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1.
J Clin Anesth ; 86: 111053, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36736208

RESUMO

The optimal package of components for a prehabilitation intervention remains unclear. The aim was to determine the efficacy of supervised exercise prehabilitation programs to enhance patient fitness and improve surgical outcomes. The protocol was preregistered (PROSPERO: CRD42020180693). PubMed, MEDLINE, CINAHL, AMED, CENTRAL, PeDro, ClinicalTrials.gov and the WHO International Clinical Trials Registry were searched. Randomized controlled trials (RCTs) of supervised prehabilitation programs before major abdominal surgery were included. Physical function, cardiorespiratory capacity and surgical outcomes were the primary outcomes measures. Risk of bias was assessed according to the Cochrane Risk of Bias 1.0 tool for RCTs. Data are summarized narratively, and where possible, quantitavely. Meta-analyses results are reported as risk ratios (RR), mean difference of changes between baseline and follow-up time points or mean difference between groups and 95% confidence interval (CI). Twenty RCTs were included in the analysis with a total of 1258 patients. The average 6-min walking distance change was +33 m in the prehabilitation group compared to the usual care (UC) group after prehabilitation (95% CI: [13, 53], P < 0.01). Only in studies with more than one supervised session per week changes in 6-min-walk distance were significantly higher in the prehabilitation group compared to the UC group after prehabiliatation (Mean difference: 47 m, 95% [CI]: [20-75], P < 0.01). The change in peak volume of oxygen uptake during a maximum cardiopulmonary test was +1.47 mL·kg-1·min-1 in the prehabilitation group compared to the UC group (95% CI: [0.68, 2.25], P < 0.01). There was no significant difference in the change in oxygen uptake at anaerobic threshold between groups (Mean differences: 0.47, 95% CI: [-0.16, 1.10], P:0.14). Post-operative complications incidence was similar between groups (RR: 0.80, 95% CI: [0.61, 1.05], P:0.11), irrespective of the frequency of supervised session per week (RR: 0.67, 95% CI: [0.43, 1.03], P:0.07). In conclusion, prehabilitation programmes with more than one supervised session per week improved physical function but did not enhance surgical outcomes.


Assuntos
Exercício Físico , Exercício Pré-Operatório , Humanos , Abdome/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Oxigênio
2.
PLoS One ; 17(10): e0276009, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36264901

RESUMO

OBJECTIVE: To determine cardiorespiratory fitness and neuromuscular function of people with CFS and FMS compared to healthy individuals. DESIGN: Systematic review and meta-analysis. DATA SOURCES: PubMed, Medline, CINAHL, AMED, Cochrane Central Register of Controlled Trials (CENTRAL), and PEDro from inception to June 2022. ELIGIBLE CRITERIA FOR SELECTING STUDIES: Studies were included if presenting baseline data on cardiorespiratory fitness and/or neuromuscular function from observational or interventional studies of patients diagnosed with FMS or CFS. Participants were aged 18 years or older, with results also provided for healthy controls. Risk of bias assessment was conducted using the Quality Assessment Tool for Quantitative Studies (EPHPP). RESULTS: 99 studies including 9853 participants (5808 patients; 4405 healthy controls) met our eligibility criteria. Random effects meta-analysis showed lower cardiorespiratory fitness (VO2max, anaerobic threshold, peak lactate) and neuromuscular function (MVC, fatigability, voluntary activation, muscle volume, muscle mass, rate of perceived exertion) in CFS and FMS compared to controls: all with moderate to high effect sizes. DISCUSSION: Our results demonstrate lower cardiorespiratory fitness and muscle function in those living with FMS or CFS when compared to controls. There were indications of dysregulated neuro-muscular interactions including heightened perceptions of effort, reduced ability to activate the available musculature during exercise and reduced tolerance of exercise. TRAIL REGISTRATION: PROSPERO registration number: (CRD42020184108).


