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1.
Sci Total Environ ; 954: 176532, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39343394

RESUMO

The primary driver of increasing atmospheric concentrations of nitrous oxide (N2O) is the use of organic and synthetic fertilizer to increase agricultural crop production. Current global estimates are based on IPCC N2O emission factor (EF) calculations, although there are shortcomings as many of the N2O EFs are derived from measurements during the cropping season. These neglect the fallow season, and do not adequately account for double or even triple cropping systems or legacy effects on soil N2O emissions in the following year. In this study, we assessed the legacy effect of fertilization on soil N2O fluxes using data from a long-term double-cropping field experiment with summer maize and winter wheat in rotation, in which no nitrogen (N; NN) and balanced manure with synthetic N (MN) fertilized treatments were switched to allow an assessment of legacy effects. Based on high-frequency measurements of N2O and previous data, we calculated that the historical N fertilization, or legacy effect, explained 23 % of the annual flux of 0.81 kg N ha-1 yr-1 in the first season of observation. In the following three seasons, the legacy effect of the previous N fertilization regime decreased to a negligible level, with N2O emissions mainly driven by in-season fertilization. Our data show that, on average, the seasonal EF for N2O was about 0.11 % higher in response to the previous N fertilization. Our study indicates that the current N2O EF may severely underestimate emissions because studies ignore legacy effects on N2O emissions from zero N plots and only compare zero N with N fertilization treatments for a given season or year to derive seasonal or annual N2O EF.

2.
Clin Sports Med ; 43(4): 585-599, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39232568

RESUMO

In-season management of anterior shoulder instability in athletes is a complex problem. Athletes often wish to play through their current season, though recurrent instability rates are high, particularly in contact sports. Athletes are generally considered safe to return to play when they are relatively pain-free, and their strength and range of motion match the uninjured extremity. If an athlete is unable to progress toward recovering strength and range of motion, surgical management is an option, though this is often a season-ending decision.


Assuntos
Traumatismos em Atletas , Instabilidade Articular , Volta ao Esporte , Humanos , Instabilidade Articular/cirurgia , Instabilidade Articular/fisiopatologia , Instabilidade Articular/diagnóstico , Traumatismos em Atletas/cirurgia , Traumatismos em Atletas/diagnóstico , Articulação do Ombro/fisiopatologia , Articulação do Ombro/cirurgia , Luxação do Ombro/cirurgia , Luxação do Ombro/diagnóstico , Luxação do Ombro/fisiopatologia , Lesões do Ombro , Amplitude de Movimento Articular , Tomada de Decisões , Atletas
3.
Artigo em Inglês | MEDLINE | ID: mdl-39094761

RESUMO

Management of the in-season athlete presenting with an anterior shoulder dislocation is a nuanced process that continues to be refined. Options and pathways between nonoperative and operative treatment have undergone many iterations over a century of orthopedic research and advancement. It requires an understanding of sport-specific demands and the individual athlete's goals. The orthopedic surgeon must have mastery of the natural history, treatment options, and outcomes of anterior shoulder dislocations. Balance of these factors is delicate and highly individualized for each athlete; and is why management of the in-season athlete with an anterior shoulder dislocation remains an art for the orthopedic surgeon.

