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Introduction: Use of nitrate as a dietary supplement has gained popularity among athletes and recreationally active individuals to enhance exercise performance. However, the prevalence and patterns of use, and knowledge of nitrate as a dietary supplement are unknown. Methods: Individuals (≥16y) completed a 42-item online questionnaire to collect (i) sociodemographic information; (ii) participation in activity and sport; (iii) nitrate supplementation use and reasons; (iv) attitudes and beliefs regarding information sources and the safety of nitrate as a dietary supplement; and (v) knowledge of dietary nitrate supplements. Results: In total, 1,404 active adults (66% female) took part in the study. Only about one in 10 respondents (11.9%) reported they had consumed dietary nitrate ("users") in the past, most commonly as beetroot juice (31.3%). Over two-thirds (69.4%) of users could not correctly identify the correct timing of intake relative to performance time to best improve exercise performance, and most users (82.3%) were unsure of the contraindications to oral consumption of dietary nitrate supplements. Only 3.9% of users experienced adverse effects after ingesting dietary nitrate supplements. Among non-users, the most common reasons respondents selected for not using dietary nitrate supplements were "I do not think I need to" (70.2%) and "I have never thought about it" (69.2%). Discussion: There is evidence to support the efficacy of dietary nitrate intake in improving exercise performance. However, findings from this study suggest dietary nitrate is under-utilized. Educational messages that target dietary nitrate consumption should be targeted toward nutritionists, coaches, and exercise physiologists to bridge the gap between knowledge-to-practice.
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OBJECTIVE: The aim of this study was to investigate the influence of morning versus evening exercise on weight loss, cardiometabolic health, and components of energy balance. METHODS: A total of 100 inactive adults with overweight or obesity were randomized to morning exercise (AMEx; 06:00-09:00), evening exercise (PMEx; 16:00-19:00), or wait-list control (CON). AMEx and PMEx were prescribed 250 min·wk-1 of self-paced aerobic exercise for 12 weeks. Anthropometry and body composition, physical activity, and dietary intake were assessed at baseline, 6 weeks, and 12 weeks. Cardiorespiratory fitness (VÌO2 peak), resting metabolic rate, and blood markers were assessed at baseline and 12 weeks. Body composition and VÌO2 peak were also measured at 3- and 6-month follow-up. RESULTS: AMEx and PMEx lost weight during the intervention (mean [SD], AMEx, -2.7 [2.5] kg, p < 0.001; PMEx, -3.1 [3.4] kg, p < 0.001). VÌO2 peak significantly increased in both intervention groups, and these changes were different from CON (AMEx, +4.7 mL·kg-1 ·min-1 , p = 0.034; PMEx, +4.2 mL·kg-1 ·min-1 , p = 0.045). There were no between-group differences for resting metabolic rate or physical activity. At 12 weeks, total energy intake was significantly reduced in both AMEx and PMEx versus CON (AMEx, -3974 kJ, p < 0.001; PMEx, -3165 kJ, p = 0.001). CONCLUSIONS: Adults with overweight and obesity experience modest weight loss in response to an exercise program, but there does not appear to be an optimal time to exercise.
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Aptidão Cardiorrespiratória , Sobrepeso , Adulto , Humanos , Sobrepeso/terapia , Exercício Físico/fisiologia , Obesidade/terapia , Redução de PesoRESUMO
BACKGROUND: Dietary nitrates may play a role in mediating several key physiological processes impacting health and/or exercise performance. However, current methods for assessing dietary nitrate (NO3 - ) consumption are inadequate. The present study aimed to examine the dietary nitrate intake in a sample of 50 healthy adults, as well as test the validity of a purposefully developed food frequency questionnaire (FFQ). METHODS: Dietary nitrate intake was estimated over a week using (i) three 24-h dietary recalls; (ii) a short-term (7-day) FFQ; and (iii) a biomarker (urinary nitrate), in conjunction with a nitrate reference database. RESULTS: Daily dietary nitrate intake estimates were 130.94 mg (average of three 24-h recalls) and 180.62 mg (FFQ). The mean urinary NO3 - excretion was 1974.79 µmol day-1 (or 917.9 µmol L-1 ). Despite the difference between the two dietary assessment methods, there was a moderate positive correlation (r = 0.736, ρ < 0.001) between the two tools. There was also a positive correlation between urinary NO3 - and 24-h recall data (r = 0.632, ρ < 0.001), as well as between urinary NO3 - and FFQ (r = 0.579, ρ < 0.001). CONCLUSIONS: The ability to accurately estimate nitrate intakes depends on having suitable reference methods to estimate the concentrations of nitrate in the food supply, coupled with valid and reliable dietary assessment tools. Based on the findings from the present study, at an individual level, dietary recalls or records may be more accurate in estimating intakes of NO3 - . However, given the lower cost and time needed for administration relative to recalls, the FFQ has merit for estimating NO3 - intakes in health interventions, dietary surveys and surveillance programs.
