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1.
Front Nutr ; 11: 1274356, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38840696

RESUMO

Background: The relationship between adiposity and pain is complex. Excess weight increases the risk for chronic musculoskeletal pain (CMP), driven by increased biomechanical load and low-grade systemic inflammation. Pain limits physical function, impacting energy balance contributing to weight gain. The primary aims of this study were to profile pain characteristics in participants with overweight or obesity and determine if weight loss through dietary-induced energy restriction, and presence of CMP, or magnitude of weight loss, was associated with changes in adiposity, pain, functional mobility, and inflammation. Methods: This was a secondary analysis of data from adults (25-65 years) with overweight or obesity (BMI 27.5-34.9 kg/m2) enrolled in a 3-month, 30% energy-restricted dietary intervention to induce weight loss (January 2019-March 2021). Anthropometric measures (weight, waist circumference and fat mass), pain prevalence, pain severity (McGill Pain Questionnaire, MPQ), pain intensity (Visual Analog Scale, VAS), functional mobility (timed up and go, TUG) and inflammation (high sensitivity C-Reactive Protein, hsCRP) were assessed at baseline and 3-months. Results: One hundred and ten participants completed the intervention and had weight and pain assessed at both baseline and 3-months. Participants lost 7.0 ± 0.3 kg, representing 7.9% ± 3.7% of body mass. At 3-months, functional mobility improved (TUG -0.2 ± 0.1 s, 95% CI -0.3, -0.1), but there was no change in hsCRP. Compared to baseline, fewer participants reported CMP at 3-months (n = 56, 51% to n = 27, 25%, p < 0.001) and presence of multisite pain decreased from 22.7% to 10.9% (p < 0.001). Improvements in anthropometric measures and functional mobility did not differ between those presenting with or without CMP at baseline. Improvements in pain were not related to the magnitude of weight loss. Conclusion: Weight loss was effective in reducing pain prevalence and improving functional mobility, emphasizing the importance of considering weight-loss as a key component of pain management. Clinical trial registration: identifier, ACTRN12618001861246.

2.
BMJ Open ; 14(1): e081664, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38272555

RESUMO

INTRODUCTION: Previous research has associated high dietary cholesterol intake with raised low-density lipoprotein cholesterol (LDL-C) and thus increased risk for cardiovascular disease (CVD). Emerging research suggests that it is saturated fat, not dietary cholesterol, associated with increased CVD risk. Despite being high in cholesterol, eggs, low in saturated fat, are not adversely associated with blood lipids or CVD risk. This paper describes a randomised controlled counter-balanced, cross-over trial assessing the effects of a high-cholesterol/low-saturated fat (egg) diet and a low-cholesterol/high-saturated fat diet (egg free) on blood lipids and lipoproteins, while accounting for physical activity levels which can also influence these parameters. The primary aim is to demonstrate that high cholesterol intake (from eggs) within a healthy, low-saturated fat diet does not adversely affect blood lipid levels and lipoprotein profiles. Instead, we propose that adverse effects on these parameters are mediated by saturated fat intake. The secondary aim is to explore relationships between changes in blood lutein and zeaxanthin concentrations and alterations in physical activity, examining whether changes in physical activity mediate effects on blood lipids and lipoproteins. METHODS AND ANALYSIS: Fifty-two adults aged 18-60 years with LDL-C less than 3.5 mmol/L will be randomly allocated to three isocaloric diets for 5 weeks each: a high-cholesterol (600 mg)/low-saturated fat (6%) (egg) diet, a low-cholesterol (300 mg)/high-saturated fat (12%) (egg free) diet and a control diet that is high in both cholesterol (600 mg) and saturated fat (12%). Lipid and lipoprotein levels, lipoprotein size and concentrations, blood pressure, blood glucose, physical activity levels, and plasma lutein and zeaxanthin concentrations will be measured. Treatment effects will be analysed using linear mixed effects models. ETHICS AND DISSEMINATION: Ethics approval was obtained from the University of South Australia Human Research Ethics Committee no. 204 327. Results will be disseminated through peer-reviewed journals and national and international presentations. TRIAL REGISTRATION NUMBER: NCT05267522.


Assuntos
Doenças Cardiovasculares , Hipercolesterolemia , Adulto , Humanos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Colesterol , LDL-Colesterol , Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/efeitos adversos , Ácidos Graxos/efeitos adversos , Lipídeos , Lipoproteínas , Luteína , Ensaios Clínicos Controlados Aleatórios como Assunto , Triglicerídeos , Zeaxantinas , Adolescente , Adulto Jovem , Pessoa de Meia-Idade
3.
Int J Sports Physiol Perform ; 19(2): 207-211, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37995677