4.
J Environ Manage ; 351: 119615, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38091728

RESUMO

High-resolution mapping of rice fields is crucial for understanding and managing rice cultivation in countries like Bangladesh, particularly in the face of climate change. Rice is a vital crop, cultivated in small scale farms that contributes significantly to the economy and food security in Bangladesh. Accurate mapping can facilitate improved rice production, the development of sustainable agricultural management policies, and formulation of strategies for adapting to climatic risks. To address the need for timely and accurate rice mapping, we developed a framework specifically designed for the diverse environmental conditions in Bangladesh. We utilized Sentinel-1 and Sentinel-2 time-series data to identify transplantation and peak seasons and employed the multi-Otsu automatic thresholding approach to map rice during the peak season (April-May). We also compared the performance of a random forest (RF) classifier with the multi-Otsu approach using two different data combinations: D1, which utilizes data from the transplantation and peak seasons (D1 RF) and D2, which utilizes data from the transplantation to the harvest seasons (D2 RF). Our results demonstrated that the multi-Otsu approach achieved an overall classification accuracy (OCA) ranging from 61.18% to 94.43% across all crop zones. The D2 RF showed the highest mean OCA (92.15%) among the fourteen crop zones, followed by D1 RF (89.47%) and multi-Otsu (85.27%). Although the multi-Otsu approach had relatively lower OCA, it proved effective in accurately mapping rice areas prior to harvest, eliminating the need for training samples that can be challenging to obtain during the growing season. In-season rice area maps generated through this framework are crucial for timely decision-making regarding adaptive management in response to climatic stresses and forecasting area-wide productivity. The scalability of our framework across space and time makes it particularly suitable for addressing field data scarcity challenges in countries like Bangladesh and offers the potential for future operationalization.


Assuntos
Oryza , Estações do Ano , Bangladesh , Ferramenta de Busca , Agricultura/métodos
5.
Curr Rev Musculoskelet Med ; 16(7): 295-305, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37195384

RESUMO

PURPOSE OF REVIEW: Anterior glenohumeral instability is a common injury in contact and collision athletes, and in-season management remains a controversial topic. RECENT FINDINGS: Several recent studies have examined non-operative and operative management of in-season athletes after instability events. Non-operative treatment is associated with faster return to play and higher rates of recurrent instability. Dislocations and subluxations have similar rates of recurrent instability but non-operatively treated subluxations have a quicker return to play than dislocations. Operative treatment is often a season ending decision but is associated with high rates of return to sport and significantly lower rates of recurrent instability. Indications for in-season operative intervention may include critical glenoid bone loss (>15%), an off-track Hill-Sachs lesion, an acutely reparable bony Bankart lesion, high-risk soft tissue injures such as a humeral avulsion of the glenohumeral ligament or displaced anterior labral periosteal sleeve avulsion, recurrent instability, insufficient time remaining in season to rehabilitate from injury, and inability to successfully return to sport with rehabilitation. It is the role of the team physician to appropriately educate athletes on risks and benefits of operative and non-operative treatment strategies and guide athletes through the shared decision-making process that balances these risks against their long-term health and athletic career goals.

6.
Biology (Basel) ; 12(1)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36671812

RESUMO

There is evidence for the effectiveness of youth combined plyometric and sprint with change of direction (COD) training. However, the evidence is not well-known regarding the in-season effects of biological age (peak height velocity­PHV) on the motor adaptive processes following combined plyometric and COD with ball training (P-CODBT) in youth soccer players. This study aimed to examine the in-season effects of P-CODBT (8 weeks and twice a week) on the athletic performances of male youth soccer players, circa- and post-PHV. In a randomized controlled training study with pre-to-post measurements, forty-eight male players were assigned into two experimental (performing P-CODBT; n = 12 × circa-PHV and n = 12 × post-PHV) and two control groups (CONG; n = 12 × circa-PHV and n = 12 × post-PHV). The pre- and post-training participants were assessed for their anthropometric, linear sprinting with and without a ball, COD speed with and without a ball, vertical jump, dynamic balance, and endurance-intensive performances. After the intervention, the experimental condition induced significant (all p < 0.0001) and small to large effect size (ES = 0.263−3.471) additional gains only on explosive measures compared to CONG. Both the experimental (all p < 0.0001; ES = 0.338−1.908) and control (p = 0.011−0.0001; ES = 0.2−1.8) groups improved their athletic performances over the training period. The improvements generated by p-CODBT were not affected by biological age. In-season short-term P-CODBT (twice a week) could be safe way to generate benefits in explosive performances in youth soccer players, which are relevant components of match-winning actions in soccer.