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Dieta , Nitratos , Adulto , Humanos , Austrália , Ingestão de Alimentos , Inquéritos e Questionários , Rememoração Mental , Reprodutibilidade dos Testes , Registros de Dieta , Inquéritos sobre Dietas , Ingestão de EnergiaRESUMO
The objective of this study was to investigate changes in sedentary and active behaviors when previously inactive adults start exercising in the morning or evening. One-hundred adults with overweight or obesity (BMI ≥ 25 kg/m2) were recruited for a 12-week intervention and randomized to one of three groups: (i) morning exercise (AMEx; 0600-0900); (ii) evening exercise (PMEx; 1600-1900); or (iii) waitlist control. AMEx and PMEx were prescribed self-paced aerobic exercise to achieve a weekly total of 250 min via a combination of supervised and unsupervised training. Sedentary and active behavior times were measured at baseline, mid- and post-intervention using the multimedia activity recall for children and adults. Time spent engaging in physical activity was significantly increased from baseline at both mid- (+ 14-22 min·day-1) and post-intervention (+ 12-19 min·day-1), for AMEx and PMEx. At 12-weeks, participants in both morning and evening exercise groups reported increased time spent Sleeping (+ 36 and + 20 min·day-1, respecitively), and reduced time spent watching TV/playing videogames (- 32 and - 25 min·day-1, respectively). In response to an exercise stimulus, previously inactive adults make encouraging modifications in how they use their time, and the patterns of change are similar with morning and evening exercise.
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Exercício Físico , Comportamento Sedentário , Adulto , Criança , Humanos , Terapia por Exercício , Obesidade , SobrepesoRESUMO
Inorganic nitrate provided by either nitrate salts or food supplements may improve cardiometabolic health. However, current methods to assess dietary nitrate, nitrite and nitrosamine consumption are inadequate. The purpose of this study was to develop a reference database to estimate the levels of nitrate, nitrite and nitrosamines in the global food supply. A systematic literature search was undertaken; of the 5,747 articles screened, 448 met the inclusion criteria. The final database included data for 1,980 food and beverages from 65 different countries. There were 5,105 unique records for nitrate, 2,707 for nitrite, and 954 for nitrosamine. For ease of use, data were sorted into 12 categories; regarding nitrate and nitrite concentrations in food and beverages, 'vegetables and herbs' were most reported in the literature (n = 3,268 and n = 1,200, respectively). For nitrosamines, 'protein foods of animal origin' were most reported (n = 398 records). This database will allow researchers and practitioners to confidently estimate dietary intake of nitrate, nitrite and nitrosamines. When paired with health data, our database can be used to investigate associations between nitrate intake and health outcomes, and/or exercise performance and could support the development of key dietary nitrate intake guidelines.
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ObjectiveTo systematically review available evidence focusing on the relationship between physical activity (PA), sedentary behavior (SB), and educational outcomes (EO), among university students. Method: Articles published in English and up to April 2019 were eligible to be included in the review if they examined associations between either PA or SB measures and EO in undergraduate university students. Results: Thirty-five articles met the eligibility criteria. The majority of papers used self-report measures of PA and SB and were rated as demonstrating poor quality (22/35). Evidence indicated no associations with EO for overall PA, MPA, VPA, and indeterminate associations for MVPA and leisure-based screen time. Conclusion: Mixed findings for PA, SB, and EO were found. Future studies should use more rigorous designs, including robust measures of relevant outcomes, to further our understanding of this area.