RESUMO

PURPOSE: There are important methodological considerations for translating wearable-based gait-monitoring data to field settings. This study investigated different devices' sampling rates, signal lengths, and testing frequencies for athlete monitoring using dynamical systems variables. METHODS: Secondary analysis of previous wearables data (N = 10 runners) from a 5-week intensive training intervention investigated impacts of sampling rate (100-2000 Hz) and signal length (100-300 strides) on detection of gait changes caused by intensive training. Primary analysis of data from 13 separate runners during 1 week of field-based testing determined day-to-day stability of outcomes using single-session data and mean data from 2 sessions. Stride-interval long-range correlation coefficient α from detrended fluctuation analysis was the gait outcome variable. RESULTS: Stride-interval α reduced at 100- and 200- versus 300- to 2000-Hz sampling rates (mean difference: -.02 to -.08; P ≤ .045) and at 100- compared to 200- to 300-stride signal lengths (mean difference: -.05 to -.07; P < .010). Effects of intensive training were detected at 100, 200, and 400 to 2000 Hz (P ≤ .043) but not 300 Hz (P = .069). Within-athlete α variability was lower using 2-session mean versus single-session data (smallest detectable change: .13 and .22, respectively). CONCLUSIONS: Detecting altered gait following intensive training was possible using 200 to 300 strides and a 100-Hz sampling rate, although 100 and 200 Hz underestimated α compared to higher rates. Using 2-session mean data lowers smallest detectable change values by nearly half compared to single-session data. Coaches, runners, and researchers can use these findings to integrate wearable-device gait monitoring into practice using dynamic systems variables.


Assuntos
Corrida , Dispositivos Eletrônicos Vestíveis , Humanos , Marcha , Atletas , Fadiga , Fenômenos Biomecânicos
4.
J Alzheimers Dis ; 96(1): 409-427, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781806

RESUMO

BACKGROUND: Several clinical trials have examined diet and physical activity lifestyle changes as mitigation strategies for risk factors linked to cognitive decline and dementias such as Alzheimer's disease. However, the ability to modify these behaviors longer term, to impact cognitive health has remained elusive. OBJECTIVE: The MedWalk trial's primary aim is to investigate whether longer-term adherence to a Mediterranean-style diet and regular walking, delivered through motivational interviewing and cognitive-behavioral therapy (MI-CBT), can reduce age-associated cognitive decline and other dementia risk factors in older, independently living individuals without cognitive impairment. METHODS: MedWalk, a one-year cluster-randomized controlled trial across two Australian states, recruited 60-90-year-old people from independent living retirement villages and the wider community. Participants were assigned to either the MedWalk intervention or a control group (maintaining their usual diet and physical activity). The primary outcome is 12-month change in visual memory and learning assessed from errors on the Paired Associates Learning Task of the Cambridge Neuropsychological Test Automated Battery. Secondary outcomes include cognition, mood, cardiovascular function, biomarkers related to nutrient status and cognitive decline, MI-CBT effectiveness, Mediterranean diet adherence, physical activity, quality of life, cost-effectiveness, and health economic evaluation.Progress and Discussion:Although COVID-19 impacts over two years necessitated a reduced timeline and sample size, MedWalk retains sufficient power to address its aims and hypotheses. Baseline testing has been completed with 157 participants, who will be followed over 12 months. If successful, MedWalk will inform interventions that could substantially reduce dementia incidence and ameliorate cognitive decline in the community. TRIAL REGISTRATION: Registered on the Australia New Zealand Clinical Trials Registry ANZCTR 12620000978965 (https://www.anzctr.org.au).


Assuntos
COVID-19 , Disfunção Cognitiva , Demência , Dieta Mediterrânea , Humanos , Idoso , Idoso de 80 Anos ou mais , Qualidade de Vida , Austrália/epidemiologia , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/prevenção & controle , Caminhada , Cognição , Demência/epidemiologia , Demência/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Obesity (Silver Spring) ; 31(10): 2467-2481, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37621033

RESUMO

OBJECTIVE: This study evaluated weight and cardiometabolic outcomes after a 3-month energy-restricted diet (-30%) containing almonds (almond-enriched diet [AED]) or containing carbohydrate-rich snacks (nut-free control diet [NFD]) (Phase 1), followed by 6 months of weight maintenance (Phase 2). METHODS: Participants (25-65 years old) with overweight or obesity (BMI 27.5-34.9 kg/m2 ) were randomly allocated to AED (n = 68) or NFD (n = 72). RESULTS: Both groups lost weight during Phase 1 (p < 0.001) (mean [SE], -7.0 [0.5] kg AED vs. -7.0 [0.5] kg NFD, p = 0.858) and Phase 2 (p = 0.009) (-1.1 [0.5] kg AED vs. -1.3 [0.6] NFD, p = 0.756), with improvements in percentage lean mass after Phase 2 (4.8% [0.3%], p < 0.001). Reductions occurred in fasting glucose (-0.2 [0.07] mmol/L, p = 0.003), insulin (-8.1 [4.0] pmol/L, p = 0.036), blood pressure (-4.9 [0.8] mm Hg systolic, -5.0 [0.5] mm Hg diastolic, p < 0.001), total cholesterol (-0.3 [0.1] mmol/L), low-density lipoprotein (LDL) (-0.2 [0.1] mmol/L), very low-density lipoprotein (-0.1 [0.03] mmol/L), and triglycerides (-0.3 [0.06] mmol/L) (all p < 0.001), and high-density lipoprotein increased (0.1 [0.02] mmol/L, p = 0.011) by the end of Phase 2 in both groups. There were group by time interactions for lipoprotein particle concentrations: very small triglyceride-rich (-31.0 [7.7] nmol/L AED vs. -4.8 [7.9] nmol/L NFD, p = 0.007), small LDL (-109.3 [40.5] nmol/L AED vs. -20.7 [41.6] nmol/L NFD, p = 0.017), and medium LDL (-24.4 [43.4] nmol/L AED vs. -130.5 [44.4] nmol/L NFD, p = 0.045). CONCLUSIONS: An energy-restricted AED resulted in weight loss and weight loss maintenance comparable to an energy-restricted NFD, and both diets supported cardiometabolic health. The AED resulted in greater improvements in some lipoprotein subfractions, which may enhance reductions in cardiovascular risk.


