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1.
Nutr Res Rev ; 36(2): 406-419, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35968693

RESUMO

Habitual dietary intakes and nutrition behaviours developed during childhood and adolescence pave the way for similar behaviours to manifest in adulthood. Childhood obesity rates have now reached a point where one in six children globally are classified as overweight or obese. Schools have the unique ability to reach almost all children during key developmental stages, making them an ideal setting for influencing children's nutrition behaviours. Evidence suggests the school food environment is not always conducive to healthy food choices and may be obesogenic. The aim of this narrative review is to explore factors that influence the healthy food and drink environment in and around schools in New Zealand. The review focused on evidence from New Zealand and Australia given the close resemblance in education systems and school food guidance. Using the Analysis Grid for Environments Linked to Obesity (ANGELO) framework, the school food environment was categorised into the following domains: economic, political, physical and socio-cultural factors. Findings suggest that food policies are not utilised within schools, and guidelines to improve the school food environment are not well implemented. Canteen profit models, lack of staff support and resources, and higher availability of low-cost unhealthy foods are among barriers that hinder implementation. This review highlights recommendations from existing evidence, including canteen pricing strategies, restriction of unhealthy foods and using peer modelling in a time-scarce curriculum to improve the school food environment. Key areas for improvement, opportunities to enhance policy implementation and untapped avenues to improve the food and nutrition behaviours of children are highlighted.


Assuntos
Serviços de Alimentação , Obesidade Infantil , Adolescente , Humanos , Criança , Promoção da Saúde , Nova Zelândia , Obesidade Infantil/epidemiologia , Obesidade Infantil/etiologia , Obesidade Infantil/prevenção & controle , Política Nutricional , Instituições Acadêmicas
2.
Artigo em Inglês | MEDLINE | ID: mdl-37599010

RESUMO

ISSUE ADDRESSED: Unhealthy food and drinks are widely available in New Zealand school canteens. The aim of this study was to assess primary school canteen food menus against the newly implemented Ministry of Health 'Food and Drink Guidance for Schools'. METHODS: A convenience sample of 133 primary school canteen menus was collected in 2020 as part of the baseline evaluation of the Healthy Active Learning initiative across New Zealand. A menu analysis toolkit was developed to assess menus in accordance with the Ministry of Health's 'Food and Drink Guidance for Schools' which classifies food items into three food categories: 'green', 'amber' and 'red'. RESULTS: Most menu items belonged to the less healthy amber (41.0%) and red (40%) food categories. Low decile schools had a lower percentage of green food items (8.6%) and a higher percentage of red food items (48.3%) compared to high decile schools. Sandwiches, filled rolls and wraps were the most commonly available items, followed by baked foods and foods with pastry. Over half of the in-house canteen menu items were classified as 'red' foods (55.3%). CONCLUSIONS: Most school canteens were not meeting the guidelines for healthy food and drink provision outlined by the Ministry of Health. Improving the food environment for children in socio-economically deprived areas needs to be prioritised to reduce inequities. SO WHAT?: This study highlights the unhealthy food environments in New Zealand schools and emphasises the need for more robust national policies and mandated school guidance.

3.
J Strength Cond Res ; 36(8): 2349-2359, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33065703

RESUMO

ABSTRACT: Lee, DCW, Ali, A, Sheridan, S, Chan, DKC, and Wong, SHS. Wearing compression garment enhances central hemodynamics? a systematic review and meta-analysis. J Strength Cond Res 36(8): 2349-2359, 2022-Compression garments (CG) are believed to enhance exercise performance and recovery by improving central hemodynamic responses. However, evidence is inconclusive. We performed a systematic review and meta-analysis to determine the effect of wearing CG at rest or after a physiological challenge on central hemodynamic responses, including cardiac output, stroke volume (SV), heart rate (HR), systolic blood pressure, diastolic blood pressure (DBP), and systemic vascular resistance in healthy individuals. The English language searches of the electronic databases SPORTDiscus, MEDLINE, and Web of Science were conducted from November 2018-February 2019. The studies involved were limited to the following: (a) original articles; (b) randomized controlled trials; (c) monitoring of central hemodynamic responses (either at rest or after a physiological challenge: maximal exercise or orthostatic challenge); and (d) healthy individuals. Of the 786 studies identified, 12 were included in the systematic review and meta-analysis. Meta-analysis was performed by the restricted maximum likelihood method. The results indicated that the effect size (ES) of wearing CG on improving central hemodynamic responses was large overall (Hedges' g = 0.55) and was large in SV (Hedges' g = 1.09) and HR (Hedges' g = 0.65). Subgroup analysis showed that the ESs in "post-physiological challenge" was large in overall (Hedges' g = 0.98), SV (Hedges' g = 1.78), HR (Hedges' g = 1.10), and DBP (Hedges' g = 0.75). Their ESs in "at rest" were not significant in all central hemodynamic responses, apart from a significant medium ES observed in SV (Hedges' g = 0.44). Healthy individuals who wear CG have marked improvement in central hemodynamic responses, particularly after a physiological challenge. More pronounced effects of CG are observed in increasing SV and reducing HR.


