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1.
PeerJ ; 12: e17323, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38726377

RESUMEN

The rice receptor kinase XA21 confers broad-spectrum resistance to Xanthomonas oryzae pv. oryzae (Xoo), the causal agent of rice bacterial blight disease. To investigate the relationship between the expression level of XA21 and resulting resistance, we generated independent HA-XA21 transgenic rice lines accumulating the XA21 immune receptor fused with an HA epitope tag. Whole-genome sequence analysis identified the T-DNA insertion sites in sixteen independent T0 events. Through quantification of the HA-XA21 protein and assessment of the resistance to Xoo strain PXO99 in six independent transgenic lines, we observed that XA21-mediated resistance is dose dependent. In contrast, based on the four agronomic traits quantified in these experiments, yield is unlikely to be affected by the expression level of HA-XA21. These findings extend our knowledge of XA21-mediated defense and contribute to the growing number of well-defined genomic landing pads in the rice genome that can be targeted for gene insertion without compromising yield.


Asunto(s)
Resistencia a la Enfermedad , Oryza , Enfermedades de las Plantas , Proteínas de Plantas , Plantas Modificadas Genéticamente , Xanthomonas , Xanthomonas/genética , Oryza/microbiología , Oryza/genética , Oryza/inmunología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Serina-Treonina Quinasas
2.
Cell Stem Cell ; 31(5): 585-586, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38701752

RESUMEN

Stem cell therapy has emerged as a promising area of scientific investigation, sparking considerable interest, especially in spinal cord injury (SCI). Sun et al.1 discover that the extracellular matrix (ECM) from the neonatal spinal cord transmits biochemical signals to endogenous axons, thus promoting axonal regeneration.


Asunto(s)
Traumatismos de la Médula Espinal , Médula Espinal , Humanos , Traumatismos de la Médula Espinal/terapia , Animales , Recién Nacido , Matriz Extracelular/metabolismo , Adulto , Regeneración Nerviosa
3.
J Strength Cond Res ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38662931

RESUMEN

ABSTRACT: Sax van der Weyden, M, Merrigan, JJ, Newman, K, Hahn, J, and Martin, J. Army Combat Fitness Test scores moderate cognitive function improvements after a ruck march: A hierarchical linear model approach. J Strength Cond Res XX(X): 000-000, 2024-Heavy load carriage is a common task for military personnel and can lead to undue physical and mental fatigue. The purpose of this study was to assess effects of load carriage on cognitive function (CF) and the role individual characteristics play in CF responses. Anthropometrics/body composition, demographics, and Army Combat Fitness Test (ACFT) scores were gathered from 47 Reserve Officers' Training Corps cadets. Cadets' CF was assessed through the concentration task grid (CTG) before (preruck), immediately after (postruck), and 3 weeks after (follow-up) a 16.09- to 19.31-km ruck march. Hierarchical linear modeling was used, with α < 0.05. The final model revealed growth, or improvement, in CF from preruck to postruck with growth decelerating, but still improved, at follow-up. The load carriage bout improved CF in most cadets, with average growth from 5.67- to 7.20-grid squares found. However, postruck CF did not return to the same level as a controlled follow-up (9.69). Sex (2.46, female), familiarity with the CTG (1.99), ACFT total scores (0.009), and relative ruck mass (-0.09) were all significant predictors of postruck CF. Army Combat Fitness Test scores (0.008) were also significant predictors of the slope between preruck and postruck, such that an ACFT score 59 points above average would result in a 1-grid square greater improvement in CF postruck. The significance of ACFT scores, lower relative ruck mass, and familiarization highlights the importance physical and mental preparation for desirable CF outcomes after occupational tasks.