Assuntos
Doenças Cardiovasculares , Prunus dulcis , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Lanches , Glucose , Lipoproteínas LDL , Doenças Cardiovasculares/prevenção & controle
6.
Curr Atheroscler Rep ; 25(7): 373-380, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37219706

RESUMO

PURPOSE OF REVIEW: This review summarizes recent evidence published since a previous review in 2018 on the association between egg consumption and risk of cardiovascular disease (CVD) mortality, CVD incidence, and CVD risk factors. RECENT FINDINGS: No recent randomized controlled trials were identified. Evidence from observational studies is mixed, with studies reporting either an increased risk or no association of highest egg consumption with CVD mortality, and a similar spread of increased risk, decreased risk, or no association between egg intake and total CVD incidence. Most studies reported a reduced risk or no association between egg consumption and CVD risk factors. Included studies reported low and high egg intake as between 0 and 1.9 eggs/week and 2 and ≥14 eggs/week, respectively. Ethnicity may influence the risk of CVD with egg consumption, likely due to differences in how eggs are consumed in the diet rather than eggs themselves. Recent findings are inconsistent regarding the possible relationship between egg consumption and CVD mortality and morbidity. Dietary guidance should focus on improving the overall quality of the diet to promote cardiovascular health.


Assuntos
Doenças Cardiovasculares , Humanos , Fatores de Risco , Doenças Cardiovasculares/etiologia , Dieta
7.
Eur J Sport Sci ; 23(9): 1859-1867, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36404735

RESUMO

This study evaluated relationships between changes in training load, haematological responses, and endurance exercise performance during temperate and heat acclimation (HA) training preceding a male team cycling pursuit world record (WR). Haemoglobin mass (Hbmass) and concentration ([Hb]), plasma volume (PV) and blood volume (BV) were assessed in nine male track endurance cyclists (∼3 occasions per month) training in temperate conditions (247-142 days prior to the WR) to establish responses to differing acute (ATL) and chronic (CTL) training loads. Testing was performed again pre- and post-HA (22-28 days prior to the WR). Endurance performance (V̇O2max, 4MMP, lactate threshold 1 and 2) was assessed on three occasions (238-231, 189-182 and 133-126 days prior to the WR). In temperate conditions, CTL was associated with Hbmass (B = 0.62, P = 0.02), PV (B = 4.49, P = 0.01) and BV (B = 6.51, P = 0.04) but not [Hb] (B = -0.01, P = 0.17). ATL was associated with PV (B = 2.28, P < 0.01), BV (B = 2.63, P = 0.04) and [Hb] (B = -0.01, P = 0.04) but not Hbmass (B = 0.10, P = 0.41). During HA, PV increased 8.2% (P < 0.01), while Hbmass, CTL and ATL were unchanged. Hbmass and [Hb] were associated with all performance outcomes (P < 0.05), except V̇O2max. PV and BV were not associated with performance outcomes. During temperate training, changes in Hbmass were most strongly associated with changes in CTL. Both CTL and ATL were associated with changes in PV, but HA was associated with increased PV and maintenance of Hbmass without increasing ATL or CTL. In practical terms, maintaining high CTL and high Hbmass might be beneficial for improving endurance performance.HIGHLIGHTSChanges in haemoglobin mass were associated with endurance exercise performance and changes in chronic training load in temperate conditions.Heat acclimation increased plasma volume and maintained haemoglobin mass independently of chronic training load.Chronic training loads and haemoglobin mass should be increased to improve endurance exercise performance.Heat acclimation may optimise haematological adaptations when training load is reduced.


