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1.
Artigo em Inglês | MEDLINE | ID: mdl-38944372

RESUMO

BACKGROUND: Total shoulder arthroplasty is performed by orthopedic surgeons with various fellowship training backgrounds. Whether surgeons performing shoulder arthroplasty with different types of fellowship training have differing rates of complications and reoperation remains unknown. METHODS: The PearlDiver Mariner database was retrospectively queried from the years 2010-2022. Patients undergoing shoulder arthroplasty were selected using the CPT code 23472. Those undergoing revision arthroplasty and those with a history of fracture, infection, or malignancy were excluded. Fellowship was determined and verified via online search. Only surgeons who performed a minimum of 10 cases were selected; and PearlDiver was queried using their provider ID codes. Primary outcome measures included 90-day, 1-year, and 5-year rates of complication and reoperation. A Bonferroni correction was utilized in which the significance threshold was set at p≤0.00023 RESULTS: In total, 150,385 patients met the inclusion criteria and were included in the study. Analysis of surgical trends revealed that Sports Medicine and Shoulder and Elbow fellowship- trained surgeons are performing an increasing percentage of all shoulder arthroplasty over time, with each cohort exhibiting am 11.3% and 4.2% increase from 2010 to 2022, respectively. The geographic region with the highest proportion of cases performed by Sports Medicine surgeons was the West, while the Northeast has the highest proportion of cases performed by Shoulder and Elbow surgeons. Shoulder and Elbow surgeons operated on patients that were significantly younger and had fewer comorbidities. Both Shoulder and Elbow and Sports Medicine surgeons had lower rates of postoperative complications at 90 days, 1 year and 5 years in comparison to surgeons who completed another type of fellowship or no fellowship. Across each time point, the rates of individual complications between Sports Medicine and Shoulder and Elbow were comparable, but the pooled complication rate was lowest in the Shoulder and Elbow cohort. CONCLUSION: Surgeons who have completed either a Sports Medicine or Shoulder and Elbow fellowship are performing an increasing proportion of shoulder arthroplasty over time. Sports Medicine and Shoulder and Elbow-trained surgeons have significantly lower complication rates at 90 days, 1 year and 5 years postoperatively. The individual complication rates between Sports Medicine and Shoulder and Elbow are comparable, but Shoulder and Elbow has the lowest pooled complication rates overall.

2.
Am J Sports Med ; 51(8): 2176-2185, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37259957

RESUMO

BACKGROUND: Lower extremity (LEX) strains, including hamstring, quadriceps, adductor, and calf strains, are among the most common injuries in sports. These injuries lead to high burden, resulting in significant missed participation time. PURPOSE: To describe the incidence of LEX strains in professional American football. STUDY DESIGN: Descriptive epidemiology study. METHODS: This study included all players who played in ≥1 National Football League (NFL) game or sustained a LEX strain during participation in the 2015-2019 seasons. LEX strain frequency was calculated by setting (game, practice, conditioning), timing in season (offseason, preseason, regular season, postseason), and roster position. Game incidence rates were calculated for season, roster position, and play type. LEX strains were identified in the standardized leaguewide electronic health record (n = 32 teams). RESULTS: Across 5 years, 5780 LEX strains were reported among 2769 players (1-year risk, 26.7%; 95% CI, 26.0%-27.3%); 69% (n = 4015) resulted in time loss. Among all LEX strains, 54.7% were hamstring (n = 3163), 24.1% adductor (n = 1393), 12.6% calf (n = 728), 8.3% quadriceps (n = 477), and 0.3% multiple muscle groups (n = 19). Most were reported during preseason practices (n = 1076; 27%) and regular season games (n = 1060; 26%). The 2-week period of training camp practices comprised 19% of all time-loss strains. Among game injuries, preseason games had the highest rate of LEX strain (2.9/10,000 player-plays; 95% CI, 2.6-3.2). Defensive secondary players accounted for the highest proportion of time-loss LEX strains (27%; n = 1082). In games, punt plays had nearly twice the injury rate of kickoff plays (14.9/1000 plays [95% CI, 13.1-17.0] vs 7.5/1000 plays [95% CI, 6.2-8.9], respectively) and >3 times the rate of pass plays (4.3/1000 plays; 95% CI, 4.0-4.7) and run plays (2.6/1000 plays; 95% CI, 2.3-2.9). In aggregate, LEX strains led to an estimated 16,748 participation days missed each year and a median 12 days missed per injury. CONCLUSION: LEX strains affected 1 in 4 NFL players each year, resulting in a high burden of injury in terms of time lost from practice and competition. Safe return to the NFL season during training camp and reduction of injuries during regular season games are key focuses for future injury reduction.