Assuntos
Exercício Físico , Hemodinâmica , Débito Cardíaco , Vestuário , Humanos , Resistência Vascular
4.
Eur J Appl Physiol ; 121(7): 2091-2100, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33835198

RESUMO

PURPOSE: To investigate sports compression garment (CG)-induced recovery hemodynamics and their potential impact on subsequent cycling performance. METHODS: In a randomized crossover design, 13 physically active men (20.9 ± 1.4 years; 65.9 ± 7.8 kg; 173.3 ± 4.8 cm; peak power output 254.2 ± 27.2 W) underwent 2 experimental trials. During each experimental trial, the subjects performed 20-min fatiguing preload cycling followed by 60-min passive recovery wearing either a sports CG (28.6 ± 9.4 mmHg) or gymnastic pants (CON). A 5-min all-out cycling performance test was subsequently conducted and power output and cadence were recorded. Cardiac output (CO) and stroke volume (SV) were measured using Doppler ultrasound (USCOM®). Heart rate (HR), blood lactate [BLa-], ratings of perceived exertion (RPE), leg muscle soreness (LMS), mean arterial pressure (MAP) and systemic vascular resistance (SVR) were monitored at 5, 15, 30, 45, 60 min during passive recovery. RESULTS: During the subsequent 5-min all-out cycling performance test, power output (215.2 ± 24.0 vs. 210.8 ± 21.5 W, CG vs. CON) and cadence (72.5 ± 3.8 vs. 71.2 ± 4.8 rpm, CG vs. CON) were higher in CG than CON (P < 0.05). SV was higher at 15, 30 and 45 min (P < 0.05), CO was higher at 5 and 45 min (P < 0.05), HR was lower at 15 and 30 min (P < 0.05) and [BLa-] was lower at 5 and 15 min (P < 0.05) during passive recovery, while LMS was lower at all time-points (P < 0.05) compared with CON. CONCLUSION: Sports CG improves subsequent cycling performance by enhancing hemodynamic responses and attenuating perceived muscle soreness during passive recovery in physically active men.


Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Meias de Compressão , Débito Cardíaco/fisiologia , Estudos Cross-Over , Frequência Cardíaca/fisiologia , Humanos , Lactatos/sangue , Masculino , Mialgia/prevenção & controle , Esforço Físico/fisiologia , Volume Sistólico/fisiologia , Ultrassonografia Doppler , Resistência Vascular , Adulto Jovem
5.
Int J Sports Med ; 41(1): 3-11, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31791089

RESUMO

This study evaluated the morphological changes of the lower limb and associated hemodynamic responses to different lower-body compression pressures (COMPs) in physically active, healthy individuals at rest. Each of the 32 participants underwent three trials with three different degrees of lower-body compression applied: "Low" (2.2±1.4 mmHg), "Medium" (12.9±3.9 mmHg), and "High" (28.8±8.3 mmHg). In each COMP, a cross-sectional area of leg muscles (CSAmuscle), subcutaneous fat (CSAfat), superficial vessels (SupV), deep arteries (DA), and deep veins (DV) at the calf, knee, and thigh levels were measured using magnetic resonance imaging (MRI). Additionally, blood pressure (BP), heart rate (HR), cardiac output (CO), stroke volume (SV), and systemic vascular resistance (SVR) were measured using Doppler ultrasound (USCOM®). With High COMP, calf CSAmuscle and SupV were smaller (p<0.01), whereas DA and DV were larger (p<0.05). Calf CSAfat, however, was similar among all COMPs. There were no major changes in CSAmuscle and CSAfat at knee and thigh levels. CO (3.2±0.9 L/min) and SV (51.9±16.4 mL) were higher (p<0.05) only with High COMP, but other hemodynamic variables showed no significant changes across different COMPs. The High COMP at the lower limb induces leg morphological changes and increases associated hemodynamic responses of physically active healthy individuals at rest.