4.
Work ; 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38339952

RESUMEN

BACKGROUND: Despite the physical nature of the occupation many firefighters have low levels of physical fitness which is associated with poor performance of occupational tasks and increased injury rates. For many fire departments an initial step in promoting health and wellness within the department is to conduct annual fitness testing. OBJECTIVE: To examine the effects of implementing a consequential fitness assessment within a fire department. METHODS: A retrospective repeated measures design was used to analyze annual fitness assessment data of professional firefighters (n = 1415) from 2019 to 2022 within a large urban fire department located in the mid-Atlantic region of the United States. The fitness tests included assessments of pull-ups, push-ups, sit-ups, aerobic capacity, and body composition. Repeated measure analyses of variances (ANOVAs) assessed the effect of year and a 2-way ANOVA was conducted to investigate the effects of sex and age on fitness measures on 2022 data. RESULTS: All fitness measures were found to be maintained over the 4-year period. Significant main effects of age and sex across all fitness measures, but no significant interactions were found. Older firefighters (50 + years) exhibited lower performance (p <  0.001, d >  0.80) on muscular fitness assessments than young firefighters (20-29 years). A large effect of sex (males >  females) was found for pull-ups (d = 1.04), push-ups (d = 1.23), and aerobic capacity (d = 1.38). CONCLUSIONS: The results suggest that implementing a consequential fitness assessment could help maintain firefighters' fitness levels over a multi-year period.

5.
Nat Commun ; 15(1): 218, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233418

RESUMEN

Over the past decade, stereotactically placed electrodes have become the gold standard for deep brain recording and stimulation for a wide variety of neurological and psychiatric diseases. Current electrodes, however, are limited in their spatial resolution and ability to record from small populations of neurons, let alone individual neurons. Here, we report on an innovative, customizable, monolithically integrated human-grade flexible depth electrode capable of recording from up to 128 channels and able to record at a depth of 10 cm in brain tissue. This thin, stylet-guided depth electrode is capable of recording local field potentials and single unit neuronal activity (action potentials), validated across species. This device represents an advance in manufacturing and design approaches which extends the capabilities of a mainstay technology in clinical neurology.


Asunto(s)
Encéfalo , Neuronas , Humanos , Encéfalo/fisiología , Electrodos , Potenciales de Acción/fisiología , Neuronas/fisiología , Electrodos Implantados
6.
J Sport Rehabil ; 33(2): 128-134, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37758260

RESUMEN

CLINICAL SCENARIO: Dancing is a demanding esthetic activity with dancers having an 85% annual injury incident rate when performing complex dance motor skills. Teachers and clinicians use a combination of external and internal attentional cues when teaching dancers motor skills and when working on rehabilitation programs with injured dancers, respectively. External attentional focus (ie, focusing on movement outcome) reportedly results in superior performance than internal attentional focus (ie, focus on body movements). Interestingly, dancers reportedly often adopt an internal focus when dancing. Still, limited literature exists examining the effects of attentional focus on dancers' performance. CLINICAL QUESTION: How does attentional focus (external or internal) impact performance in dancers? SUMMARY OF KEY FINDINGS: Four original quasi-experimental studies met inclusion criteria. In the current examination, we found mixed results about the impact of attentional focus in dancers. Specifically, using an external attentional focus resulted in better performance in 2 studies, but these findings were limited to lesser experienced dancers. Experienced dancers did not have any physical performance differences when using external or internal focus. Internal focus also did not negatively affect dancers' performance in 2 studies. Some authors noted positive motivational effects (eg, increased perceived competence) when dancers used external focus. CLINICAL BOTTOM LINE: Low-quality evidence exists supporting the notion that in less experienced dance students, external focus improves performance. In experienced dancers, the type of attentional focus did not impact performance. External focus provides positive mental effects. Thus, clinicians working with dancers can integrate individualized feedback according to dancer level, with a preference toward external focus due to positive mental effects, to design optimal training and rehabilitation programs. STRENGTH OF RECOMMENDATION: Grade B evidence exists supporting the notion that an external attentional focus improves performance in less experienced dance students and also has positive mental effects. Internal attentional focus does not impede experienced dancers' performance.


