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AIM: To determine the clinical outcomes and evaluate the perspectives of children with Type 1 diabetes (T1D) and their parents managing their child on hybrid closed-loop (HCL) therapy. METHODS: Children with T1D on HCL attending a tertiary diabetes centre between April 2019 and July 2021 were included. A retrospective analysis of glycaemic data was conducted to determine the clinical outcomes. Time spent in closed loop, time in target glucose range (TIR 3.9-10 mmol/L), hypoglycaemia and hyperglycaemia were collected at baseline, 4 weeks, 3 and 6 months post-HCL. User experience was assessed by questionnaires administered to parents of children with T1D. RESULTS: Seventy-one children, mean (SD) age of 12.2 (3.2) years were commenced on HCL. Ten (14%) discontinued HCL use, with 60% discontinuing within the first 6 months. Glycaemic outcomes were analysed in 52 children. Time spent in closed loop was 78 (21) % at 4 weeks, declined to 69 (28) % at 3 months (P = 0.037) and 63 (34) % at 6 months (P = 0.001). The mean %TIR increased from 59.8 at baseline to 67.6 at 3 months and 65.6 at 6 months with a mean adjusted difference of 7.8% points [95% CI 3.6, 11.9] and 5.5% points [95% CI 1.4, 9.5], respectively. There was a reduction in time > 10 mmol/L and time < 3.9 mmol/L from baseline to 6 months. Although families faced challenges with technology, better glucose control with reduced glycaemic fluctuations were reported. CONCLUSIONS: HCL therapy is associated with improved glycaemia; however, adequate support and education are required for best outcomes.
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Diabetes Mellitus Tipo 1 , Adolescente , Austrália , Glicemia , Automonitorização da Glicemia , Criança , Diabetes Mellitus Tipo 1/tratamento farmacológico , Humanos , Hipoglicemiantes , Insulina , Sistemas de Infusão de Insulina , Estudos RetrospectivosRESUMO
The application of dual-energy X-ray absorptiometry (DXA) in sport science settings is gaining popularity due to its ability to assess body composition. The International Society for Clinical Densitometry (ISCD) recommends application of the least significant change (LSC) to interpret meaningful and true change. This is calculated from same-day consecutive scans, thus accounting for technical error. However, this approach does not capture biological variation, which is pertinent when interpreting longitudinal measurements, and could be captured from consecutive-day scans. The aims of this study were to investigate the impact short-term biological variation has on LSC measures, and establish if there is a difference in precision based on gender in a resistance-trained population. Twenty-one resistance-trained athletes (age: 30.6 ± 8.2 yr; stature: 174.2 ± 7.2 cm; mass: 74.3 ± 11.6 kg) with at least 12 mo consistent resistance training experience, underwent 2 consecutive DXA scans on 1 d of testing, and a third scan the day before or after. ISCD-recommended techniques were used to calculate same-day and consecutive-day precision error and LSC values. There was high association between whole body (R2â¯=â¯0.98-1.00) and regional measures (R2â¯=â¯0.95-0.99) for same-day (R2â¯=â¯0.98-1.00), and consecutive-day (R2â¯=â¯0.95-0.98) measurements. The consecutive-day precision error, in comparison to same-day precision error, was significantly different (p < 0.05), and almost twice as large for fat mass (1261 g vs 660 g), and over 3 times as large for lean mass (2083 g vs 617 g), yet still remained within the ISCD minimum acceptable limits for DXA precision error. No whole body differences in precision error were observed based on gender. When tracking changes in body composition, the use of precision error and LSC values calculated from consecutive-day analysis is advocated, given this takes into account both technical error and biological variation, thus providing a more accurate indication of true and meaningful change.
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Absorciometria de Fóton/métodos , Composição Corporal , Treinamento Resistido , Esportes/fisiologia , Tecido Adiposo , Adulto , Braço , Feminino , Humanos , Perna (Membro) , Masculino , Músculo Esquelético , Reprodutibilidade dos Testes , Fatores Sexuais , Fatores de Tempo , Tronco , Adulto JovemRESUMO
INTRODUCTION: The Female Athlete Triad (Triad) is a syndrome describing three interrelated conditions: low energy availability (LEA), menstrual dysfunction, and low bone mineral density (BMD). Relative Energy Deficiency in Sport (RED-S) expands the Triad to include multiple physiologic consequences of LEA in both sexes. The purpose of this study is to determine the prevalence of factors associated with the Triad/RED-S in an elite para athlete population. METHODS: Athletes were U.S. elite para athletes training to qualify for the 2016 or the 2018 Paralympic Games. Participants completed an online questionnaire characterizing nutrition, menstrual status (in females), bone health, and awareness of the Triad/RED-S. RESULTS: The athletes were 260 elite para athletes (150 male, 110 female). While few reported prior eating disorder (3.1%), 32.4% had elevated Eating Disorder Examination Questionnaire (EDE-Q) pathologic behavior subscale scores. Most athletes (95 male, 65 female) were attempting to change their body composition or weight to improve performance. Forty-four percent of premenopausal females had oligomenorrhea/amenorrhea. Bone stress injury was reported in 9.2% of athletes; of these, 54.5% (n = 12) had low BMD. Less than 10% of athletes reported awareness of the Triad/RED-S. CONCLUSIONS: Factors associated with the Triad/RED-S are present in an elite para athlete population, regardless of sex or sport type. Awareness of the Triad/RED-S in para athletes is low. The consequences of LEA in para athlete populations are poorly understood. However, the high prevalence of factors observed suggests value in advancing screening tools and education efforts to optimize health in this population.