Assuntos
Futebol Americano , Entorses e Distensões , Humanos , Futebol Americano/lesões , Extremidade Inferior/lesões , Entorses e Distensões/epidemiologia , Músculo Quadríceps/lesões
3.
J Funct Morphol Kinesiol ; 8(1)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36976131

RESUMO

Previous studies have shown that listening to preferred music during resistance and endurance exercises improves performance. However, it is unknown if these phenomena translate to short-duration explosive exercises. The purpose of this study was to investigate the influences of preferred and non-preferred music on countermovement jump (CMJ) performance, isometric mid-thigh pull (IMTP), and psychological responses to music during explosive movements. Physically active females (age 18-25) volunteered to take part in the study. In a counterbalanced, crossover design, participants completed three trials: (1) no music (NM), (2) non-preferred (NP), and (3) preferred (PV) music. Participants completed three maximal IMTP tests on a force-plate-equipped IMTP apparatus with an immovable bar. Attempts lasted 5 s and were separated by 3 min of rest. Furthermore, participants completed three single maximal CMJ attempts separated by 3 min of rest on force plates. All attempts were averaged for analysis. At the commencement of IMTP and CMJ testing, participants were asked to rate how motivated and psyched up they felt during the exercise portion using a visual analog scale. For isometric performance, listening to PM resulted in increased peak force (p = 0.039; d = 0.41) and rate of force development at 200 ms (p = 0.023; d = 0.91) compared with NP. For CMJ, there were no differences between conditions for jump height (p = 0.912; η2 = 0.007) or peak power during the propulsive phase (p = 0.460; η2 = 0.003). Levels of motivation were significantly higher with PM compared with NM (p < 0.001; d = 2.3) and NP (p = 0.001; d = 2.0). Feelings of being psyched up were significantly higher with PM compared with NM (p < 0.001; d = 4.2) and NP (p = 0.001; d = 2.8). Findings suggest that preferred music enhances isometric strength and increases motivation and feelings of being psyched up. Thus, PM may be used as an ergogenic aid during short-duration maximal-effort activities.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36674064

RESUMO

Fluid availability may alter drinking behavior; however, it is currently unknown if the availability of fluid impacts behavior and gastrointestinal issues (GI) that are often associated with increased fluid intake. The purpose of this study was to determine if ad libitum (AL) versus periodic (PER) fluid intake influences fluid consumption and GI distress during exercise in trained athletes. Male and female Division I NCAA Cross Country athletes (n = 11; age = 20 ± 1 years) participated in this counterbalanced crossover study. Each participant completed a moderate intensity 10 km run on two separate occasions. In one trial, participants had unlimited availability to fluid to consume AL. In the other trial, participants consumed PER fluid at stations placed every 3.2 km. Assurance of euhydration prior to each trial was confirmed via urine specific gravity (USG) and urine color. Subjective perceptions of thirst and gastric fullness were assessed pre- and post-exercise via Likert questioning and a visual analog scale, respectively. Participants started each trial euhydrated (AL = 1.009 USG ± 0.009; PER = 1.009 USG ± 0.009; urine color AL, 3 ± 1; urine color PER, 2 ± 1). Fluid volume consumption was significantly higher during the AL condition compared to PER (p = 0.050). Thirst significantly increased from pre- to post-run regardless of treatment (p < 0.001); however, there was no significant difference between the groups (p = 0.492). Feelings of fullness did not change pre-post trial (p = 0.304) or between trials (p = 0.958). Increased fluid availability allows for increased fluid consumption without the negative experience of GI discomfort.