Assuntos
Volume Sanguíneo , Temperatura Alta , Humanos , Masculino , Volume Sanguíneo/fisiologia , Volume Plasmático , Hemoglobinas/análise , Aclimatação
8.
Sports Med ; 53(3): 687-705, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36527593

RESUMO

BACKGROUND: Studies investigating the effects of common recovery modalities following acute strenuous exercise have reported mixed results. OBJECTIVES: This systematic review with meta-analysis and meta-regression compared the effects of cold-water immersion (CWI) against other common recovery modalities on recovery of athletic performance, perceptual outcomes, and creatine kinase (CK) following acute strenuous exercise in physically active populations. STUDY DESIGN: Systematic review, meta-analysis, and meta-regression. METHODS: The MEDLINE, SPORTDiscus, Scopus, Web of Science, Cochrane Library, EmCare, and Embase databases were searched up until September 2022. Studies were included if they were peer reviewed, published in English, included participants who were involved in sport or deemed physically active, compared CWI with other recovery modalities following an acute bout of strenuous exercise, and included measures of performance, perceptual measures of recovery, or CK. RESULTS: Twenty-eight studies were meta-analysed. CWI was superior to other recovery methods for recovering from muscle soreness, and similar to other methods for recovery of muscular power and flexibility. CWI was more effective than active recovery, contrast water therapy and warm-water immersion for most recovery outcomes. Air cryotherapy was significantly more effective than CWI for the promotion of recovery of muscular strength and the immediate recovery of muscular power (1-h post-exercise). Meta-regression revealed that water temperature and exposure duration were rarely exposure moderators. CONCLUSION: CWI is effective for promoting recovery from acute strenuous exercise in physically active populations compared with other common recovery methods. PROTOCOL REGISTRATION: Open Science Framework: https://doi.org/10.17605/OSF.IO/NGP7C.


Assuntos
Desempenho Atlético , Temperatura Baixa , Humanos , Imersão , Mialgia/terapia , Água , Creatina Quinase
9.
Eur J Nutr ; 62(2): 857-866, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36305961

RESUMO

PURPOSE: Early satiety has been identified as one of the mechanisms that may explain the beneficial effects of nuts for reducing obesity. This study compared postprandial changes in appetite-regulating hormones and self-reported appetite ratings after consuming almonds (AL, 15% of energy requirement) or an isocaloric carbohydrate-rich snack bar (SB). METHODS: This is a sub-analysis of baseline assessments of a larger parallel-arm randomised controlled trial in overweight and obese (Body Mass Index 27.5-34.9 kg/m2) adults (25-65 years). After an overnight fast, 140 participants consumed a randomly allocated snack (AL [n = 68] or SB [n = 72]). Appetite-regulating hormones and self-reported appetite sensations, measured using visual analogue scales, were assessed immediately before snack food consumption, and at 30, 60, 90 and 120 min following snack consumption. A sub-set of participants (AL, n = 49; SB, n = 48) then consumed a meal challenge buffet ad libitum to assess subsequent energy intake. An additional appetite rating assessment was administered post buffet at 150 min. RESULTS: Postprandial C-peptide area under the curve (AUC) response was 47% smaller with AL compared to SB (p < 0.001). Glucose-dependent insulinotropic polypeptide, glucagon and pancreatic polypeptide AUC responses were larger with AL compared to SB (18%, p = 0.005; 39% p < 0.001; 45% p < 0.001 respectively). Cholecystokinin, ghrelin, glucagon-like peptide-1, leptin and polypeptide YY AUCs were not different between groups. Self-reported appetite ratings and energy intake following the buffet did not differ between groups. CONCLUSION: More favourable appetite-regulating hormone responses to AL did not translate into better self-reported appetite or reduced short-term energy consumption. Future studies should investigate implications for longer term appetite regulation. ANZCTR REFERENCE NUMBER: ACTRN12618001861246 2018.


Assuntos
Apetite , Prunus dulcis , Adulto , Humanos , Apetite/fisiologia , Lanches , Autorrelato , Insulina , Saciação/fisiologia , Grelina , Obesidade , Ingestão de Energia , Sensação , Carboidratos , Período Pós-Prandial
10.
Artigo em Inglês | MEDLINE | ID: mdl-35742343

RESUMO

Chronic food insecurity persists in high-income countries, leading to an entrenched need for food relief. In Australia, food relief services primarily focus on providing food to meet immediate need. To date, there has been few examples of a vision in the sector towards client outcomes and pathways out of food insecurity. In 2016, the South Australian Government commissioned research and community sector engagement to identify potential policy actions to address food insecurity. This article describes the process of developing a co-designed South Australian Food Relief Charter, through policy-research-practice collaboration, and reflects on the role of the Charter as both a policy tool and a declaration of a shared vision. Methods used to develop the Charter, and resulting guiding principles, are discussed. This article reflects on the intentions of the Charter and suggests how its guiding principles may be used to guide collective actions for system improvement. Whilst a Charter alone may be insufficient to create an integrated food relief system that goes beyond the provision of food, it is a useful first step in enabling a culture where the sector can have a unified voice to advocate for the prevention of food insecurity.


