Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
1.
J Occup Environ Med ; 65(12): e785-e790, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37757773

RESUMEN

OBJECTIVE: For a cohort of operational firefighters, we assessed the effects of workplace-based high-intensity interval training (HIIT) on cardiorespiratory fitness. METHODS: Fifteen firefighters performed HIIT or moderate-intensity continuous training for 4 weeks. Outcomes were peak oxygen uptake, time trial performance, and affective (pleasure/displeasure) responses to exercise. RESULTS: There was an increase in peak oxygen uptake for both conditions, although this did not reach statistical significance ( P = 0.06, η2 = 0.26) and time trial performance improved for both groups (2%, P < 0.01, η2 = 0.51). Affective responses were more favorable for HIIT, but both conditions avoided excessive sensations of displeasure. CONCLUSION: Results suggest that workplace-based HIIT improved fitness and performance to a similar magnitude to moderate-intensity continuous training while avoiding overly negative affective responses and could improve occupational health of firefighters, despite reduced time commitment.


Asunto(s)
Capacidad Cardiovascular , Bomberos , Entrenamiento de Intervalos de Alta Intensidad , Humanos , Ejercicio Físico/fisiología , Entrenamiento de Intervalos de Alta Intensidad/métodos , Oxígeno
2.
Respir Res ; 24(1): 150, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37268935

RESUMEN

BACKGROUND: Although currently most widely used in mechanical ventilation and cardiopulmonary resuscitation, features of the carbon dioxide (CO2) waveform produced through capnometry have been shown to correlate with V/Q mismatch, dead space volume, type of breathing pattern, and small airway obstruction. This study applied feature engineering and machine learning techniques to capnography data collected by the N-Tidal™ device across four clinical studies to build a classifier that could distinguish CO2 recordings (capnograms) of patients with COPD from those without COPD. METHODS: Capnography data from four longitudinal observational studies (CBRS, GBRS, CBRS2 and ABRS) was analysed from 295 patients, generating a total of 88,186 capnograms. CO2 sensor data was processed using TidalSense's regulated cloud platform, performing real-time geometric analysis on CO2 waveforms to generate 82 physiologic features per capnogram. These features were used to train machine learning classifiers to discriminate COPD from 'non-COPD' (a group that included healthy participants and those with other cardiorespiratory conditions); model performance was validated on independent test sets. RESULTS: The best machine learning model (XGBoost) performance provided a class-balanced AUROC of 0.985 ± 0.013, positive predictive value (PPV) of 0.914 ± 0.039 and sensitivity of 0.915 ± 0.066 for a diagnosis of COPD. The waveform features that are most important for driving classification are related to the alpha angle and expiratory plateau regions. These features correlated with spirometry readings, supporting their proposed properties as markers of COPD. CONCLUSION: The N-Tidal™ device can be used to accurately diagnose COPD in near-real-time, lending support to future use in a clinical setting. TRIAL REGISTRATION: Please see NCT03615365, NCT02814253, NCT04504838 and NCT03356288.


Asunto(s)
Dióxido de Carbono , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Capnografía/métodos , Volumen Espiratorio Forzado , Capacidad Vital
3.
Sci Med Footb ; : 1-8, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37347551

RESUMEN

The physical demands of elite sport are often monitored with the aim of making evidence-based decisions to enhance performance and reduce injury risk. However, there is limited evidence in rugby league of the monitoring practices and perspectives of practitioners. This study provides a cross-sectional view of practices and perspectives of rugby league practitioners engaged in monitoring the physical demands of training. Practitioners from the Super League, Championship and National Rugby League competitions completed an online survey. Questions related to the tools and measures used to monitor training, along with perceptions of monitoring effectiveness. 'Enhancing performance' was considered the most important factor for monitoring training demands with most practitioners using some form of time motion analysis (e.g., GPS) or accelerometers. Nearly all practitioners combined objective external measures of exercise intensity with subjective measures, of which RPE was most common. The monitoring parameters considered most useful were running metrics (high-speed running, total distance covered, and the number of accelerations). Findings suggest that current practices are mostly supported by evidence from research. There was a preference for internal load monitoring tools that are quick and simple, such as RPE. The extent to which training load was monitored was lesser in some Championship teams compared to those in the other competitions, which might be explained by discrepancies in funding and access to players.

