de inclusión fueron: estudios transversales o de cohortes; población con edad igual o mayor de 16 años; explorar el consumo durante el confinamiento; e idioma inglés o español. RESULTADOS: Se analizaron treinta estudios, realizados en países europeos (n=17), norteamericanos (n=12) y resto del mundo (n=1). Se observó que la prevalencia global de consumo de cannabis no experimentó grandes cambios, pero los consumidores regulares tendieron a mantener (entre el 39,5% y el 96,8% de la muestra) o a incrementar el consumo (entre el 2,9% y el 51,6%). Las principales disminuciones se dieron en consumidores ocasionales. Algunos motivos para el aumento fueron aburrimiento, soledad, estrés, afrontamiento y síntomas depresivos. Además, los jóvenes fueron los mayores consumidores y ser más joven, vivir sin la familia, los problemas financieros y un bajo nivel de estudios se asociaron significativamente (p-valor menor de 0,05) con el aumento del consumo. CONCLUSIONES: La mayor parte de consumidores regulares mantuvieron o aumentaron ligeramente su consumo, siendo los jóvenes los principales consumidores. Se encontraron motivos de consumo alarmantes como el afrontamiento y los síntomas depresivos. Es necesario que el consumo de cannabis se aborde con estrategias enfocadas en la población joven, considerando el consumo ocasional y regular, así como las motivaciones.


Assuntos
COVID-19 , Cannabis , Humanos , Adulto Jovem , Adolescente , COVID-19/epidemiologia , Estudos Transversais , Pandemias , Controle de Doenças Transmissíveis , Espanha
4.
Eur J Investig Health Psychol Educ ; 13(11): 2561-2573, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37998068

RESUMO

The phenomenon of doping is a public health issue that poses threats to sport and society. In recent decades, the emphasis on efforts to address the issue and reduce the incidence of doping by young people in sport has shifted from deterrence through testing and punishment to the promotion of clean sport behaviours through values-based education. The "I Run Clean project" sought to develop new and effective tools targeting grassroots athletes and those around them (coaches, medical support personnel, sport leaders, parents). These included sport-specific e-learning and in-person peer-to-peer workshops led by trained volunteer ambassadors. The aim of all "I Run Clean" measures is to go beyond the warnings and provision of factual information about early anti-doping campaigns to a more holistic educational approach that focuses participants on their personal and sport-related values in order to encourage good decision-making and resistance to doping-related behaviours. This study evaluates the efficacy of the peer-to-peer workshops and their impact on selected psycho-social variables. The collaboration of the volunteer ambassadors is shown to effectively transmit the desired reasoning, reduce doping risk factors and enhance protective factors.

5.
PLoS One ; 18(11): e0288700, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37992064

RESUMO

The purpose of this study was to investigate the effects of partial-body cryostimulation on middle-distance runners before two 3000-m tests at the speed of the first and second ventilatory threshold, and before a time to exhaustion test at 110% of the maximal aerobic speed. Twelve amateur runners (age: 46 ± 9 years; VO2max: 51.7 ± 4.9 ml·kg-1·min-1) completed six running testing sessions in a randomized counterbalanced cross-over fashion: three of them were preceded by a partial-body cryostimulation and the other three by a control condition. The testing sessions consisted of: 1) a 3000-m continuous running test at the speed of the first ventilatory threshold; 2) a 3000-m continuous running test at the speed of the second ventilatory threshold; 3) a time to exhaustion test at 110% of the maximal aerobic speed. Heart rate, ratings of perceived exertion and visual analogue scale relative to muscle pain were recorded throughout the tests. Total quality recovery was evaluated 24-48 h after the end of each test. Distance to exhaustion was higher after partial-body cryostimulation than control condition (p = 0.018; partial-body cryostimulation: 988 ± 332 m, control: 893 ± 311 m). There were differences in the ratings of perceived exertion during each split of the 3000-m continuous running test at the speed of the second ventilatory threshold (p = 0.001). Partial-body cryostimulation can be positively considered to enhance middle-distance running performance and reduce perception of effort in amateur runners.