Assuntos
Desidratação , Ingestão de Líquidos , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Estudos Cross-Over , Desidratação/prevenção & controle , Exercício Físico , Sede
5.
Mass Spectrom Rev ; 42(2): 652-673, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34346101

RESUMO

In a world where information-rich methods of analysis are often sought over those with superior figures of merit, there is a constant search for ionization methods which can be applied across diverse analytical systems. The liquid sampling-atmospheric pressure glow discharge (LS-APGD) is a microplasma device which has the inherent capabilities to operate as a combined atomic and molecular (CAM) ionization source. The plasma is sustained by placement of a high voltage (~500 V, dc) onto an electrolytic solution through which the analyte is generally delivered to the discharge. Judicious choice of the solvent provides a means of obtaining atomic/elemental and/or molecular mass spectra. Presented here are the diverse modes of sample introduction and mass spectrometer platforms to which the LS-APGD has been interfaced. Likewise, representative spectra and figures of merit are presented towards elemental and isotope ratio measurements, as well as application to small organic molecules, organometallic complexes, and intact proteins. It is believed that the diversity of analytical applications and ready implementation across the entirety of mass spectrometry platforms portends a level of versatility not realized with other ionization sources.

6.
Can J Urol ; 29(4): 11231-11242, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35969727

RESUMO

INTRODUCTION: Ureteral stent-related symptoms are common after stent placement. Various characteristics of stent design have been previously investigated to mitigate this issue. Our review summarizes available literature on stent design parameters (diameter, material, position, length, distal loop modifications) and their effect on stent-related symptoms, including pain. MATERIALS AND METHODS: We identified articles from PubMed, Medline, EMBASE, Web of Science, and Grey Literature using a search strategy employing MESH search headings (i.e, ureteral stent diameter, length, composition, material, durometer, and stent-related pain). RESULTS: Out of 2,970 identified studies, 26 met eligibility criteria. Most diameter studies found patients with > 6Fr stents reported significantly increased stent-related symptoms. A few did report more migration with thinner stents. Almost half of durometer studies found composition made no difference in symptoms. Distal loop modification studies found minimizing intravesical material decreased stent-related pain. All studies on positioning found patients reported more severe urinary, pain and quality of life symptoms when stents crossed the bladder midline. No difference in stent-related symptoms was seen between multi-length and standard stents patients. CONCLUSION: Adverse symptoms occur commonly after ureteral stent placement. No definitive recommendations on the model stent can be provided due to the heterogeneity of studies. Though the number of robust studies is limited, data suggest stents crossing midline, larger diameters, and those without distal material-reduction modifications may worsen stent-related symptoms. Future studies are needed to better understand the ideal stent design.


Assuntos
Qualidade de Vida , Ureter , Humanos , Dor/etiologia , Dor/prevenção & controle , Stents/efeitos adversos , Bexiga Urinária
7.
Artigo em Inglês | MEDLINE | ID: mdl-35162339

RESUMO

The purpose of this study was to examine the effects of a single acute dose of yohimbine hydrochloride on repeated anaerobic sprint ability. Physically active females (n = 18) completed two separate repeated supramaximal sprint trials each with a different single-dose treatment: placebo (PL; gluten-free corn starch) or yohimbine hydrochloride (YHM; 2.5 mg). For each trial, participants consumed their respective treatment 20 min before exercise. Following a warm-up, participants completed 3 × 15 s Wingate anaerobic tests (WAnTs) separated by 2 min of active recovery. A capillary blood sample was obtained pre- and immediately post-exercise to measure blood concentrations of lactate (LA), epinephrine (EPI), and norepinephrine (NE). Heart rate (HR) and rate of perceived exertion (RPE) were measured following each WAnT. Findings showed that mean power (p < 0.001; η2 = 0.024), total work (p < 0.001; η2 = 0.061), and HR (p < 0.001; η2 = 0.046), were significantly higher with YHM supplementation versus PL. Fatigue index (p < 0.001; η2 = 0.054) and post-exercise LA (p < 0.001; d = 1.26) were significantly lower with YHM compared to PL. YHM resulted in significantly higher EPI concentrations versus PL (p < 0.001; η2 = 0.225) pre- and post-exercise while NE only increased as a function of time (p < 0.001; η2 = 0.227) and was unaffected by treatment. While RPE increased after each WAnT, no differences between treatments were observed (p = 0.539; η2 < 0.001). Together, these results suggest that acute YHM ingestion imparts ergogenic benefits which may be mediated by lower blood LA and fatigue concomitantly occurring with blood EPI increases. Thus, YHM may improve sprint performance although more mechanistic study is warranted to accentuate underlying processes mediating performance enhancement.