Asunto(s)
Baile , Humanos , Baile/lesiones , Atención , Rendimiento Físico Funcional , Destreza Motora
7.
Sports Health ; 16(3): 390-395, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-36929850

RESUMEN

CONTEXT: After anterior cruciate ligament (ACL) reconstruction (ACLR), athletes commonly undergo prolonged rehabilitation (eg, 9-12 months), but few actually return to preinjury sports activities. The nature (composition, configuration) of an ACL rehabilitation program (ACL-RP) is an important factor in determining rehabilitation outcomes; however, details about the nature of ACL-RPs are reported inconsistently in research studies. To guide future research reporting to support clinical translation and implementation of ACL-RPs, it is necessary to describe the nature, reporting, and outcomes of ACL-RPs in the current literature. OBJECTIVE: The purpose of this scoping review was to understand the nature and reporting of various ACL-RPs that address musculoskeletal, biomechanical, functional, or patient-reported outcome measures in adult and pediatric athletes with ACLR. DATA SOURCES: Articles were selected from searches in 5 electronic databases (PubMed, EbscoHost [MEDLINE, SportDiscus, CINAHL Plus], PROQuest, Cochrane, and Embase). STUDY SELECTION: Studies were included if they evaluated a post-ACL-RP that implemented strength, balance, plyometric, change of direction running, and/or agility running and included self-reported physical function, quality of life, or pain outcomes. STUDY DESIGN: Scoping review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews (PRISMA-ScR) guidelines. LEVEL OF EVIDENCE: Level 4. DATA EXTRACTION: Data were extracted and synthesized to evaluate the reporting of acute program variables (APVs) and exercise descriptors (EDs); 17 studies were included in the final synthesis. RESULTS: Studies reported between 0% and 67% of the APVs and EDs combined. Only 2 studies were considered to have adequate reporting of both APVs and EDs. CONCLUSION: Inadequate reporting of APVs and EDs in past studies restricts the translation and implementation of existing research-based ACL-RPs to present-day clinical contexts.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Adulto , Humanos , Niño , Lesiones del Ligamento Cruzado Anterior/cirugía , Calidad de Vida , Volver al Deporte , Atletas , Medición de Resultados Informados por el Paciente
8.
Syst Biol ; 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37941464

RESUMEN

For much of terrestrial biodiversity, the evolutionary pathways of adaptation from marine ancestors are poorly understood, and have usually been viewed as a binary trait. True crabs, the decapod crustacean infraorder Brachyura, comprise over 7,600 species representing a striking diversity of morphology and ecology, including repeated adaptation to non-marine habitats. Here, we reconstruct the evolutionary history of Brachyura using new and published sequences of 10 genes for 344 tips spanning 88 of 109 brachyuran families. Using 36 newly vetted fossil calibrations, we infer that brachyurans most likely diverged in the Triassic, with family-level splits in the late Cretaceous and early Paleogene. By contrast, the root age is underestimated with automated sampling of 328 fossil occurrences explicitly incorporated into the tree prior, suggesting such models are a poor fit under heterogeneous fossil preservation. We apply recently defined trait-by-environment associations to classify a gradient of transitions from marine to terrestrial lifestyles. We estimate that crabs left the marine environment at least seven and up to 17 times convergently, and returned to the sea from non-marine environments at least twice. Although the most highly terrestrial- and many freshwater-adapted crabs are concentrated in Thoracotremata, Bayesian threshold models of ancestral state reconstruction fail to identify shifts to higher terrestrial grades due to the degree of underlying change required. Lineages throughout our tree inhabit intertidal and marginal marine environments, corroborating the inference that the early stages of terrestrial adaptation have a lower threshold to evolve. Our framework and extensive new fossil and natural history datasets will enable future comparisons of non-marine adaptation at the morphological and molecular level. Crabs provide an important window into the early processes of adaptation to novel environments, and different degrees of evolutionary constraint that might help predict these pathways.

