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1.
Phys Rev Lett ; 132(25): 251904, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38996272

RESUMEN

The gravitational form factors (GFFs) of a hadron encode fundamental aspects of its structure, including its shape and size as defined from, e.g., its energy density. This Letter presents a determination of the flavor decomposition of the GFFs of the proton from lattice QCD, in the kinematic region 0≤-t≤2 GeV^{2}. The decomposition into up-, down-, strange-quark, and gluon contributions provides first-principles constraints on the role of each constituent in generating key proton structure observables, such as its mechanical radius, mass radius, and D term.

2.
J Strength Cond Res ; 38(2): 394-404, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38090981

RESUMEN

ABSTRACT: Hackett, DA, Li, J, Wang, B, Way, KL, Cross, T, and Tran, DL. Acute effects of resistance exercise on intraocular pressure in healthy adults: A systematic review. J Strength Cond Res 38(2): 394-404, 2024-Intraocular pressure (IOP) tends to fluctuate during a resistance exercise (RE). This systematic review examines the acute effects of RE on IOP in healthy adults and factors that influence changes in IOP. Five electronic databases were searched using terms related to RE and IOP. A strict inclusion criterion was applied, which included being 55 years or younger with no medical conditions and RE intensity needing to be quantifiable (e.g., based on a maximal effort). Thirty-four studies met the inclusion criteria for this review. Isometric and isotonic contractions produced similar changes in IOP during RE up to 28.7 mm Hg. Exercises that involved larger muscle mass, such as squats and leg press, were found to produce changes in IOP during exercise ranging from 3.1 to 28.7 mm Hg. Smaller changes in IOP during RE were found for exercises engaging less muscle mass (e.g., handgrip and bicep curls). Intraocular pressure was found to increase during RE when lifting heavier loads and with longer exercise durations (e.g., greater repetitions). The Valsalva maneuver (VM) and breath-hold during RE accentuated the change in IOP, with more extreme changes observed with the VM. However, most studies showed that postexercise IOP returned to baseline after approximately 1 minute of recovery. An acute increase in IOP is observed during RE in healthy adults with fluctuations of varying magnitude. Factors that independently increase IOP during RE include exercises involving larger muscle mass, heavy loads, greater set duration, and when the VM or breath-hold is performed.


Asunto(s)
Presión Intraocular , Entrenamiento de Fuerza , Adulto , Humanos , Fuerza de la Mano , Tonometría Ocular , Ejercicio Físico/fisiología
3.
Arch Phys Med Rehabil ; 104(11): 1928-1940, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37098358

RESUMEN

OBJECTIVE: To examine the evidence regarding the potential of hybrid functional electrical stimulation (FES) cycling for improving cardiorespiratory fitness for people with a mobility disability related to a central nervous system (CNS) disorder. DATA SOURCES: Nine electronic databases: MEDLINE, EMBASE, Web of Science, CINAHL, PsycInfo, SPORTDiscus, Pedro, Cochrane, and Scopus, were searched from inception until October 2022. STUDY SELECTION: Search terms included multiple sclerosis, spinal cord injury (SCI), stroke, Parkinson's disease, cerebral palsy, synonyms of FES cycling, arm crank ergometry (ACE) or hybrid exercise, and V̇o2. All experimental studies, including randomized controlled trials that included an outcome measure related to peak or sub-maximal V̇o2 were eligible. DATA EXTRACTION: From a total of 280 articles, 13 were studies included. The Downs and Black Checklist was used to assess study quality. Random effects (Hedges' g) meta-analyses were undertaken to determine whether there were differences in V̇o2peak during acute bouts of hybrid FES cycling vs other modes of exercise and changes resulting from longitudinal training. DATA SYNTHESIS: During acute bouts of exercise, hybrid FES cycling was moderately more effective than ACE (effect size [ES] of 0.59 (95% CI 0.15-1.02, P=.008) in increasing V̇o2peak from rest. There was a large effect on the increase of V̇o2peak from rest for hybrid FES cycling compared with FES cycling (ES of 2.36 [95% CI 0.83-3.40, P=.003]). Longitudinal training with hybrid FES cycling showed a significant improvement in V̇o2peak from pre to post intervention with a large, pooled ES of 0.83 (95% CI 0.24-1.41, P=.006). CONCLUSIONS: Hybrid FES cycling produced higher V̇o2peak compared with ACE or FES cycling during acute bouts of exercise. Hybrid FES cycling can improve cardiorespiratory fitness in people with SCI. Additionally, there is emerging evidence that hybrid FES cycling might increase aerobic fitness in people with mobility disability related to CNS disorders.