Assuntos
Aptidão Cardiorrespiratória , Síndrome de Fadiga Crônica , Fibromialgia , Humanos , Exercício Físico , Lactatos
3.
J Appl Physiol (1985) ; 133(4): 945-958, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35981730

RESUMO

This study aims to test the separated and combined effects of mechanoreflex activation and nociception through exercise-induced muscle damage (EIMD) on central and peripheral hemodynamics before and during single passive leg movement (sPLM). Eight healthy young males undertook four experimental sessions, in which a sPLM was performed on the dominant limb while in each specific session the contralateral was: 1) in a resting condition (CTRL), 2) stretched (ST), 3) resting after EIMD called delayed onset muscle soreness (DOMS) condition, or 4) stretched after EIMD (DOMS + ST). EIMD was used to induce DOMS in the following 24-48 h. Femoral blood flow (FBF) was assessed using Doppler ultrasound whereas central hemodynamics were assessed via finger photoplethysmography. Leg vascular conductance (LVC) was calculated as FBF/mean arterial pressure (MAP). RR-intervals were analyzed in the time (root mean squared of successive intervals; RMSSD) and frequency domain [low frequency (LF)/high frequency (HF)]. Blood samples were collected before each condition and gene expression analysis showed increased fold changes for P2X4 and IL1ß in DOMS and DOMS + ST compared with baseline. Resting FBF and LVC were decreased only in the DOMS + ST condition (-26 mL/min and -50 mL/mmHg/min respectively) with decreased RMSSD and increased LF/HF ratio. MAP, HR, CO, and SV were increased in ST and DOMS + ST compared with CTRL. Marked decreases of Δpeaks and AUC were observed for FBF (Δ: -146 mL/min and -265 mL respectively) and LVC (Δ: -8.66 mL/mmHg/min and ±1.7 mL/mmHg/min respectively) all P < 0.05. These results suggest that the combination of mechanoreflex and nociception resulted in decreased vagal tone and concomitant rise in sympathetic drive that led to increases in resting central hemodynamics with reduced limb blood flow before and during sPLM.NEW & NOTEWORTHY Exercise-induced muscle damage (EIMD) is a well-known model to study mechanical hyperalgesia and muscle peripheral nerve sensitizations. The combination of static stretching protocol on the damaged limb extensively increases resting central hemodynamics with reduction in resting limb blood flow and passive leg movement-induced hyperemia. The mechanism underlining these results may be linked to reduction of vagal tone with concomitant increase in sympathetic activity following mechano- and nociceptive activation.


Assuntos
Hiperemia , Nociceptividade , Cafeína , Hemodinâmica/fisiologia , Humanos , Masculino , Movimento/fisiologia , Músculo Esquelético/fisiologia , Músculos , Mialgia , Fluxo Sanguíneo Regional/fisiologia
4.
Eur J Appl Physiol ; 122(1): 211-221, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34652528

RESUMO

BACKGROUND: An exaggerated exercise blood pressure (BP) is associated with a reduced exercise capacity. However, its connection to physical performance during competition is unknown. AIM: To examine BP responses to ischaemic handgrip exercise in Master athletes (MA) with and without underlying morbidities and to assess their association with athletic performance during the World Master Track Cycling Championships 2019. METHODS: Forty-eight Master cyclists [age 59 ± 13yrs; weekly training volume 10.4 ± 4.1 h/week; handgrip maximum voluntary contraction (MVC) 46.3 ± 11.5 kg] divided into 2 matched groups (24 healthy MA and 24 MA with morbidity) and 10 healthy middle-aged non-athlete controls (age 48.3 ± 8.3 years; MVC 40.4 ± 14.8 kg) performed 5 min of forearm occlusion including 1 min handgrip isometric contraction (40%MVC) followed by 5 min recovery. Continuous beat-by-beat BP was recorded using finger plethysmography. Age-graded performance (AGP) was calculated to compare race performances among MA. Healthy Master cyclists were further grouped into middle-age (age 46.2 ± 6.4 years; N:12) and old-age (age 65.0 ± 7.7 years; N:12) for comparison with middle-aged non-athlete controls. RESULTS: Healthy and morbidity MA groups showed similar BP responses during forearm occlusion and AGP (90.1 ± 4.3% and 91.0 ± 5.3%, p > 0.05, respectively). Healthy and morbidity MA showed modest correlation between the BP rising slope for 40%MVC ischaemic exercise and AGP (r = 0.5, p < 0.05). MA showed accelerated SBP recovery after cessation of ischaemic handgrip exercise compared to healthy non-athlete controls. CONCLUSION: Our findings associate long-term athletic training with improved BP recovery following ischaemic exercise regardless of age or reported morbidity. Exaggerated BP in Master cyclists during ischaemic exercise was associated with lower AGP during the World Master Cycling Championships.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Força da Mão/fisiologia , Hipertensão/etiologia , Hipertensão/fisiopatologia , Resistência Física/fisiologia , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade
5.
Eur J Appl Physiol ; 121(12): 3447-3457, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34515866