Assuntos
Desempenho Atlético , Substâncias para Melhoria do Desempenho , Desempenho Atlético/fisiologia , Suplementos Nutricionais , Método Duplo-Cego , Teste de Esforço , Fadiga , Feminino , Humanos , Substâncias para Melhoria do Desempenho/farmacologia , Ioimbina
8.
Int J Exerc Sci ; 15(7): 79-87, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36896024

RESUMO

The purpose of this study was to investigate the effects of self-selected respite music on upper-body resistance exercise performance. In a crossover, counterbalanced study design, resistance-trained males (n = 10) participated in two bench press trials each with a different condition: 1) No music (NM), 2) Listening to respite music (RM; i.e. during rest periods). Following a warm-up, participants completed 3 sets × repetitions to failure (RTF) at 75% of 1-RM separated by 2 minutes of rest. During the 2-minute rest, participants either listened to NM or RM until the next subsequent set. A linear position transducer was used to measure mean barbell velocity during the first 3 repetitions and averaged for analysis. Rate of perceived exertion (RPE) and motivation were obtained after each set. Results indicate that mean velocity was higher during set 2 (p = 0.009; d = 1.34) and set 3 (p = 0.048; d = 0.95) while listening to RM versus NM. Furthermore, motivation was significantly higher following set 2 (p = 0.005; d = 1.15) and set 3 (p < 0.001; d = 1.79) while listening to RM compared to NM. No changes in RTF or RPE were noted between conditions (p > 0.05). These findings indicate listening to music during recovery may enhance subsequent explosive resistance performance and suggest that listening to music in between bouts of maximal effort could be an effective tool for optimizing performance during competition or training.

9.
J Funct Morphol Kinesiol ; 6(3)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34449658

RESUMO

The purpose of this study was to investigate the effects of listening to preferred versus non-preferred warm-up music on anaerobic sprint performance in Division I NCAA female athletes. Female collegiate athletes (n = 14) were recruited for this study. In a counterbalanced, crossover study design, participants completed two separate visits, each with a different warm-up music condition: preferred (Pref) or non-preferred (Non-pref). During each visit, participants completed a 3 min standardized cycling warm-up at 50 Watts while listening to Pref or Non-pref music. Following this, participants completed 3 × 15 s Wingate Anaerobic Tests (WAnTs) with a 2 min active recovery period in between tests. Motivation to exercise was measured immediately following the warm-up (WU), WAnT1, WAnT2, and WAnT3. The rate of perceived exertion (RPE) was also measured after each WAnT. Each visit was separated by a minimal recovery period of 48 h. Mean power, total work, RPE, and motivation were analyzed. Mean power (p = 0.044; d = 0.91) and total work (p = 0.045; d = 0.78) were significantly higher during the Pref music condition versus Non-pref. RPE remained unchanged regardless of condition (p = 0.536; d = 0.01). Motivation was significantly higher with Pref warm-up music compared to Non-pref (p < 0.001; d = 1.55). These results show that listening to Pref warm-up music has an ergogenic benefit during repeated sprints in comparison to Non-pref music and improves motivation to exercise. Listening to warm-up music prior to high-intensity repeated exercise may aid in optimizing performance and training in collegiate athletes.