Asunto(s)
Capacidad Cardiovascular , Terapia por Estimulación Eléctrica , Traumatismos de la Médula Espinal , Humanos , Brazo , Terapia por Estimulación Eléctrica/métodos , Terapia por Ejercicio/métodos , Estimulación Eléctrica
4.
Eur Arch Otorhinolaryngol ; 280(8): 3515-3528, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37093291

RESUMEN

INTRODUCTION: COVID-19 can result in an extensive range of extrapulmonary, and neurological signs and symptoms such as olfactory and/or taste dysfunction, and otologic symptoms. The aim of this study was to investigate the hearing loss manifestation from COVID-19. METHODS: The goal of this umbrella review was to examine hearing loss associated with COVID-19 disease. English literature published until October 15, 2022 in online databases including PubMed, Scopus, Web of Science, and Embase was considered for this purpose. Eligibility of the articles for subsequent data extraction was evaluated in a two-step selection process with consideration to an inclusion/exclusion criterion. This review followed the PRISMA protocol and the Amstar-2 checklist for quality assessment. RESULTS: A total of four treatment strategies were used by different studies which included oral corticosteroids, intratympanic corticosteroids, combined oral and intratympanic corticosteroids, and hyperbaric oxygen therapy. Five studies investigated corticosteroid use in the forms of oral or intratympanic injection; four studies reported (complete or partial) hearing improvements after steroid treatment, while one study stated no significant improvement in hearing function. One study reported that oral corticosteroid monotherapy alone was not effective, while vestibular symptoms were ameliorated by a combination of oral prednisone, intratympanic dexamethasone injection, and hydroxychloroquine. CONCLUSION: The findings suggest that despite being one of the rare complications of COVID-19, hearing loss can impact a patient's quality of life. The most common type reported was sensorineural hearing loss, which can be diagnosed with variable techniques.


Asunto(s)
COVID-19 , Sordera , Pérdida Auditiva Sensorineural , Pérdida Auditiva Súbita , Humanos , Pérdida Auditiva Súbita/diagnóstico , Calidad de Vida , COVID-19/complicaciones , Pérdida Auditiva Sensorineural/diagnóstico , Corticoesteroides/uso terapéutico , Inyección Intratimpánica , Resultado del Tratamiento , Dexametasona/uso terapéutico , Glucocorticoides/uso terapéutico
5.
BMC Med Educ ; 23(1): 435, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37312134

RESUMEN

BACKGROUND: Workplace violence continues among medical students in training. This study aimed to determine the reactions and perspectives of medical students against workplace violence during clinical training in Ardabil University of Medical Sciences in Iran, 2020. MATERIALS: This descriptive cross-sectional study was conducted on 300 medical students from April to March 2020, in the Ardabil university hospitals. Students with at least one year training in the university hospitals were eligible to participate. Data was collected via questionnaires administered in the health ward. Data was analyzed through SPSS 23 software. RESULTS: Most respondents had experienced workplace violence in the form of verbal (63%), physical (25.7%), racial (23%) and sexual (3%) violence during clinical training. Men were the aggressors during violence of a physical (80.5%), verbal (69.8%), racial (76.8%) and sexual (100%) nature (p < 0.001). When encountered with violence, 36% of the respondents did not take any action and 82.7% of respondents failed to report the incident. For 67.8% of respondents that did not report of violence incident, this procedure was deemed pointless, while 27% of respondents considered the violent incident insignificant. The main reason for workplace violence was perceived to be a lack of awareness of people about staff duties (67.3% of respondents). According to 92.7% of respondents personnel training was the most important factor in preventing workplace violence. CONCLUSIONS: The findings suggest that the majority of medical students during clinical training in Ardabil Iran (2020) have been exposed to workplace violence. However, most students did not take any action or report the incident. Targeted personnel training, increase awareness of workplace violence, and encouragement of reporting these incidents should be promoted to reduce violence to medical students.