4.
Res Q Exerc Sport ; 94(1): 237-245, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35344470

RESUMEN

Purpose: The extra-time (ET) period of soccer is competed during fixture congested schedules with often limited recovery time between matches. The aim of this study was to assess muscle damage recovery following 90- and 120-min (i.e., incorporation of ET) of simulated soccer match-play. Methods: Twelve semiprofessional soccer players completed 90 and 120-min treadmill-based soccer-specific exercise in a counterbalanced order. Creatine kinase (CK), creatinine, urea, aspartate aminotransferase, perceived muscle soreness, pain pressure threshold, reactive strength index, countermovement jump height, and isokinetic strength assessments of eccentric knee flexors at 60, 180 and 270 deg‧s-1 were taken at baseline and immediately-, 24, 48 and 72-hr post-exercise to assess recovery. Results: No significant between-trial interactions except for CK were found. Pairwise comparisons detected a 53% increase in CK at 24-hr (455 ± 29 µâˆ™L-1) following 120-min of simulated match-play vs. the corresponding post 90-min time-point (299 ± 29 µâˆ™L-1; p < .01). The 120-min trial caused a 58% higher CK response at 72-hr (244 ± 25 µâˆ™L-1) vs. post 90-min comparisons (154 ± 29 µâˆ™L-1; p = .02). No interaction effects were detected for any other recovery variables. Creatine kinase and perceived muscle soreness remained elevated up to 72-hr in both trials (p < .01). Conclusions: These data indicate that 120 min of simulated soccer match-play delays the time-course of CK recovery up to 72-hr post-match. However, 120 min of simulated soccer has no additional impact on functional recovery and perceived muscle soreness vs. 90 min. Recovery should be investigated following 90- and 120-min of actual match-play.Trial registration The study was pre-registered on the Open Science Framework (DOI: 10.17605/OSF.IO/VGU6T Date: 10/06/2019).


Asunto(s)
Rendimiento Atlético , Fútbol , Humanos , Fútbol/fisiología , Mialgia , Ejercicio Físico/fisiología , Prueba de Esfuerzo , Creatina Quinasa , Rendimiento Atlético/fisiología
5.
Synth Biol (Oxf) ; 7(1): ysac023, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36381610

RESUMEN

Standardized deoxyribonucleic acid (DNA) assembly methods utilizing modular components provide a powerful framework to explore designs and iterate through Design-Build-Test-Learn cycles. Biopart Assembly Standard for Idempotent Cloning (BASIC) DNA assembly uses modular parts and linkers, is highly accurate, easy to automate, free for academic and commercial use and enables hierarchical assemblies through an idempotent format. These features enable applications including pathway engineering, ribosome binding site (RBS) tuning, fusion protein engineering and multiplexed guide ribonucleic acid (RNA) expression. In this work, we present basicsynbio, open-source software encompassing a Web App (https://basicsynbio.web.app/) and Python Package (https://github.com/LondonBiofoundry/basicsynbio), enabling BASIC construct design via simple drag-and-drop operations or programmatically. With basicsynbio, users can access commonly used BASIC parts and linkers while designing new parts and assemblies with exception handling for common errors. Users can export sequence data and create instructions for manual or acoustic liquid-handling platforms. Instruction generation relies on the BasicBuild Open Standard, which is parsed for bespoke workflows and is serializable in JavaScript Object Notation for transfer and storage. We demonstrate basicsynbio, assembling 30 vectors using sequences including modules from the Standard European Vector Architecture (SEVA). The BASIC SEVA vector collection is compatible with BASIC and Golden Gate using BsaI. Vectors contain one of six antibiotic resistance markers and five origins of replication from different compatibility groups. The collection is available via Addgene under an OpenMTA agreement. Furthermore, vector sequences are available from within the basicsynbio application programming interface with other collections of parts and linkers, providing a powerful environment for designing assemblies for bioengineering applications. Graphical Abstract.