RESUMO

PURPOSE: Respiratory and musculoskeletal function decline with age, irrespective of physical activity levels. Previous work has suggested that the age-related rate of decline in function of these two systems might be similar, but it is not known to what extent each system contributes to decreasing performance in ageing master cyclists. Therefore, the purposes of this study are (1) whether the age-related rate of decline in respiratory function, respiratory muscle strength, muscle architecture, muscle function, haemoglobin concentration, haematocrit and performance in master cyclists is uniform and (2) which parameters contribute most to the reduction in performance with age. METHODS: Master cyclists were recruited during the Track Cycling Masters World Championship 2019 in Manchester. Respiratory function and respiratory muscle strength were determined using spirometry and a mouth pressure device, respectively. Muscle architecture was determined using ultrasonography, and muscle function by countermovement jump. RESULTS: Forced expiratory volume in the first second, forced vital capacity, fascicle length, muscle thickness, take-off velocity, jump power, jump power per body mass, handgrip strength, haemoglobin concentration and performance correlated negatively with age (p ≤ 0.043). The age-related rate of decline did not differ significantly between parameters (p = 0.124), but it was slower for haemoglobin concentration (p = 0.041). Take-off velocity was the major determinant of performance in 200, 500 and 2000 m track cycling disciplines (R2adj = 0.675, 0.786 and 0.769, respectively; p < 0.001). CONCLUSION: Age-related decline in respiratory and muscle system is accompanied by a similar rate of decline in performance. The major contribution to the age-related decline of performance is reduced muscle function, specifically take-off velocity.


Assuntos
Envelhecimento/fisiologia , Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Força Muscular/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória
6.
J Strength Cond Res ; 35(1): 64-71, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29533360

RESUMO

ABSTRACT: Bagley, L, Al-Shanti, N, Bradburn, S, Baig, O, Slevin, M, and McPhee, JS. Sex comparison of knee extensor size, strength, and fatigue adaptation to sprint interval training. J Strength Cond Res 35(1): 64-71, 2021-Regular sprint interval training (SIT) improves whole-body aerobic capacity and muscle oxidative potential, but very little is known about knee extensor anabolic or fatigue resistance adaptations, or whether effects are similar for men and women. The purpose of this study was to compare sex-related differences in knee extensor size, torque-velocity relationship, and fatigability adaptations to 12-week SIT. Sixteen men and 15 women (mean [SEM] age: 41 [±2.5] years) completed measurements of total body composition assessed by dual energy X-ray absorptiometry, quadriceps muscle cross-sectional area (CSAQ) assessed by magnetic resonance imaging, the knee extensor torque-velocity relationship (covering 0-240°·s-1) and fatigue resistance, which was measured as the decline in torque from the first to the last of 60 repeated concentric knee extensions performed at 180°·s-1. Sprint interval training consisted of 4 × 20-second sprints on a cycle ergometer set at an initial power output of 175% of power at V̇o2max, 3 times per week for 12 weeks. Quadriceps muscle cross-sectional area increased by 5% (p = 0.023) and fatigue resistance improved 4.8% (p = 0.048), with no sex differences in these adaptations (sex comparisons: p = 0.140 and p = 0.282, respectively). Knee extensor isometric and concentric torque was unaffected by SIT in both men and women (p > 0.05 for all velocities). Twelve-week SIT, totaling 4 minutes of very intense cycling per week, significantly increased fatigue resistance and CSAQ similarly in men and women, but did not significantly increase torque in men or women. These results suggest that SIT is a time-effective training modality for men and women to increase leg muscle size and fatigue resistance.