Assuntos
Vacinas Anticâncer , Corrida , Adulto , Humanos , Pessoa de Meia-Idade , Atletas , Frequência Cardíaca/fisiologia , Consumo de Oxigênio/fisiologia , Corrida/fisiologia , Fatores de Tempo , Estudos Cross-Over
7.
Int J Sports Physiol Perform ; 18(12): 1412-1419, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37730209

RESUMO

PURPOSE: Few data are available on sleep characteristics of elite track-and-field athletes. Our study aimed to assess (1) differences in sleep between sexes and among different track-and-field disciplines, (2) the effect of individualized sleep-hygiene strategies on athletes' sleep parameters, and (3) daytime nap characteristics in track-and-field athletes. METHODS: Sleep characteristics of 16 elite Olympic-level track-and-field athletes (male: n = 8; female: n = 8) were assessed during the preseason period, at baseline (T0), and during the in-season period, after the adoption of individualized sleep-hygiene strategies (T1). Sleep parameters were objectively monitored by actigraphy for a minimum of 10 days, for each athlete, at both T0 and T1. A total of 702 nights were analyzed (T0 = 425; T1 = 277). RESULTS: Female athletes displayed better sleep efficiency (88.69 [87.69-89.68] vs 91.72 [90.99-92.45]; P = .003, effect size [ES]: 0.44), lower sleep latency (18.99 [15.97-22.00] vs 6.99 [5.65-8.32]; P < .001, ES: 0.65), higher total sleep time (07:03 [06:56-07:11] vs 07:18 [07:10-07:26]; P = .030, ES: 0.26), earlier bedtime (00:24 [00:16-00:32] vs 00:13 [00:04-00:22]; P = .027, ES: 0.18), and lower nap frequency (P < .001) than male athletes. Long-distance runners had earlier bedtime (00:10 [00:03-00:38] vs 00:36 [00:26-00:46]; P < .001, ES: 0.41) and wake-up time (07:41 [07:36-07:46] vs 08:18 [08:07-08:30]; P < .001, ES: 0.61), higher nap frequency, but lower sleep efficiency (88.79 [87.80-89.77] vs 91.67 [90.95-92.38]; P = .013, ES: 0.44), and longer sleep latency (18.89 [15.94-21.84] vs 6.69 [5.33-8.06]; P < .001, ES: 0.67) than athletes of short-term disciplines. Furthermore, sleep-hygiene strategies had a positive impact on athletes' total sleep time (429.2 [423.5-434.8] vs 451.4 [444.2-458.6]; P < .001, ES: 0.37) and sleep latency (14.33 [12.34-16.32] vs 10.67 [8.66-12.68]; P = .017, ES: 0.19). CONCLUSIONS: Sleep quality and quantity were suboptimal at baseline in Olympic-level track-and-field athletes. Large differences were observed in sleep characteristics between sexes and among different track-and-field disciplines. Given the positive effect of individualized sleep-hygiene strategies on athlete's sleep, coaches should implement sleep education sessions in the daily routine of top-level athletes.


Assuntos
Distinções e Prêmios , Atletismo , Humanos , Masculino , Feminino , Tóquio , Sono , Atletas , Higiene
8.
J Sports Med Phys Fitness ; 63(12): 1254-1261, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37535342