Asunto(s)
Estudiantes de Medicina , Violencia Laboral , Masculino , Humanos , Violencia Laboral/prevención & control , Estudios Transversales , Irán , Hospitales Universitarios
6.
J Strength Cond Res ; 37(6): 1191-1198, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36730216

RESUMEN

ABSTRACT: Davies, TB, Li, J, and Hackett, DA. Effect of high-volume cluster sets vs. lower-volume traditional sets on accuracy of estimated repetitions to failure. J Strength Cond Res 37(6): 1191-1198, 2023-This study investigated the effects of resistance training using cluster (CLUS) vs. traditional (TRAD) set structures on the accuracy of estimated repetitions to failure (ERF). Nineteen healthy male resistance trainers (age 21.0 ± 4.4 years) were randomized into 1 of the 2 bench press training routines performed for 6 weeks. Cluster ( n = 10) performed 6 sets of 5 repetitions at 85% of 1 repetition maximum (1RM) with 30-second interrepetition rest and 3 minutes of interset rest. Traditional ( n = 9) performed 3 sets of 5 repetitions at 85% 1RM with 5 minutes of interset rest. Maximum repetitions at 85% 1RM was performed before and after intervention to assess error in ERF and mean concentric velocity (MCV). The ERF, rating of perceived exertion, and maintenance of MCV were assessed throughout the intervention. Rating of perceived exertion was lower for sets 1-3 in CLUS compared with TRAD from weeks 1 to 4 (effect size [ES] = 0.8-2.4, p ≤ 0.04). The ERF was greater for sets 1-3 in CLUS than in TRAD during all intervention weeks (ES = 1.0-5.1, p ≤ 0.04). Maintenance of MCV was greater in CLUS compared with TRAD for all sets at week 1 (ES = 0.76, p = 0.002) and sets 4-6 at week 6 (ES = 0.77, p = 0.006). After the intervention, error in ERF did not change, and no differences were found between the groups. Findings indicate that accuracy of ERF does not improve after resistance training using set structures that induce different transient fatigue-related effects when using high loads in experienced resistance trainers.


Asunto(s)
Músculo Esquelético , Entrenamiento de Fuerza , Adolescente , Adulto , Humanos , Masculino , Adulto Joven , Etnicidad , Fuerza Muscular , Descanso , Levantamiento de Peso
7.
J Strength Cond Res ; 37(5): 1079-1088, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36165879

RESUMEN

ABSTRACT: Li, J, Davies, TB, and Hackett, DA. Self-reported training and supplementation practices between performance-enhancing drug-user bodybuilders compared with natural bodybuilders. J Strength Cond Res 37(5): 1079-1088, 2023-This study aimed to examine whether the training and supplementation practices differ between performance-enhancing drug (PED)-using bodybuilders (BB) and natural BB. One hundred eighty-seven competitive male bodybuilders with a median age of 27.0 years completed an online survey. Of this sample, 40 respondents reported using PED (PED-user) and 147 respondents reported to be natural. Compared with natural BB, PED-user BB reported greater off-season body weight ( p < 0.001) and weight loss before a competition ( p < 0.001). In the off-season, PED-user BB performed a greater number of exercises per muscle group ( p < 0.001), number of repetition maximum (RM) per set ( p < 0.01), and less recovery between the sets ( p < 0.01). During the precompetition phase, the natural BB increased their number of RM; however, the PED-user BB still reported using a greater number of RM per set ( p = 0.02), exercises per muscle group ( p < 0.001), and less recovery time between the sets ( p < 0.01). Both the PED-user BB and natural BB reported greater aerobic exercise frequency ( p < 0.001) and session duration ( p < 0.001), although PED-user BB performed a greater number of aerobic exercise sessions ( p = 0.04) and at a higher intensity ( p < 0.01). Advanced training techniques, including negatives, partial repetitions, preexhaustion sets, and timed repetitions, were more popular among PED-user BB ( p < 0.05). Creatine monohydrate usage was more popular among natural BB ( p < 0.001), whereas branched-chain and essential amino acids were more popular among PED-user BB ( p ≤ 0.001). Findings suggest that PED-user BB perform more metabolically demanding resistance training sessions, more strenuous aerobic training during the precompetition phase, and may have different supplementation preferences compared with natural BB.


Asunto(s)
Sustancias para Mejorar el Rendimiento , Entrenamiento de Fuerza , Humanos , Masculino , Adulto , Autoinforme , Levantamiento de Peso/fisiología , Ejercicio Físico , Entrenamiento de Fuerza/métodos , Suplementos Dietéticos , Músculo Esquelético/fisiología , Fuerza Muscular/fisiología
8.
J Strength Cond Res ; 37(5): e325-e331, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36227221