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Comportamento Sedentário , Estudantes , Exercício Físico , Humanos , Atividades de Lazer , UniversidadesRESUMO
BACKGROUND: To improve compliance and adherence to exercise, the concept of temporal consistency has been proposed. Before- and after-work are periods when most working adults may reasonably incorporate exercise into their schedule. However, it is unknown if there is an association between the time-of-day that exercise is performed and overall physical activity levels. METHODS: Activity was assessed over 1 week in a sample of 69 active adults (n = 41 females; mean age = 34.9 [12.3] y). At the end of the study, participants completed an interviewer-assisted questionnaire detailing their motivation to exercise and their exercise time-of-day preferences. RESULTS: Participants were classified as "temporally consistent" (n = 37) or "temporally inconsistent" (n = 32) exercisers based on their accelerometry data. The "temporally consistent" group was further analyzed to compare exercise volume between "morning-exercisers" (n = 16) and "evening-exercisers" (n = 21). "Morning-exercisers" performed a greater volume of exercise than "evening-exercisers" (419 [178] vs 330 [233] min by self-report; 368 [224] vs 325 [156] min actigraph-derived moderate to vigorous physical activity, respectively). CONCLUSIONS: Our findings suggest that active individuals use a mixture of temporal patterns to meet PA guidelines. Time-of-day of exercise should be reported in intervention studies so the relationship between exercise time-of-day, exercise behavior, and associated outcomes can be better understood.
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Exercício Físico , Comportamento Sedentário , Acelerometria , Adulto , Estudos Transversais , Feminino , Humanos , AutorrelatoRESUMO
The aim of this study was to investigate short- and long-term compensatory effects on dietary intake following high intensity interval training (HIIT) compared with usual care moderate intensity continuous training (MICT) during and following a cardiac rehabilitation program. This study investigates secondary outcomes of a clinical trial. Ninety-three participants with coronary artery disease enrolled in a 4-week cardiac rehabilitation program, were randomised to 1) 4x4-minute HIIT; or 2) 40-min of MICT (usual care). Patients were instructed to complete 3 weekly sessions (2 supervised, 1 home-based) for 4-weeks, and 3 weekly home-based sessions thereafter for another 48-weeks. Dietary intake was measured by telephone-based 24-h recall over 2 day at baseline, 4-weeks, 3-months, 6-months, and 12-months. Three-Factor Eating Questionnaire was used to measure dietary behaviour and Leeds Food Preference Questionnaire used to measure food preferences. Appetite was assessed by a visual analogue scale and appetite-regulating hormones. There was no change over the study period or differences between groups for daily energy intake at 4-weeks or 12-months. There were also no group differences for any other measures of dietary intake, fasting hunger or appetite-related hormones, dietary behaviour, or food preferences. These findings suggest that compared to moderate intensity exercise, HIIT does not result in compensatory increases of energy intake or indicators of poor diet quality. This finding appears to be the same for patients with normal weight and obesity. HIIT can therefore be included in cardiac rehabilitation programs as an adjunct or alterative to MICT, without concern for any undesirable dietary compensation.
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Reabilitação Cardíaca , Treinamento Intervalado de Alta Intensidade , Apetite , Dieta , Ingestão de Energia , HumanosRESUMO
Importance: High-intensity interval training (HIIT) is recognized as a potent stimulus for improving cardiorespiratory fitness (volume of oxygen consumption [VO2] peak) in patients with coronary artery disease (CAD). However, the feasibility, safety, and long-term effects of HIIT in this population are unclear. Objective: To compare HIIT with moderate-intensity continuous training (MICT) for feasibility, safety, adherence, and efficacy of improving VO2 peak in patients with CAD. Design, Setting, and Participants: In this single-center randomized clinical trial, participants underwent 4 weeks of supervised training in a private hospital cardiac rehabilitation program, with subsequent home-based training and follow-up over 12 months. A total of 96 participants with angiographically proven CAD aged 18 to 80 years were enrolled, and 