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1.
PLoS One ; 19(6): e0302647, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38857238

RESUMEN

The primary aim of this study was to present the physical profile of female cricketers. Secondary, was to assess any differences between playing standard (professional vs. non-professional) and position (seam bowler vs. non-seam bowler). Fifty-four female cricketers (professional seam bowler [n = 16]; professional non-seam bowler [n = 17]; non-professional seam bowler [n = 10]; non-professional non-seam bowler [n = 11]) undertook a battery of physical and anthropometric assessments during the off-season period. Participant's physical profile was assessed via the broad jump, countermovement jump, isometric mid-thigh pull (IMTP), 20 m sprint, run-2 cricket specific speed test, and Yo-Yo Intermittent Recovery Test Level-1 (Yo-Yo-IR1). The sum-of-eight skinfold measurement was also recorded for professional cricketers only. Differences between playing standard and position were assessed with a two-way ANOVA. Seam bowlers possessed a significantly (p < 0.04) greater stature and had a higher body mass than non-seam bowlers. Non-seam bowlers recorded significantly (p < 0.01) further broad jump, higher normalised peak vertical force during the IMTP, and ran greater distances during the Yo-Yo-IR1. Professional cricketers produced significantly further run distances for the Yo-Yo-IR1 and faster run-2 times for the dominant turning side than non-professional cricketers. This study provides valuable insights into the physical profile of female cricketers across playing standards and positions which practitioners can use to direct and enhance training outcomes.


Asunto(s)
Rendimiento Atlético , Críquet , Humanos , Femenino , Críquet/fisiología , Rendimiento Atlético/fisiología , Adulto , Adulto Joven , Carrera/fisiología , Atletas
2.
J Strength Cond Res ; 38(7): 1295-1299, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38900175

RESUMEN

ABSTRACT: Hill, V, Patterson, S, Buckthorpe, M, and Legg, HS. The acute effects of a preload upper-body power exercise on 50-m freestyle performance in youth swimmers. J Strength Cond Res 38(7): 1295-1299, 2024-This study aimed to investigate the acute effects of a medicine ball slam and the optimal recovery time required to induce a postactivation performance enhancement (PAPE) response on 50-meter freestyle swimming performance. Twenty-four (13 female, 11 male) competitive, adolescent swimmers (mean ± SD: age, 16.7 ± 1.2 years; height, 173.3 ± 6.7 cm; mass, 63.1 ± 6.4 kg) participated in a randomized crossover study. After the PAPE intervention (3 × 5 medicine ball slams), subjects had 1-minute, 4-minute, and 8-minute recovery periods before a 50-m maximal freestyle swim. A 1-way repeated-measures ANOVA revealed that different recovery times elicited changes in 50-m performance (F = 12.12, p < 0.0005). After 4 minutes of recovery, 50-m performance was 1.6% (0.47 seconds) faster (95% confidence interval [CI] [0.17-0.77], p < 0.001). When the data were split by sex, after 4 minutes of recovery, 50-m performance was 2% (0.64 seconds) faster for women (95% CI [0.279-0.998], p < 0.001). In conclusion, an upper-body power exercise, before performance, can induce a PAPE response and enhance 50-m freestyle performance after a 4-minute recovery period.


Asunto(s)
Rendimiento Atlético , Estudios Cruzados , Natación , Humanos , Natación/fisiología , Femenino , Adolescente , Masculino , Rendimiento Atlético/fisiología , Extremidad Superior/fisiología , Entrenamiento de Fuerza/métodos , Fuerza Muscular/fisiología
3.
J Hum Kinet ; 91(Spec Issue): 157-164, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38689581