Assuntos
Assistência Alimentar , Abastecimento de Alimentos , Austrália , Insegurança Alimentar , Humanos , Austrália do Sul
11.
Am J Mens Health ; 16(2): 15579883221084493, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35300537

RESUMO

Although sport participation is intrinsically motivating and improves the physical health of middle-aged men, its influence on subjective health measures, such as health-related quality of life, self-rated health, or well-being is unclear. The purpose of this scoping review was to describe the existing literature that has assessed male sport participants and their subjective health. MEDLINE, Embase, Emcare, PsycInfo, SPORTDiscus, Cochrane Library, and Web of Science were searched, and reference lists of included studies were pearled. Included were original peer-reviewed studies reporting a marker of subjective health in males, 35 to 54 years (average), who participated in sport. The search identified 21 eligible articles, 18 quantitative, 2 mixed-methods, and 1 qualitative, from 13 different countries. Eighteen studies were cross-sectional. A broad range of outcomes were assessed, with the most common being quality of life/health-related quality of life (n = 6) and self-rated health (n = 6). Most studies assessing quality of life, health-related quality of life, or self-rated health demonstrated a positive association with sport participation, while sport participation was not related to measures of life satisfaction, flourishing, happiness or global well-being; however, limited studies examined these latter outcomes. Sport participation appears to be related to better select subjective health outcomes in middle-aged men. However, most available data are cross-sectional and thus causation cannot be determined. Randomized intervention trials are required to determine whether sport participation improves the subjective health of middle-aged men.Open Science Framework registration: https://osf.io/zypds.


Assuntos
Qualidade de Vida , Esportes , Felicidade , Humanos , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa
12.
Sports Med ; 52(7): 1667-1688, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35157264

RESUMO

BACKGROUND: Studies investigating the effects of cold-water immersion (CWI) on the recovery of athletic performance, perceptual measures and creatine kinase (CK) have reported mixed results in physically active populations. OBJECTIVES: The purpose of this systematic review was to investigate the effects of CWI on recovery of athletic performance, perceptual measures and CK following an acute bout of exercise in physically active populations. STUDY DESIGN: Systematic review with meta-analysis and meta-regression. METHODS: A systematic search was conducted in September 2021 using Medline, SPORTDiscus, Scopus, Web of Science, Cochrane Library, EmCare and Embase databases. Studies were included if they were peer reviewed and published in English, included participants who were involved in sport or deemed physically active, compared CWI with passive recovery methods following an acute bout of strenuous exercise and included athletic performance, athlete perception and CK outcome measures. Studies were divided into two strenuous exercise subgroups: eccentric exercise and high-intensity exercise. Random effects meta-analyses were used to determine standardised mean differences (SMD) with 95% confidence intervals. Meta-regression analyses were completed with water temperature and exposure durations as continuous moderator variables. RESULTS: Fifty-two studies were included in the meta-analyses. CWI improved the recovery of muscular power 24 h after eccentric exercise (SMD 0.34 [95% CI 0.06-0.62]) and after high-intensity exercise (SMD 0.22 [95% CI 0.004-0.43]), and reduced serum CK (SMD - 0.85 [95% CI - 1.61 to - 0.08]) 24 h after high-intensity exercise. CWI also improved muscle soreness (SMD - 0.89 [95% CI - 1.48 to - 0.29]) and perceived feelings of recovery (SMD 0.66 [95% CI 0.29-1.03]) 24 h after high-intensity exercise. There was no significant influence on the recovery of strength performance following either eccentric or high-intensity exercise. Meta-regression indicated that shorter time and lower temperatures were related to the largest beneficial effects on serum CK (duration and temperature dose effects) and endurance performance (duration dose effects only) after high-intensity exercise. CONCLUSION: CWI was an effective recovery tool after high-intensity exercise, with positive outcomes occurring for muscular power, muscle soreness, CK, and perceived recovery 24 h after exercise. However, after eccentric exercise, CWI was only effective for positively influencing muscular power 24 h after exercise. Dose-response relationships emerged for positively influencing endurance performance and reducing serum CK, indicating that shorter durations and lower temperatures may improve the efficacy of CWI if used after high-intensity exercise. FUNDING: Emma Moore is supported by a Research Training Program (Domestic) Scholarship from the Australian Commonwealth Department of Education and Training. PROTOCOL REGISTRATION: Open Science Framework: 10.17605/OSF.IO/SRB9D.


Assuntos
Desempenho Atlético , Mialgia , Temperatura Baixa , Creatina Quinase , Humanos , Imersão , Mialgia/terapia , Água
13.
Int J Sports Physiol Perform ; 17(1): 78-82, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34380111

RESUMO

PURPOSE: To prescribe training loads to improve performance, one must know how an athlete is responding to loading. The maximal rate of heart-rate increase (rHRI) during the transition from rest to exercise is linearly related to changes in endurance exercise performance and can be used to infer how athletes are responding to changes in training load. Relationships between rHRI and anaerobic exercise performance have not been evaluated. The objective of this study was to evaluate relationships between rHRI and anaerobic exercise performance. METHODS: Eighteen recreational strength and power athletes (13 male and 5 female) were tested on a cycle ergometer for rHRI, 6-second peak power output, anaerobic capacity (30-s average power), and blood lactate concentration prior to (PRE), and 1 (POST1) and 3 (POST3) hours after fatiguing high-intensity interval cycling. RESULTS: Compared with PRE, rHRI was slower at POST1 (effect size [ES] = -0.38, P = .045) but not POST3 (ES = -0.36, P = .11). PPO was not changed at POST1 (ES = -0.12, P = .19) but reduced at POST3 (ES = -0.52, P = .01). Anaerobic capacity was reduced at POST1 (ES = -1.24, P < .001) and POST3 (ES = -0.83, P < .001), and blood lactate concentration was increased at POST1 (ES = 1.73, P < .001) but not at POST3 (ES = 0.75, P = .11). rHRI was positively related to PPO (B = 0.19, P = .03) and anaerobic capacity (B = 0.14, P = .005) and inversely related to blood lactate concentration (B = -0.22, P = .04). CONCLUSIONS: rHRI is linearly related to acute changes in anaerobic exercise performance and may indicate how athletes are responding to training to guide the application of training loads.