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Densidade Óssea , Metabolismo Energético , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Síndrome da Tríade da Mulher Atleta/fisiopatologia , Fraturas de Estresse/fisiopatologia , Distúrbios Menstruais/fisiopatologia , Esportes para Pessoas com Deficiência , Adulto , Atletas , Composição Corporal , Peso Corporal , Doenças Ósseas/fisiopatologia , Feminino , Humanos , Masculino , Prevalência , Inquéritos e Questionários , Adulto JovemRESUMO
Recent studies suggest that a substantial proportion of athletes with spinal cord injury have insufficient 25(OH) vitamin D (25(OH)D) status, which may be associated with decreased muscle strength. This study consisted of two parts: (a) to examine the effects of a 12- to 16-week vitamin D3 supplementation protocol on 25(OH)D concentration and (b) to determine whether subsequent 25(OH)D status impacts muscle performance in elite athletes with spinal cord injury. Thirty-four members (age: 33 ± 15 years, weight: 69.6 ± 28.2 kg, and height: 170.2 ± 25.4 cm) of the U.S. and Canadian Paralympic program participated in the study. 25(OH)D concentrations and performance measures (handgrip strength and 20-m wheelchair sprint) were assessed pre- and postsupplementation. Participants were assigned a vitamin D3 supplementation protocol based on initial 25(OH)D concentrations. Participants with deficient 25(OH)D status (<50 nmol/L) received 50,000 IU/week for 8 weeks, and participants with insufficient status (50-75 nmol/L) received 35,000 IU/week for 4 weeks, after which both received a maintenance dose of 15,000 IU/week. Participants with sufficient status (>75 nmol/L) received the maintenance dose of 15,000 IU/week. 25(OH)D concentrations increased significantly (p < .001; 66.3 ± 24.3 nmol/L and 111.3 ± 30.8 nmol/L pre- and postsupplementation, respectively). About 26% of athletes had sufficient 25(OH)D concentrations presupplementation, and 91% had sufficient concentrations postsupplementation. About 62% of participants improved handgrip strength postsupplementation with no change in 20-m wheelchair sprint performance. The supplementation protocol was effective for achieving sufficient vitamin D concentrations in elite athletes with spinal cord injury.
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Desempenho Atlético , Colecalciferol/administração & dosagem , Suplementos Nutricionais , Força da Mão , Traumatismos da Medula Espinal/sangue , Vitamina D/sangue , Adolescente , Adulto , Atletas , Canadá , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismos da Medula Espinal/fisiopatologia , Esportes para Pessoas com Deficiência , Estados Unidos , Deficiência de Vitamina D/terapia , Cadeiras de Rodas , Adulto JovemRESUMO
Rugby union athletes have divergent body composition based on the demands of their on-field playing position and ethnicity. With an established association between physique traits and positional requirements, body composition assessment is routinely undertaken. Surface anthropometry and dual-energy X-ray absorptiometry (DXA) are the most common assessment techniques used, often undertaken synchronously. This study aims to investigate the association between DXA and surface anthropometry when assessing longitudinal changes in fat-free mass (FFM) and fat mass (FM) in rugby union athletes. Thirty-nine elite male rugby union athletes (age: 25.7 ± 3.1 years, stature: 187.6 ± 7.7 cm, and mass: 104.1 ± 12.2 kg) underwent assessment via DXA and surface anthropometry multiple times over three consecutive international seasons. Changes in the lean mass index, an empirical measure to assess proportional variation in FFM, showed large agreement with changes in DXA FFM (r = .54, standard error of the estimate = 1.5%, p < .001); the strength of association was stronger among forwards (r = .63) compared with backs (r = .38). Changes in the sum of seven skinfolds showed very large agreement with changes in DXA FM (r = .73, standard error of the estimate = 5.8%, p < .001), with meaningful differences observed regardless of ethnicity (Whites: r = .75 and Polynesians: r = .62). The lean mass index and sum of seven skinfolds were able to predict the direction of change in FFM and FM 86% and 91% of the time, respectively, when DXA change was >1 kg. Surface anthropometry measures provide a robust indication of the direction of change in FFM and FM, although caution may need to be applied when interpreting magnitude of change, particularly with FM.