93 participants were medically cleared for participation following a cardiopulmonary exercise test. Data were collected from May 2016 to December 2018, and data were analyzed from December 2018 to August 2019. Interventions: A 4 × 4-minute HIIT program or a 40-minute MICT program (usual care). Patients completed 3 sessions per week (2 supervised and 1 home-based session) for 4 weeks and 3 home-based sessions per week thereafter for 48 weeks. Main Outcomes and Measures: The primary outcome was change in VO2 peak during the cardiopulmonary exercise test from baseline to 4 weeks. Further testing occurred at 3, 6, and 12 months. Secondary outcomes were feasibility, safety, adherence, cardiovascular risk factors, and quality of life. Results: Of 93 randomized participants, 78 (84%) were male, the mean (SD) age was 65 (8) years, and 46 were randomized to HIIT and 47 to MICT. A total of 86 participants completed testing at 4 weeks for the primary outcome, including 43 in the HIIT group and 43 in the MICT group; 69 completed testing at 12 months for VO2 peak, including 32 in the HIIT group and 37 in the MICT group. After 4 weeks, HIIT improved VO2 peak by 10% compared with 4% in the MICT group (mean [SD] oxygen uptake: HIIT, 2.9 [3.4] mL/kg/min; MICT, 1.2 [3.4] mL/kg/min; P = .02). After 12 months, there were similar improvements from baseline between groups, with a 10% improvement in the HIIT group and a 7% improvement in the MICT group (mean [SD] oxygen uptake: HIIT, 2.9 [4.5] mL/kg/min; MICT, 1.8 [4.3] mL/kg/min; P = .30). Both groups had high feasibility scores and low rates of withdrawal due to serious adverse events (3 participants in the HIIT group and 1 participant in the MICT group). One event occurred following exercise (hypotension) in the HIIT group. Over 12 months, both home-based HIIT and MICT had low rates of adherence (HIIT, 18 of 34 [53%]; MICT, 15 of 37 [41%]; P = .35) compared with the supervised stage (HIIT, 39 of 44 [91%]; MICT, 39 of 43 [91%]; P > .99). Conclusions and Relevance: In this randomized clinical trial, a 4-week HIIT program improved VO2 peak compared with MICT in patients with CAD attending cardiac rehabilitation. However, improvements in VO2 peak at 12 months were similar for both groups. HIIT was feasible and safe, with similar adherence to MICT over 12-month follow-up. These findings support inclusion of HIIT in cardiac rehabilitation programs as an adjunct or alternative modality to moderate-intensity exercise. Trial Registration: Australian New Zealand Clinical Trials Registry Identifier: ACTRN12615001292561.
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Reabilitação Cardíaca/métodos , Doença da Artéria Coronariana/reabilitação , Treinamento Intervalado de Alta Intensidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Reabilitação Cardíaca/efeitos adversos , Estudos de Viabilidade , Feminino , Treinamento Intervalado de Alta Intensidade/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVE: This study aimed to investigate the effect of exercise intensity on visceral adipose tissue (VAT) and liver fat reduction in patients with coronary artery disease (CAD) over 3 months and the maintenance of improvements over 12 months. METHODS: Forty-two participants with CAD were randomized to three sessions/week of either 4 × 4-minute high-intensity interval training (HIIT) or 40 minutes of usual care moderate-intensity continuous training (MICT) for a 4-week supervised cardiac rehabilitation program, followed by three home-based sessions/week for 11 months. Liver fat (as intrahepatic lipid) and VAT were measured via magnetic resonance techniques. Data are mean change (95% CI). RESULTS: HIIT and MICT significantly reduced VAT over 3 months (-350 [-548 to -153] cm3 vs. -456 [-634 to -278] cm3 ; time × group effect: P = 0.421), with further improvement over 12 months (-545 [-818 to -271] cm3 vs. -521 [-784 to -258] cm3 ; time × group effect: P = 0.577) and no differences between groups. Both groups improved liver fat over 3 months, with HIIT tending to show greater reduction than MICT (-2.8% [-4.0% to -1.6%] vs. -1.4% [-2.4% to -0.4%]; time × group effect: P = 0.077). After 12 months, improvements were maintained to a similar degree. Higher exercise intensity predicted liver fat reduction (ß = -0.3 [-0.7 to 0.0]; P = 0.042). CONCLUSIONS: HIIT and MICT reduced VAT over 3 and 12 months. For liver fat, HIIT tended to provide a slightly greater reduction compared with MICT. These findings support HIIT as a beneficial adjunct or alternative to MICT for reducing visceral and liver fat in patients with CAD.