RESUMEN

ABSTRACT: Hackett, DA, He, W, Fleeton, JRM, Orr, R, and Sanders, RH. Effects of age and sex on aerobic fitness, sprint performance, and change of direction speed in high school athletes. J Strength Cond Res 37(5): 325-331, 2023-The purpose of this study was to examine the effects of sex and age on aerobic fitness, sprinting performance, and change of direction speed (CODS) in high school athletes, with consideration for maturity. This cross-sectional study involved 2,132 adolescents (1,415 male and 717 female athletes) aged 12.0-15.9 years. Assessment of aerobic fitness using the 20-m multistage fitness test (20MSFT) and 20-m sprint and CODS using the 505 test was performed. For the analysis of data, subjects were separated into 4 age groups: U/13 years, U/14 years, U/15 years, and U/16 years. Estimated age at peak height velocity was a covariate in the data analysis to control for maturity status. Compared with female athletes, male athletes had superior performances at all age groups in 10-m sprint ( p < 0.001, effect size [ES] = >-0.44), 20-m sprint ( p < 0.001, ES = >-0.55), and 505 test ( p < 0.001, ES = >-0.41). Female athletes performed better than male athletes in 20MSFT at U/13 ( p < 0.01, ES = -0.22); however, male athletes had better performances at U/15 ( p < 0.01, ES = 0.27) and U/16 ( p < 0.001, ES = 0.67). At each consecutive age group, male athletes improve their performances in 20MSFT and sprints and at U/14 and U/16 in the 505 test ( p < 0.001, ES > -0.37). Female athletes showed no improvement in the 20MSFT and 505 test between U/13-U/16 but showed improved sprint performance at U/15 compared with U/13 and at U/16 compared with U/14 ( p < 0.05). This study shows that adolescent male athletes perform consistently better than female athletes in running-related field-based tests and display continuous improvements across age groups.


Asunto(s)
Rendimiento Atlético , Carrera , Adolescente , Humanos , Masculino , Femenino , Lactante , Estudios Transversales , Ejercicio Físico , Atletas
9.
Transp Res Rec ; 2677(2): 50-61, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37038442

RESUMEN

U.S. container ports have experienced unpresented congestion since mid-2020. The congestion is generally attributed to import surges triggered by heavy spending on consumer goods during the COVID-19 pandemic. Port congestion has been compounded by the inability of importers to retrieve, receive, and process all the inbound goods they have ordered, resulting in supply chain shortfalls and economic disruption. How can the shipping industry and government organizations predict the end of the current surge and anticipate future surges? Expected seasonal variations in import volume are associated with peak holiday shopping periods; nonseasonal import surges are signaled by other factors. The research goes beyond transportation data sources to examine broader connections between import volume and indicators of economic and retail industry conditions. The strongest and most useful relationship appears to be between retail inventory indicators and containerized import growth. From January 2018 through July 2021, there was a relatively strong negative correlation between retail inventory- and import TEU indices with a 4-month lag (corresponding roughly to the time between import orders and -arrival). In the 2020 to 2021 pandemic period the negative correlation was stronger, again with a 4-month lag. These findings suggest that observers might anticipate import surges after marked, nonseasonal drops in retail inventories, and that import surges are likely to last until target inventory levels are restored. In a broader sense, an awareness of the linkages between consumer demand, retail chain responses, and containerized import volumes could better inform port, freight transportation, and government planning and policy choices.

10.
J Strength Cond Res ; 36(4): 963-970, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33651737

RESUMEN

ABSTRACT: Hackett, DA. Training, supplementation, and pharmacological practices of competitive male bodybuilders across training phases. J Strength Cond Res 36(4): 963-970, 2022-Bodybuilding involves the pursuit of muscularity and leanness primarily through the use of progressive resistance training in combination with other practices such as manipulation of diet and use of ergogenic aids. This study aimed to compare the training practices and ergogenic aids used by competitive male bodybuilders across training phases. An online survey was completed by 235 competitive male bodybuilders with a median age of 26.0 (interquartile range 23.0-31.3) years. Results showed that most respondents performed split-routines (85.5%), 4-7 sessions per week (95.7%), trained major muscle groups twice a week (>50%), and session duration being 60-90 minutes (55.7%). Off-season resistance training sessions mostly comprised of targeting 2-3 muscle groups (56%), 2-3 exercises per muscle group (60.4%), 3-4 sets per exercise (73.2%), 7-12 repetition maximum (RM) per set (71.6%), and 61-180 seconds recovery between sets and exercises (80.5%). At the precompetition phase (6 weeks before competition), there was a decrease in the number of muscle groups trained per session (p = 0.027) and a greater number of repetitions performed per set (p < 0.001). A significant increase in the reported aerobic exercise volume was found during precompetition (<0.001). Performance enhancing drugs were used by 53.6% of respondents who did not compete in natural bodybuilding competitions. Dietary supplements were used by 95.7% of respondents with the most common being creatine monohydrate (80.4%) and whey protein (65.8%). Findings suggest that competitive bodybuilders follow resistance training practices consistent with the broad muscular hypertrophy recommendations but a notable shift in practices occur in the weeks before competition.