7.
Sports Health ; 15(1): 105-110, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35081842

RESUMO

CONTEXT: In-season glenohumeral instability is a common clinical dilemma faced by physicians who care for athletes. Both nonoperative and operative management of athletes with in-season glenohumeral instability have been well described. Functional bracing remains less understood as a treatment modality. This review aims to provide an update on the most recent literature regarding the use of functional bracing for shoulder instability. EVIDENCE ACQUISITION: MEDLINE (PubMed and Ovid platforms), Web of Science, Embase, and Cochrane Database of Systemic Reviews were searched for articles available in English through June 1, 2021. The search terms shoulder brace, shoulder instability, athlete, in-season, glenohumeral instability, anterior shoulder instability, posterior shoulder instability, and bracing were used. STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 3. RESULTS: Research on the clinical outcomes of functional bracing remains mixed for patients with shoulder instability. Two studies have demonstrated improved return to play with functional bracing, while 1 study demonstrated no difference in return to play between braced athletes and nonbraced athletes with anterior instability. One previous study demonstrated that prophylactic use of bilateral shoulder stabilizing braces significantly decreased time lost due to injury in athletes with posterior instability. Previous biomechanical studies have demonstrated improved proprioception with brace wear as well as successful limitation of active shoulder range of motion. CONCLUSION: Bracing in athletes with shoulder instability remains an important nonoperative treatment modality. While clinical benefits are yet to be validated through high-quality studies, preliminary results suggest a potential benefit to recovery, with minimal downsides. Nevertheless, the use of bracing remains an individual choice but is especially recommended in settings of high-risk sports for shoulder instability, such as football.


Assuntos
Futebol Americano , Instabilidade Articular , Luxação do Ombro , Lesões do Ombro , Articulação do Ombro , Humanos , Luxação do Ombro/cirurgia , Instabilidade Articular/cirurgia , Ombro , Estações do Ano , Lesões do Ombro/terapia , Atletas , Volta ao Esporte , Recidiva
8.
Int J Sports Physiol Perform ; 18(3): 231-239, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36460003

RESUMO

PURPOSE: To compare the effects of variable-resistance complex training (VRCT) versus traditional complex training (TCT) on muscle architecture in rugby league players during a 6-week mesocycle. METHODS: Twenty-four rugby league players competing in the British University & Colleges Sport (BUCS) Premier North Division were randomized to VRCT (n = 8), TCT (n = 8), or control (n = 8). Experimental groups completed a 6-week lower-body complex training intervention (2×/wk), which involved alternating high-load resistance exercise with plyometric exercise in the same session. The VRCT group performed resistance exercises at 70% of 1-repetition maximum (1RM) + 0% to 23% of 1RM from band resistance with a 90-second intracontrast rest interval, whereas the TCT group performed resistance exercise at 93% of 1RM with a 4-minute intracontrast rest interval. Muscle thickness (MT), pennation angle, and fascicle length (Lf) were assessed for the vastus lateralis (VL) and gastrocnemius medialis using ultrasound imaging. RESULTS: Both TCT and VRCT groups significantly improved VL MT and VL Lf compared with control (all P < .05). Standardized within-group changes in MT and Lf (Cohen dav ± 95% CI) were moderate for TCT (dav = 0.91 ± 1.0; dav = 1.1 ± 1.1) and unclear for VRCT (dav = 0.44 ± 0.99; dav = 0.47 ± 0.99), respectively. Differences in change scores between TCT and VRCT were unclear. CONCLUSIONS: VRCT and TCT can be utilized during the competitive season to induce favorable MT and Lf muscle architecture adaptations for the VL. TCT may induce greater muscle architecture adaptations of the VL, whereas VRCT may be of more practical value given the shorter intracontrast rest interval between resistance and plyometric exercises.