10.
Artigo em Inglês | MEDLINE | ID: mdl-34209617

RESUMO

The purpose of this study was to examine the effects of short-term Golden Root Extract (GRE; Rhodiola rosea) supplementation on blood lactate, catecholamines, and performance during repeated bench press exercise. Resistance-trained males (n = 10) participated in this study. In a double-blinded, crossover, counterbalanced study design, participants supplemented with either 1500 mg/day of GRE or placebo (PL; gluten-free cornstarch) for 3 days prior to experimentation. An additional 500 mg dose was ingested 30 min prior to exercise testing. During each exercise trial, participants completed 2 repetitions of bench press at 75% of one-repetition maximum (1RM) as explosively as possible. A linear position transducer was used to measure mean concentric velocity. After 5 min of rest, participants completed 3 sets × repetitions to failure (RTF) at 75% 1RM separated by 2 min of rest between each set. A capillary blood sample was obtained pre- (PRE) and immediately post- (POST) exercise to measure blood concentrations lactate (LA), epinephrine (EPI), and norepinephrine (NE). Mean concentric velocity was significantly higher with GRE when compared to PL (p = 0.046). However, total RTF were significantly lower with GRE versus PL (p < 0.001). Regardless of treatment, LA was significantly higher Post versus Pre (p < 0.001), but GRE resulted in greater Post values compared to PL (p = 0.049). EPI and NE increased in both conditions Pre to Post (p < 0.001). However, Pre NE was significantly higher with GRE versus PL (p = 0.008). Findings indicate that short-term GRE supplementation increases mean bench press velocity but decreases bench press repetition volume. Furthermore, GRE resulted in higher NE levels and blood lactate following exercise. Thus, supplementing with GRE may enhance explosive resistance training performance but may also impair upper body strength-endurance.


Assuntos
Treinamento Resistido , Rhodiola , Suplementos Nutricionais , Exercício Físico , Humanos , Masculino , Força Muscular , Músculo Esquelético , Extratos Vegetais/farmacologia
11.
J Am Soc Mass Spectrom ; 32(5): 1224-1236, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33793219

RESUMO

Isotope ratio (IR) analysis of natural abundance uranium presents a formidable challenge for mass spectrometry (MS): the required spectral dynamic range needs to enable the quantitatively accurate measurement of the 234UO2 species present at ∼0.0053% isotopic abundance. We address this by empowering a benchtop Orbitrap Fourier transform mass spectrometer (FTMS) coupled with the liquid sampling-atmospheric pressure glow discharge (LS-APGD) ion source and an external high-performance data acquisition system, FTMS Booster X2. The LS-APGD microplasma has demonstrated impressive capabilities regarding elemental and IR analysis when coupled with Orbitrap FTMS. Despite successes, there are limitations regarding the dynamic range and mass resolution that stem from space charge effects and data acquisition and processing restrictions. To overcome these limitations, the FTMS Booster was externally interfaced to an LS-APGD Q Exactive Focus Orbitrap FTMS to obtain time-domain signals (transients) and to process unreduced data. The unreduced time-domain data acquisition with user-controlled processing permit the evaluation of the effects of in-hardware transient phasing, increased transient lengths, advanced transient coadding, varying the length of a transient to be processed with a user-defined time increment, and the use of absorption-mode FT (aFT) processing methods on IR analysis. The added capabilities extend the spectral dynamic range of the instrument to at least 4-5 orders of magnitude and provide a resolution improvement from ∼70k to 900k m/Δm at 200 m/z. The empowered LS-APGD Orbitrap platform allows for the simultaneous measurement of 234UO2 and the prominent 235UO2 and 238UO2 isotopic species at their natural abundances, ultimately yielding improvements in performance when compared to previous uranium IR results on this same Q Exactive Focus instrument.

12.
Percept Mot Skills ; 128(3): 1183-1196, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33722102

RESUMO

The purpose of this study was to examine the effects of listening to pre-exercise music on bench press performance. We recruited 10 resistance trained males (M age= 22.8, SD = 5.8 years; M height= 173.7, SD = 8.3 cm; M body mass = 81.0, SD = 18.2 kg) for this crossover counterbalanced research design. Participants completed two bench press exercise trials of (a) No music (NM), and (b) Pre-exercise music (PreExM) separated by at least 48 hours. For each trial, following a warm-up, participants listened to music or no music for three minutes. After this 3-minute period, they completed one set of bench press repetitions with maximum explosive intent at 75% one repetition maximum (1 RPM). We used a rotary encoder to measure power and velocity of barbell movement. After a 3-minute rest during which they again listened to music or no music, participants completed another set of repetitions to failure (RTF) at 75% of 1RM. Immediately following this second set of repetitions, we measured exercise motivation with a visual analog scale (VAS). We found that the PreExM condition increased mean power output (p = 0.005; d = 0.792) and barbell velocity (p = 0.015; d = 0.722). RTF were significantly higher during the PreExM versus NM trial (p = 0.002; d = 0.985), and motivation was significantly higher in the PreExM trial versus NM (p = 0.001; d = 0.932). These findings suggest improved muscle power explosiveness and strength-endurance when listening to music before a bench press exercise. From a practical standpoint, athletes who have the option of listening to music immediately prior to resistance exercise may benefit from its use.