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During preseason training, rugby union (RU) athletes endeavor to enhance physical performance characteristics that are aligned with on-field success. Specific physique traits are associated with performance; therefore body composition assessment is routinely undertaken in elite environments. This study aimed to quantify preseason physique changes in elite RU athletes with unique morphology and divergent ethnicity. Twenty-two White and Polynesian professional RU athletes received dual-energy X-ray absorptiometry assessments at the beginning and conclusion of an 11-week preseason. Interactions between on-field playing position and ethnicity in body composition adaptations were explored, and the least significant change model was used to evaluate variations at the individual level. There were no combined interaction effects with the variables position and ethnicity and any body composition measure. After accounting for baseline body composition, Whites gained more lean mass during the preseason than Polynesians (2,425 ± 1,303 g vs. 1,115 ± 1,169 g; F = 5.4, p = .03). Significant main effects of time were found for whole body and all regional measures with fat mass decreasing (F = 31.1-52.0, p < .01), and lean mass increasing (F = 12.0-40.4, p < .01). Seventeen athletes (nine White and eight Polynesian) had a reduction in fat mass, and eight athletes (six White and two Polynesian) increased lean mass. This study describes significant and meaningful physique changes in elite RU athletes during a preseason period. Given the individualized approach applied to athletes in regard to nutrition and conditioning interventions, a similar approach to that used in this study is recommended to assess physique changes in this population.
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Body composition in elite rugby union athletes is routinely assessed using surface anthropometry, which can be utilized to provide estimates of absolute body composition using regression equations. This study aims to assess the ability of available skinfold equations to estimate body composition in elite rugby union athletes who have unique physique traits and divergent ethnicity. The development of sport-specific and ethnicity-sensitive equations was also pursued. Forty-three male international Australian rugby union athletes of Caucasian and Polynesian descent underwent surface anthropometry and dual-energy X-ray absorptiometry (DXA) assessment. Body fat percent (BF%) was estimated using five previously developed equations and compared to DXA measures. Novel sport and ethnicity-sensitive prediction equations were developed using forward selection multiple regression analysis. Existing skinfold equations provided unsatisfactory estimates of BF% in elite rugby union athletes, with all equations demonstrating a 95% prediction interval in excess of 5%. The equations tended to underestimate BF% at low levels of adiposity, whilst overestimating BF% at higher levels of adiposity, regardless of ethnicity. The novel equations created explained a similar amount of variance to those previously developed (Caucasians 75%, Polynesians 90%). The use of skinfold equations, including the created equations, cannot be supported to estimate absolute body composition. Until a population-specific equation is established that can be validated to precisely estimate body composition, it is advocated to use a proven method, such as DXA, when absolute measures of lean and fat mass are desired, and raw anthropometry data routinely to derive an estimate of body composition change.
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Atletas , Composição Corporal , Futebol Americano , Dobras Cutâneas , Absorciometria de Fóton , Adiposidade , Adulto , Antropometria , Austrália , Humanos , Masculino , Havaiano Nativo ou Outro Ilhéu do Pacífico , População Branca , Adulto JovemRESUMO
Tart cherry (TC) juice has many antioxidant and anti-inflammatory polyphenol compounds. TC lessens pain and accelerates strength recovery after exercise and decreases blood markers of inflammation/oxidative stress. These improvements occur in both strength and endurance exercise. TC supplementation may not be optimal during the adaptation/build stage of training. However, excessive inflammatory/oxidative stress during single-day intense training/competition or multiday tournaments may delay return to peak form. In this stage, where recovery (not adaptation) is the priority, TC may be beneficial. Timing and dosage vary widely, but most studies use 8 to 12 oz (1 oz if concentrate form) twice a day, 4- to 5-d loading phase before the event, and 2 to 3 d after to promote recovery. Therefore, for an athlete who has already peaked in training and looking to improve recovery and faster return to competition, TC may be beneficial.