Assuntos
Futebol Americano , Treinamento Resistido , Humanos , Rugby , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Músculo Quadríceps/fisiologia , Treinamento Resistido/métodos , Futebol Americano/fisiologia
9.
Plants (Basel) ; 11(13)2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35807735

RESUMO

Field studies conducted over time to collect any type of plant response to a set of treatments are often not treated as repeated measures data. The most used approaches for statistical analyses of this type of longitudinal data are based on separate analyses such as ANOVA, regression, or time contrasts. In many instances, during the review of manuscripts, reviewers have asked researchers to treat year, for example, as a random effect and ignore the interactions between year and other main effects. One drawback of this approach is that the correlation between measurements taken on the same subject over time is ignored. Here, we show that avoiding the covariance between measurements can induce erroneous (e.g., no differences reported when they exist, or differences reported when they actually do not exist) inference of treatment effects. Another issue that has received little attention for statistical inference of multi-year field experiments is the combination of fixed, random, and repeated measurement effects in the same statistical model. This type of analysis requires a more in-depth understanding of modeling error terms and how the statistical software used translates the statistical language of the given command into mathematical computations. Ignoring possible significant interactions among repeated, fixed, and random effects might lead to an erroneous interpretation of the data set. In this manuscript, we use data from two field experiments that were repeated during two and three consecutive years on the same plots to illustrate different modeling strategies and graphical tools with an emphasis on the use of mixed modeling techniques with repeated measures.

10.
Phys Sportsmed ; 50(1): 54-59, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33337278

RESUMO

OBJECTIVES: Wrestling is a physically demanding sport with an inherently high risk of injury relative to other sports. Injury risk factors may change dramatically for athletes participating in off-season wrestling, given exposure to new opponents, training methods, and wrestling styles compared with in-season months; however, this has never been elucidated in the literature. This study seeks to characterize the injuries sustained while participating in off-season wrestling and compare them to injuries sustained during the in-season months for middle and high school age athletes. METHODS: The National Electronic Injury Surveillance System (NEISS) database was queried (2000-2018) to directly compare national estimates and injury characteristics of middle and high school age patients (11-18 years of age) presenting to US emergency departments (EDs) with wrestling-associated injuries, stratified by in-season and off-season months. RESULTS: The average annual number of patients 11 to 18 years of age presenting to US EDs with wrestling-associated injuries was 20,157 (95% Confidence Interval [C.I.] 16,622-23,691) during in-season months and 5,321 (C.I. 3,954-6,688) during off-season months between 2000 and 2018. Those sustaining in-season injuries were significantly (p < 0.001) more and less likely to injure their upper trunk (8.0%; C.I. 7.1% - 8.8%) and wrists (3.7%; C.I. 3.2% - 4.2%), respectively, than those presenting with off-season injuries (upper trunk: 5.3%; C.I. 4.2% - 6.5%; wrists: 6.6%; C.I. 5.1% - 8.1%). There were no significant differences with respect to the overall prevalence of injury diagnoses between in-season and off-season patient cohorts, including for fractures and dislocations (p > 0.05). CONCLUSION: These findings may alleviate concerns that off-season wrestling is inherently more dangerous than in-season wrestling due to changes in wrestling styles or opponent skill levels as the prevalence of specific injury diagnoses between the two seasons is similar.


Assuntos
Traumatismos em Atletas , Luta Romana , Adolescente , Traumatismos em Atletas/epidemiologia , Criança , Serviço Hospitalar de Emergência , Humanos , Incidência , Estações do Ano , Estados Unidos/epidemiologia , Luta Romana/lesões
11.
J Environ Manage ; 304: 114264, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34906809