RESUMEN

For the ischemic preconditioning (IPC) intervention, the accuracy of the protocol is paramount for mediating its possible ergogenic effects. However, the lack of standardization and widespread use of arbitrary cuff pressures (ranging from 130 to >300 mmHg) have been predominantly observed, potentially affecting the results and compromising the reproducibility of findings. Thus, the purpose of this study was to determine an appropriate cuff pressure during IPC. Seventeen healthy male participants were enrolled in the study. Anthropometric measurements were initially conducted, followed by systolic and diastolic blood pressure measurements. Subsequently, we determined the individual thigh occlusion pressure (TOP) for the right leg using a hand-held Doppler device. Based on these findings, we developed an estimation equation for TOP, considering the current brachial systolic blood pressure (SBP) values. We then conducted a retrospective analysis of its capacity to mediate occlusion. We observed the ability to estimate TOP using the equation (p = 0.01; ES: 0.86), presenting ~6% superiority in absolute values for occlusion compared to direct measurement (TOP equation: 169.9 ± 9.1; TOP direct measured: 161.2 ± 11.1). However, TOP estimation was insufficient to produce complete occlusion in two out of 17 subjects (11.8%). In conclusion, the estimation of TOP incorporating SBP values may offer a valid and practical means for cuff administration during IPC protocols with potential to minimize adverse effects and maximize its positive effects.

4.
Exp Physiol ; 109(5): 672-688, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38578259

RESUMEN

This study compared the acute hypoalgesic and neurophysiological responses to low-load resistance exercise with and without blood flow restriction (BFR), and free-flow, high-load exercise. Participants performed four experimental conditions where they completed baseline measures of pain pressure threshold (PPT), maximum voluntary force (MVF) with peripheral nerve stimulation to determine central and peripheral fatigue. Corticospinal excitability (CSE), corticospinal inhibition and short interval intracortical inhibition (SICI) were estimated with transcranial magnetic stimulation. Participants then performed low-load leg press exercise at 30% of one-repetition maximum (LL); low-load leg press with BFR at 40% (BFR40) or 80% (BFR80) of limb occlusion pressure; or high-load leg press of four sets of 10 repetitions at 70% one-repetition maximum (HL). Measurements were repeated at 5, 45 min and 24 h post-exercise. There were no differences in CSE or SICI between conditions (all P > 0.05); however, corticospinal inhibition was reduced to a greater extent (11%-14%) in all low-load conditions compared to HL (P < 0.005). PPTs were 12%-16% greater at 5 min post-exercise in BFR40, BFR80 and HL compared to LL (P ≤ 0.016). Neuromuscular fatigue displayed no clear difference in the magnitude or time course between conditions (all P > 0.05). In summary, low-load BFR resistance exercise does not induce different acute neurophysiological responses to low-load, free-flow exercise but it does promote a greater degree of hypoalgesia and reduces corticospinal inhibition more than high-load exercise, making it a useful rehabilitation tool. The changes in neurophysiology following exercise were not related to changes in PPT.


Asunto(s)
Umbral del Dolor , Flujo Sanguíneo Regional , Entrenamiento de Fuerza , Estimulación Magnética Transcraneal , Humanos , Masculino , Entrenamiento de Fuerza/métodos , Femenino , Adulto , Estimulación Magnética Transcraneal/métodos , Umbral del Dolor/fisiología , Adulto Joven , Flujo Sanguíneo Regional/fisiología , Ejercicio Físico/fisiología , Músculo Esquelético/fisiología , Fatiga Muscular/fisiología , Tractos Piramidales/fisiología , Potenciales Evocados Motores/fisiología
5.
Disaster Med Public Health Prep ; 18: e29, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38372077

RESUMEN

OBJECTIVE: The objective of this study was to describe changes in emergency department volumes after statewide lockdown in a network of hospitals across the United States during the COVID-19 global pandemic. METHODS: A retrospective study was performed utilizing data on daily volumes across multiple emergency departments from a centralized data warehouse from a private for-profit hospital system during the COVID-19 pandemic. The mean daily volumes of 148 emergency departments were evaluated across 16 states in relation to each state's governmental statewide lockdown orders. Comparisons of the same period in the prior year were evaluated for percent changes in volumes. We also compared pre-lockdown to post-lockdown volumes. A separate analysis was made for the pediatric ED volumes. RESULTS: The 2020 post-lockdown volumes compared to the same 2019 dates revealed a mean percent change of -43.09%. The overall post-lockdown volumes compared to the pre-lockdown volumes had a mean percent change of -45.00%. The pediatric data revealed a greater mean percentage change in volumes of -71.52% (post-lockdown compared to 2019) and -69.03% (post-lockdown compared to pre-lockdown). CONCLUSIONS: This study found an overall decrease in volumes among 148 emergency departments across 16 states when compared to the comparable period pre-global pandemic.