6.
Biol Sport ; 39(1): 171-179, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35173375

RESUMEN

Research has demonstrated that the extra-time (ET) period of soccer negatively impacts recovery. However, it is not known to what extent recovery practices are being adapted by practitioners following ET and where gaps exist between research and practice. Therefore, this study explored soccer practitioner perceptions of recovery practices following ET matches. A total of 72 practitioners from across different levels of soccer and several countries completed a bespoke online survey. Inductive content analysis of the responses identified five higher-order themes: 'conditioning', 'player monitoring', 'recovery practices', 'training', and 'future research directions'. Mixed responses were received in relation to whether practitioners condition players in preparation for ET, though 72% allowed players to return to training based on fatigue markers following this additional 30-min period. Sixty-three (88%) practitioners believed that ET delays the time-course of recovery, with 82% highlighting that practices should be adapted following ET compared with a typical 90-min match. Forty-nine practitioners (68%) reduce training loads and intensities for up to 48 hr post ET matches, though training mostly recommences as 'normal' at 72 hr. Sixty-three (88%) practitioners believed that more research should be conducted on recovery following ET, with 'tracking players physiological and physical responses', 'nutritional interventions to accelerate recovery' and 'changes in acute injury-risk' being the three areas of research that practitioners ranked as most important. These data suggest practitioners and coaches adjust recovery practices following ET matches compared to 90 min. Further research on the efficacy of recovery strategies following ET matches is required to inform applied practice.

7.
J Sport Health Sci ; 11(3): 403-414, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-32445903

RESUMEN

OBJECTIVE: Soccer match-play is typically contested over 90 min; however, in some cup and tournament scenarios, when matches are tied, they proceed to an additional 30 min, which is termed "extra-time" (ET). This systematic review sought to appraise the literature available on 120-min of soccer-specific exercise, with a view to identifying practical recommendations and future research opportunities. METHODS: The review was conducted according to the PRISMA guidelines. Independent researchers performed a systematic search of PubMed, CINAHL, and PsycINFO in May 2019, with the following keywords entered in various combinations: "soccer", "football", "extra-time", "extra time", "extratime", "120 minutes", "120 min", "additional 30 minutes", and "additional 30 min". RESULTS: The search yielded an initial 73 articles. Following the screening process, 11 articles were accepted for analyses. Articles were subsequently organized into the following 5 categories: movement demands of ET, performance responses to ET, physiological and neuromuscular response during ET, nutritional interventions, and recovery and ET. The results highlighted that during competitive match-play, players cover 5%-12% less distance relative to match duration (i.e., meters per minute) during ET compared to the preceding 90 min. Reductions in technical performance (i.e., shot speed, number of passes and dribbles) were also observed during ET. Additionally, carbohydrate provision may attenuate and improve dribbling performance during ET. Moreover, objective and subjective measures of recovery may be further compromised following ET when compared to 90 min. CONCLUSION: Additional investigations are warranted to further substantiate these findings and identify interventions to improve performance during ET.


Asunto(s)
Rendimiento Atlético , Fútbol , Rendimiento Atlético/fisiología , Movimiento , Fútbol/fisiología , Humanos
8.
Res Q Exerc Sport ; 93(2): 368-378, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-33306941

RESUMEN

Purpose: The aim of this study was to investigate thigh musculature excitation and torque generation in response to soccer-specific exercise incorporating an extra-time (ET) period. Methods: Twelve semiprofessional soccer players performed 120-min treadmill-based soccer-specific exercise. Surface electromyography (EMG) signals for the rectus femoris (EMGRF) and biceps femoris (EMGBF) were measured as the mean response across a pre-determined 10-second sprint bout during each 15-min block of exercise. Peak eccentric torque of the knee flexors (eccKF) and concentric torque of the knee extensors (conKE) were recorded across angular velocities of 60, 180, and 270 deg∙s-1 immediately pre- and post-exercise. Tri-axial PlayerLoad™ (PL-T) was monitored throughout exercise and defined across vertical (PL-V), anterior-posterior (PL-AP), and medial-lateral (PL-ML) planes of motion. Results: A reduction in normalized EMGRF amplitude was evident at 105‒120 min, versus 0‒15 min (-12.5%; p = .037), 15‒30 min (-12.5%; p = .047), and 45‒60 min (-14%; p = .030). Peak torque of the eccKF was significantly reduced from pre- to post-exercise at 60 (-7.7%; p = .018), 180 (-10.5%; p = .042), and 270 deg∙s-1 (-7.5%; p = .034). A main effect for time was identified for PL-T (p < .010), PL-V (p = .033), and PL-AP (p < .010). Conclusions: These findings suggest that muscle excitation of the rectus femoris is reduced during ET, accompanied with a deficit in the torque generation of the knee flexors following 120 min of soccer-specific activity. Practitioners should adequately condition players for the additional ET period by incorporating exercises into training schedules that develop fatigue-resistant eccentric hamstring strength to minimize injury risk.