Assuntos
Música , Treinamento Resistido , Adulto , Terapia por Exercício , Humanos , Masculino , Força Muscular , Músculo Esquelético , Levantamento de Peso , Adulto Jovem
13.
Artigo em Inglês | MEDLINE | ID: mdl-33477729

RESUMO

One-third of Americans with diabetes will develop diabetic retinopathy (DR), the leading cause of blindness in working-age Americans. Social determinants of health (SDOHs) are conditions in a person's environment that may impact health. The objective of this study was to determine whether there is an association between SDOHs and DR in patients with type II diabetes. This cross-section study used data from the 2018 Behavioral Risk Factor Surveillance System (BRFSS). This study included people with self-reported diabetes in the US in 2018 (n = 60,703). Exposure variables included homeownership, marital status, income, health care coverage, completed level of education, and urban vs. rural environment. The outcome variable was DR. Logistic regression analysis were applied to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Alaskan Native/Native American (OR 2.11; 95% CI: 1.14-3.90), out of work (OR 2.82; 95% CI: 1.62-4.92), unable to work (OR 2.14; 95% CI: 1.57-2.91), did not graduate high school (OR 1.91; 95% CI: 1.30-2.79), only graduated high school (OR 1.43; 95% CI 1.08-1.97), or only attended college or technical school without graduating (OR 1.42; 95% CI: 1.09-1.86) were SDOHs associated with DR in patients with diabetes. Health care providers should identify these possible SDOHs affecting their diabetic patients.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Retinopatia Diabética/epidemiologia , Humanos , Prevalência , Fatores de Risco , Autorrelato , Determinantes Sociais da Saúde
14.
Artigo em Inglês | MEDLINE | ID: mdl-33430250

RESUMO

Diurnal fluctuations in power output have been well established with power loss typically occurring in morning (AM) times. Beetroot juice (BRJ) is a source of dietary nitrate that possess ergogenic properties, but it is unknown if ingestion can mitigate performance decrements in the morning. The purpose of this study was to examine the effects of acute BRJ supplementation on diurnal fluctuations in anaerobic performance in trained sprinters. Male Division 1 National Collegiate Athletic Association (NCAA) sprinters (n = 10) participated. In a double-blinded crossover study design, participants completed three counterbalanced exercise trials under different conditions: Morning-placebo (8:00 HR, AM-PL), Morning-BRJ (8:00 HR, AM-BRJ), and Afternoon-no supplement (15:00 HR, PM). For each trial, participants completed 3 × 15 s Wingate anaerobic tests separated by 2 min of rest. Each trial was separated by a 72 h washout period. Mean power output (p = 0.043), anaerobic capacity (p = 0.023), and total work (p = 0.026) were significantly lower with the AM-PL condition compared to PM. However, BRJ supplementation prevented AM losses of mean power output (p = 0.994), anaerobic capacity (p = 0.941), and total work (p = 0.933) in the AM-BRJ compared to the PM condition. Rate of perceived exertion was not significantly different between any conditions (p = 0.516). Heart rate was significantly lower during the AM-BRJ condition compared to AM-PL (p = 0.030) and PM (p < 0.001). Findings suggest anaerobic capacity suffers during AM versus PM times in trained sprinters, but BRJ ingestion abolishes AM-associated decrements in performance.


Assuntos
Beta vulgaris , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Sucos de Frutas e Vegetais , Humanos , Masculino , Nitratos
15.
J Phys Chem B ; 125(1): 211-218, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33373244

RESUMO

Online extraction of fission products, such as the medical isotope Mo-99, is a key advantage of the proposed molten salt nuclear reactor design. The chemical and structural behavior of Mo solvated in fluoride salt has been relatively unknown. Ab initio molecular dynamics simulations were employed to examine the behavior of molybdenum in the molten salt FLiNaK (LiF-NaF-KF) for oxidation states between 0 and 6+. Mo complexation was found to vary with the Mo oxidation state, with lower oxidation states tending to result in complexes with more molybdenum ions. Complexes containing multiple Mo ions were observed for all Mo oxidation states studied except 5+ and 6+. A relationship between the solubility of a complex and electronic isolation of a complex in a molten salt is explored using the Bader atoms in molecule electron density partitioning scheme, with more volatile complexes exhibiting greater electronic isolation. The impacts of UF4 and H2O on the predominant molybdenum species are also considered. While no impacts on Mo behavior by UF4 were observed, Mo-O interactions may inhibit the formation of complexes containing multiple Mo ions.