Asunto(s)
COVID-19 , Estados Unidos/epidemiología , Humanos , Niño , COVID-19/epidemiología , COVID-19/prevención & control , Control de Enfermedades Transmisibles , Pandemias/prevención & control , Estudios Retrospectivos , Servicio de Urgencia en Hospital
6.
J Strength Cond Res ; 38(3): 481-490, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38088873

RESUMEN

ABSTRACT: Scott, BR, Marston, KJ, Owens, J, Rolnick, N, and Patterson, SD. Current implementation and barriers to using blood flow restriction training: Insights from a survey of allied health practitioners. J Strength Cond Res 38(3): 481-490, 2024-This study investigated the use of blood flow restriction (BFR) exercise by practitioners working specifically with clinical or older populations, and the barriers preventing some practitioners from prescribing BFR. An online survey was disseminated globally to allied health practitioners, with data from 397 responders included in analyses. Responders who had prescribed BFR exercise ( n = 308) completed questions about how they implement this technique. Those who had not prescribed BFR exercise ( n = 89) provided information on barriers to using this technique, and a subset of these responders ( n = 22) completed a follow-up survey to investigate how these barriers could be alleviated. Most practitioners prescribe BFR exercise for musculoskeletal rehabilitation clients (91.6%), with the BFR cuff pressure typically relative to arterial occlusion pressure (81.1%) and implemented with resistance (96.8%) or aerobic exercise (42.9%). Most practitioners screen for contraindications (68.2%), although minor side effects, including muscle soreness (65.8%), are common. The main barriers preventing some practitioners from using BFR are lack of equipment (60.2%), insufficient education (55.7%), and safety concerns (31.8%). Suggestions to alleviate these barriers included developing educational resources about the safe application and benefits of BFR exercise ( n = 20) that are affordable ( n = 3) and convenient ( n = 4). These results indicate that BFR prescription for clinical and older cohorts mainly conforms with current guidelines, which is important considering the potentially increased risk for adverse events in these cohorts. However, barriers still prevent broader utility of BFR training, although some may be alleviated through well-developed educational offerings to train practitioners in using BFR exercise.


Asunto(s)
Músculo Esquelético , Entrenamiento de Fuerza , Humanos , Músculo Esquelético/fisiología , Terapia de Restricción del Flujo Sanguíneo , Entrenamiento de Fuerza/métodos , Mialgia , Ejercicio Físico/fisiología , Flujo Sanguíneo Regional/fisiología , Fuerza Muscular/fisiología
7.
Sports Med ; 54(1): 49-72, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37787846

RESUMEN

Outcomes following anterior cruciate ligament reconstruction (ACLR) need improving, with poor return-to-sport rates and a high risk of secondary re-injury. There is a need to improve rehabilitation strategies post-ACLR, if we can support enhanced patient outcomes. This paper discusses how to optimise the early-stage rehabilitation process post-ACLR. Early-stage rehabilitation is the vital foundation on which successful rehabilitation post-ACLR can occur. Without high-quality early-stage (and pre-operative) rehabilitation, patients often do not overcome major aspects of dysfunction, which limits knee function and the ability to transition through subsequent stages of rehabilitation optimally. We highlight six main dimensions during the early stage: (1) pain and swelling; (2) knee joint range of motion; (3) arthrogenic muscle inhibition and muscle strength; (4) movement quality/neuromuscular control during activities of daily living (5) psycho-social-cultural and environmental factors and (6) physical fitness preservation. The six do not share equal importance and the extent of time commitment devoted to each will depend on the individual patient. The paper provides recommendations on how to implement these into practice, discussing training planning and programming, and suggests specific screening to monitor work and when the athlete can progress to the next stage (e.g. mid-stage rehabilitation entry criteria).