Assuntos
Treinamento Intervalado de Alta Intensidade , Adulto , Feminino , Humanos , Joelho , Articulação do Joelho/diagnóstico por imagem , Masculino , Fadiga Muscular , Força Muscular , Músculo Esquelético , Torque
7.
Scand J Med Sci Sports ; 29(6): 791-799, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30742335

RESUMO

Lower physical activity levels in old age are thought to contribute to the age-related decline in peak aerobic and anaerobic power. Master athletes maintain high levels of physical activity with advancing age and endurance or power training may influence the extent to which these physical functions decline with advancing age. To investigate, 37-90-year-old power (n = 20, 45% female) and endurance (n = 19, 58% female) master athletes were recruited. Maximal aerobic power was assessed when cycling two-legged (VO2 Peak2-leg ) and cycling one-legged (VO2 Peak1-leg ), while peak jumping (anaerobic) power was assessed by a countermovement jump. Men and women had a similar VO2 Peak2-leg (mL/kg/min, P = 0.138) and similar ratio of VO2 Peak1-leg to VO2 Peak2-leg (P = 0.959) and similar ratio of peak aerobic to anaerobic power (P = 0.261). The VO2 Peak2-leg (mL/kg/min) was 17% (P = 0.022) and the peak rate of fat oxidation (FATmax) during steady-state cycling was 45% higher in endurance than power athletes (P = 0.001). The anaerobic power was 33% higher in power than endurance athletes (P = 0.022). The VO2 Peak1-leg :VO2 Peak2-leg ratio did not differ significantly between disciplines, but the aerobic to anaerobic power ratio was 40% higher in endurance than power athletes (P = 0.002). Anaerobic power, VO2 Peak2-leg , VO2 Peak1-leg , and power at FATmax decreased by around 7%-14% per decade in male and female power and endurance athletes. The cross-sectional data from 37-90-year-old master athletes in the present study indicate that peak anaerobic and aerobic power decline by around 7%-14% per decade and this does not differ between athletic disciplines or sexes.


Assuntos
Envelhecimento , Atletas , Força Muscular , Consumo de Oxigênio , Aptidão Física , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Teste de Esforço , Feminino , Humanos , Metabolismo dos Lipídeos , Masculino , Pessoa de Meia-Idade , Resistência Física
8.
Neurobiol Aging ; 63: 54-64, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29223680

RESUMO

Chronic low-grade inflammation during aging (inflammaging) is associated with cognitive decline and neurodegeneration; however, the mechanisms underlying inflammaging are unclear. We studied a population (n = 361) of healthy young and old adults from the MyoAge cohort. Peripheral levels of C-X-C motif chemokine ligand 10 (CXCL10) was found to be higher in older adults, compared with young, and negatively associated with working memory performance. This coincided with an age-related reduction in blood DNA methylation at specific CpGs within the CXCL10 gene promoter. In vitro analysis supported the role of DNA methylation in regulating CXCL10 transcription. A polymorphism (rs56061981) that altered methylation at one of these CpG sites further associated with working memory performance in 2 independent aging cohorts. Studying prefrontal cortex samples, we found higher CXCL10 protein levels in those with Alzheimer's disease, compared with aged controls. These findings support the association of peripheral inflammation, as demonstrated by CXCL10, in aging and cognitive decline. We reveal age-related epigenetic and genetic factors which contribute to the dysregulation of CXCL10.