RESUMO

BACKGROUND: Poor information is available regarding real field data on the different factors that could have an influence on curve sprint and its association with anthropometric and strength parameters. METHODS: We designed a crossover pilot-study that enrolled 14 track and field athletes of 200 and 400 m (8/14 men, age: 20.5±2.3 years, height: 1.73±0.06 m; body mass: 60.5±6.2 kg) that performed randomly in two different days assessment of anthropometric parameters, jump test by squat jump (SJ) and triple hop distance (THD), performance during a 20-m curve sprint (day 1), and assessment of 1RM for right and left limb on Bulgarian split squat (BSS) (day 2). The unpaired t test and Pearson's correlation were used for data analysis. RESULTS: No statistical differences for anthropometric and strength parametric parameters between right and left lower limbs were observed. Twenty-meter curve sprints were negatively associated with body mass (P=0.0059, R=-0.7) and Body Mass Index (BMI; P=0.032, R=0.6). Moreover, a negative association was observed with SJ height (P=0.0025, R=-0.7), speed (P=0.0028; R=-0.7), strength (P=0.009, R=-0.7) and power (P=0.009, R=-0.7). Finally, 20-m curve sprint negatively correlated with right (P=0.0021, R=-0.7) and left (P<0.0001, R=-0.9) THD and 1 RM right (P=0.025, R=-0.6;) and left (P=0.0049, R=-0.7) BSS, respectively. CONCLUSIONS: This pilot study demonstrated that 20-m curve sprint was negatively associated with body mass, BMI, vertical jump performance, THD and 1RM BSS. This information could be useful to coaches and sport scientists as a reference value to improve athlete performance for 200- and 400-m athletes.


Assuntos
Desempenho Atlético , Corrida , Atletismo , Masculino , Humanos , Adolescente , Adulto Jovem , Adulto , Projetos Piloto , Força Muscular
9.
PLoS One ; 18(7): e0286958, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37437057

RESUMO

BACKGROUND: Although physical activity (PA) has been recognized as a favourable factor in the prevention of various diseases, including certain forms of cancer, the relationship between PA and gastric cancer (GC) is not yet fully understood. This study aims to provide data from a pooled analysis of case-control studies within the Stomach cancer Pooling (StoP) Project to estimate the association between leisure-time PA and the occurrence of GC. METHODS: Six case-control studies from StoP project collected data on leisure-time PA, for a total of 2,343 cases and 8,614 controls. Subjects were classified into three leisure-time PA categories, either none/low, intermediate or high, based on study-specific tertiles. We used a two-stage approach. Firstly, we applied multivariable logistic regression models to obtain study-specific odds ratios (ORs) and corresponding 95% confidence intervals (CIs) then, we used a random-effect models to obtain pooled effect estimates. We performed stratified analyses according to demographic, lifestyle and clinical covariates. RESULTS: The meta-analysis showed ORs of GC with no significant differences between intermediate vs low and high vs low PA level (OR 1.05 [95%CI 0.76-1.45]; OR 1.23 [95%CI 0.78-1.94], respectively). GC risk estimates did not strongly differ across strata of selected covariates except for age ≤ 55 years old (high vs low level: OR 0.72 [95%CI 0.55-0.94]) and for control population-based studies (high vs low level: OR 0.79 [95%CI 0.68-0.93]). CONCLUSIONS: No association was found between leisure time PA and GC, apart from a slight suggestion of decreased risk below age 55 and in control population-based studies. These results may reflect specific characteristics of GC at a younger age, or the presence of a cohort effect mediating and interacting with socioeconomic determinants of GC The different distribution of PA levels among hospitalized controls could have led to an underestimated effect of PA on GC risk.


Assuntos
Neoplasias Gástricas , Humanos , Pessoa de Meia-Idade , Neoplasias Gástricas/epidemiologia , Atividade Motora , Exercício Físico , Atividades de Lazer
10.
J Therm Biol ; 115: 103620, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37364442

RESUMO

Partial Body Cryostimulation (PBC) involves a very cold air flow directed to the body of subjects with minimal clothing. PBC is performed in a rapid timeframe, inside an on-purposed designed cryo-cabin. Recently, cryo-cabins have been built with different energy systems, however a validation study on relative thermal responses is missing. This study was aimed at comparing thermal responses following a PBC in an electrically powered cryo-cabin based on forced convection or into a standard nitrogen-fueled cryo-cabin. In a randomized crossover fashion, thirty-six subjects (F=20; M=16) underwent both cryo-exposures lasting 150 s each. Thermal responses were assessed before and immediately after completing each PBC session. Mixed model analysis of variance revealed a significantly colder temperature after electric PBC in all the body regions (except for the thighs) with respect to a standard nitrogen based PBC (F: 16.4 ± 1.4 vs 18 ± 5.8 °C; M: 16.4 ± 1.7 vs 20.9 ± 4 °C). Moreover, a significant lower thermal discomfort was perceived at the end of electric PBC as compared to that one felt following standard PBC. For the first time, the safety and thermo-effectiveness of an electric cryo-cabin based on forced convection was ensured. This methodology can be viable for practitioners of PBC and clinicians.