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Humanos , Actividades Cotidianas , Articulación de la Rodilla , Volver al Deporte , Atletas
8.
Eur J Sport Sci ; 23(12): 2435-2442, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37746841

RESUMEN

Ischaemic preconditioning (IPC) applied locally and remotely has been shown to reduce pain which may underpin its ergogenic effect on exercise performance, however, it is unclear how many IPC cycles are needed to induce hypoalgesia. Therefore the purpose of this study was to examine the number of cycles of IPC on experimental pain perception. Sixteen healthy participants underwent four, randomised, experimental sessions where they either underwent a sham protocol (1 × 5 min at 20 mmHg), and 1, 2 or 3 cycles × 5 min of remote IPC at 105% of limb occlusion pressure. Ten minutes post-intervention, participants underwent a cold-pressor test where pain threshold, pain tolerance and pain intensity were examined and compared between conditions with a one-way repeated measure analysis of variance. Pain threshold was not different between conditions (P = 0.065); but pain tolerance was increased by ∼30% in the 1 × 5 condition, 2 × 5 condition, and 3 × 5 condition compared to the sham condition. No differences in pain tolerance were seen between the different numbers of cycles (all P > 0.05). There was also no difference in the perception of pain 30 s into the cold pressor test (P = 0.279). Remote IPC appears to significantly improve tolerance to pain which may have significant implications for endurance performance and exercise rehabilitation, but this warrants further investigation.


We found that one, two or three cycles of ischaemic preconditioning improved cold pain tolerance by 30% compared to a sham protocol, but there was no clear effect of IPC on pain threshold or pain intensity.The pain reported during IPC decreased from cycle one to cycle three in the three cycle condition, suggesting a potential conditioned pain modulation effect.An increase in pain tolerance may explain why IPC can improve exercise performance and IPC itself could be used as a tool to improve tolerance to pain.


Asunto(s)
Precondicionamiento Isquémico , Humanos , Precondicionamiento Isquémico/métodos , Ejercicio Físico , Dolor , Terapia por Ejercicio , Extremidades
9.
J Strength Cond Res ; 37(10): 2106-2117, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37639646

RESUMEN

ABSTRACT: Femoroacetabular impingement (FAI) in ice hockey is a concern for many athletes. The biomechanics of skating and the injury mechanism, prevalence, identification, and treatment protocols currently available for FAI in ice hockey athletes are important for all coaches and practitioners to understand. This article discusses the underlying anatomical issues and biomechanical considerations surrounding FAI. Furthermore, this article describes the interventions that can be used when encountering FAI and well-established protocols to aid in the return to play. Finally, prevention strategies that can aid in injury prevention are discussed.


Asunto(s)
Pinzamiento Femoroacetabular , Hockey , Patinación , Humanos , Pinzamiento Femoroacetabular/diagnóstico por imagen , Pinzamiento Femoroacetabular/etiología , Atletas , Fenómenos Biomecánicos
11.
J Med Chem ; 66(13): 8896-8916, 2023 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-37343180

RESUMEN

While treatment options for human African trypanosomiasis (HAT) have improved significantly, there is still a need for new drugs with eradication now a realistic possibility. Here, we report the development of 2,4-diaminothiazoles that demonstrate significant potency against Trypanosoma brucei, the causative agent of HAT. Using phenotypic screening to guide structure-activity relationships, potent drug-like inhibitors were developed. Proof of concept was established in an animal model of the hemolymphatic stage of HAT. To treat the meningoencephalitic stage of infection, compounds were optimized for pharmacokinetic properties, including blood-brain barrier penetration. However, in vivo efficacy was not achieved, in part due to compounds evolving from a cytocidal to a cytostatic mechanism of action. Subsequent studies identified a nonessential kinase involved in the inositol biosynthesis pathway as the molecular target of these cytostatic compounds. These studies highlight the need for cytocidal drugs for the treatment of HAT and the importance of static-cidal screening of analogues.