Asunto(s)
Músculos Isquiosurales , Fútbol , Músculos Isquiosurales/fisiología , Humanos , Fatiga Muscular/fisiología , Fuerza Muscular , Músculo Esquelético/fisiología , Fútbol/fisiología , Torque
9.
Clin Obes ; 11(3): e12444, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33600056

RESUMEN

Obesity continues to be a global health problem with significant costs associated with management, treatment, and obesity-related comorbidities. Tier 3 weight management programmes support patients with complex obesity and traditionally offer interventions through face-to-face delivery. In this study, a service evaluation compared weight loss for adults with a BMI ≥ 45 kg/m2 or ≥ 40 kg/m2 with a comorbidity, who were offered a non-randomized dietetic intervention through face-to-face, telephone, or digital support using the Oviva smartphone app as part of a tier 3 weight management programme. One hundred and sixty-nine patients commenced the core programme. There were no significant differences in weight loss between patients receiving face-to-face (5.3 ± 5.5 kg [-4.1%]), telephone (-4 ± 5.3 kg [-3.4%]) and digital support (-6.1 ± 4.9 kg [-4.5%]) (P = .061), with data reported as intention-to-treat using baseline observation carried forward imputation. Completer data were also analysed at an optional 12-week follow-up where weight loss was maintained with no significant differences between face-to-face (-7.6 ± 9.3 kg [-5.6%]) and digital support (-9.2 ± 7.6) kg [-6.8%]) (P = .135). Furthermore, there were no significant differences in the acceptability of the interventions (P = .261). Due to the potential scalability, resource, and cost-savings of digital care, and improvement in accessibility for some people, digital delivery of weight management programmes should be considered as a care option in weight management services.


Asunto(s)
Dietética , Programas de Reducción de Peso , Redes de Comunicación de Computadores , Humanos , Obesidad/terapia , Teléfono , Pérdida de Peso
10.
Metab Eng ; 63: 81-101, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33301873

RESUMEN

Synthetic Biology is a rapidly growing interdisciplinary field that is primarily built upon foundational advances in molecular biology combined with engineering design principles such as modularity and interoperability. The field considers living systems as programmable at the genetic level and has been defined by the development of new platform technologies and methodological advances. A key concept driving the field is the Design-Build-Test-Learn cycle which provides a systematic framework for building new biological systems. One major application area for synthetic biology is biosynthetic pathway engineering that requires the modular assembly of different genetic regulatory elements and biosynthetic enzymes. In this review we provide an overview of modular DNA assembly and describe and compare the plethora of in vitro and in vivo assembly methods for combinatorial pathway engineering. Considerations for part design and methods for enzyme balancing are also presented, and we briefly discuss alternatives to intracellular pathway assembly including microbial consortia and cell-free systems for biosynthesis. Finally, we describe computational tools and automation for pathway design and assembly and argue that a deeper understanding of the many different variables of genetic design, pathway regulation and cellular metabolism will allow more predictive pathway design and engineering.