Assuntos
Temperatura Baixa , Convecção , Humanos
11.
Scand J Med Sci Sports ; 33(5): 712-724, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36601789

RESUMO

The main purpose was to compare by each training the mental load and fatigue reported by semiprofessional soccer players comparing between regular season phase and the play-offs. Fifty-three players (Mage  = 24.59 years) for two teams participated during the 2020/21 season. Mental load was measured with a Likert questionnaire. Mental fatigue was quantified with a Visual Analogue Scale. Four trainings were recorded each week (Monday = MD+1, Wednesday = MD-4, Thursday = MD-3 and Saturday = MD-1), with a competitive match on Sunday across 10 weeks (five dates of regular season - five dates of play-offs). A Linear Mixed Model was performed with R-studio, using the training days and the competitive phase as independent variables. The influence of time played as co-variable was also checked. Results showed MD+1 as the more mentally fatiguing day in both phases, although MD-4 were the training with higher mental load reported (p = 0.001). Comparing phases, mental fatigue was significantly higher during the play-offs (p = 0.037). With regard time played, players that did not usually play showed a decrease in mental load during the play-offs. Then, we recommend coaches to use recovery strategies for mental fatigue, avoid mentally fatiguing tasks close to competition and considerer the time played as a factor which may contribute to individual differences in player mental fatigue.


Assuntos
Condicionamento Físico Humano , Futebol , Humanos , Adulto Jovem , Adulto , Estações do Ano , Modelos Lineares , Inquéritos e Questionários
13.
Front Physiol ; 14: 1334766, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38344385

RESUMO

Background: A training program can stimulate physiological, anatomical, and performance adaptations, but these improvements can be partially or entirely reversed due to the cessation of habitual physical activity resulting from illness, injury, or other influencing factors. Purpose: To investigate the effects of detraining on cardiorespiratory, metabolic, hormonal, muscular adaptations, as well as short-term and long-term performance changes in endurance athletes. Methods: Eligible studies were sourced from databases and the library up until July 2023. Included studies considered endurance athletes as subjects and reported on detraining duration. Results: Total cessation of training leads to a decrease in VO2max due to reductions in both blood and plasma volume. Cardiac changes include decreases in left ventricular mass, size, and thickness, along with an increase in heart rate and blood pressure, ultimately resulting in reduced cardiac output and impaired performance. Metabolically, there are declines in lactate threshold and muscle glycogen, increased body weight, altered respiratory exchange ratio, and changes in power parameters. In the short term, there is a decrease in insulin sensitivity, while glucagon, growth hormone, and cortisol levels remain unchanged. Skeletal muscle experiences reductions in arterial-venous oxygen difference and glucose transporter-4. Implementing a partial reduction in training may help mitigate drastic losses in physiological and performance parameters, a consideration when transitioning between training seasons. Conclusion: There is a dearth of data investigating the detraining effects of training reduction/cessation among endurance athletes. Delving deeper into this topic may be useful for professionals and researchers to identify the optimal strategies to minimize these effects.