9.
CBE Life Sci Educ ; 22(4): ar40, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37751502

RESUMEN

Students' beliefs about their abilities (called "lay theories") affect their motivations, behaviors, and academic success. Lay theories include beliefs about the potential to improve intelligence (mindset), who (i.e., everyone or only some people) has the potential to be excellent in a field (universality), and whether reaching excellence in a field requires raw intellectual talent (brilliance). Research demonstrates that each of these beliefs influences students' educational experiences and academic outcomes. However, it remains unclear whether they represent distinct latent constructs or are susceptible to the "jangle fallacy" (i.e., different names given to the same underlying construct). We conducted a multiphase, mixed-methods study to 1) evaluate whether mindset, universality, and brilliance beliefs represent conceptually and empirically discriminable concepts, and 2) evaluate whether mindset, universality, and brilliance beliefs contribute unique explanatory value for both psychosocial (e.g., sense of belonging) and academic outcomes (e.g., course grades). To address these questions, we developed and collected validity evidence for a new measure of science and math undergraduates' lay theories, called the Undergraduate Lay Theories of Abilities (ULTrA) survey. Factor analyses suggest that mindset, brilliance, and universality are distinct and empirically discriminable constructs. Structural Equation Models indicate that each lay theory contributes unique predictive value to relevant outcomes.


Asunto(s)
Éxito Académico , Estudiantes , Humanos , Análisis Factorial , Inteligencia , Motivación
10.
Elife ; 122023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37750670

RESUMEN

How does the human brain combine information across the eyes? It has been known for many years that cortical normalization mechanisms implement 'ocularity invariance': equalizing neural responses to spatial patterns presented either monocularly or binocularly. Here, we used a novel combination of electrophysiology, psychophysics, pupillometry, and computational modeling to ask whether this invariance also holds for flickering luminance stimuli with no spatial contrast. We find dramatic violations of ocularity invariance for these stimuli, both in the cortex and also in the subcortical pathways that govern pupil diameter. Specifically, we find substantial binocular facilitation in both pathways with the effect being strongest in the cortex. Near-linear binocular additivity (instead of ocularity invariance) was also found using a perceptual luminance matching task. Ocularity invariance is, therefore, not a ubiquitous feature of visual processing, and the brain appears to repurpose a generic normalization algorithm for different visual functions by adjusting the amount of interocular suppression.


Asunto(s)
Ojo , Percepción Visual , Humanos , Animales , Algoritmos , Aves , Encéfalo
11.
Work ; 76(4): 1589-1596, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37393477

RESUMEN

BACKGROUND: The work-related stress experienced by firefighters is associated with numerous health issues. In the general population, improving physical fitness is associated with improvements in both mental and physical quality of life. OBJECTIVE: The purpose of the study was to examine whether fitter professional firefighters report greater physical and mental quality of life. METHODS: Twenty-three professional firefighters (males = 21, females = 2; age: 36.78±7.12yrs; height: 176.96±5.67 cm; weight: 88.20±16.02 kg; years of service: 8.70±6.62years) volunteered for the study. Participants completed a fitness protocol that included the wall sit and reach, Y-balance test, vertical jump, 1 repetition maximum bench press, pull-ups to failure, push-ups to failure, a plank hold and 1-mile run. The short form 36 questionnaire was used to assess overall quality of life. Firefighters were divided into "high" and "low" groups for physical and mental quality of life. Group differences in fitness parameters were assessed using a multivariate analysis of covariance with gender, age, years of service, height, and body mass as co-variates. RESULTS: Firefighters with lower mental quality of life had lower body fat percentages (p = 0.003), fat mass (p = 0.036), greater fat free mass (p = 0.015), vertical jump height (p = 0.024) and performed more pull-ups (p = 0.003). There were no significant differences in any of the fitness measures between high and low physical quality of life groups. CONCLUSION: The findings indicate that physical fitness of firefighters is not indicative of overall health. Firefighters might use exercise to cope for psychological stress and a holistic approach to improve firefighter quality of life is recommended.