Asunto(s)
Redes y Vías Metabólicas , Biología Sintética , Vías Biosintéticas , Sistema Libre de Células , ADN , Ingeniería Metabólica , Redes y Vías Metabólicas/genética
11.
Int J Sports Med ; 42(4): 357-364, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33022736

RESUMEN

The aims of this study were to investigate the influence of reduced-exertion, high-intensity interval training (REHIT), comparing a novel shortened-sprint protocol (SSREHIT) against a traditional protocol (TREHIT), on perceptual responses and to determine if changes in peak oxygen uptake (V˙O2peak) are attenuated with shorter sprints. Twenty-four healthy men undertook 15 sessions of SSREHIT or TREHIT. V˙O2peak was determined at baseline and after completion of each exercise condition. Affective (pleasure-displeasure) responses and perceived exertion were assessed during exercise to capture peak responses. Enjoyment was recorded 5-min after cessation of exercise. Compared to baseline, V˙O2peak increased in both groups (6% for SSREHIT [d=- 0.36] and 9% for TREHIT [d=- 0.53], p=0.01). Affective responses were more favourable for SSREHIT (p=0.001, d=1.62), but both protocols avoided large negative peaks of displeasure. Peak ratings of perceived exertion were lower for SSREHIT (p=0.001, d=- 1.71), although there were no differences in enjoyment (d=0.25). The results demonstrate both exercise conditions can increase V˙O2peak without overly compromising perceptual responses. Decreased sprint duration might further circumvent negative perceptual responses but might also attenuate physiological adaptations.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad/métodos , Consumo de Oxígeno/fisiología , Placer/fisiología , Adaptación Fisiológica , Afecto/fisiología , Ciclismo/fisiología , Entrenamiento de Intervalos de Alta Intensidad/psicología , Humanos , Masculino , Esfuerzo Físico/fisiología , Factores de Tiempo , Adulto Joven
12.
Synth Biol (Oxf) ; 5(1): ysaa010, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32995552

RESUMEN

Multi-part DNA assembly is the physical starting point for many projects in Synthetic and Molecular Biology. The ability to explore a genetic design space by building extensive libraries of DNA constructs is essential for creating programmed biological systems. With multiple DNA assembly methods and standards adopted in the Synthetic Biology community, automation of the DNA assembly process is now receiving serious attention. Automation will enable larger builds using less researcher time, while increasing the accessible design space. However, these benefits currently incur high costs for both equipment and consumables. Here, we address this limitation by introducing low-cost DNA assembly with BASIC on OpenTrons (DNA-BOT). For this purpose, we developed an open-source software package and demonstrated the performance of DNA-BOT by simultaneously assembling 88 constructs composed of 10 genetic parts, evaluating the promoter, ribosome binding site and gene order design space for a three-gene operon. All 88 constructs were assembled with high accuracy, at a consumables cost of $1.50-$5.50 per construct. This illustrates the efficiency, accuracy and affordability of DNA-BOT, making it accessible for most labs and democratizing automated DNA assembly.

13.
Methods Mol Biol ; 2205: 239-253, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32809203

RESUMEN

Biopart Assembly Standard for Idempotent Cloning (BASIC) is a simple, robust, and highly accurate DNA assembly method, which provides 99% correct assemblies for a typical four-part assembly, enabling high efficiency cloning workflows (Storch et al., ACS Synth Biol, https://doi.org/10.1021/sb500356 , 2015). BASIC employs standardised DNA linkers to combine bioparts, stored in the universal BASIC format. Once a new biopart is formatted into BASIC standard, defined by flanking 18 bp prefix and suffix sequences, it can be placed at any position and in any context within a designed BASIC assembly. This modularity of the BASIC approach is further enhanced by a range of functional linkers, including genetic elements like ribosomal binding sites (RBS) and peptide linkers. The method has a single tier format, whereby any BASIC assembly can create a new composite BASIC part in the same format used for the original parts; it can thus enter a subsequent BASIC assembly without the need for reformatting or changes to the workflow. This unique idempotent cloning mechanism allows for the assembly of constructs in multiple, conceptionally simple hierarchical rounds. Combined with its high accuracy and robustness, this makes BASIC a versatile assembly method for combinatorial and complex assemblies both at bench and biofoundry scale. The single universal storage format of BASIC parts enables compressed universal biopart libraries that promote sharing of parts and reproducible assembly strategies across labs, supporting efforts to improve reproducibility. In comparison with other DNA assembly standards and methods, BASIC offers a simple robust protocol, relies on a single tier format, provides for easy hierarchical assembly, and is highly accurate for up to seven parts per assembly round (Casini et al., Nat Rev Mol Cell Biol. https://doi.org/10.1038/nrm4014 , 2015).