Asunto(s)
Citostáticos , Tripanocidas , Trypanosoma brucei brucei , Tripanosomiasis Africana , Animales , Humanos , Tripanosomiasis Africana/tratamiento farmacológico , Tripanocidas/uso terapéutico , Tripanocidas/farmacocinética , Citostáticos/uso terapéutico , Barrera Hematoencefálica
12.
STAR Protoc ; 4(1): 102002, 2023 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-36609153

RESUMEN

Here, we provide a protocol using chemical pulldown combined with mass spectrometry (LC-MS/MS) to identify drug targets in Plasmodium falciparum. This approach works upon the principle that a resin-bound inhibitor selectively binds its molecular target(s) in cell-free lysates. We describe the preparation of drug beads and P. falciparum lysate, followed by chemical pulldown, sample fractionation, and LC-MS/MS analysis. We then detail how to identify specifically bound proteins by comparing protein enrichment in DMSO-treated relative to drug-treated lysates via quantitative proteomics. For complete details on the use and execution of this protocol, please refer to Milne et al. (2022).1.


Asunto(s)
Antimaláricos , Cromatografía Liquida/métodos , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Antimaláricos/metabolismo , Espectrometría de Masas en Tándem/métodos , Proteínas/metabolismo , Plasmodium falciparum
13.
Eur J Sport Sci ; 23(9): 1849-1858, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36336974

RESUMEN

This study investigated whether anthropometric and physical abilities explained variance in match collision performance among international female rugby union players. Physical performance and anthropometric data for fifty-one international female rugby union players, and collision actions categorised as "effort" or "performance" variables, from 20 international matches, were analysed using partial least squares regression. Among forwards, variance in carries/min was explained (R2 = .22) by a combination of; body mass, skinfolds, acceleration momentum and negative associations with mean aerobic speed and single-leg isometric squat relative force (SLISO/kgBM). Variance in collision dominance among forwards was explained (R2 = .21) by lower skinfolds and higher acceleration momentum, while tackles/min (R2 = .19) were explained by greater jumping power and single-leg isometric squat (SLISO). Among backs, variance in tackles/min (R2 = .54) was explained by greater bench press, SLISO and SLISO/kgBM. Variance in collision dominance among backs was explained (R2 = .23) by negative and positive associations with body mass and SLISO/kgBM, respectively. These findings suggest the development of physical characteristics, such as body mass and composition, strength and power contribute towards successful collision actions among international female rugby union players. The contribution of different physical characteristics towards collision events is dependent on position, and whether the collision event is categorised by "performance" or "effort". It is suggested that physical training programmes should reflect this level of specificity.HighlightsAmong elite female rugby union forwards, acceleration momentum, body mass and skinfolds are positively associated with winning collisions and carrying the ball into contact more frequently, whilst tackle frequency is positively associated with relative leg strength and power output.Among elite female backs, the ability to win collisions is positively associated with relative leg power output, and negatively associated with body mass. Tackle frequency is associated with maximum upper- and lower-body strength in this group.Physical characteristics account for some of the variability in collision performance, but interpretation of these findings should consider that factors such as technique during collision events may account for a larger proportion of total variance.Sports science practitioners can improve collision performance, to varying degrees, by enhancing specific gross physical characteristics, according to a player's position and the tactical role they are expected to fulfil.