Asunto(s)
Bomberos , Masculino , Femenino , Humanos , Adulto , Calidad de Vida , Autoinforme , Aptitud Física , Fuerza Muscular , Prueba de Esfuerzo/métodos
12.
J Funct Morphol Kinesiol ; 8(3)2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37489311

RESUMEN

Dance is physically demanding, requiring physical fitness (PF) that includes upper body, lower body, core fitness, and balance for successful performance. Whether PF changes as dancers advance from when they enter (freshmen) to when they graduate from their collegiate program (seniors) is unclear. We prospectively compared collegiate dancers' freshman-to-senior PF. We recorded PF in regard to upper body strength endurance (push-ups), core strength endurance (front, left-side, right-side, and extensor plank hold times), lower body power (single leg hop-SLH-distances % height; Leg Symmetry Index: LSI = higher/lower × 100, %), and balance (anterior reach balance, % leg length, LL; LSI balance = higher/lower × 100, %) in 23 female collegiate dancers (freshman age = 18.2 ± 0.6 years). Repeated measures ANOVAs (p ≤ 0.05) were used to compare measures from freshman to senior years. Across their collegiate programs, dancers' PF remained unchanged. Specifically, their upper body strength endurance push-up numbers (p = 0.93), their core strength endurance plank times (left: p = 0.44, right: p = 0.67, front: p = 0.60, p = 0.22), their SLH distances (left: p = 0.44, right: p = 0.85), and their symmetry (p = 0.16) stayed similar. Also, dancers' right leg (p = 0.08) and left leg balance (p = 0.06) remained similar, with better balance symmetry (p < 0.001) in seniors. Overall, dancers' PF did not change across their collegiate programs. Thus, female dancers' freshman PF may be an adequate baseline reference measure when devising rehabilitation programs and determining readiness-to-return-to-activity post injury.

13.
J Funct Morphol Kinesiol ; 8(3)2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37489312

RESUMEN

Sixty percent of all law enforcement officers (LEOs) experience low back pain (LBP), with the LEO duty belt (LEODB) commonly reported to be a contributing factor. The primary purpose of the study was to investigate the LEODB's effect on muscular activity and compare it to a tactical vest, which is a commonly used alternative to an LEODB. In total, 24 participants (13 male, 11 female; mass, 73.0 ± 11.1 kg; height, 169.0 ± 10.0 cm; age, 24.0 ± 5.8 years) completed a progressive series of hip hinge tasks in a single testing session. All participants completed four conditions (no belt, leather belt, nylon belt, and weight VEST) in a randomized order. Surface electromyography (sEMG) sensors were placed bilaterally on the rectus abdominus, multifidus, biceps femoris, and rectus femoris. Across all tasks, no significant effects of load on muscle activity were found for any of the muscles. Participants rated the VEST condition as more comfortable (p < 0.05) and less restrictive (p < 0.05) than either LEODB. The findings suggest an LEODB does not alter muscle activity during bodyweight hip hinging or lifting objects from the ground. Future research should examine whether changes in muscle activity occur with durations of LEODB wear more similar to an actual work shift duration for LEOs (≥8 h).

14.
Appl Ergon ; 113: 104091, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37437354

RESUMEN

Law enforcement officers are inherently at a high risk of injury and the loads they must carry during their occupational duties further increase their injury risk. It is unknown how different methods of carrying a law enforcement officer's load influence factors related to injury risk. This study assessed the effects of common law enforcement load carriage systems on muscular activity and postural stability while standing. Twenty-four participants performed single and dual-task (i.e. concurrent performance of cognitive tasks) standing while wearing a duty belt, tactical vest, and no load. The postural stability and muscle activity were measured and effects of condition and task examined. Dual task standing decreased postural stability and increased muscular activity. The belt and vest (7.2 kg each) increased muscle activity compared to control for the right abdominals, low back, right thigh. The duty belt resulted in less muscle activity in the right abdominals but more muscle activity in the left multifidus compared to the control. The findings indicate that common law enforcement load carriage systems increase muscular activity but do not affect postural stability. However, the lack of differences between the duty belt and tactical vest did not provide clear support for one load carriage system versus the other.