Asunto(s)
Sustancias para Mejorar el Rendimiento , Entrenamiento de Fuerza , Adulto , Creatina , Dieta , Suplementos Dietéticos , Humanos , Masculino , Músculo Esquelético , Entrenamiento de Fuerza/métodos , Adulto Joven
11.
J Strength Cond Res ; 36(10): 2701-2708, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33938720

RESUMEN

ABSTRACT: Hackett, DA. Influence of movement velocity on accuracy of estimated repetitions to failure in resistance-trained men. J Strength Cond Res 36(10): 2701-2708, 2022-This study explored the accuracy in estimated repetitions to failure (ERF) and changes in mean concentric velocity (MCV) during resistance exercise. Twenty male resistance trainers (age, 26.3 ± 6.9 years; body mass, 82.0 ± 6.0 kg; stature, 178.0 ± 5.5 cm) completed 5 sets of 10 repetitions for the bench press and squat at 70% one-repetition maximum. Subjects' reported their rating of perceived exertion (RPE) and ERF after the 10th repetition of each set and then continued repetitions to momentary muscle failure (5-minute recovery between sets). Barbell velocity was assessed using a linear position transducer. For the bench press, MCV at repetitions 9-10 decreased as sets progressed ( p ≤ 0.005) with a greater loss of MCV for sets 3-5 vs. set 1 ( p ≤ 0.005). No significant changes in MCV variables were found across sets for the squat. Error in ERF was greater in set 1 for the bench press ( p ≤ 0.005) with no differences for the remaining sets. There were no differences between sets for error in ERF for the squat. Moderate to strong relationships were found between most MCV variables and RPE and ERF, for the bench press ( rs = -049 to 0.73; p ≤ 0.005). For the squat only, MCV at repetitions 9-10 was moderately related with RPE ( rs = -0.33; p ≤ 0.003) and actual repetitions to failure ( rs = 0.31; p ≤ 0.003). No significant relationships were found for error in ERF for either the bench press or squat. Changes in MCV across sets may influence perception of effort and performance for the bench press; however, it does not influence the accuracy in ERF for either exercise.


Asunto(s)
Entrenamiento de Fuerza , Levantamiento de Peso , Adulto , Ejercicio Físico , Terapia por Ejercicio , Humanos , Masculino , Fuerza Muscular , Músculo Esquelético/fisiología , Postura , Levantamiento de Peso/fisiología , Adulto Joven
12.
J Strength Cond Res ; 36(8): 2176-2185, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35916746

RESUMEN

ABSTRACT: Davies, TB, Halaki, M, Orr, R, Mitchell, L, Helms, ER, Clarke, J, and Hackett, DA. Effect of set structure on upper-body muscular hypertrophy and performance in recreationally trained men and women. J Strength Cond Res 36(8): 2176-2185, 2022-This study explored the effect of volume-equated traditional-set and cluster-set structures on muscular hypertrophy and performance after high-load resistance training manipulating the bench press exercise. Twenty-one recreationally trained subjects (12 men and 9 women) performed a 3-week familiarization phase and were then randomized into one of two 8-week upper-body and lower-body split programs occurring over 3 and then progressing to 4 sessions per week. Subjects performed 4 sets of 5 repetitions at 85% one repetition maximum (1RM) using a traditional-set structure (TRAD, n = 10), which involved 5 minutes of interset rest only, or a cluster-set structure, which included 30-second inter-repetition rest and 3 minutes of interset rest (CLUS, n = 11). A 1RM bench press, repetitions to failure at 70% 1RM, regional muscle thickness, and dual-energy x-ray absorptiometry were used to estimate changes in muscular strength, local muscular endurance, regional muscular hypertrophy, and body composition, respectively. Velocity loss was assessed using a linear position transducer at the intervention midpoint. TRAD demonstrated a significantly greater velocity loss magnitude (g = 1.50) and muscle thickness of the proximal pectoralis major (g = -0.34) compared with CLUS. There were no significant differences between groups for the remaining outcomes, although a small effect size favoring TRAD was observed for the middle region of the pectoralis major (g = -0.25). It seems that the greater velocity losses during sets observed in traditional-set compared with cluster-set structures may promote superior muscular hypertrophy within specific regions of the pectoralis major in recreationally trained subjects.