Assuntos
Hemodinâmica/fisiologia , Extremidade Inferior/fisiologia , Meias de Compressão , Artérias/diagnóstico por imagem , Artérias/fisiologia , Pressão Sanguínea/fisiologia , Estudos Cross-Over , Feminino , Frequência Cardíaca/fisiologia , Humanos , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Volume Sistólico/fisiologia , Gordura Subcutânea/irrigação sanguínea , Gordura Subcutânea/diagnóstico por imagem , Gordura Subcutânea/fisiologia , Ultrassonografia Doppler , Resistência Vascular/fisiologia , Veias/diagnóstico por imagem , Veias/fisiologia , Adulto Jovem
6.
Pediatr Exerc Sci ; 32(4): 227-232, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32882683

RESUMO

PURPOSE: To investigate whether youth and adults can perceive differences in exertion between walking and running at speeds near the preferred transition speed (PTS) and if there are age-related differences in these perceptions. METHODS: A total of 49 youth (10-12 y, n = 21; 13-14 y, n = 10; 15-17 y, n = 18) and 13 adults (19-29 y) completed a walk-to-run transition protocol to determine PTS and peak oxygen uptake. The participants walked and ran on a treadmill at 5 speeds (PTS-0.28 m·s-1, PTS-0.14 m·s-1, PTS, PTS+0.14 m·s-1, PTS+0.28 m·s-1) and rated perceived exertion using the OMNI Perceived Exertion (OMNI-RPE) scale. Oxygen consumption was measured during the walk-to-run transition protocol to obtain the relative intensity (percentage of peak oxygen uptake) at PTS. OMNI-RPE scores at all speeds and percentage of peak oxygen uptake at PTS were compared between age groups. RESULTS: The 10- to 12-year-olds transitioned at a higher percentage of peak oxygen uptake than adults (64.54 [10.18] vs 52.22 [11.40], respectively; P = .035). The 10- to 14-year-olds generally reported higher OMNI-RPE scores than the 15- to 17-year-olds and adults (P < .050). In addition, the 10- to 14-year-olds failed to distinguish differences in OMNI-RPE between walking and running at PTS and PTS+0.14 m·s-1. CONCLUSIONS: Children aged 10-14 years are less able to distinguish whether walking or running requires less effort at speeds near the PTS compared with adults. The inability to judge which gait mode is less demanding could hinder the ability to minimize locomotive demands.


Assuntos
Fatores Etários , Consumo de Oxigênio , Esforço Físico , Corrida/fisiologia , Caminhada/fisiologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Adulto Jovem
7.
J Sports Sci ; 36(3): 340-347, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28349730

RESUMO

Carbohydrate (CHO) ingestion enhances "feel-good" responses during acute exercise but no study has examined the effect of regular ingestion of CHO on affective valence. We investigated the effect of CHO ingestion on perceptual responses and perceived work intensity of individual exercise sessions throughout a 10-week cycling ("spin") exercise intervention. We also assessed whether any changes in affect and/or perceived work intensity would influence health and fitness parameters. Twelve recreational exercisers (46 ± 9 years; nine females and three males) were randomly allocated to either CHO (7.5% CHO; 5 mL · kg-1 per exercise session; n = 6; CHO) or placebo (0% CHO, taste- and volume-matched solution; n = 6; PLA) groups. Participants exercised 2 × 45-min per week, over a 10-week intervention period. Perceptual measures of exertion (RPE), affect (feeling scale, FS) and activation (felt arousal scale, FAS) were assessed after each exercise session. The FAS ratings increased over time in CHO but decreased throughout the intervention in PLA (P = 0.03). There were no differences in heart rate (P = 0.70), RPE (P = 0.05) and FS (P = 0.84) between trials. Furthermore, no changes in health and fitness parameters were observed over time or between groups. CHO ingestion enhanced ratings of activation in recreational exercisers throughout a 10-week cycling intervention.