Assuntos
Ciclismo , Exercício Físico , Aceleração , Anaerobiose , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Masculino , Consumo de Oxigênio
14.
Br J Nutr ; 127(6): 872-884, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-33971995

RESUMO

Diet is a modifiable risk factor for chronic disease and a potential modulator of telomere length (TL). The study aim was to investigate associations between diet quality and TL in Australian adults after a 12-week dietary intervention with an almond-enriched diet (AED). Participants (overweight/obese, 50-80 years) were randomised to an AED (n 62) or isoenergetic nut-free diet (NFD, n 62) for 12 weeks. Diet quality was assessed using a Dietary Guideline Index (DGI), applied to weighed food records, that consists of ten components reflecting adequacy, variety and quality of core food components and discretionary choices within the diet. TL was measured by quantitative PCR in samples of lymphocytes, neutrophils, and whole blood. There were no significant associations between DGI scores and TL at baseline. Diet quality improved with AED and decreased with NFD after 12 weeks (change from baseline AED + 9·8 %, NFD - 14·3 %; P < 0·001). TL increased in neutrophils (+9·6 bp, P = 0·009) and decreased in whole blood, to a trivial extent (-12·1 bp, P = 0·001), and was unchanged in lymphocytes. Changes did not differ between intervention groups. There were no significant relationships between changes in diet quality scores and changes in lymphocyte, neutrophil or whole blood TL. The inclusion of almonds in the diet improved diet quality scores but had no impact on TL mid-age to older Australian adults. Future studies should investigate the impact of more substantial dietary changes over longer periods of time.


Assuntos
Sobrepeso , Prunus dulcis , Adulto , Austrália , Humanos , Obesidade , Telômero
15.
Front Physiol ; 12: 771899, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34970156

RESUMO

Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) have been shown to exhibit altered ventilatory characteristics on the second of two progressive maximal cardiopulmonary exercise tests (CPET) performed on consecutive days. However, maximal exercise can exacerbate symptoms for ME/CFS patients and cause significant post-exertional malaise. Assessment of heart rate (HR) parameters known to track post-exertional fatigue may represent more effective physiological markers of the condition and could potentially negate the need for maximal exercise testing. Sixteen ME/CFS patients and 10 healthy controls underwent a sub-maximal warm-up followed by CPET on two consecutive days. Ventilation, ratings of perceived exertion, work rate (WR) and HR parameters were assessed throughout on both days. During sub-maximal warm-up, a time effect was identified for the ratio of low frequency to high frequency power of HR variability (p=0.02) during sub-maximal warm-up, and for HR at ventilatory threshold (p=0.03), with both being higher on Day Two of testing. A significant group (p<0.01) effect was identified for a lower post-exercise HR recovery (HRR) in ME/CFS patients. Receiver operator characteristic curve analysis of HRR revealed an area under the curve of 74.8% (p=0.02) on Day One of testing, with a HRR of 34.5bpm maximising sensitivity (63%) and specificity (40%) suggesting while HRR values are altered in ME/CFS patients, low sensitivity and specificity limit its potential usefulness as a biomarker of the condition.