14.
PLoS Genet ; 18(11): e1010483, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36374919

RESUMO

The target of the rapamycin (TOR) signaling pathway plays a negative role in controlling virulence in phytopathogenic fungi. However, the actual targets involved in virulence are currently unknown. Using the corn smut fungus Ustilago maydis, we tried to address the effects of the ectopic activation of TOR on virulence. We obtained gain-of-function mutations in the Rheb GTPase, one of the conserved TOR kinase regulators. We have found that unscheduled activation of Rheb resulted in the alteration of the proper localization of the pheromone receptor, Pra1, and thereby pheromone insensitivity. Since pheromone signaling triggers virulence in Ustilaginales, we believe that the Rheb-induced pheromone blindness was responsible for the associated lack of virulence. Strikingly, although these effects required the concourse of the Rsp5 ubiquitin ligase and the Art3 α-arrestin, the TOR kinase was not involved. Several eukaryotic organisms have shown that Rheb transmits environmental information through TOR-dependent and -independent pathways. Therefore, our results expand the range of signaling manners at which environmental conditions could impinge on the virulence of phytopathogenic fungi.


Assuntos
Ustilago , Ustilago/genética , Feromônios/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/genética , Proteína Enriquecida em Homólogo de Ras do Encéfalo/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Zea mays/metabolismo , Fungos/metabolismo , Cegueira , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
15.
Cancers (Basel) ; 14(18)2022 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36139578

RESUMO

Aldehyde dehydrogenase 1A1 (ALDH1A1) is a cancer stem cell (CSC) marker related to clinical outcomes in breast cancer (BC). The aim of this study was to analyze the relationship between ALDH1A1, programmed death ligand 1 (PD-L1) and tumor-infiltrating lymphocytes (TILs) in triple negative (TN) and human epidermal growth factor receptor 2-positive (HER2+) BC tumors, and its association with clinicopathological characteristics and outcomes. A retrospective, historical cohort study of patients diagnosed with early or locally advanced BC treated with neoadjuvant chemotherapy was conducted. ALDH1A1, PD-L1 expression and TILs were assessed using immunohistochemistry. A total of 75 patients were analyzed (42.7% TN, 57.3% HER2+ tumors). ALDH1A1+ was related to HTILs (p = 0.005) and PD-L1+ tumors (p = 0.004). ALDH1A1+ tumors presented higher CD3+ (p = 0.008), CD4+ (p = 0.005), CD8+ (p = 0.003) and CD20+ (p = 0.006) TILs. ALDH1A1+ (p = 0.018), PD-L1+ (p = 0.004) and HTILs (p < 0.001) were related to smaller tumors. ALDH1A1+ was related to pathologic complete response (pCR) (p = 0.048). At the end of the follow-up (54.4 [38.3−87.6] months), 47 patients (62.7%) remained disease-free, and 20 (26.7%) had died. HTILs were related to improved disease-free survival (p = 0.027). ALDH1A1+ was related to PD-L1+ and HITLs, that might be related to higher pCR rates with neoadjuvant therapy.

16.
Environ Int ; 169: 107525, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36150295

RESUMO

BACKGROUND: Toenails are commonly used as biomarkers of exposure to zinc (Zn), but there is scarce information about their relationship with sources of exposure to Zn. OBJECTIVES: To investigate the main determinants of toenail Zn, including selected sources of environmental exposure to Zn and individual genetic variability in Zn metabolism. METHODS: We determined toenail Zn by inductively coupled plasma mass spectrometry in 3,448 general population controls from the MultiCase-Control study MCC-Spain. We assessed dietary and supplement Zn intake using food frequency questionnaires, residential proximity to Zn-emitting industries and residential topsoil Zn levels through interpolation methods. We constructed a polygenic score of genetic variability based on 81 single nucleotide polymorphisms in genes involved in Zn metabolism. Geometric mean ratios of toenail Zn across categories of each determinant were estimated from multivariate linear regression models on log-transformed toenail Zn. RESULTS: Geometric mean toenail Zn was 104.1 µg/g in men and 100.3 µg/g in women. Geometric mean toenail Zn levels were 7 % lower (95 % confidence interval 1-13 %) in men older than 69 years and those in the upper tertile of fibre intake, and 9 % higher (3-16 %) in smoking men. Women residing within 3 km from Zn-emitting industries had 4 % higher geometric mean toenail Zn levels (0-9 %). Dietary Zn intake and polygenic score were unrelated to toenail Zn. Overall, the available determinants only explained 9.3 % of toenail Zn variability in men and 4.8 % in women. DISCUSSION: Sociodemographic factors, lifestyle, diet, and environmental exposure explained little of the individual variability of toenail Zn in the study population. The available genetic variants related to Zn metabolism were not associated with toenail Zn.