Asunto(s)
Aplicación de la Ley , Policia , Humanos , Muslo , Posición de Pie , Músculos
15.
J Vis ; 23(7): 10, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37450287

RESUMEN

The normal human retina contains several classes of photosensitive cell-rods for low-light vision, three cone classes for daylight vision, and intrinsically photosensitive retinal ganglion cells (ipRGCs) expressing melanopsin for non-image-forming functions, including pupil control, melatonin suppression, and circadian photoentrainment. The spectral sensitivities of the photoreceptors overlap significantly, which means that most lights will stimulate all photoreceptors to varying degrees. The method of silent substitution is a powerful tool for stimulating individual photoreceptor classes selectively and has found much use in research and clinical settings. The main hardware requirement for silent substitution is a spectrally calibrated light stimulation system with at least as many primaries as there are photoreceptors under consideration. Device settings that will produce lights to selectively stimulate the photoreceptor(s) of interest can be found using a variety of analytic and algorithmic approaches. Here we present PySilSub (https://github.com/PySilentSubstitution/pysilsub), a novel Python package for silent substitution featuring flexible support for individual colorimetric observer models (including human and mouse observers), multiprimary stimulation devices, and solving silent substitution problems with linear algebra and constrained numerical optimization. The toolbox is registered with the Python Package Index and includes example data sets from various multiprimary systems. We hope that PySilSub will facilitate the application of silent substitution in research and clinical settings.


Asunto(s)
Visión de Colores , Luz , Ratones , Humanos , Animales , Células Fotorreceptoras Retinianas Conos/fisiología , Células Ganglionares de la Retina/fisiología , Células Fotorreceptoras Retinianas Bastones/fisiología , Opsinas de Bastones
16.
J Dance Med Sci ; 27(2): 92-98, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37264640

RESUMEN

INTRODUCTION: Sleep is essential for athletes and dancers to optimize recovery. Poor sleep negatively affects cognitive function and injury risk in athletes. Increased athletic participation (hours) is associated with decreased total sleep and quality in athletes. Still, information about how sleep is related with exposure hours and injury in collegiate dancers remains unclear. We examined the relationships among the Athlete Sleep Behavior Questionnaire (ASBQ), dance exposure hours (DEHr), and injuries in collegiate dancers over a 7 -month period (August 2019-February 2020). METHODS: Seventy-two dancers (58 female, 14 male; 19.7 ± 1.4 years) completed the 18 question ASBQ at the start of each month (Scale:1 = Never, 5 = Always; Global Scores ≤36 = "good sleep behavior" and ≥42 = "poor sleep behavior"). A DEHr was recorded as 1 hour of dance participation in class, rehearsal, or performance. Injuries were defined as any condition where the dancer sought medical attention, and we calculated an injury rate for total injuries (IR/1000 DEHr). Pearson correlations examined relationships among ASBQ, DEHr, and injuries (P ≤ .05). RESULTS: Dancers participated in 467.8 ± 45.7 DEHr over 7 months, with 14 dancers suffering 18 injuries (IR = 0.5/1000-DEHr; 95% CI:0.3-0.8). Overall, dancers reported poor sleep behaviors (42.6 ± 6.4). ASBQ scores, DEHr, and injuries in August-October, and December-February were not related, except for a weak positive relationship between ASBQ scores and DEHr in November (r = .28, P = .04). CONCLUSIONS: Sleep, DEHr, and injuries were inconsistently related in collegiate dancers. Sleep and DEHr were only correlated during the month where dancers had 2 performance weeks. While we did not observe this relationship every month, performance weeks may have negatively affected sleep in November. Despite consistent poor sleep, sleep did not seem to negatively affect injury risk during the 7 -month study period. Future researchers should validate the ASBQ in dancers.