Asunto(s)
Rendimiento Atlético , Fútbol Americano , Humanos , Femenino , Rugby , Aptitud Física , Antropometría , Fuerza Muscular
14.
J Strength Cond Res ; 36(10): 2696-2700, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36135029

RESUMEN

ABSTRACT: Lovegrove, S, Hughes, L, Mansfield, S, Read, P, Price, P, and Patterson, SD. Repetitions in reserve is a reliable tool for prescribing resistance training load. J Strength Cond Res 36(10): 2696-2700, 2022-This study investigated the reliability of repetitions in reserve (RIR) as a method for prescribing resistance training load for the deadlift and bench press exercises. Fifteen novice trained men (age: 17.3 ± 0.9 years, height: 176.0 ± 8.8 cm, body mass: 71.3 ± 10.7 kg) were assessed for 1 repetition maximum (1RM) for deadlift (118.1 ± 27.3 kg) and bench press (58.2 ± 18.6 kg). Subsequently, they completed 3 identical sessions (one familiarization session and 2 testing sessions) comprising sets of 3, 5, and 8 repetitions. For each repetition scheme, the load was progressively increased in successive sets until subjects felt they reached 1-RIR at the end of the set. Test-retest reliability of load prescription between the 2 testing sessions was determined using intraclass correlation coefficient (ICC) and coefficient of variation (CV). A 2-way analysis of variance with repeated measures was used for each exercise to assess differences in the load corresponding to 1-RIR within each repetition scheme. All test-retest comparisons demonstrated a high level of reliability (deadlift: ICC = 0.95-0.99, CV = 2.7-5.7% and bench press: ICC = 0.97-0.99, CV = 3.8-6.2%). Although there were no differences between time points, there was a difference for load corresponding to 1-RIR across the 3 repetition schemes (deadlift: 88.2, 84.3, and 79.2% 1RM; bench press: 93.0, 87.3, and 79.6% 1RM for the 3-, 5-, and 8-repetition sets, respectively). These results suggest that RIR is a reliable tool for load prescription in a young novice population. Furthermore, the between-repetition scheme differences highlight that practitioners can effectively manipulate load and volume (repetitions in a set) throughout a training program to target specific resistance training adaptations.


Asunto(s)
Entrenamiento de Fuerza , Adolescente , Prueba de Esfuerzo , Humanos , Masculino , Fuerza Muscular , Reproducibilidad de los Resultados , Entrenamiento de Fuerza/métodos , Levantamiento de Peso
15.
ACS Infect Dis ; 8(9): 1962-1974, 2022 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-36037410

RESUMEN

There is a pressing need for new medicines to prevent and treat malaria. Most antimalarial drug discovery is reliant upon phenotypic screening. However, with the development of improved target validation strategies, target-focused approaches are now being utilized. Here, we describe the development of a toolkit to support the therapeutic exploitation of a promising target, lysyl tRNA synthetase (PfKRS). The toolkit includes resistant mutants to probe resistance mechanisms and on-target engagement for specific chemotypes; a hybrid KRS protein capable of producing crystals suitable for ligand soaking, thus providing high-resolution structural information to guide compound optimization; chemical probes to facilitate pulldown studies aimed at revealing the full range of specifically interacting proteins and thermal proteome profiling (TPP); as well as streamlined isothermal TPP methods to provide unbiased confirmation of on-target engagement within a biologically relevant milieu. This combination of tools and methodologies acts as a template for the development of future target-enabling packages.


Asunto(s)
Antimaláricos , Lisina-ARNt Ligasa , Malaria , Antimaláricos/química , Antimaláricos/farmacología , Descubrimiento de Drogas , Humanos , Lisina-ARNt Ligasa/química , Lisina-ARNt Ligasa/genética , Lisina-ARNt Ligasa/metabolismo , Plasmodium falciparum/metabolismo
16.
J Clin Med ; 11(14)2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35887701