RESUMO

Enhanced efficiency fertilisers (EEF) may reduce nitrogen (N) losses and improve uptake efficiency through synchronising N release with in-season plant requirements. We hypothesised that EEF formed via matrix encapsulation in biodegradable polymers will improve N use efficiency when compared to conventional urea fertiliser. This hypothesis was investigated for two biodegradable polymer matrices: polyhydroxyalkanoate (PHA), containing 11.6% urea (by mass), and polybutylene-adipate-co-terephthalate (PBAT), containing either 19.4 or 32.7% urea; and two contrasting soil types: sand and clay. Nitrogen availability and form was investigated under leaching conditions (water) with a growth accelerator pot experiment involving a horticultural crop and novel non-destructive three-dimensional scanning to measure in-season biomass development. The PBAT 32.7% formulation enabled greater above ground biomass production at both 50 and 100 kg N ha-1 equivalent application rates compared to conventional urea. For the sandy soil, plant scanning indicated that improved uptake performance with PBAT 32.7% was probably the result of greater N availability after 25 days than for conventional urea. Two of the encapsulated formulations (PHA and PBAT 19.4%) tended to decrease nitrogen leaching losses relative to urea (P < 0.05 for the red clay soil). However, decreased N leaching loss was accompanied by poorer N uptake performance, indicative of N being less available in these biopolymer formulations. A snapshot of nitrous oxide emissions collected during peak nitrate concentration (prior to planting and leaching) suggested that the biopolymers promoted N loss via gaseous emission relative to urea in the sandy soil (P < 0.05), and carbon dioxide emissions data suggested that biopolymer-carbon increased microbial activity (P < 0.1). Controlled testing of N release in water was a poor predictor of biomass production and leaching losses. The diverse behaviours of the tested formulations present the potential to optimise biopolymers and their N loadings by taking into account soil and environmental factors that influence the efficient delivery of N to target crops. The greater N uptake efficiency demonstrated for the PBAT 32.7% formulation confirms our hypothesis that matrix encapsulation can enable better synchronisation of N release with crop requirements and decrease leaching losses.


Assuntos
Fertilizantes , Objetivos , Agricultura , Produtos Agrícolas , Fertilizantes/análise , Nitrogênio/análise , Polímeros , Solo
12.
BMC Sports Sci Med Rehabil ; 13(1): 126, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34641968

RESUMO

BACKGROUND: The interpretation of the load variations across a period seems important to control the weekly progression or variation of the load, or to identify within- micro and mesocycle variations. Thus, the aim of this study was to describe the in-season variations of training monotony, training strain, and acute: chronic workload ratio (ACWR) through session rating of perceived exertion (s-RPE), total distance and high-speed running (HSR) according to playing positions in an elite soccer team. METHODS: Seventeen professional players from an European First League team participated in this study. They were divided four central defenders (CD), three wide defenders (WD), four central midfielders (CM), three wide midfielders (WM) and three strikers (ST). The players were monitored daily over a 41-week period of competition where 52 matches occurred during the 2015-2016 in-season. Through the collection of s-RPE, total distance and HSR, training monotony, training strain and ACWR were calculated for each measure, respectively. Data were analysed across ten mesocycles (M: 1-10). RESULTS: The main results showed significant differences (p < 0.05) for TMs-RPE between CD vs. ST (moderate effect) in M2; between CD vs. CM (moderate effect) for TS of s-RPE; between CD vs. ST moderate effect) in M6 for ACWR of s-RPE. In addition, there was significant difference between CM vs. ST (moderate effect) in M2 for TS of TD; between WD vs. ST (moderate effect) in M3 for ACWR of TD. Moreover, there were significant differences for TM of HSR between CD vs. WD (very large effect); CD vs. WD (moderate effect) in M4 for TS of HSR. CONCLUSIONS: The present study presents new insights to coaches and technical staff about the variation profiling of TM, TS, and ACWR calculated with internal and external load measures, between player positions during 10 mesocycles.