Asunto(s)
Clonación Molecular/métodos , ADN/genética , Ingeniería Genética/métodos , Vectores Genéticos/genética , Reproducibilidad de los Resultados , Proyectos de Investigación , Biología Sintética/métodos
14.
Artículo en Inglés | MEDLINE | ID: mdl-32099663

RESUMEN

BACKGROUND: Physical activity and exercise interventions to improve health frequently bring about intended effects under ideal circumstances but often fail to demonstrate benefits in real-world contexts. The aim of this study was to describe the feasibility of an exercise intervention (reduced-exertion, high-intensity interval training) in non-diabetic hyperglycaemia patients delivered in a National Health Service setting to assess whether it would be appropriate to progress to a future large-scale study. METHODS: The intention was to recruit 40 participants from a single centre (specialist diabesity centre). Patients were eligible to take part if they were diagnostically defined as non-diabetic hyperglycaemic based on a glycated haemoglobin (HbA1c) value of 42-46 mmol mol. Study procedures including recruitment, occurrence of adverse events, intervention acceptability, and intervention adherence were used to assess feasibility. RESULTS: Key criteria for progression to a larger study were not met. The study revealed several issues including patient eligibility, challenges to recruitment, patient consent, and poor clinician engagement. Furthermore, despite the simplicity and convenience of using HbA1c to screen for diabetes risk, the process of accurately screening and case finding eligible patients was problematic. The small sample recruited for this trial (n = 6) also limits the interpretation of data, thus it is not possible to estimate the variability of intended outcomes to use in a formal sample size calculation for a full-scale trial. Some aspects of the intervention worked well. The acceptability of the exercise intervention and outcome measures met progression criteria thresholds and adherence was very high, with 97% of exercise sessions completed for participants that finished the study. CONCLUSIONS: Given the issues, the trial is not feasible in its current form. Yet, this preparatory stage of trial design pre-empted problems with the intervention that could be changed to optimise the design and conduct of future studies. Solutions to the issues identified in this study revolve around using a dedicated local recruiter with a strong relationship among the healthcare team and patients, using participant incentives to take part, and allowing for a longer recruitment period. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04011397. Registered 07 July 2019-retrospectively registered.

15.
Res Q Exerc Sport ; 91(4): 692-704, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32023187

RESUMEN

Purpose: The purpose of the study is to investigate biomechanical and physiological responses to soccer-specific exercise incorporating an extra-time period (ET) and assess the test-retest reliability of these responses. Methods: Twelve soccer players performed 120 min of soccer-specific exercise. Tri-axial (PLTotal) and uni-axial PlayerLoad™ in the vertical (PLV), anterior-posterior (PLA-P), and medial-lateral (PLM-L) planes were monitored using a portable accelerometer. Likewise, respiratory exchange ratio (RER) was recorded throughout exercise. At the end of each 15-min period, players provided differential ratings of perceived exertion for legs (RPE-L), breathlessness (RPE-B) and overall (RPE-O), and capillary samples were taken to measure blood lactate (BLa) concentrations. The soccer-specific exercise was completed twice within 7 days to assess reliability. Results: A main effect for time was identified for PLTotal (p = 0.045), PLV (p = 0.002), PLA-P (p = 0.011), RER (p = 0.001), RPE-L (p = 0.001), RPE-O (p = 0.003), and CMJ (p = 0.020). A significant increase in PLTotal (234 ± 34 au) and decrease in RER (0.87 ± 0.03) was evident during 105-120 versus 0-15 min (215 ± 25 au; p = 0.002 and 0.92 ± 0.02; p = 0.001). Coefficients of variations were <10% and Pearson's correlation coefficient demonstrated moderate-to-very strong (0.33-0.99) reliability for all PL variables, RPE-B, BLa, and RER. Conclusions: These results suggest that mechanical efficiency is compromised and an increased rate of lipolysis is observed as a function of exercise duration, particularly during ET. These data have implications for practitioners interested in fatigue-induced changes during ET.