16.
J Int Soc Sports Nutr ; 18(1): 76, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34965876

RESUMO

BACKGROUND: Increasing nitric oxide bioavailability may induce physiological effects that enhance endurance exercise performance. This review sought to evaluate the performance effects of consuming foods containing compounds that may promote nitric oxide bioavailability. METHODS: Scopus, Web of Science, Ovid Medline, EMBASE and SportDiscus were searched, with included studies assessing endurance performance following consumption of foods containing nitrate, L-arginine, L-citrulline or polyphenols. Random effects meta-analysis was conducted, with subgroup analyses performed based on food sources, sex, fitness, performance test type and supplementation protocol (e.g. duration). RESULTS: One hundred and eighteen studies were included in the meta-analysis, which encompassed 59 polyphenol studies, 56 nitrate studies and three L-citrulline studies. No effect on exercise performance following consumption of foods rich in L-citrulline was identified (SMD=-0.03, p=0.24). Trivial but significant benefits were demonstrated for consumption of nitrate and polyphenol-rich foods (SMD=0.15 and 0.17, respectively, p<0.001), including performance in time-trial, time-to-exhaustion and intermittent-type tests, and following both acute and multiple-day supplementation, but no effect of nitrate or polyphenol consumption was found in females. Among nitrate-rich foods, beneficial effects were seen for beetroot, but not red spinach or Swiss chard and rhubarb. For polyphenol-rich foods, benefits were found for grape, (nitrate-depleted) beetroot, French maritime pine, Montmorency cherry and pomegranate, while no significant effects were evident for New Zealand blackcurrant, cocoa, ginseng, green tea or raisins. Considerable heterogeneity between polyphenol studies may reflect food-specific effects or differences in study designs and subject characteristics. Well-trained males (V̇O2max ≥65 ml.kg.min-1) exhibited small, significant benefits following polyphenol, but not nitrate consumption. CONCLUSION: Foods rich in polyphenols and nitrate provide trivial benefits for endurance exercise performance, although these effects may be food dependent. Highly trained endurance athletes do not appear to benefit from consuming nitrate-rich foods but may benefit from polyphenol consumption. Further research into food sources, dosage and supplementation duration to optimise the ergogenic response to polyphenol consumption is warranted. Further studies should evaluate whether differential sex-based responses to nitrate and polyphenol consumption are attributable to physiological differences or sample size limitations. OTHER: The review protocol was registered on the Open Science Framework ( https://osf.io/u7nsj ) and no funding was provided.


Assuntos
Tolerância ao Exercício/fisiologia , Alimentos , Nitratos , Óxido Nítrico/metabolismo , Resistência Física/fisiologia , Polifenóis , Arginina/metabolismo , Arginina/farmacocinética , Citrulina/metabolismo , Citrulina/farmacocinética , Feminino , Análise de Alimentos , Humanos , Masculino , Nitratos/metabolismo , Nitratos/farmacocinética , Polifenóis/metabolismo , Polifenóis/farmacocinética , Ensaios Clínicos Controlados Aleatórios como Assunto
17.
Eur J Nutr ; 60(8): 4251-4262, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34018052

RESUMO

AIMS: Very low-carbohydrate (LC) diets are popular for type 2 diabetes (T2DM) management; however, long-term effects on psychological health remain largely unknown. This study reports the effects of a LC diet on mood and cognitive function after 2 years and explores the potential predictors of changes in psychological health. METHODS: 115 adults (57% males; age: 58.5 ± 7.1 years) with obesity and T2DM were randomized to consume an energy reduced (~ 500 to 1000 kcal/day deficit), LC diet [14% energy as carbohydrate, 28% protein, 58% fat (< 10% saturated fat)] or an isocaloric high unrefined carbohydrate, low-fat diet [HC: 53% carbohydrate, 17% protein, 30% fat (< 10% saturated fat)] for 2 years. Both diets were combined with aerobic/resistance exercise (1 h, 3 days/week). Mood/well-being [Beck Depression Inventory (BDI), Spielberger State Anxiety Inventory (SAI), Profile of Mood States (POMS)], diabetes-related quality of life [Diabetes-39 (D-39)] and distress [Problem Areas in Diabetes (PAID) Questionnaire], and cognitive function were assessed during and post-intervention. RESULTS: 61 (LC: 33, HC: 28) participants completed the study. Weight loss was 9.1% after 12 months and 6.7% after 2 years with no difference between diet groups. There were no differences between the groups for the changes in any psychological health outcome (smallest p ≥ 0.19 for all time x diet interactions). Overtime, improvements in BDI, POMS [Total Mood Disturbance (TMD); four subscales], PAID, and D-39 (three subscales) scores occurred (p ≤ 0.05, time). Stepwise regression analysis showed improvements in BDI, POMS (TMD; two subscales), D-39, SAI, and PAID scores were significantly (p < 0.05) correlated with reductions in body weight and glycated hemoglobin. CONCLUSION: In adults with obesity and T2DM, energy-restricted LC and HC diets produced comparable long-term improvements on a comprehensive range of psychological health outcomes. The findings suggest both diets can be used as a diabetes management strategy as part of a holistic lifestyle modification program without concern of negative effects on mental well-being or cognition. TRIAL REGISTRATION: ACTRN12612000369820, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=362168&isReview=true . Data described in the manuscript, code book, and analytic code will not be made available because approval has not been granted by participants.


Assuntos
Diabetes Mellitus Tipo 2 , Redução de Peso , Adulto , Idoso , Carboidratos , Dieta com Restrição de Carboidratos , Dieta com Restrição de Gorduras , Dieta Redutora , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade , Qualidade de Vida
18.
J Sport Health Sci ; 9(6): 530-541, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33308804