13.
Orthop J Sports Med ; 9(9): 23259671211032239, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34541015

RESUMO

BACKGROUND: Many in-season athletes choose to delay or avoid surgery in order to continue playing and avoid downtime such as missed games or seasons. PURPOSE: To learn about the attitudes toward the injury and treatment of in-season shoulder instability in competitive athletes who have suffered a shoulder dislocation. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A study-specific questionnaire about athletes' perceptions of injury and treatment was administered to injured players. Secondary outcomes included the American Shoulder and Elbow Surgeons (ASES) score and the Western Ontario Shoulder Instability Index (WOSI). Mean scores and standard deviations were calculated, and between-group analyses with t tests were performed to compare the ASES and WOSI scores. The Mann-Whitney U test was used for analyses performed on the following groups: early operative versus nonoperative management; age <18 versus ≥18 years; first-time dislocators versus recurrent dislocators; self-reducing subluxations versus dislocations requiring assistance; and dominant arm affected versus nondominant arm. RESULTS: There were 45 patients included in this study (33 male, 12 female) with a mean age of 18 ± 2.8 years. Several sports were represented, with the most common being football, baseball, soccer, and rugby. In this study of in-season athletes with shoulder instability, 13 (28.9%) chose early surgery, 4 (8.9%) chose surgery at season's end, while 28 (62.2%) chose physical therapy followed by a wait-and-see approach, with 13 (46.4%) of these patients ultimately requiring surgery. Athletes who chose nonoperative treatment were statistically more likely to believe that their shoulder would heal on its own (P < .001) or with physical therapy (P < .025); they were also more likely to agree that they would rather stop sports than undergo surgery (P < .04). Athletes with worse ASES and WOSI scores at injury were more likely to choose surgery (P < .03 and P < .05, respectively). Athletes with >1 dislocation were less likely to believe that the shoulder would heal without surgery (P < .025). Most athletes agreed that seasonal timing and recruitment prospects were an important factor in their decision in favor of surgery (P < .038), and most agreed that their doctor influenced their ultimate treatment decision (P < .006). Most athletes also agreed that a repeat dislocation would cause further injury to the shoulder. CONCLUSION: Treatment decisions were most strongly related to the athletes' perceptions of injury severity and the influence of the treating surgeon.

14.
Medicina (Kaunas) ; 57(7)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201642

RESUMO

Background and Objectives: Interpretation of the load variations across a period seems important to control the weekly progression or variation of the load, or to identify in-micro- and mesocycle variations. Thus, the aims of this study were twofold: (a) to describe the in-season variations of training monotony, training strain and acute:chronic workload ratio (ACWR) through session ratings of perceived exertion (s-RPE), total distance and high-speed running (HSR); and (b) to compare those variations between starters and non-starters. Materials and Methods: Seventeen professional players from a European First League team participated in this study. They were divided in two groups: starters (n = 9) and non-starters (n = 8). The players were monitored daily over a 41-week period of competition where 52 matches occurred during the 2015-2016 in-season. Through the collection of s-RPE, total distance and HSR, training monotony, training strain and ACWR were calculated for each measure, respectively. Data were analyzed across ten mesocycles (M: 1 to 10). Repeated measures ANOVA was used with the Bonferroni post hoc test to compare M and player status. Results: The results revealed no differences between starters vs. non-starters (p > 0.05). M6 had a greater number of matches and displayed higher values for monotony (s-RPE, total distance and HSR), strain (only for total distance) and ACWR (s-RPE, TD and HSR). However, the variation patterns for all indexes displayed some differences. Conclusions: The values of both starters and non-starters showed small differences, thus suggesting that the adjustments of training workloads that had been applied over the season helped to reduce differences according to the player status. Even so, there were some variations over the season (microcycles and mesocycles) for the whole team. This study could be used as a reference for future coaches, staff and scientists.


Assuntos
Médicos , Corrida , Futebol , Humanos , Estações do Ano , Carga de Trabalho
15.
Int J Sports Physiol Perform ; 16(9): 1288-1294, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33662927