RESUMEN

Muscle wasting is implicated in the pathogenesis of intensive care unit acquired weakness (ICU-AW), affecting 40% of patients and causing long-term physical disability. A repetitive vascular occlusion stimulus (RVOS) limits muscle atrophy in healthy and orthopaedic subjects, thus, we explored its application to ICU patients. Adult multi-organ failure patients received standard care +/- twice daily RVOS {4 cycles of 5 min tourniquet inflation to 50 mmHg supra-systolic blood pressure, and 5 min complete deflation} for 10 days. Serious adverse events (SAEs), tolerability, feasibility, acceptability, and exploratory outcomes of the rectus femoris cross-sectional area (RFCSA), echogenicity, clinical outcomes, and blood biomarkers were assessed. Only 12 of the intended 32 participants were recruited. RVOS sessions (76.1%) were delivered to five participants and two could not tolerate it. No SAEs occurred; 75% of participants and 82% of clinical staff strongly agreed or agreed that RVOS is an acceptable treatment. RFCSA fell significantly and echogenicity increased in controls (n = 5) and intervention subjects (n = 4). The intervention group was associated with less frequent acute kidney injury (AKI), a greater decrease in the total sequential organ failure assessment score (SOFA) score, and increased insulin-like growth factor-1 (IGF-1), and reduced syndecan-1, interleukin-4 (IL-4) and Tumor necrosis factor receptor type II (TNF-RII) levels. RVOS application appears safe and acceptable, but protocol modifications are required to improve tolerability and recruitment. There were signals of possible clinical benefit relating to RVOS application.

17.
Int J Sports Physiol Perform ; 17(9): 1425-1431, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35894997

RESUMEN

PURPOSE: To examine the effect of fast- versus slow-speed eccentric-muscle-action resistance training on lower-body strength, vertical jump height, sprint speed, and change-of-direction performance in elite soccer players during a competitive season. METHODS: Twenty-two elite soccer players, from a single team, were randomly assigned to groups that undertook either 1- (fast speed) or 4-second (slow speed) eccentric resistance training during the in-season period. A 5-week program was conducted during an elite top-division European League soccer season. Performance measures including predicted 1-repetition-maximum back squat, countermovement jump, 20-m sprint, and change of direction were tested before and after the intervention period. Total match and training running distance and muscle soreness were also recorded during each week of the intervention. RESULTS: An analysis of covariance showed significant group effects (P = .01) for countermovement jump with a greater jump height in the 1-second fast-speed group postintervention (95% CI, 1.1-6.9 cm). Despite an overall increase in 1-repetition maximum pretraining to posttraining (95% CI, 10.0-15.3 kg, effect size 0.69), there were no significant differences (P > .05) between groups after the intervention. Similarly, there were no differences between groups for change of direction, 20-m sprint, or muscle soreness. CONCLUSION: Faster eccentric muscle actions may be superior for increasing movements in elite soccer players in-season.


Asunto(s)
Rendimiento Atlético , Entrenamiento de Fuerza , Carrera , Fútbol , Rendimiento Atlético/fisiología , Humanos , Fuerza Muscular/fisiología , Músculos , Mialgia , Carrera/fisiología , Estaciones del Año , Fútbol/fisiología
18.
Eur J Appl Physiol ; 122(8): 1797-1810, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35362800

RESUMEN

Heat-induced hypo-hydration (hyperosmotic hypovolemia) can reduce prolonged skeletal muscle performance; however, the mechanisms are less well understood and the reported effects on all aspects of neuromuscular function and brief maximal contractions are inconsistent. Historically, a 4-6% reduction of body mass has not been considered to impair muscle function in humans, as determined by muscle torque, membrane excitability and peak power production. With the development of magnetic resonance imaging and neurophysiological techniques, such as electromyography, peripheral nerve, and transcranial magnetic stimulation (TMS), the integrity of the brain-to-muscle pathway can be further investigated. The findings of this review demonstrate that heat-induced hypo-hydration impairs neuromuscular function, particularly during repeated and sustained contractions. Additionally, the mechanisms are separate to those of hyperthermia-induced fatigue and are likely a result of modulations to corticospinal inhibition, increased fibre conduction velocity, pain perception and impaired contractile function. This review also sheds light on the view that hypo-hydration has 'no effect' on neuromuscular function during brief maximal voluntary contractions. It is hypothesised that irrespective of unchanged force, compensatory reductions in cortical inhibition are likely to occur, in the attempt of achieving adequate force production. Studies using single-pulse TMS have shown that hypo-hydration can reduce maximal isometric and eccentric force, despite a reduction in cortical inhibition, but the cause of this is currently unclear. Future work should investigate the intracortical inhibitory and excitatory pathways within the brain, to elucidate the role of the central nervous system in force output, following heat-induced hypo-hydration.