Assuntos
Envelhecimento/genética , Envelhecimento/metabolismo , Córtex Cerebral/metabolismo , Quimiocina CXCL10/metabolismo , Cognição/fisiologia , Memória/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/patologia , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Estudos de Coortes , Metilação de DNA , Epigênese Genética , Feminino , Células HeLa , Humanos , Inflamação/genética , Inflamação/metabolismo , Masculino , Degeneração Neural , Células U937 , Adulto Jovem
9.
BMJ Open Sport Exerc Med ; 2(1): e000056, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27900150

RESUMO

BACKGROUND: The purpose of this study was to examine whether very short duration, very high intensity sprint interval training (SIT) leads to loss of body fat mass in association with improvements to VO2max and fatty acid oxidation, and to assess the extent of sex dimorphism in these physiological responses. METHODS: A total of 24 men and 17 women (mean (SEM) age: 39 (±2) years; body mass index 24.6 (0.6)) completed measurements of the maximal rate of oxygen uptake (VO2max) and fatty acid oxidation (FATmax). Body fat and lean mass were measured by dual emission x-ray absorptiometry, and fasting blood lipid, glucose and insulin profiles were assessed before and after training. SIT consisted of 4×20 s sprints on a cycle ergometer at approximately 175% VO2max, three times per week for 12 weeks. RESULTS: Fat mass decreased by 1.0 kg, although men lost statistically significantly more fat than women both when expressed in Kg and as % body fat. VO2max increased by around 9%, but women improved VO2max significantly more than men. FATmax improved by around 13%, but fasting plasma glucose, insulin, total triglyceride, total cholesterol and high-density lipoprotein (HDL) did not change after training, while low-density lipoprotein decreased by 8% (p=0.028) and the HDL:Total Cholesterol ratio improved by 6%. There were no sex differences in these metabolic responses to training. CONCLUSIONS: These results show lower body fat %, and higher rates of fatty acid oxidation and VO2max after 12 weeks of training for just 4 min per week. Notably, women improved VO2max more than men, while men lost more fat than women.

10.
Age Ageing ; 45(6): 844-849, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27515675

RESUMO

INTRODUCTION: cognitive deterioration and reductions of bone health coincide with increasing age. We examine the relationship between bone composition and plasma markers of bone remodelling with measures of cognitive performance in healthy adults. METHODS: this cross-sectional study included 225 old (52% women, mean age: 74.4 ± 3.3 years) and 134 young (52% women, mean age: 23.4 ± 2.7 years) adult participants from the MyoAge project. Whole body bone mineral density was measured by dual-energy X-ray absorptiometry. Blood analyses included a panel of bone-related peptides (dickkopf-1, osteoprotegerin, osteocalcin (OC), osteopontin, sclerostin, parathyroid hormone and fibroblast growth factor 23), as well as serum calcium and 25-hydroxy vitamin D assays. A selection of cognitive domains (working memory capacity, episodic memory, executive functioning and global cognition) was assessed with a standardised neuropsychological test battery. RESULTS: adjusting for covariates and multiple testing revealed that plasma OC levels were positively associated with measures of executive functioning (ß = 0.444, P < 0.001) and global cognition (ß = 0.381, P = 0.001) in the older women. DISCUSSION: these correlative results demonstrate a positive association between OC, a factor known to regulate bone remodelling, with cognitive performance in older non-demented women. Further work should address possible mechanistic interpretations in humans.


Assuntos
Envelhecimento/sangue , Envelhecimento/psicologia , Doenças Ósseas Metabólicas/sangue , Transtornos Cognitivos/psicologia , Cognição , Envelhecimento Cognitivo/psicologia , Osteocalcina/sangue , Absorciometria de Fóton , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Densidade Óssea , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/epidemiologia , Remodelação Óssea , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Estudos Transversais , Europa (Continente) , Função Executiva , Feminino , Humanos , Masculino , Memória Episódica , Memória de Curto Prazo , Testes Neuropsicológicos , Fatores Sexuais , Adulto Jovem
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