RESUMO

PURPOSE: (1) To compare the sleep of female players from a professional soccer team to nonathlete controls across an in-season week and (2) to compare the sleep of core and fringe players from the same team on the night after a match to training nights. METHODS: Using an observational design, 18 professional female soccer players and 18 female nonathlete controls were monitored for their sleep via wristwatch actigraphy across 1 week. Independent-sample t tests and Mann-Whitney U tests were performed to compare sleep between groups, while an analysis of variance compared sleep on training nights to the night after a match. RESULTS: Soccer players had significantly greater sleep duration than nonathlete controls (+38 min; P = .009; d: 0.92), which may have resulted from an earlier bedtime (-00:31 h:min; P = .047; d: 0.70). The soccer players also had less intraindividual variation in bedtime than nonathletes (-00:08 h:min; P = .023; r: .38). Despite this, sleep-onset latency was significantly longer among soccer players (+8 min; P = .032; d: 0.78). On the night after a match, sleep duration of core players was significantly lower than on training nights (-49 min; P = .010; d: 0.77). In fringe players, there was no significant difference between nights for any sleep characteristic. CONCLUSIONS: During the in-season period, sleep duration of professional female soccer players is greater than nonathlete controls. However, the night after a match challenges the sleep of players with more match involvement and warrants priority of sleep hygiene strategies.


Assuntos
Futebol , Actigrafia , Feminino , Humanos , Estações do Ano , Sono , Higiene do Sono
16.
Artigo em Inglês | MEDLINE | ID: mdl-33138002

RESUMO

The purpose of this study was to test the relationships between training workload (WL) parameters with variations in anaerobic power and change of direction (COD) in under-16 soccer players. Twenty-three elite players under 16 years were daily monitored for their WL across 20 weeks during the competition soccer season. Additionally, players were assessed three times for anthropometric, body composition, COD, and anaerobic power. A correlational analysis between the mean differences between assessments and accumulated WL parameters were conducted. Moreover, a regression analysis was executed to explain the variations in the percentage of change in fitness levels considering the accumulated WL parameters and peak height velocity. The accumulated daily loads during one week showed a large and a moderate correlation with peak power and COD at different periods of the season. Regression analysis showed no significant predictions for COD (F(12, 10) = 1.2, p = 0.41) prediction, acute load (F(12, 10) = 0.63, p = 0.78), or chronic load (F(12, 10) = 0.59, p = 0.81). In conclusion, it may be assumed that the values of the chronic workload and the accumulated training monotony can be used to better explain the physical capacities of young soccer players, suggesting the importance of psychophysiological instruments to identify the effects of the training process in this population.


Assuntos
Esforço Físico , Futebol , Carga de Trabalho , Aceleração , Adolescente , Composição Corporal , Teste de Esforço , Humanos , Irã (Geográfico)
17.
Artigo em Inglês | MEDLINE | ID: mdl-32916804

RESUMO

The purpose of this study was two-fold: (1) to describe weekly average values for training monotony (TM) and training strain (TS) and their variations across the full soccer season, based on the number of accelerations and decelerations; (2) to analyze the differences between starter and non-starter players on weekly average TM and TS values for the pre-season and three in-season periods. In total, 21 professional soccer players were evaluated over 48 weeks during the full-season. The TM and TS were calculated based on the number of accelerations and decelerations at zone 1, zone 2 and zone 3, respectively. The results revealed that starters presented higher values compared to non-starters throughout the full season for all variables analyzed (all, p < 0.05). Generally, there were higher values in the pre-season. Specifically, accelerations at zones 1, 2 and 3 revealed moderate to very large significance of the starters compared to non-starters over the full-season. Decelerations at zone 1, 2 and 3 presented moderate to nearly optimally significant greater weekly averages for starters compared to non-starters during the full season. In conclusion, the TM and TS values were higher for starters compared to non-starters through the full-season, which confirms that the training session does not provide a sufficient load to non-starter soccer players during the full-season.