Asunto(s)
Potenciales Evocados Motores , Contracción Isométrica , Estimulación Eléctrica/métodos , Electromiografía/métodos , Potenciales Evocados Motores/fisiología , Calor , Humanos , Contracción Isométrica/fisiología , Contracción Muscular/fisiología , Fatiga Muscular/fisiología , Músculo Esquelético/fisiología , Estimulación Magnética Transcraneal
19.
J Med Chem ; 65(7): 5606-5624, 2022 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-35303411

RESUMEN

African animal trypanosomiasis or nagana, caused principally by infection of the protozoan parasites Trypanosoma congolense and Trypanosoma vivax, is a major problem in cattle and other livestocks in sub-Saharan Africa. Current treatments are threatened by the emergence of drug resistance and there is an urgent need for new, effective drugs. Here, we report the repositioning of a compound series initially developed for the treatment of human African trypanosomiasis. A medicinal chemistry program, focused on deriving more soluble analogues, led to development of a lead compound capable of curing cattle infected with both T. congolense and T. vivax via intravenous dosing. Further optimization has the potential to yield a single-dose intramuscular treatment for this disease. Comprehensive mode of action studies revealed that the molecular target of this promising compound and related analogues is the cyclin-dependent kinase CRK12.


Asunto(s)
Trypanosoma congolense , Tripanosomiasis Africana , Animales , Bovinos , Quinasas Ciclina-Dependientes , Reposicionamiento de Medicamentos , Trypanosoma vivax , Tripanosomiasis Africana/tratamiento farmacológico , Tripanosomiasis Africana/parasitología , Tripanosomiasis Africana/veterinaria
20.
Clin J Sport Med ; 32(6): 580-587, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-35325898

RESUMEN

OBJECTIVE: There is a high incidence of concussion and frequent utilization of rapid weight loss (RWL) methods among combat sport athletes, yet the apparent similarity in symptoms experienced as a result of a concussion or RWL has not been investigated. This study surveyed combat sports athletes to investigate the differences in symptom onset and recovery between combat sports and evaluated the relationships between concussion and RWL symptoms. DESIGN: Cross-sectional study. SETTING: Data were collected through an online survey. PARTICIPANTS: One hundred thirty-two (115 male athletes and 17 female athletes) combat sport athletes. INTERVENTIONS: Modified Sport Concussion Assessment Tool (SCAT) symptom checklist and weight-cutting questionnaire. MAIN OUTCOME MEASURES: Survey items included combat sport discipline, weight loss, medical history, weight-cutting questionnaire, and concussion and weight-cutting symptom checklists. RESULTS: Strong associations ( rs = 0.6-0.7, P < 0.05) were observed between concussion and RWL symptoms. The most frequently reported symptom resolution times were 24 to 48 hours for a weight cut (WC; 59%) and 3 to 5 days for a concussion (43%), with 60% to 70% of athletes reporting a deterioration and lengthening of concussion symptoms when undergoing a WC. Most of the athletes (65%) also reported at least one WC in their career to " not go according to plan ," resulting in a lack of energy (83%) and strength/power (70%). CONCLUSIONS: Rapid weight loss and concussion symptoms are strongly associated, with most of the athletes reporting a deterioration of concussion symptoms during a WC. The results indicate that concussion symptoms should be monitored alongside hydration status to avoid any compound effects of prior RWL on the interpretation of concussion assessments and to avoid potential misdiagnoses among combat athletes.


Asunto(s)
Traumatismos en Atletas , Conmoción Encefálica , Masculino , Femenino , Humanos , Estudios Transversales , Conmoción Encefálica/diagnóstico , Conmoción Encefálica/etiología , Atletas , Pérdida de Peso , Encuestas y Cuestionarios , Traumatismos en Atletas/diagnóstico , Traumatismos en Atletas/complicaciones
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