16.
J Strength Cond Res ; 35(6): 1650-1655, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30531416

RESUMO

ABSTRACT: Ballmann, CG, McCullum, MJ, Rogers, RR, Marshall, MR , and Williams, TD. Effects of preferred vs. nonpreferred music on resistance exercise performance. J Strength Cond Res 35(6): 1650-1655, 2021-The purpose of this study was to examine the effects of listening to preferred vs. nonpreferred music on resistance exercise performance. Twelve resistance-trained college-aged males (age = 20.5 ± 1.24 years, height = 183.9 ± 6.8 cm, and body mass = 97.0 ± 18.2 kg) were recruited for this study. In a within-groups counterbalanced study design, subjects either listened to preferred or nonpreferred music during a bench press exercise test. Subjects completed as many repetitions as possible at 75% of their 1 repetition maximum with maximum explosive intent. Power and velocity of the barbell movement was measured for the first 3 repetitions using a linear position transducer. Motivation was measured using a visual analog scale immediately after exercise. Each exercise trial was separated by a 48-hour washout period. Results indicate that listening to preferred music increased overall bench press repetitions completed (p = 0.005; effect size [ES] = 0.84). During the first 3 repetitions, mean velocity (p = 0.001; ES = 1.6), relative mean power (p = 0.012; ES = 0.55), peak velocity (p = 0.011; ES = 0.99), and peak power (p = 0.009; ES = 0.35) were higher while listening to preferred music vs. nonpreferred music. Finally, motivation during the lift (p < 0.001; ES = 5.9) was significantly higher while listening to preferred vs. nonpreferred music. Current findings suggest that listening to preferred music by the individual results in greater performance than nonpreferred during resistance exercise. Athletes may benefit from the option to listen to their preferred music to increase motivation and resistance exercise performance.


Assuntos
Música , Treinamento Resistido , Adulto , Exercício Físico , Humanos , Masculino , Motivação , Força Muscular , Levantamento de Peso , Adulto Jovem
17.
Artigo em Inglês | MEDLINE | ID: mdl-35010630

RESUMO

The purpose of this study was to assess the effect of two fluid intake protocols on alertness and reaction time before and after fluid intake. Healthy college-age males (n = 12) followed two fluid intake protocols on separate occasions: (1) prescribed fluid (PF) and fluid restricted (FR). In PF, participants were instructed to consume 500 mL of fluid the night prior to and the morning of data collection. In FR, participants were instructed to refrain from the consumption of fluid for 12 h. To assess hydration status, urine specific gravity and urine color were measured. Participants perceived level of thirst and alertness were also recorded. Participants then completed visuomotor reaction time tests using the Dynavision LED board, using both a central visuomotor test and a peripheral visuomotor test (PVRT) prior to (1) and following (2) the ingestion of 100 mL of water. Participants displayed significantly improved PVRT in PF state as compared to FR (PF1 = 1.13 ± 0.16, PF2 = 1.04 ± 0.14; FR1 = 1.27 ± 0.27, FR2 = 1.18 ± 0.20; p = 0.038, ηp2 = 0.363). Both CVRT and PVRT improved over time, following the ingestion of 100 mL of fluid. Participants in the PF state were also significantly more alert than participants in the FR state (PF = 4 ± 2, FR = 5 ± 2; p = 0.019, ES = 0.839). Collectively, perceived alertness and PVRT were negatively impacted by FR.