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Tecido Adiposo/metabolismo , Reabilitação Cardíaca/métodos , Doença da Artéria Coronariana/terapia , Treinamento Intervalado de Alta Intensidade/métodos , Gordura Intra-Abdominal/patologia , Fígado/metabolismo , Adiposidade/fisiologia , Idoso , Composição Corporal/fisiologia , Feminino , Humanos , Gordura Intra-Abdominal/metabolismo , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Resultado do TratamentoRESUMO
Every year, the majority of Hong Kong young adults who graduate from secondary school progress onto tertiary education. Poor eating patterns among young adults could lead to long-term health implications associated with overweight and obesity. Using the socio-ecological model as a theoretical framework, this paper reviews the current food-related policies in Hong Kong and proposes a comprehensive policy approach relevant to a variety of organizational contexts that has the potential to support positive eating patterns among young adults by enhancing the local food environment. Hong Kong has an unusual food supply in that more than 95% of food is imported, making it vulnerable to food insecurity. Education interventions commonly conducted in Hong Kong are unlikely to be helpful because young adults acquire nutrition-related knowledge when they attend secondary school. There is a need to change the food environment in Hong Kong so that young adults can easily translate their nutrition knowledge into making healthy food choices. Policy approaches might be among the most effective strategies for bringing positive changes in eating patterns because they have the potential to directly influence the food environment and context where an individual lives. A comprehensive suite of approaches that fill the policy gaps, remove barriers of healthy food consumption and create more healthy food choices is required to improve diet and health.
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Dieta Saudável , Comportamento Alimentar/psicologia , Estudantes/psicologia , Adulto , Comportamento de Escolha , Feminino , Promoção da Saúde , Hong Kong , Humanos , Masculino , Obesidade/prevenção & controle , Estudantes/estatística & dados numéricos , Universidades , Adulto JovemRESUMO
BACKGROUND: The time of day that people exercise could have an influence on the efficacy of exercise for weight loss, via differences in adherence and/or physiological adaptations. However, there is currently no evidence to support an optimal time of day for exercise to maximise efficacy. PURPOSE: To examine the feasibility and acceptability of prescribed morning and evening exercise. METHODS: Twenty inactive, overweight adults aged 18-60 years were recruited for a 12-week intervention and randomized to one of three groups using a 2:2:1 random allocation ratio: i) morning exercise (AM; nâ¯=â¯9); ii) evening exercise (PM; nâ¯=â¯7); or iii) waitlist control (CON; nâ¯=â¯4). Exercise groups were prescribed self-paced walking or running on a treadmill to achieve a weekly total of 250â¯min. Feasibility and acceptability data were collected, and physiological and behavioural outcomes associated with energy balance were measured at baseline, mid- and post-intervention. RESULTS: Attrition was low (nâ¯=â¯2 dropped out), with high measurement completion rates (>80%). The intervention groups had high adherence rates to exercise sessions (94% and 87% for the AM and PM groups, respectively). No adverse events resulting from the intervention were reported. Both intervention groups displayed improvements to their cardiometabolic risk profile; cardiorespiratory fitness improved by 5.2⯱â¯4.7, and 4.6⯱â¯4.5â¯mLâ¯kg-1.min-1 and body fat percentage reduced by 1.2⯱â¯1.4, and -0.6⯱â¯1.2% for AM and PM groups, respectively. CONCLUSION: This feasibility study provides evidence that morning and evening exercise interventions are feasible, and also provides justification for a large-scale randomized controlled trial. TRIAL REGISTRATION: This trial is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12616000457448p, 7/4/2016).
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PURPOSE: This study aimed to determine whether 1) consumption of caffeine improves endurance cycling performance in women and 2) sex differences exist in the magnitude of the ergogenic and plasma responses to caffeine supplementation. METHODS: Twenty-seven (11 women and 16 men) endurance-trained cyclists and triathletes participated in this randomized, double-blind, placebo-controlled, crossover study. Participants completed an incremental exercise test to exhaustion, two familiarization trials, and two performance trials. Ninety minutes before the performance trials, participants ingested opaque capsules containing either 3 mg·kg body mass of anhydrous caffeine or a placebo. They then completed a set amount of work (75% of peak sustainable power output) in the fastest possible time. Plasma was sampled at baseline, preexercise, and postexercise for caffeine. Strict standardization and verification of diet, hydration, training volume and intensity, and contraceptive hormone phase (for women) were implemented. RESULTS: Performance time was significantly improved after caffeine administration in women (placebo: 3863 ± 419 s, caffeine: 3757 ± 312 s; P = 0.03) and men (placebo: 3903 ± 341 s, caffeine: 3734 ± 287 s; P < 0.001). The magnitude of performance improvement was similar for women (mean = 4.3%, 95% CI = 0.4%-8.2%) and men (4.6%, 2.3%-6.8%). Plasma caffeine concentrations were similar between sexes before exercise, but significantly greater in women after exercise (P < 0.001). CONCLUSIONS: Ingestion of 3 mg·kg body mass of caffeine enhanced endurance exercise performance in women. The magnitude of the performance enhancement observed in women was similar to that of men, despite significantly greater plasma caffeine concentrations after exercise in women. These results suggest that the current recommendations for caffeine intake (i.e., 3-6 mg·kg caffeine before exercise to enhance endurance performance), which are derived almost exclusively from studies on men, may also be applicable to women.