Asunto(s)
Músculo Esquelético , Entrenamiento de Fuerza , Composición Corporal , Femenino , Humanos , Hipertrofia , Masculino , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología
13.
Arch Phys Med Rehabil ; 102(12): 2385-2392, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34283994

RESUMEN

OBJECTIVE: To investigate through a pilot study the acute cardiorespiratory responses during functional electrical stimulation (FES) cycling, arm crank ergometry (ACE), and a combination of ACE and FES cycling (hybrid FES cycling) in people with advanced multiple sclerosis (MS) to provide preliminary guidance for effective aerobic exercise prescription. DESIGN: Acute repeated measures. SETTING: Laboratory setting. PARTICIPANTS: Inclusion criteria was a diagnosis of MS, with Expanded Disability Status Scale (EDSS) 6.0-8.5. Included were 9 participants (N=9; 7 female, age 54.7±8.8y, EDSS 7.2±0.7). INTERVENTIONS: Participants were assessed on 3 different exercise modalities (FES cycling, ACE, hybrid FES cycling) at 40%, 60%, 80%, and 100% of mode-specific peak workload. MAIN OUTCOME MEASURES: Oxygen consumption and heart rate were measured at each workload. RESULTS: Hybrid FES cycling evoked a significantly higher oxygen consumption relative to body weight (V̇o2relative) (mL/kg/min) and heart rate (beats per minute [BPM]) at most workloads compared with ACE or FES cycling. At the 100% workload, heart rate for hybrid FES cycling was 125 BPM (range, 113-148 BPM) and was significantly higher than ACE at 99 BPM (range, 95-119 BPM) (P=.008) and FES cycling at 94 BPM (range, 79-100 BPM) (P=.008). Similarly, at the 100% workload, V̇o2relative for hybrid FES cycling was 11.8 mL/kg/min (range, 7.6-17.6 mL/kg/min) and was significantly higher than ACE at 8.9 mL/kg/min (range, 5.3-12.5 mL/kg/min) (P=.012) and FES cycling at 6.8 mL/kg/min (range, 4.1-9.2 mL/kg/min) (P=.012). CONCLUSIONS: This pilot study showed that hybrid FES cycling can elicit a greater cardiorespiratory response than ACE or FES cycling in people with advanced MS. Thus, hybrid FES cycling might provide a potent enough stimulus to induce clinically relevant changes in cardiorespiratory fitness. Training studies are warranted to document the magnitude and sustainability of aerobic capacity adaptations to hybrid FES cycling and associated health outcomes in advanced MS.


Asunto(s)
Capacidad Cardiovascular/fisiología , Terapia por Estimulación Eléctrica/métodos , Terapia por Ejercicio/métodos , Esclerosis Múltiple/terapia , Consumo de Oxígeno/fisiología , Adulto , Anciano , Ciclismo , Terapia Combinada , Ergometría , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto
14.
Scand J Med Sci Sports ; 31(3): 720-732, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33185897

RESUMEN

To evaluate the effect of combined resistance and aerobic training (RT+AT) on regional bone mineral density (BMD) and physical performance in people living with HIV (PLWH). Forty PLWH (20 men and 20 women) were randomized into RT+AT group (n = 20; age = 38.3 ± 4.9) or non-exercise control group (n = 20; age = 37.9 ± 5.1). The RT+AT group was required to perform a nonlinear periodized resistance training program targeting large muscle groups followed by 20 min aerobic exercise at 65-80% of maximal heart rate. Participants in RT+AT performed three supervised sessions per week for 6-months, whereas participants in the control group were instructed to continue with their current lifestyle habits. The primary outcome was bone mineral density (lumbar spine (L2-L4), femoral neck, and distal 1/3 radius). Secondary outcomes included physical function, anthropometry, inflammatory markers, and growth factors. The RT+AT group demonstrated a significant increase in BMD at follow-up for the Lumbar spine (L2-L4), femoral neck, and 1/3 radius (all, P < .05), and There were no gender differences in the training response between men and women for any of the BMD regions. Similar findings were also observed for lean body mass, IGF1and Adiponectin (P < .001). We observed a decrease in percent body fat, fat mass, IL-6, TNF-α, and myostatin in the RT+AT group (P < .001). Finally, there was a significant increase in handgrip strength and gait speed for both women and men in the RT+AT group (P < .001). A combination of resistance and aerobic training appears to be a feasible and effective means for counteracting bone loss and improving various inflammatory markers, physical function, and growth hormones in PLWH.