Asunto(s)
Resistencia Física/fisiología , Fútbol/fisiología , Fenómenos Biomecánicos , Humanos , Ácido Láctico/sangre , Pierna/fisiología , Lipólisis , Fatiga Muscular/fisiología , Percepción/fisiología , Esfuerzo Físico/fisiología , Intercambio Gaseoso Pulmonar , Factores de Tiempo
16.
J Sports Sci ; 38(2): 121-129, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31661663

RESUMEN

A common barrier to exercise is "lack of time". Accordingly, interest in low-volume, high-intensity training has grown exponentially since this activity is considered time-efficient. However, the high-intensity nature of this exercise may frequently result in feelings of displeasure creating another barrier for many people. The purpose of this study was to compare affective (pleasure-displeasure) responses to three low-volume, high-intensity exercise conditions, including a novel shortened-sprint protocol. Using a within-subjects, randomised crossover experiment, healthy participants (N = 36) undertook a single bout of: 1) traditional reduced-exertion, high-intensity interval training (TREHIT), 2) a novel, shortened-sprint REHIT (SSREHIT) protocol, and 3) sprint continuous training (SCT). Affect and perceived efforts were recorded throughout exercise using the Feeling Scale (FS) and the 15-point Borg Rating of Perceived Exertion (RPE) scale, respectively. Enjoyment was recorded 5 min post-exercise using the Exercise Enjoyment Scale (EES). Differences were found for FS (condition by time interaction: P = 0.01GG, η2 = 0.26), RPE (P = 0.01GG, η2 = 0.23), and enjoyment (P < 0.01) with all outcomes favouring SSREHIT. Shortened-sprint protocols may diminish feelings of displeasure and might be a time-efficient yet tolerable exercise choice to help motivate some people to increase their physical activity and fitness.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad/métodos , Entrenamiento de Intervalos de Alta Intensidad/psicología , Placer , Adulto , Estudios Cruzados , Femenino , Humanos , Masculino , Motivación , Percepción/fisiología , Esfuerzo Físico/fisiología , Adulto Joven
17.
Phys Ther Sport ; 39: 32-37, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31229679

RESUMEN

OBJECTIVE: To assess glenohumeral joint (GHJ) rotation strength across a rugby league season, since strength of rotator cuff musculature may protect against contact injuries to the shoulder. DESIGN: A prospective cohort study was used to compare GHJ rotation pre-, in-, and post-season. SETTING: Laboratory. PARTICIPANTS: Twenty-nine players from a professional European Super League club. MAIN OUTCOME MEASURES: Isokinetic dynamometry for concentric and eccentric muscle actions for shoulder internal and external rotation at 240°/s. Peak torque, traditional strength ratios, and dynamic control ratios were compared. RESULTS: There were no significant differences between peak torque strength parameters at any time point. Similarly, differences in strength ratios failed to reach statistical significance across the season. Ipsilateral strength ratios were indicative of selective strengthening of internal rotators for concentric and eccentric muscle actions. CONCLUSIONS: The findings suggest that rugby league players are no more likely to sustain a shoulder injury in the latter stages of the season as a result of decreased GHJ rotation strength. Players were able to maintain strength across the season which is valuable to practitioners developing conditioning programmes to optimise performance and minimise the risk of injury. This may afford protection, particularly during forced external rotation following physical contact.


Asunto(s)
Fuerza Muscular/fisiología , Estaciones del Año , Articulación del Hombro/fisiología , Adolescente , Adulto , Estudios de Cohortes , Fútbol Americano/fisiología , Humanos , Masculino , Dinamómetro de Fuerza Muscular , Rotación , Adulto Joven
18.
Synth Biol (Oxf) ; 4(1): ysz019, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32995542