Assuntos
Desidratação , Ingestão de Líquidos , Humanos , Masculino , Sede , Urinálise , Equilíbrio Hidroeletrolítico
18.
Res Q Exerc Sport ; 92(3): 492-499, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-32633217

RESUMO

Purpose: The purpose of this study was to investigate how time-of-day training preference influences resistance-exercise performance. Methods: Resistance trained males (n = 12) were recruited for this study. In a crossover, counterbalanced design, participants completed two separate bench-press exercise trials at different times of day: (a) morning (AM; 8:00 hr) and (b) evening (PM; 16:00 hr). Participants answered a questionnaire on time-of-day training preference and completed a preferred (PREF) and nonpreferred (NON-PREF) time-of-day trial. For each trial, motivation was measured using a visual analog scale prior to exercise. Participants completed 2 sets × 2 repetitions at 75% 1-RM with maximum explosiveness separated by 5 min of rest. Mean barbell velocity was measured using a linear position transducer. Participants then completed 1 set × repetitions to failure (RTF) at 75% 1-RM. Rate of perceived exertion (RPE) was measured immediately following exercise. Results: Regardless of preference, velocity (p = .025; effect size (ES) = 0.43) was higher during the PM versus AM trial. However, there were no significant differences in velocity (p = .368; ES = 0.37) between PREF and NON-PREF time of day. There were no significant differences for repetitions between PREF and NON-PREF times (p = .902; ES = 0.03). Motivation was higher in the PREF time versus NON-PREF (p = .015; ES = 0.68). Furthermore, RPE was significantly lower during the PREF time of day (p = .048; 0.55). Conclusions: Despite higher barbell velocity collectively at PM times, time-of-training preference did not largely influence resistance-exercise performance, while motivation is higher and RPE is lower during preferred times.


Assuntos
Motivação/fisiologia , Força Muscular/fisiologia , Treinamento Resistido/métodos , Levantamento de Peso/fisiologia , Estudos Cross-Over , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
19.
Percept Mot Skills ; 128(1): 338-352, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32741251

RESUMO

The purpose of this study was to investigate physical and cognitive performance during dual task conditions of upper-extremity (UE) or full-body (FB) rowing exercise. In a crossover counterbalanced design, college-aged male and female participants completed five conditions: (a) Sitting, (b) Single task UE rowing, (c) Single task FB rowing, (d) Dual task UE rowing, and (e) Dual task FB rowing. For single task UE and FB rowing conditions, participants were asked to row as hard as possible. After sitting and dual-task conditions, we administered the Paced Auditory Serial Addition Test (PASAT) and a word-list memory test. We analyzed participants' absolute differences (single task - dual task) in power output and their cognitive test scores to compare UE and FB rowing. There were no significant absolute differences from sitting to dual task conditions of UE and FB rowing for either PASAT (p = 0.958) or word list memory (p = 0.899) cognitive scores. Absolute power output loss from single to dual task conditions was significantly higher in FB versus UE for PASAT (p = 0.039; d = 0.54) and word list memory (p = 0.021; d = 0.66) in the dual task condition. These results suggest that, while cognitive performance was preserved regardless of the amount of muscle mass activated during dual task rowing, physical performance suffered more during FB than UE rowing under the dual task condition. These findings have important implications for optimizing cognitive and physical performance in dual task situations.


Assuntos
Cognição , Análise e Desempenho de Tarefas , Exercício Físico , Feminino , Marcha , Humanos , Masculino , Extremidade Superior , Adulto Jovem
20.
Microorganisms ; 8(12)2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33291570

RESUMO

Neutrophils and eosinophils are granulocytes that have very distinct functions. Neutrophils are first responders to external threats, and they use different mechanisms to control pathogens. Phagocytosis, reactive oxygen species, and neutrophil extracellular traps (NETs) are some of the mechanisms that neutrophils utilize to fight pathogens. Although there is some controversy as to whether NETs are in fact beneficial or detrimental to the host, it mainly depends on the biological context. NETs can contribute to disease pathogenesis in certain types of diseases, while they are also undeniably critical components of the innate immune response. On the contrary, the role of eosinophils during host immune responses remains to be better elucidated. Eosinophils play an important role during helminthic infections and allergic responses. Eosinophils can function as effector cells in viral respiratory infections, gut bacterial infections, and as modulators of immune responses by driving the balance between Th1 and Th2 responses. In particular, eosinophils have biological activities that appear to be quite similar to those of neutrophils. Both possess bactericidal activity, can activate proinflammatory responses, can modulate adaptive immune responses, can form extracellular traps, and can be beneficial or detrimental to the host according to the underlying pathology. In this review we compare these two cell types with a focus on highlighting their numerous similarities related to extracellular traps.

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