Asunto(s)
Densidad Ósea/fisiología , Infecciones por VIH/fisiopatología , Acondicionamiento Físico Humano/métodos , Entrenamiento de Fuerza , Adiponectina/sangre , Adulto , Biomarcadores/sangre , Índice de Masa Corporal , Femenino , Fibronectinas/sangre , Fuerza de la Mano , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , Miostatina/sangre , Rendimiento Físico Funcional , Método Simple Ciego , Factor de Necrosis Tumoral alfa/sangre , Velocidad al Caminar
15.
J Sports Sci ; 39(9): 955-960, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33242289

RESUMEN

Field-based tests including the medicine ball chest throw (MBCT) and vertical jump are used to assess muscle performance. To date no study has compared performances of these field-based tests in adolescents across a range of ages. The aim of this study was to examine the effects of age and sex on MBCT and countermovement jump (CMJ) performance in adolescents.This cross-sectional study involved 2192 adolescents (1477 males and 715 females) aged between 12 and 17 years. Trials of the MBCT and CMJ were performed with CMJ peak power estimated. Males had significantly greater MBCT distance, CMJ height and CMJ peak power at each consecutive age group separated by 1 year (p < 0.001). Females generally showed significantly greater performances across a larger age range of at least 2 years for MBCT (p ≤ 0.004) and CMJ peak power (p ≤ 0.018). Males had greater performances than females for MBCT distance, CMJ height, and CMJ peak power from 13 years and above (p < 0.001). Sex differences widened with increasing age for all tests from ~5-8% at 12 years progressing to 24-29% at 16-17 years. This study shows the effects of age and sex is similar for both the MBCT and CMJ tests in adolescents.


Asunto(s)
Factores de Edad , Rendimiento Atlético/fisiología , Fuerza Muscular/fisiología , Factores Sexuales , Adolescente , Niño , Femenino , Humanos , Masculino , Movimiento/fisiología , Nueva Gales del Sur
16.
J Strength Cond Res ; 2021 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-33927112

RESUMEN

ABSTRACT: Davies, TB, Halaki, M, Orr, R, Mitchell, L, Helms, ER, Clarke, J, and Hackett, DA. Effect of set structure on upper-body muscular hypertrophy and performance in recreationally trained men and women. J Strength Cond Res XX(X): 000-000, 2021-This study explored the effect of volume-equated traditional-set and cluster-set structures on muscular hypertrophy and performance after high-load resistance training manipulating the bench press exercise. Twenty-one recreationally trained subjects (12 men and 9 women) performed a 3-week familiarization phase and were then randomized into one of two 8-week upper-body and lower-body split programs occurring over 3 and then progressing to 4 sessions per week. Subjects performed 4 sets of 5 repetitions at 85% one repetition maximum (1RM) using a traditional-set structure (TRAD, n = 10), which involved 5 minutes of interset rest only, or a cluster-set structure, which included 30-second inter-repetition rest and 3 minutes of interset rest (CLUS, n = 11). A 1RM bench press, repetitions to failure at 70% 1RM, regional muscle thickness, and dual-energy x-ray absorptiometry were used to estimate changes in muscular strength, local muscular endurance, regional muscular hypertrophy, and body composition, respectively. Velocity loss was assessed using a linear position transducer at the intervention midpoint. TRAD demonstrated a significantly greater velocity loss magnitude (g = 1.50) and muscle thickness of the proximal pectoralis major (g = -0.34) compared with CLUS. There were no significant differences between groups for the remaining outcomes, although a small effect size favoring TRAD was observed for the middle region of the pectoralis major (g = -0.25). It seems that the greater velocity losses during sets observed in traditional-set compared with cluster-set structures may promote superior muscular hypertrophy within specific regions of the pectoralis major in recreationally trained subjects.

17.
Medicina (Kaunas) ; 57(7)2021 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-34203123

RESUMEN

This exploratory clinical case report presents an 87-year-old man who began bodybuilding at the age of 76 years and was officially recognised as the world's oldest competitive bodybuilder, competing until age 83. He has a background of complex health conditions including polio, strokes, cardiac arrest, atrial fibrillation, prostate disease, osteoarthritis, depression, bowel obstruction, reflux, and bladder cancer. Assessments of body composition, bone density, muscle performance, and diet-related practices were performed. The bodybuilder had superior fat-free mass, lower fat mass, and generally greater muscle performance compared to untrained healthy males of a similar age. Commencement of bodybuilding in older age appears to be possible, even with ongoing complex health conditions, and the potential benefits of this practice require systematic investigation in the future.