Assuntos
Acelerometria , Futebol , Aceleração , Humanos , Condicionamento Físico Humano , Estações do Ano , Futebol/fisiologia
18.
J Sports Sci ; 38(19): 2225-2235, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32921247

RESUMO

Despite evidence supporting the positive affect sleep has on sport performance, there is limited application of sleep research in cricket. This study investigated the sleep behaviours of 26 elite South African cricket players (28.6 ± 4.0 years) during home and away competition. Players completed an altered version of the Core Consensus Sleep Diary every morning post-travel, pre-match and post-match. Linear mixed model regression was used to compare differences in sleep between time-periods, venues and formats. Spearman's correlations (rs) assessed the relationship of match performance and sleep. Post-match total sleep time (06:31 ± 01:09) was significantly (p < 0.05) shorter compared to post-travel (07:53 ± 01:07; g = 1.19) and pre-match (08:43 ± 01:03; g = 1.98). Post-travel sleep onset latency and sleep efficiency were significantly shorter (-20; g = 1.35) and higher (+10.4%; g = 0.74) at home than away respectively. Longer sleep onset latencies and shorter total sleep times were significantly associated with poorer One-Day International (rs = -0.57) and Test (rs = 0.59) batting performances respectively. The poor post-match sleep behaviour, and the sleep and performance correlations, provide motive for future interventions to focus on recovery and the use of sleep monitoring as a competitive advantage.


Assuntos
Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Críquete/fisiologia , Sono , Adulto , Humanos , Estudos Longitudinais , Masculino , Privação do Sono , Fatores de Tempo
19.
Int J Sports Physiol Perform ; 15(7): 1019-1025, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32534447

RESUMO

PURPOSE: To determine the effect of in-season differential training on volleyball spike-jump technique and performance in elite-level female players. METHODS: During the season, spike jumps of 12 elite female players (Austrian Volleyball League Women) were recorded by 13 Qualisys Oqus cameras (250 Hz) and an AMTI force plate (1000 Hz). First measurement was made at the beginning of the investigation. Two identical measurements were repeated after a first and a second interval. The first interval served as control phase. The second interval was comparable in length and regular program but included differential training (6 wk, 8 sessions of 15-20 min) as a modified warm-up. It addressed specific performance determinants. Analyses of variances were calculated for the 3 measurements and for the development during control and intervention phase. RESULTS: Initial jump height (0.44 [0.09] m) changed by -4.5% during the control phase and +11.9% during the intervention (P < .001, ηp2=.70). All approach variables, arm backswing, and velocity-conversion strategy improved compared with the control phase (Δ%: 6.1-51.2%, P < .05, ηp2=.40-.80). Joint angles, countermovement depth, maximal angular velocities, and torso incline were not affected (Δ%: -2.9-9.1%, P = .066-.969, ηp2=.00-.27). CONCLUSIONS: In-season differential training led to technical adaptations and increased spike-jump height in elite female players. The differential training program allowed players to experience a range of adaptability and to adjust toward an individual optimum in technical components of performance determinants. Coaches are encouraged to apply technical differential training to elite athletes and to target biomechanical performance factors specifically.

20.
Plant Dis ; 104(6): 1685-1693, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32357121

RESUMO

Bacterial spot caused by Xanthomonas arboricola pv. pruni was first detected on almond in California in 2013, and it is reported herein as a new disease in California based on fulfilling Koch's postulates and identification of the pathogen using species-specific PCR primers. Infected mummified fruit from the previous growing season and their peduncles were identified as primary overwintering sites of the bacterium on the tree. Twig cankers were not observed, and the pathogen was not recovered from dormant buds. Isolation from flowers and emerging leaves was only successful when they were collected within 20 cm of an infected, mummified fruit on the tree. Inoculation of flowers and immature fruit as well as immature and mature leaves resulted in disease development, indicating a long period of host susceptibility in the spring, but disease incidence was highest in fruit inoculations. In split-plot trials over 3 years, dormant applications in December or January with copper or copper-mancozeb significantly reduced the disease compared with untreated controls in seasons with high rainfall, but they had no effect in seasons with low rainfall. In-season applications of copper-mancozeb at petal fall or at full bloom and petal fall were also effective in reducing the disease. Phytotoxicity was observed after repeated applications of copper bactericides, especially in low-rainfall seasons. Dormant and in-season treatments of copper-mancozeb mixtures integrated with removal of mummified fruit are currently the best management strategies for bacterial spot of almond in California.


Assuntos
Prunus dulcis , Xanthomonas , California , Doenças das Plantas
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