Assuntos
Afeto/fisiologia , Ciclismo/fisiologia , Ciclismo/psicologia , Carboidratos da Dieta/administração & dosagem , Percepção/fisiologia , Esforço Físico/fisiologia , Antropometria , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Aptidão Física/fisiologia
8.
J Exerc Sci Fit ; 15(2): 76-80, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29541136

RESUMO

Futsal, the 5-a-side version of soccer (i.e. 1 goalkeeper and 4 outfield players), was introduced in 1930 and continues to grow in popularity around the world. Competitive games comprise of two 20-min periods of high-intensity and intermittent activities requiring substantial physical, tactical, and technical efforts from the players. A greater understanding of the physical and skill requirements will aid the development of futsal and enable practitioners to undertake appropriate training regimes for the demands of the sport. The objective of this review is to examine key aspects of futsal such as match analysis, physiological demands, energy requirements, fitness measurements, and skill requirements. Futsal players experience fatigue as the game progresses due to the high-intensity nature of the game and the repeated maximal sprint efforts required. The intermittent nature of the sport necessitates the use of aerobic and anaerobic energy pathways throughout exercise. Therefore, a futsal player needs to have a great capacity of intermittent endurance, repeated sprint ability, and leg power, while technical aspects include the ability of high level shooting and passing skills, agility and coordination. Future research is warranted to help practitioners develop more specific tests into futsal performance, especially with regards skill.

9.
J Sports Sci ; 34(18): 1707-15, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26800448

RESUMO

Despite the increasing popularity of futsal, there is little information on performance characteristics of players. We aimed to determine the validity and reliability of a futsal shooting test and to evaluate and compare performance characteristics of three futsal playing levels. Twenty-four males (n = 8 elite, n = 8 semi-elite, n = 8 social) completed two trials to examine the reliability of the Massey Futsal Shooting Test (MFST) and to compare various fitness characteristics between groups. MFST time taken (P = 0.010), shot speed (P < 0.001) and points scored per shot (P < 0.001) were better for elite relative to social players. Test-retest reliability was acceptable for all groups, but it was most repeatable in elite players. Loughborough Soccer Passing Test performance was better in elite relative to social players (P = 0.004). There were no differences in countermovement-jump height between groups. Elite players ran faster over 5 m than both semi-elite (P = 0.043) and social (P = 0.002) and faster than the social players through 10 m (P = 0.028) and 20 m (P = 0.026). Distance covered in the Futsal Intermittent Endurance Test was higher in elite relative to semi-elite (P = 0.005) and social (P < 0.001) groups. The MFST is a valid and reliable protocol to assess futsal shooting-skill performance; elite players have superior shooting and passing skill and have greater sprinting and intermittent-running ability.


Assuntos
Desempenho Atlético , Teste de Esforço/normas , Movimento , Resistência Física , Corrida , Futebol , Análise e Desempenho de Tarefas , Adulto , Atletas , Humanos , Masculino , Força Muscular , Aptidão Física , Reprodutibilidade dos Testes , Esportes , Adulto Jovem
10.
J Sports Sci ; 34(4): 330-41, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26045170

RESUMO

We examined the influence of caffeine supplementation on cognitive performance and perceptual responses in female team-game players taking low-dose monophasic oral contraceptives of the same hormonal composition. Ten females (24 ± 4 years; 59.7 ± 3.5 kg body mass; 2-6 training sessions per week) took part in a randomised, double-blind, placebo-controlled crossover-design trial. A 90-min intermittent treadmill-running protocol was completed 60 min following ingestion of a capsule containing either 6 mg â€¢ kg(-1) anhydrous caffeine or artificial sweetener (placebo). Perceptual responses (ratings of perceived exertion (RPE), feeling scale (FS), felt arousal scale (FAS)), mood (profile of mood states (POMS)) and cognitive performance (Stroop test, choice reaction time (CRT)) were completed before, during and after the exercise protocol, as well as after ~12 h post exercise. Caffeine ingestion significantly enhanced the ratings of pleasure (P = 0.008) and arousal (P = 0.002) during the exercise protocol, as well as increased vigour (POMS; P = 0.007), while there was a tendency for reduced fatigue (POMS; P = 0.068). Caffeine ingestion showed a tendency to decrease RPE (P = 0.068) and improve reaction times in the Stroop (P = 0.072) and CRT (P = 0.087) tests. Caffeine supplementation showed a positive effect on perceptual parameters by increasing vigour and a tendency to decrease fatigue during intermittent running activity in female games players taking low-dose monophasic oral contraceptive steroids (OCS).