RESUMEN

In vitro selection of ligand-responsive ribozymes can identify rare, functional sequences from large libraries. While powerful, key caveats of this approach include lengthy and demanding experimental workflows; unpredictable experimental outcomes and unknown functionality of enriched sequences in vivo. To address the first of these limitations, we developed Ligase-Assisted Selection for the Enrichment of Responsive Ribozymes (LigASERR). LigASERR is scalable, amenable to automation and requires less time to implement compared to alternative methods. To improve the predictability of experiments, we modeled the underlying selection process, predicting experimental outcomes based on sequence and population parameters. We applied this new methodology and model to the enrichment of a known, in vitro-selected sequence from a bespoke library. Prior to implementing selection, conditions were optimized and target sequence dynamics accurately predicted for the majority of the experiment. In addition to enriching the target sequence, we identified two new, theophylline-activated ribozymes. Notably, all three sequences yielded riboswitches functional in Escherichia coli, suggesting LigASERR and similar in vitro selection methods can be utilized for generating functional riboswitches in this organism.

19.
J Strength Cond Res ; 32(6): 1685-1691, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29786625

RESUMEN

Haines, MR. Differences in glenohumeral joint rotation and peak power output between Super League and Championship Rugby League players. J Strength Cond Res 32(6): 1685-1691, 2018-Rugby league is a high-intensity sport with large impact forces sustained during play, resulting in high prevalence of shoulder injury. Consequently, shoulder strength and player power are important considerations for injury prevention and performance. Additionally, professional teams regularly compete against semiprofessional teams, where differences in physical conditioning could be marked. The aim of this study was to test for differences in glenohumeral joint rotation and peak power between a professional Super League (SL) and semiprofessional Rugby League Championship (RLC) teams. A cross-sectional analysis was used to test 25 SL and 24 RLC players during preseason training. Isokinetic dynamometry, at 240°·s for concentric and eccentric actions was used to assess glenohumeral rotation. Peak power was determined using a maximal 30-second cycle ergometer test. Selective muscular development of the internal rotators without concomitant external rotator strength was evident in the SL team but not the RLC team. Internal rotation peak torque was higher for the SL club for concentric (∼24%) and eccentric (∼16%) muscle actions (p ≤ 0.05), and this contributed to a lower ipsilateral reciprocal muscle group ratio (external to internal concentric) for the SL team compared with the RLC team (∼47% and ∼60% respectively; p ≤ 0.05). Peak power output was also higher for the SL team (1,409 ± 153 vs. 1,273 ± 159 W; p ≤ 0.05). The results highlight a mismatch in the physical conditioning of SL and RLC players with implications for practitioners to design strength and conditioning programs that minimize the risk of injury while optimizing performance.


Asunto(s)
Fútbol Americano/fisiología , Fuerza Muscular/fisiología , Articulación del Hombro/fisiología , Adulto , Estudios Transversales , Humanos , Masculino , Rango del Movimiento Articular , Torque , Adulto Joven
20.
Nucleic Acids Res ; 45(8): 4984-4993, 2017 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-28369627

RESUMEN

The ability to program cellular behaviour is a major goal of synthetic biology, with applications in health, agriculture and chemicals production. Despite efforts to build 'orthogonal' systems, interactions between engineered genetic circuits and the endogenous regulatory network of a host cell can have a significant impact on desired functionality. We have developed a strategy to rewire the endogenous cellular regulatory network of yeast to enhance compatibility with synthetic protein and metabolite production. We found that introducing novel connections in the cellular regulatory network enabled us to increase the production of heterologous proteins and metabolites. This strategy is demonstrated in yeast strains that show significantly enhanced heterologous protein expression and higher titers of terpenoid production. Specifically, we found that the addition of transcriptional regulation between free radical induced signalling and nitrogen regulation provided robust improvement of protein production. Assessment of rewired networks revealed the importance of key topological features such as high betweenness centrality. The generation of rewired transcriptional networks, selection for specific phenotypes, and analysis of resulting library members is a powerful tool for engineering cellular behavior and may enable improved integration of heterologous protein and metabolite pathways.


Asunto(s)
Redes Reguladoras de Genes/genética , Ingeniería Genética , Biología Sintética , Terpenos/química , Regulación de la Expresión Génica , Humanos , Ingeniería Metabólica , Nitrógeno/química , Nitrógeno/metabolismo , Fenotipo , Saccharomyces cerevisiae/genética , Terpenos/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...