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Ciclismo/fisiologia , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Substâncias para Melhoria do Desempenho/administração & dosagem , Resistência Física/fisiologia , Adulto , Índice de Massa Corporal , Cafeína/sangue , Estimulantes do Sistema Nervoso Central/sangue , Estudos Cross-Over , Método Duplo-Cego , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Substâncias para Melhoria do Desempenho/sangue , Fatores Sexuais , Adulto JovemRESUMO
Physical profile data from elite, sub-elite, regional, under 21s (U21), under 19s (U19) and under 17s (U17) (n = 845) players from a state netball association in Australia were analysed. Within season changes were examined for the elite and sub-elite players. Longitudinal changes were examined for the elite across four consecutive netball seasons. Elite were significantly older (24.3 ± 3.4years), taller (182.4 ± 7.2cm) and heavier (73.42 ± 6.95kg) than other playing levels (p < 0.001, ES 0.49-3.26) and had higher vertical jump (VJ) data compared to all groups (p < 0.001, ES 0.47-0.93). U17's were significantly faster than elite, sub-elite and U19 players over 5m (p < 0.05, ES 0.36-0.58) while elite were faster over 20m compared to all groups (p < 0.01, ES 0.45-0.72). Elite achieved a greater distance (1350.8m; p < 0.05, ES 0.32-0.50) in the Yo-YoIRT1 compared to the sub-elite, regional, U19 and U17. VJ height significantly increased from the 2014 (51.6 ± 4.8cm) to the 2017 season (59.6 ± 6.3cm) for the elite players (p < 0.01, ES 1.18). Yo-YoIRT1 test scores increased significantly between the pre-season and in-season phases (p < 0.05, ES 0.17).
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Composição Corporal , Aptidão Física , Esportes/fisiologia , Fatores Etários , Distribuição da Gordura Corporal , Estatura , Índice de Massa Corporal , Peso Corporal , Comportamento Competitivo/fisiologia , Humanos , Estudos Longitudinais , Resistência Física/fisiologia , Valores de Referência , Corrida/fisiologiaRESUMO
Single bouts of acute exercise do not appear to increase subsequent energy intake (EI), even when energy deficit is large. However, studies have shown a compensatory effect on EI following chronic exercise, and it remains unclear whether this is affected by exercise intensity. We investigated the chronic effect of high-intensity interval training (HIIT) and sprint interval training (SIT) on EI when compared with moderate-intensity continuous training (MICT) or no exercise (CON). Databases were searched until 13 March 2017 for studies measuring EI in response to chronic exercise (≥4 weeks of duration) of a high-intensity interval nature. Meta-analysis was conducted for between-group comparisons on EI (kilojoules) and bodyweight (kg). Results showed large heterogeneity, and therefore, metaregression analyses were conducted. There were no significant differences in EI between HIIT/SIT versus MICT (P=0.282), HIIT/SIT versus CON (P=0.398), or MICT versus CON (P=0.329). Although bodyweight was significantly reduced after HIIT/SIT versus CON but not HIIT/SIT versus MICT (in studies measuring EI), this was not clinically meaningful (<2% mean difference). In conclusion, there is no compensatory increase in EI following a period of HIIT/SIT compared to MICT or no exercise. However, this review highlights important methodological considerations for future studies.