Asunto(s)
Composición Corporal , Somatotipos , Anciano , Anciano de 80 o más Años , Densidad Ósea , Humanos , Masculino , Fuerza Muscular
18.
Phys Rev Lett ; 125(12): 121601, 2020 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-33016765

RESUMEN

We define a class of machine-learned flow-based sampling algorithms for lattice gauge theories that are gauge invariant by construction. We demonstrate the application of this framework to U(1) gauge theory in two spacetime dimensions, and find that, at small bare coupling, the approach is orders of magnitude more efficient at sampling topological quantities than more traditional sampling procedures such as hybrid Monte Carlo and heat bath.

19.
J Gen Intern Med ; 35(Suppl 2): 839-848, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33107004

RESUMEN

BACKGROUND: Collaborative models for depression have not been widely adopted throughout the USA, possibly because there are no successful roadmaps for implementing these types of models. OBJECTIVE: To provide such a roadmap through a case study of the institutionalization of a depression care management (DCM) initiative for adult depression in a large healthcare system serving over 300,000 adults with depression. DESIGN: A retrospective observational program evaluation. Program evaluation results are presented for those patients enrolled in the initiative from January 1, 2015, to December 31, 2018. PARTICIPANTS: Over a 4-year period, 17,052 patients were treated in the DCM program. In general, participants were women (76%), were Hispanic (47%), spoke English (84%), and were 51.1 ± 18.3 years old, the majority of whom were 30-64 years old (57%). INTERVENTION: The collaborative care portion of the DCM initiative (DCM program) was implemented by a collaborative care team containing a treatment specialist, an assessment specialist, administrative staff, a primary care physician, and a psychiatry physician. MAIN MEASURES: The main outcome measures were total score on the 9-item Patient Health Questionnaire (PHQ-9). Outcomes were improvement (defined as at least 50% reduction in symptoms) and remission (defined as a PHQ-9 less than 5) of depression symptoms. Follow-up of depression symptoms was also collected at 6 months following discharge. KEY RESULTS: The average course of treatment in 2018, after full implementation, was 4.6 ± 3.0 months; 62% of patients experienced improvement in symptoms, and 45% experienced remission of their depression at the time of discharge. These rates were maintained at the 6-month follow-up. CONCLUSIONS: Collaborative care for depression can be institutionalized in large healthcare systems and be sustained with a specific, detailed roadmap that includes workflows, training, treatment guidelines, and clear documentation standards that are linked to performance metrics. Extensive stakeholder engagement at every level is also critical for success.


Asunto(s)
Prestación Integrada de Atención de Salud , Médicos de Atención Primaria , Adulto , Anciano , Depresión/diagnóstico , Depresión/epidemiología , Depresión/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Atención Primaria de Salud , Estudios Retrospectivos
20.
J Strength Cond Res ; 34(10): 2734-2742, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31009433

RESUMEN

Davies, TB, Halaki, M, Orr, R, Helms, ER, and Hackett, DA. Changes in bench press velocity and power after 8 weeks of high-load cluster- or traditional-set structures. J Strength Cond Res 34(10): 2734-2742, 2020-This study investigated the effects of high-load cluster- vs. traditional-set structures using the bench press on velocity and power. Twenty-one resistance-trained individuals (male = 12, female = 9) performed a 3-week familiarization block followed by randomization into 1 of 2 upper- and lower-body split training routines performed for 8 weeks. The bench press was the only exercise manipulated with subjects using either cluster-set (CLUS, n = 11) or traditional-set (TRAD, n = 10) structures during training sessions. Subjects performed 4 sets of 5 repetitions at 85% 1 repetition maximum (1RM) with CLUS having a 30-second inter-repetition, and 3-minute interset rest while TRAD had a 5-minute interset rest. A load-velocity profile of relative loads derived from a 1RM test was used to assess velocity and power (absolute and relative to body mass) on the bench press. Significant improvements over time were found across various loads ranging from 45 to 75% 1RM for absolute and relative peak power (p = 0.006-0.041), and mean power (p = 0.001-0.032). Significant decreases over time were found at 55% 1RM and 65% 1RM for peak velocity (p = 0.027 and p = 0.012, respectively) and mean velocity (p = 0.047 and p = 0.022, respectively). There were no significant group or group by time interactions found for all outcomes. Within the context of high-load resistance training, set structure seems to be of less importance for changes in bench press velocity and power provided there is an intention to lift with maximal concentric velocity.


Asunto(s)
Músculo Esquelético/fisiología , Entrenamiento de Fuerza/métodos , Adulto , Femenino , Humanos , Masculino , Fuerza Muscular , Adulto Joven
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