Assuntos
Unhas , Zinco , Biomarcadores/análise , Exposição Ambiental/análise , Feminino , Humanos , Masculino , Unhas/química , Compostos Orgânicos/análise , Solo , Espanha , Zinco/análise
17.
Medicine (Baltimore) ; 101(26): e29744, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35777009

RESUMO

The aim of this cross-sectional study was to investigate the association between lower limb strength, muscle mass and composition, and balance ability in elders. Thirthy-four older participants (Age: 65.6 ± 4.73 years; male = 10 and female = 24) were assessed for muscle strength (maximal isometric strength of knee extensors and one repetition maximum by leg press, the one repetition maximum [1RM]), balance and gait capacity (Mini-BESTest), body composition by whole-body dual energy x-ray absorptiometry (obtaining Appendicular Skeletal Muscle Mass Index, ASMMI), and magnetic resonance imaging of thigh to evaluate Intermuscular Adipose Tissue (IMAT) and muscle Cross Sectional Area (CSA). Positive correlations between 1RM and ASMMI (rs = 0.64, P < .0001) and thigh CSA (rs = 0.52, P = .0017), but not with thigh IMAT, were found. In addition, significant correlations between knee extensors strength and ASMMI (rs = 0.48, P = .004) and thigh CSA (rs = 0.49, P = .0033) and IMAT (rs = -0.35, P = .043) were observed, whereas no significant correlations between the Mini-BESTest with ASMMI, thigh CSA, and IMAT were observed. Lower limb strength positively correlated with appendicular muscle mass. Further, the maximal isometric strength of knee extensors negatively correlated with thigh IMAT in elderly patients, whereas the dynamic balance ability did not correlate with any of the morphological variables of the muscle (i.e., ASMMI, CSA, and IMAT). A reduced muscle size and strength could affect movement and reduce physical function in older patients. Improving the composition and size of muscle in elder subjects could reduce frailty and risk of falls.


Assuntos
Força Muscular , Coxa da Perna , Tecido Adiposo/diagnóstico por imagem , Idoso , Composição Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia
18.
J Sci Med Sport ; 25(8): 678-683, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35644757

RESUMO

OBJECTIVES: To validate the application of Corrective Adjustment Procedures for removing Relative Age Effects in youth athletic contexts, this study estimated the longitudinal relationships between decimal age (chronological and relative) and performance in male and female long jumpers. Using trendlines, Corrective Adjustment Procedures were applied, and Relative Age Effect distributions associated with performance attainment were re-examined. DESIGN: Retrospective longitudinal design examining competitive long-jump data between 2005 and 2019. METHODS: In Part I, participants were 689 junior Italian long jumpers (age range = 11.01-17.99 years; 56.6% females) who participated in ≥three events. Longitudinal modelling and regression equations quantified the sex-specific relationships between decimal age and long jump performance. In Part II, equations were utilised to adjust individual performance within an independent sample (N = 13,639; 50.1% females) of age-matched jumpers. Relative Age Effect distributions within attainment levels (i.e., Top 25-10%) were examined based on raw and correctively adjusted performance. RESULTS: Irrespective of sex, Relative Age Effects were prevalent across all age-groups with medium-large effect sizes at 12-17 (males and females) and 12-17 years (females) of age (Cramer's V range = 0.07-0.28). Relative Age Effect bias magnitude also increased with attainment level (i.e., Top 25-10%). Following Corrective Adjustment Procedure application, typical Relative Age Effects were removed with non-significant deviations in relative age distributions regardless of sex or age-group or attainment level (Top 25 or 10%). CONCLUSIONS: Findings provide efficacy for Corrective Adjustment Procedure application to remove Relative Age Effects across youth long jumping events. Corrective Adjustment Procedures suggest potential in improving performance evaluation, identification of technically skilled performers, and sporting experiences.