RESUMO

BACKGROUND: Despite the known contribution of sport to health and well-being, sport participation declines in older age. However, for some people, sport continues to play an important role in older age and may contribute to improved health and well-being in older years. Although the health-related benefits of participating in sport are commonly reported, the reasons why some older adults continue to play sport are not well understood. This systematic review aimed to (1) identify studies from the literature that evaluated the reasons why older adults (aged 55 years and older) participate in sport and (2) synthesize and discuss the reasons for their participation reported in the literature. METHODS: Searches of the electronic databases Embase, Medline, PsycInfo, PubMed, and SPORTDiscus were performed. Studies were included that evaluated reasons for sport participation in adults aged 55 years and older because this is the age at which sport participation has been reported to begin declining. The studies included in this review used qualitative, quantitative, or mixed methods designs, were peer reviewed, and were published in the English language before the search date (20 January 2019). RESULTS: A total of 1732 studies were identified. After exclusions, 30 studies were included in the review (16 qualitative, 10 quantitative, and 4 mixed methods). The review presents several features and findings from the studies, including a description and systematization of the reasons for participating in sport and the main reasons that participants gave for participating in sport (maintaining health, feeling and being part of a community, and taking advantage of opportunities to develop relationships). Other reasons included competing and attaining a feeling of achievement, taking advantage of opportunities for travel, and being part of a team. Sport was identified as contributing to the overall experience of successful ageing. There were few comparative differences for participating in sport, and there were only small differences between genders for the reasons given for participation. Generally, the quality of the studies was good; however, mixed methods studies lacked appropriate data analysis procedures. CONCLUSION: Older adults play sport for a range of health-related and social reasons that can contribute to the experience of successful ageing. Strategies to increase sport participation by older adults should focus on promoting these aspects.


Assuntos
Envelhecimento/psicologia , Esportes/psicologia , Idoso , Envelhecimento/fisiologia , Comportamento Competitivo , Estilo de Vida Saudável , Humanos , Pessoa de Meia-Idade , Fatores Sexuais , Interação Social , Esportes/fisiologia , Esportes de Equipe , Viagem
19.
Nutr Rev ; 78(12 Suppl 2): 49-52, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33259614

RESUMO

The application of science to human nutrition over the centuries has served societies well. One example is the identification of key nutrients to overcome nutritional deficiencies, which has enhanced life expectancy. Enhanced life expectancy, however, is associated with an increased prevalence of chronic disorders related to food and nutrition. Findings of studies indicating that individual responses to nutrients differ substantially between individuals make it necessary to re-examine the relationship between nutrition and human health. The emergence of new genomic-based technologies illustrates the complexity and scale of the interactions between nutrition and genetic factors. Epigenetic modifications resulting from interactions of the genetic profile, aging, and lifestyle can influence the time course of chronic disorders and contribute to human variability in response to nutritional interventions. Developing a better understanding of human variability as it applies to human nutrition will involve embracing the approaches and principles of complex science.


Assuntos
Envelhecimento , Variação Biológica da População , Alimentos , Doença Crônica , Epigênese Genética , Genômica , Humanos , Estilo de Vida
20.
Diabetes Res Clin Pract ; 170: 108501, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33058957

RESUMO

BACKGROUND: Growing evidence supports use of very low-carbohydrate (LC) diets for glycaemic control in type 2 diabetes. However, limited data on the micronutrient adequacy of LC diets exist. OBJECTIVE: This study compared the long-term effects of a very low-carbohydrate, high unsaturated/low saturated fat (LC) diet to a high-carbohydrate, low-fat (HC) diet on micronutrient biomarkers in adults with obesity and type 2 diabetes. METHODS: 115 adults with type 2 diabetes (mean[SD]; BMI:34.6[4.3]kg/m2, age:58[7]yrs, HbA1c:7.3[1.1]%, 56[12]mmol/mol) were randomized to one of two planned, nutritionally-replete, energy-matched, hypocaloric diets (500-1000 kcal/day deficit): (1) LC:14% energy carbohydrate, 28%protein, 58%fat[<10% saturated fat]) or (2) HC:53%carbohydrate, 17%protein, 30%fat [<10%saturated fat]) for 2 years. Nutritional biomarkers- folate, ß-carotene, vitamin B12, D, E, copper, zinc, selenium, calcium, magnesium, sodium, potassium, iron, ferritin, transferrin and transferrin saturation were measured in fasting blood at baseline, 24, 52 and 104 weeks. RESULTS: 61 participants completed the study with similar dropouts in each group (P = 0.40). For all biomarkers assessed, there were no differential response between groups overtime (P ≥ 0.17 time × diet interaction). Mean vitamin and mineral levels remained within normal (laboratory-specific) reference ranges without any reported cases of clinical deficiencies. CONCLUSION: In free-living individuals with type 2 diabetes, nutrition biomarkers within normal ranges at baseline did not change significantly after 2 years on a prescribed LC or HC diet. These results demonstrate the feasibility of delivering a nutritionally replete LC diet and the importance of considering nutritional factors in planning LC diets that have strong public health relevance to the dietary management of type 2 diabetes. TRIAL REGISTRATION: http://www.anzctr.org.au/, ANZCTR No. ACTRN12612000369820.


Assuntos
Carboidratos/efeitos adversos , Diabetes Mellitus Tipo 2/dietoterapia , Dieta com Restrição de Carboidratos/métodos , Dieta com Restrição de Gorduras/métodos , Avaliação Nutricional , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
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