Assuntos
Desempenho Atlético/fisiologia , Cafeína/administração & dosagem , Cognição/efeitos dos fármacos , Exercício Físico/fisiologia , Percepção/efeitos dos fármacos , Esforço Físico/efeitos dos fármacos , Afeto/efeitos dos fármacos , Glicemia/metabolismo , Anticoncepcionais Orais Hormonais/administração & dosagem , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Corrida/fisiologia , Adulto Jovem
11.
J Strength Cond Res ; 30(9): 2416-23, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26808854

RESUMO

Atan, SA, Foskett, A, and Ali, A. Motion analysis of match play in New Zealand U13 to U15 age-group soccer players. J Strength Cond Res 30(9): 2416-2423, 2016-The purpose of this study was to investigate motion analysis in 85 players (U13-U15 years) from Auckland's Metropolitan League during 2 competitive soccer matches. Five-Hz global positioning system (with interpolated 10-Hz output) units were used to measure total distance (absolute and relative) and time spent in standing, walking, low-intensity running, medium-intensity running, high-intensity running, and sprinting. Speed thresholds for each match activity were determined through mean 10-m flying sprint peak speed for each age group. Under 15 years (U15, 6600 ± 1480 m) covered more absolute distance because of longer playing time than under 14 years (U14, 5385 ± 1296 m, p = 0.001) and under 13 years (U13, 4516 ± 702.6 m, p = 0.001). However, there were no differences in relative distances covered (U15, 94.5 ± 11.2 m·min, U14, 96.1 ± 11.9 m·min, U15, 97.3 ± 17.6 m·min, p = 0.685). Maximum speed attained during the match was faster for U15 (26.5 ± 1.68 km·h) than U14 (25.4 ± 1.93 km·h, p = 0.022) and U13 (23.5 ± 1.74 km·h, p = 0.001); there were no differences in average distance per sprint, with all age groups covering ∼16 m per sprint (p = 0.603). The current findings provide useful information for developing specific training programs for young soccer players and a framework for developing age-specific soccer simulation protocols.


Assuntos
Desempenho Atlético/fisiologia , Exercício Físico/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Adolescente , Criança , Teste de Esforço , Sistemas de Informação Geográfica , Frequência Cardíaca/fisiologia , Humanos , Masculino , Nova Zelândia , Estudos de Tempo e Movimento
12.
J Sports Sci ; 32(7): 601-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24117242

RESUMO

The aim of this study was to include self-paced exercise within a modified Loughborough Intermittent Shuttle Test (LIST-P) in order to quantify key performance variables not possible with prescribed workloads. Sixteen male games players performed two trials of the LIST-P, at least 7 days apart. The LIST-P incorporates 4 × 15-min blocks of "prescribed-pace" activity (participants exercise in time to audible signals) followed by 2 × 15-min blocks of "self-paced" running (no audible signals). Distances covered and mean speeds were monitored during self-paced exercise. Total distance covered (12.54 ± 0.45 km vs. 12.64 ± 0.32 km; P = 0.10) and mean speed (8.37 ± 0.31 km ∙ h(-1) vs. 8.44 ± 0.22 km ∙ h(-1); P = 0.10) was similar between trials. Other indices also showed the test to be reliable (Pearson's correlation = 0.89 and 0.90 (P < 0.01), total distance and mean speed, respectively; intraclass correlation coefficient = 0.88 and 0.88 (P < 0.01); standard error of measurement = ±0.13 km and ±0.09 km ∙ h(-1); coefficient of variation (CV) = 1.7% and 1.7%; ratio limits of agreement = 1.00 */÷1.03 and 1.01 */÷1.04). Sprint time was also similar between trials (2.60 ± 0.19 s vs. 2.64 ± 0.23 s; P = 0.29). Incorporating self-paced exercise within an established intermittent shuttle running test appears to be a sensitive means of quantifying key performance variables for multiple-sprint sports research.