Assuntos
Desempenho Atlético , Adolescente , Distribuição por Idade , Fatores Etários , Atletas , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos
19.
Artigo em Inglês | MEDLINE | ID: mdl-35457555

RESUMO

BACKGROUND: The coronavirus (COVID-19) pandemic led governments to adopt strict containment measures to avoid spreading the virus. These essential measures led to home confinement that influenced both the physical and mental health of populations. Physical activity plays a key role in preventing chronic diseases and promoting protective psychological factors. In the context of a lockdown, understanding the motives that guide people to enact physical activity is an important issue for public health. The present study aimed to evaluate the relation between autonomous motivation and physical activity, considering the role of behavioral intention and anxiety in a longitudinal moderated mediation model. METHODS: Italian participants (N = 86; meanage = 29.74, standard deviation = 9.74; female = 53.5%) completed a booklet composed of different questionnaires (motivation, intention, anxiety, and physical activity) 3 weeks apart. RESULTS: The hypothesized model is supported by the evidence; both autonomous motivation and intention are direct predictors of physical activity. The results also show that the direct effect of autonomous motivation on physical activity is stronger in participants with low anxiety, while high levels of anxiety are a significant moderator of the intention-behavior relation. CONCLUSIONS: In conclusion, a multidisciplinary approach should be promoting methods and infrastructures to permit people to adhere to physical activity, as a front line against any health emergency.


Assuntos
COVID-19 , Adulto , Ansiedade/epidemiologia , Ansiedade/psicologia , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Depressão/psicologia , Exercício Físico , Feminino , Humanos , Intenção , Estudos Longitudinais , Motivação , SARS-CoV-2
20.
Artigo em Inglês | MEDLINE | ID: mdl-35409934

RESUMO

Despite the common belief that sleep quality at altitude is poor, the scientific evidence to support this notion is still modest. Therefore, the purpose of the present study was to evaluate possible changes of actigraphy-based and subjective sleep parameters in a group of elite open-water swimmers during a 14-day altitude training camp (ATC) at 1500 m. The study subjects were five Olympic-level open-water swimmers (mean age: 25.0 ± 3.2 years; 3 females and 2 males). All subjects wore a wrist activity monitor and filled a sleep diary for 18 consecutive nights, 4 nights before and 14 nights during ATC. The data were then analyzed at four different time points: before ATC (PRE), the first two days of ATC (T1), and after one (T2) and two weeks of ATC (T3). Training load, assessed as the covered distance (km), session rating of perceived exertion (sRPE), and heart rate (HR), was monitored during the week before and the first and second week of ATC. No significant differences in objective and subjective scores of sleep quality were detected, whereas the sleep onset time (p = 0.018; η2p = 0.83, large) and sleep offset time (p < 0.001; η2p = 0.95, large) significantly differed among PRE, T1, T2, and T3: elite athletes started to sleep and woke up ≃ 1 h earlier the first two days of ATC compared to PRE (sleep onset time: p = 0.049; sleep offset time: p = 0.016). Further, an increase in the training volume during the two weeks of the ATC was observed, with the most time spent in a low-intensity regime and an increase in time spent in a high-intensity regime compared to PRE. Sleep quality was not negatively influenced by a 14-day altitude training camp at 1500 m in a group of Olympic-level elite swimmers despite an increase in perceived exertion during training sessions. Nonetheless, early sleep onset and sleep offset times were observed for the first two nights of ATC: elite athletes started to sleep and woke up ≃ 1 h earlier compared to the baseline nights.


Assuntos
Altitude , Água , Adulto , Atletas , Feminino , Humanos , Masculino , Sono/fisiologia , Natação/fisiologia , Adulto Jovem
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