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Ingestão de Energia , Treinamento Intervalado de Alta Intensidade , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
OBJECTIVE: To use the Reach, Effectiveness, Adoption, Implementation, and Maintenance framework to evaluate and understand key implementation and context factors of a diet and physical activity (PA) workplace intervention for nurses. METHODS: A 3-month pilot intervention was developed to promote diet and PA behavior through self-monitoring, goal setting, and social support using pedometers, a smartphone app, and a dedicated Facebook group. Measures included diet quality, daily PA, adoption, and implementation (including qualitative data). Maintenance was assessed at 6-month follow-up. RESULTS: Forty-seven nurses participated in the study. At 3 months, fruit and vegetable intake significantly increased (P = .04) whereas PA significantly decreased (P = .01). The intervention was partially adopted as planned, with low reach and efficacy. Participants reported that changing 2 behaviors at the same time was difficult, with the majority feeling it was easier to change diet than to become more physically active. CONCLUSIONS AND IMPLICATIONS: The ability to change diet and PA behaviors at the same time was challenging in nurses. Future studies examining whether similar occupational groups with high stress, fatigue, and lack of time face the same challenges would contribute to understanding these results.
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Dieta/estatística & dados numéricos , Comportamentos Relacionados com a Saúde/fisiologia , Promoção da Saúde/métodos , Enfermeiras e Enfermeiros , Local de Trabalho , Adulto , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos PilotoRESUMO
This investigation (i) examined changes in tear osmolarity in response to fluid loss that occurs with exercise in a field setting, and (ii) compared tear osmolarity with common field and laboratory hydration measures. Sixty-three participants [age 27.8 ± 8.4 years, body mass 72.15 ± 10.61 kg] completed a self-paced 10 km run outside on a predetermined course. Body mass, tear fluid, venous blood and urine samples were collected immediately before and after exercise. Significant (p < 0.001) reductions in body mass (1.71 ± 0.44%) and increases in tear osmolarity (8 ± 15 mOsm.L-1), plasma osmolality (7 ± 8 mOsm.kg-1), and urine specific gravity (0.0014 ± 0.0042 g.mL-1; p = 0.008) were observed following exercise. Pre- to post-exercise change in tear osmolarity was not significantly correlated (all p > 0.05) with plasma osmolality (rs = 0.24), urine osmolality (rs = 0.14), urine specific gravity (rs = 0.13) or relative body mass loss (r = 0.20). Tear osmolarity is responsive to exercise-induced fluid loss but does not correlate with the changes observed using other common measures of hydration status in the field setting. Practitioners shouldn't directly compare or replace other common hydration measures with tear osmolarity in the field. ABBREVIATIONS: BML: Body Mass Loss; CV: Coefficient of Variation; Posm: Plasma osmolality; SD: Standard Deviation; Tosm: Tear Osmolarity; Uosm: Urine Osmolality; USG: Urine Specific Gravity; WBGT: Wet bulb globe thermometer.
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Exercício Físico/fisiologia , Lágrimas/fisiologia , Adulto , Índice de Massa Corporal , Feminino , Humanos , Masculino , Concentração Osmolar , Plasma/fisiologia , Corrida/fisiologia , Urina/fisiologia , Equilíbrio Hidroeletrolítico/fisiologiaRESUMO
Lee, NA, Fell, JW, Pitchford, NW, Hall, AH, Leveritt, MD, and Kitic, CM. Combined carbohydrate and protein ingestion during Australian rules football matches and training sessions does not reduce fatigue or accelerate recovery throughout a weeklong junior tournament. J Strength Cond Res 32(2): 344-355, 2018-Australian rules football (ARF) is a physically demanding sport that can induce high levels of fatigue. Fatigue may be intensified during periods where multiple matches are played with limited recovery time. Combined carbohydrate and protein (CHO + PRO) intake during physical activity may provide performance and recovery benefits. The aim of this study was to investigate whether CHO + PRO ingestion during ARF matches and training sessions throughout a tournament would enhance performance or recovery in comparison with CHO-only ingestion. Australian rules football players (n = 21) competing in a 7-day national tournament participated in this randomized and double-blinded study. Beverages containing either CHO (n = 10) or CHO + PRO (n = 11) were provided during matches (day 1, day 4, and day 7) and training sessions (day 2 and day 3). Countermovement jumps (CMJs), ratings of muscle soreness, and autonomic function were assessed throughout the tournament. Gastrointestinal tract (GI) discomfort was measured after matches. Countermovement jump peak velocity increased in the CHO + PRO group (p = 0.01) but not in the CHO group. There were no differences in the other CMJ variables. In both groups, muscle soreness increased from days 0 and 1 to day 2 (p ≤ 0.05) but did not remain elevated. R-R intervals (time elapsed between successive peaks in QRS complexes) increased in both groups from day 1 to day 7 (mean difference = 59.85 ms, p < 0.01). Postmatch GI discomfort was not different (p > 0.05) between groups. When daily dietary protein is adequate (>1.8 g·kg·d), the ingestion of CHO + PRO during matches and training sessions throughout a tournament does not reduce muscle soreness nor have clear benefits for neuromuscular recovery or modulate autonomic function in junior ARF athletes, compared with that of CHO alone.