Assuntos
Desempenho Atlético , Teste de Esforço/métodos , Resistência Física , Esforço Físico , Aptidão Física , Corrida , Futebol , Adulto , Fadiga , Humanos , Masculino , Reprodutibilidade dos Testes , Futebol/fisiologia , Adulto Jovem
13.
J Sports Sci ; 31(8): 907-16, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23256821

RESUMO

This study investigated the influence of dehydration during soccer-type intermittent exercise on isokinetic and isometric muscle function. Eight soccer players performed two 90-min high-intensity intermittent shuttle-running trials without (NF) or with (FL) fluid ingestion (5 ml · kg(-1) before and 2 ml · kg(-1) every 15 min). Isokinetic and isometric strength and muscular power of knee flexors and knee extensors were measured pre-exercise, at half-time and post-exercise using isokinetic dynamometry. Sprint performance was monitored throughout the simulated-soccer exercise. Isokinetic knee strength was reduced at faster (3.13 rad · s(-1); P = 0.009) but not slower (1.05 rad · s(-1); P = 0.063) contraction speeds with exercise; however, there was no difference between FL and NF. Peak isometric strength of the knee extensors (P = 0.002) but not the knee flexors (P = 0.065) was significantly reduced with exercise with no difference between FL and NF. Average muscular power was reduced over time at both 1.05 rad · s(-1) (P = 0.01) and 3.14 rad · s(-1) (P = 0.033) but was not different between FL and NF. Mean 15-m sprint time increased with duration of exercise (P = 0.005) but was not different between FL and NF. In summary, fluid ingestion during 90 min of soccer-type exercise was unable to offset the reduction in isokinetic and isometric strength and muscular power of the knee extensors and flexors.


Assuntos
Desidratação , Ingestão de Líquidos , Joelho/fisiologia , Músculo Esquelético/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Adulto , Desidratação/prevenção & controle , Humanos , Articulação do Joelho/fisiologia , Masculino , Contração Muscular , Força Muscular , Adulto Jovem
14.
Nutrients ; 15(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36839369

RESUMO

Adolescents may be particularly vulnerable to the effects of caffeine due to a lack of tolerance, their small size, changing brain physiology, and increasing independence. Concerns about adolescent caffeine consumption relate to potentially serious physiological and psychological effects following consumption. Motivations driving caffeine intake are not well understood among adolescents but are important to understand to reduce harmful behavioural patterns. This study explored caffeine consumption habits (sources, amount, frequency) of New Zealand adolescents; and factors motivating caffeine consumption and avoidance. The previously validated caffeine consumption habits questionnaire (CaffCo) was completed by 216 participants (15-18 years), with most (94.9%) consuming at least one caffeinated product daily. Chocolate, coffee, tea, and kola drinks were the most consumed sources. The median caffeine intake was 68 mg·day-1. Gender (boy) and being employed influenced the source, but not the quantity of caffeine consumed. One-fifth (21.2%) of adolescents consumed more than the recommended European Food Safety Authority (EFSA) safe level (3 mg·kg-1·day-1). Taste, energy, and temperature were the main motivators for consumption, and increased energy, excitement, restlessness, and sleep disturbances were reported effects following caffeine consumption. This study provides information on caffeinated product consumption among New Zealand adolescents, some of whom consumed caffeine above the EFSA safe level. Public health initiatives directed at adolescents may be important to reduce potential caffeine-related harm.


Assuntos
Cafeína , Bebidas Energéticas , Masculino , Adolescente , Humanos , Motivação , Café , Estudantes/psicologia , Instituições Acadêmicas , Bebidas Energéticas/análise
15.
Nutrients ; 15(6)2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36986096

RESUMO

Carbohydrate (CHO) supplements such as bars, gels, drinks and powders have become ubiquitous as effective evidence-based CHO sources that improve endurance exercise performance. However, athletes are increasingly turning to more cost-effective 'food-first' approaches for CHO ingestion to improve exercise performance. Mixed CHO foods including cooked lentils, oats, honey, raisins, rice, and potatoes are all effective pre-exercise CHO food sources. Caution is advised when selecting some of these foods as a primary CHO source, as some athletes may be prone to gastrointestinal discomfort-especially regarding those foods where the quantities required for recommended CHO intake may be voluminous (e.g., potatoes). Palatability may be another barrier to the ingestion of some of these CHO-rich foods. Although most of these CHO-rich foods appear effective for exercise performance or recovery when consumed pre- and post-exercise, not all are viable to ingest during exercise due to difficulties in the quantities required, transport, and/or gastrointestinal discomfort. Raisins, bananas and honey may be particularly useful CHO foods for consumption during exercise, as they are easily transportable. Athletes should trial CHO food sources before, during and/or following training before implementation during competition.