Asunto(s)
Baile , Humanos , Masculino , Femenino , Baile/lesiones , Encuestas y Cuestionarios , Sueño , Cognición , Universidades
18.
Occup Environ Med ; 80(8): 455-461, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37258271

RESUMEN

OBJECTIVES: To examine the effects of implementing a consequential fitness assessment (pull-ups, curl-ups, push-ups, 3 min step test) in a fire department on an individual level. METHODS: We used a repeated-measures design to analyse fitness assessment data from 2019 to 2020 in Northern Virginia. A total of 631 professional firefighters completed the fitness assessment in both years. Repeated measures analysis of variances (ANOVAs) and multiple regression modelling were used to examine the effects of the fitness assessment and factors associated with changes in fitness, respectively. RESULTS: Overall all aspects of fitness improved over the first year of implementation with a majority of firefighters improved on all components of the fitness assessment except for pull-ups (16.1% improved). Greater levels of baseline fitness and being female were negatively associated with changes in all fitness measures. Older firefighters had smaller changes in pull-up, curl-up and push-up performance. CONCLUSIONS: During the first year of fitness assessment implementation, the fire department generally improved. The findings suggest that fire departments which enforce mandatory fitness assessments must establish policies for dealing with inadequate performance and offer resources to aid individual firefighters.


Asunto(s)
Prueba de Esfuerzo , Bomberos , Humanos , Femenino , Masculino , Aptitud Física/fisiología , Ejercicio Físico , Análisis de Varianza
19.
Sensors (Basel) ; 23(8)2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37112391

RESUMEN

Law enforcement officers (LEOs) commonly wear a duty belt (DB) or tactical vest (TV) and from prior findings, these forms of load carriage (LC) likely alter muscular activity. However, studies on the effects of LEO LC on muscular activity and coordination are limited in the current literature. The present study examined the effects of LEO load carriage on muscular activity and coordination. Twenty-four volunteers participated in the study (male = 13, age = 24.5 ± 6.0 years). Surface electromyography (sEMG) sensors were placed on the vastus lateralis, biceps femoris, multifidus, and lower rectus abdominus. Participants completed treadmill walking for two load carriage conditions (duty belt and tactical vest) and a control condition. Mean activity, sample entropy and Pearson correlation coefficients were computed for each muscle pair during the trials. The duty belt and tactical vest resulted in an increase in muscle activity in several muscles; however, no differences between the duty belt and tactical vest were found. Consistently across the conditions, the largest correlations were observed between the left and right multifidus (r = 0.33-0.68) and rectus abdominus muscles (0.34-0.55). There were statistically small effects (p < 0.05, η2 = 0.031 to 0.076) of the LC on intermuscular coordination. No effect (p > 0.05) of the LC on sample entropy was found for any muscle. The findings indicate that LEO LC causes small differences in muscular activity and coordination during walking. Future research should incorporate heavier loads and longer durations.


Asunto(s)
Aplicación de la Ley , Caminata , Humanos , Masculino , Adolescente , Adulto Joven , Adulto , Caminata/fisiología , Policia , Electromiografía , Músculo Cuádriceps , Músculo Esquelético/fisiología
20.
Sports (Basel) ; 11(4)2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37104162

RESUMEN

BACKGROUND: There are contradictory findings in the literature on whether an acute bout of aerobic exercise leads to a post-exercise improvement in cognitive function (CF). Moreover, participants used in the published literature are not representative of the racial make-up of sport or tactical populations. METHODS: A randomized crossover design was incorporated, with participants randomly consuming water or a carbohydrate sports drink within the first 3 min of a graded maximal exercise test (GMET) conducted in a laboratory. Twelve self-identified African American participants, (seven males, five females, age = 21.42 ± 2.38 years, height = 174.94 ± 12.55 cm, mass = 82.45 ± 33.09 kg) completed both testing days. Participants completed the CF tests immediately pre- and post-GMET. CF was assessed with the Stroop color and word task (SCWT) and concentration task grid (CTG). Participants completed the GMET when they reported a score of 20 on the Borg ratings of perceived exertion scale. RESULTS: Time to complete the SCWT incongruent task (p < 0.001) and CTG performance (p < 0.001) significantly improved post-GMET in both conditions. VO2max was positively correlated with pre- and post-GMET SCWT performance. CONCLUSIONS: The findings of our study suggest that an acute bout of maximal exercise significantly improves CF. Additionally, cardiorespiratory fitness is positively associated with CF in our sample of student athletes from a historically Black college and university.

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