Assuntos
Desempenho Atlético/fisiologia , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Futebol Americano/fisiologia , Fadiga Muscular/fisiologia , Adolescente , Atletas , Austrália , Bebidas , Método Duplo-Cego , Exercício Físico , Gastroenteropatias/prevenção & controle , Humanos , Masculino , Mialgia/prevenção & controleRESUMO
AIM: The aim of the present study was to develop a parent-reported tool that will measure health-related quality of life (HRQoL) in children following ketogenic diet (KD) therapies for refractory epilepsy once it has been pilot tested and analysed. METHODS: Parents of children following KD therapies for epilepsy were recruited through a public hospital in Queensland, Australia, in 2012 and 2014. Qualitative semistructured interviews were conducted in 2012 with 13 parents who described changes seen in their child's HRQoL while on the KD. A quality of life tool (QoL) was developed by adapting the Quality of Life in Childhood Epilepsy tool based on results and themes analysed from the interviews. The KetoQoL was pilot tested with 18 parents recruited in 2014. Interrelationships between variables and questions were explored with exploratory factor analysis (EFA) to determine which questions had the greatest effect on QoL. RESULTS: The first iteration of the KetoQoL consisted of five main domains: physical, cognitive, social, intrapersonal and effects on the family. The domains were subdivided into 18 variables, totalling 54 items. EFA demonstrated that items from the physical and effects on the family domains had the greatest effect on QoL. CONCLUSIONS: KetoQoL is an HRQoL tool developed using a range of methods and assessed for both face and content validity. Further testing of KetoQoL is required to refine and confirm the factors. This work will enhance the evaluation of treatment effectiveness in children with epilepsy following the KD.
Assuntos
Dieta Cetogênica/psicologia , Epilepsia Resistente a Medicamentos/dietoterapia , Epilepsia Resistente a Medicamentos/psicologia , Pais , Qualidade de Vida , Inquéritos e Questionários , Adulto , Cuidadores , Criança , Comportamento Infantil , Cognição , Relações Familiares , Feminino , Humanos , Relações Interpessoais , Masculino , Projetos Piloto , Reprodutibilidade dos Testes , Convulsões/dietoterapia , Comportamento SocialRESUMO
Aging is associated with a vasoconstrictive, pro-coagulant, and pro-inflammatory profile of arteries and a decline in the bioavailability of the endothelium-derived molecule nitric oxide. Dietary nitrate elicits vasodilatory, anti-coagulant and anti-inflammatory effects in younger individuals, but little is known about whether these benefits are evident in older adults. We investigated the effects of 140 mL of nitrate-rich (HI-NI; containing 12.9 mmol nitrate) versus nitrate-depleted beetroot juice (LO-NI; containing ≤0.04 mmol nitrate) on blood pressure, blood coagulation, vascular inflammation markers, plasma nitrate and nitrite before, and 3 h and 6 h after ingestion in healthy older adults (five males, seven females, mean age: 64 years, age range: 57-71 years) in a randomized, placebo-controlled, crossover study. Plasma nitrate and nitrite increased 3 and 6 h after HI-NI ingestion (p < 0.05). Systolic, diastolic and mean arterial blood pressure decreased 3 h relative to baseline after HI-NI ingestion only (p < 0.05). The number of blood monocyte-platelet aggregates decreased 3 h after HI-NI intake (p < 0.05), indicating reduced platelet activation. The number of blood CD11b-expressing granulocytes decreased 3 h following HI-NI beetroot juice intake (p < 0.05), suggesting a shift toward an anti-adhesive granulocyte phenotype. Numbers of blood CD14++CD16⺠intermediate monocyte subtypes slightly increased 6 h after HI-NI beetroot juice ingestion (p < 0.05), but the clinical implications of this response are currently unclear. These findings provide new evidence for the acute effects of nitrate-rich beetroot juice on circulating immune cells and platelets. Further long-term research is warranted to determine if these effects reduce the risk of developing hypertension and vascular inflammation with aging.