Assuntos
Carboidratos da Dieta , Resistência Física , Humanos , Exercício Físico , Hexoses , Atletas
16.
J Hum Kinet ; 83: 99-107, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36157944

RESUMO

Beta-alanine (BA) is a supplement that has received attention for its buffering potential among athletes. The aim of this study was to investigate the effects of BA supplementation on exercise performance and exercise-induced cell damage in female basketball players. Twenty-two female basketball players participated in a randomized, double-blind study. They ingested 6.4 g·day-1 of BA or an isocaloric placebo (dextrose) over 4 weeks. Exercise performance including aerobic (Bruce test), anaerobic (Wingate test), intermittent (Yo-Yo test) and basketball performance (countermovement jump and free throw shots) was measured before and following the intervention. Exercise measures were performed at the lab and free throw shots were undertaken on a wooden indoor basketball court. Blood samples were also collected before and after the exhaustive exercise to assess lactate concentration, creatine kinase (CK), lactate dehydrogenase (LDH) and malondialdehyde (MDA) activity. The exhaustive exercise test induced an increase in lactate concentration and MDA, CK and LDH activity (all p < 0.05). BA supplementation significantly reduced the lactate response to exhaustive exercise (p = 0.001); however, it had no significant effect on exercise-induced MDA, CK and LDH activity (all p > 0.05). Furthermore, exercise performance measures improved from pre- to post-test regardless of supplement/placebo ingestion (all p < 0.05). BA consumption over 4 weeks significantly reduced lactate accumulation following exhaustive exercise, but had no ergogenic effect in female basketball players. Usual dosing of BA does not seem to exhibit protective effect against oxidative damage.

17.
Nutrients ; 14(21)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36364948

RESUMO

Physiological and biological markers in different body fluids are used to measure the body's physiological or pathological status. In the field of sports and exercise medicine, the use of these markers has recently become more popular for monitoring an athlete's training response and assessing the immediate or long-term effects of exercise. Although the effect of exercise on different physiological markers using various body fluids is well substantiated, no article has undertaken a review across multiple body fluids such as blood, saliva, urine and sweat. This narrative review aims to assess various physiological markers in blood, urine and saliva, at rest and after exercise and examines physiological marker levels obtained across similar studies, with a focus on the population and study methodology used. Literature searches were conducted using PRISMA guidelines for keywords such as exercise, physical activity, serum, sweat, urine, and biomarkers, resulting in an analysis of 15 studies for this review paper. When comparing the effects of exercise on physiological markers across different body fluids (blood, urine, and saliva), the changes detected were generally in the same direction. However, the extent of the change varied, potentially as a result of the type and duration of exercise, the sample population and subject numbers, fitness levels, and/or dietary intake. In addition, none of the studies used solely female participants; instead, including males only or both male and female subjects together. The results of some physiological markers are sex-dependent. Therefore, to better understand how the levels of these biomarkers change in relation to exercise and performance, the sex of the participants should also be taken into consideration.


Assuntos
Líquidos Corporais , Esportes , Humanos , Masculino , Feminino , Exercício Físico/fisiologia , Esportes/fisiologia , Suor/química , Biomarcadores
18.
Nutrients ; 14(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36558446

RESUMO

Gymnemic-acids (GA) block lingual sweet taste receptors, thereby reducing pleasantness and intake of sweet food. Objective: To examine whether a 14-day gymnema-based intervention can reduce sweet foods and discretionary sugar intake in free-living adults. Healthy adults (n = 58) were randomly allocated to either the intervention group (INT) or control group (CON). The intervention comprised of consuming 4 mg of Gymnema sylvestre containing 75% gymnema acids, a fibre and vitamin supplement, and an associated healthy-eating guide for 14 days; participants in the CON group followed the same protocol, replacing the GA with a placebo mint. Amount of chocolate bars eaten and sensory testing were conducted before and after the 14-day intervention (post-GA or placebo dosing on days zero and 15, respectively). Food frequency questionnaires were conducted on days zero, 15 and after a 28-day maintenance period to examine any changes in intake of sweet foods. A range of statistical procedures were used to analyse the data including Chi square, t-test and two-way analysis of variance. Post dosing, INT consumed fewer chocolates (2.65 ± 0.21 bars) at day zero than CON (3.15 ± 0.24 bars; p = 0.02); there were no differences between groups at day 15 (INT = 2.77 ± 0.22 bars; CON = 2.78 ± 0.22 bars; p = 0.81). At both visits, a small substantive effect (r < 0.3) was observed in the change in pleasantness and desire ratings, with INT showing a slight increase while CON showed a small decrease over the 14-day period. No differences were found in the intake of 9 food categories between groups at any timepoint. There were no differences in consumption of low sugar healthy foods between visits, or by group. The 14-day behavioural intervention reduced pleasantness and intake of chocolate in a laboratory setting. There was no habituation to the mint over the 14-day period. This study is the first to investigate the effect of longer-term gymnema acid consumption on sweet food consumption outside of a laboratory setting; further research is needed to assess how long the effect of the 14-day intervention persists.


Assuntos
Gymnema sylvestre , Gymnema , Humanos , Adulto , Açúcares , Fissura , Preferências Alimentares , Paladar
19.
J Strength Cond Res ; 25(5): 1385-92, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21293307

RESUMO

The aim of this study was to examine the effects of wearing different grades of graduated compression stockings (GCS) on 10-km running performance. After an initial familiarization run, 9 male and 3 female competitive runners (VO2max 68.7 ± 5.8 ml·kg⁻¹·min⁻¹) completed 4 10-km time trials on an outdoor 400-m track wearing either control (0 mm Hg; Con), low (12-15 mm Hg; Low), medium (18-21 mm Hg; Med), or high (23-32 mm Hg; Hi) GCS in a randomized counterbalanced order. Leg power was assessed pre and postrun via countermovement jump using a jump mat. Blood-lactate concentration was assessed pre and postrun, whereas heart rate was monitored continuously during exercise. Perceptual scales were used to assess the comfort, tightness, and any pain associated with wearing GCS. There were no significant differences in performance time between trials (p = 0.99). The change in pre to postexercise jump performance was lower in Low and Med than in Con (p < 0.05). Mean heart rate (p = 0.99) and blood lactate (p = 1.00) were not different between trials. Participants rated Con and Low as more comfortable than Med and Hi (p < 0.01), Med and Hi were rated as tighter than Low (p < 0.01), all GCS were rated as tighter than Con (p < 0.01), and Hi was associated with the most pain (p < 0.01). In conclusion, GCS worn by competitive runners during 10-km time trials did not affect performance time; however Low and Med GCS resulted in greater maintenance of leg power after endurance exercise. Athletes rated low-grade GCS as most comfortable garments to wear during exercise.


Assuntos
Desempenho Atlético/fisiologia , Força Muscular/fisiologia , Resistência Física/fisiologia , Corrida/fisiologia , Meias de Compressão/estatística & dados numéricos , Adulto , Análise de Variância , Atletas/estatística & dados numéricos , Índice de Massa Corporal , Intervalos de Confiança , Método Duplo-Cego , Feminino , Frequência Cardíaca/fisiologia , Humanos , Extremidade Inferior/fisiologia , Masculino , Consumo de Oxigênio/fisiologia , Valores de Referência
20.
Metabolites ; 11(6)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070362

RESUMO

Metabolic syndrome (MetS) is a group of metabolic abnormalities, which together lead to increased risk of coronary heart disease (CHD) and type 2 diabetes mellitus (T2DM), as well as reduced quality of life. Dietary nitrate, betalains and anthocyanins may improve risk factors for MetS and reduce the risk of development of CHD and T2DM. Beetroot is a rich source of dietary nitrate, and anthocyanins are present in high concentrations in blackcurrants. This narrative review considers the efficacy of beetroot and blackcurrant compounds as potential agents to improve MetS risk factors, which could lead to decreased risk of CHD and T2DM. Further research is needed to establish the mechanisms through which these outcomes may occur, and chronic supplementation studies in humans may corroborate promising findings from animal models and acute human trials.

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