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Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Sucos de Frutas e Vegetais , Mialgia/prevenção & controle , Prunus avium , Fenômenos Fisiológicos da Nutrição Esportiva , Atletas , Humanos , Inflamação/sangue , Estresse Oxidativo , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
This case study describes the nutrition plans, intakes and experiences of five ultra-marathon runners who completed the Marathon des Sables in 2011 and 2013; age 37 (28-43) y, height 184 (180-190) cm, body mass 77.5 (71-85.5) kg, marathon personal best 3:08 (2:40-3:32). MdS is a 7-day, six-stage ultra-running stage race held in the Sahara Desert (total distance of timed stages 1-5 was 233.2 km in 2011, 223.4 km in 2013). Competitors are required to carry all equipment and food (except water) for the race duration, a minimum of 8,360 kJ/day and total pack weight of 6.5-15 kg. Total food mass carried was 4.2 (3.8-4.7) kg or 0.7 (0.5-1.1) kg/day. Planned energy (13,550 (10,323-18,142) kJ/day), protein (1.3 (0.8-1.8) g/kg/day), and carbohydrate (6.2 (4.3-9.2) g/kg/day) intakes on the fully self-sufficient days were slightly below guideline recommendations, due to the need to balance nutritional needs with food mass to be carried. Energy density was 1,636 (1,475-1,814) kJ/100g. 98.5% of the planned food was consumed. Fluid consumption was ad libitum with no symptoms or medical treatment required for dehydration or hyponatremia. During-stage carbohydrate intake was 42 (20-64) g/hour. Key issues encountered by runners included difficulty consuming foods due to dry mouth, and unpalatability of sweet foods (energy gels, sports drinks) when heated in the sun. Final classification of the runners ranged from 11th to 175th of 970 finishers in 2013, and 132nd of 805 in 2011. The described pattern of intake and macronutrient quantities were positively appraised by the five runners.
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Corrida , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto , Estatura , Índice de Massa Corporal , Peso Corporal , Desidratação/prevenção & controle , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Líquidos , Ingestão de Energia , Humanos , Hiponatremia/prevenção & controle , Masculino , Avaliação Nutricional , Resistência Física , Equilíbrio HidroeletrolíticoRESUMO
This study describes the body composition traits of modern-day elite rugby union athletes according to playing position and ethnicity. Thirty-seven international Australian rugby athletes of Caucasian and Polynesian descent undertook body composition assessment using dual-energy X-ray absorptiometry and surface anthropometry. Forwards were significantly taller, heavier and had a greater total fat mass and lean mass than backs. Backs displayed a higher percentage lean mass and lower sum of seven skinfolds and percentage fat mass. While no whole body composition differences were seen between ethnicities, significant regional differences were observed. In the periphery (arm and leg) regions, Polynesians had a greater proportion of fat mass (53.1% vs. 51.3%, P = 0.052, d = 0.5) and lean mass (49.7% vs. 48.6%, P = 0.040, d = 0.9), while in the trunk region a lower proportion of fat mass (37.2% vs. 39.5%, P = 0.019, d = 0.7) and lean mass (45.6% vs. 46.8%, P = 0.020, d = 1.1). Significant differences were also seen between Caucasian and Polynesian forwards in leg lean mass (31.4 kg vs. 35.9 kg, P = 0.014, d = 2.4) and periphery lean mass (43.8 kg vs. 49.6 kg, P = 0.022, d = 2.4). Elite Polynesian rugby athletes have different distribution patterns of fat mass and lean mass compared to Caucasians, which may influence their suitability for particular positions.
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Composição Corporal , Havaiano Nativo ou Outro Ilhéu do Pacífico/etnologia , Futebol/fisiologia , População Branca/etnologia , Absorciometria de Fóton , Adiposidade , Adulto , Austrália , Índice de Massa Corporal , Humanos , Masculino , Dobras Cutâneas , Adulto JovemRESUMO
For optimal athletic performance, an athlete requires good oral health to reduce the risk of oral pain, inflammation, and infection and thereby minimize the use of analgesics and antimicrobial agents. Increased intake, frequency, and dental contact time of carbohydrate-rich foods, sports nutrition products, and acidic carbohydrate-containing sports and energy drinks may contribute to risks of dental erosion, caries, and inflammatory periodontal conditions in the athlete, especially when he or she also exhibits dehydration and poor oral hygiene habits. Examining the athlete before he or she begins participating in a sport allows the dental care provider to determine the patient's existing oral health, hygiene, and susceptibility to risk factors for erosion, caries, and inflammatory periodontal disease. This oral profile, in conjunction with the individual athlete's dietary needs, can be used to establish a treatment and preventive program, including oral health education. Good oral hygiene practices and application of topical fluoride, especially via fluoridated toothpastes and topical fluoride varnishes, must be available to the athlete. Rinsing with water or a neutral beverage after exposure to carbohydrates or acidic sports nutrition products may reduce carbohydrate contact time and bring oral pH levels back to neutral more quickly, reducing the risk of caries and erosion. Finally, the dentist should encourage the athlete to consult with an experienced sports dietitian to ensure that principles of sports nutrition are being appropriately applied for the type, frequency, and duration of exercise in consideration of the individual's oral health needs.
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Política Nutricional , Saúde Bucal/normas , Esportes/normas , Atletas , Desempenho Atlético , Assistência Odontológica , Cárie Dentária/prevenção & controle , Dieta/normas , Carboidratos da Dieta/normas , Humanos , Esportes/fisiologiaRESUMO
Quantity and timing of protein ingestion are major factors regulating myofibrillar protein synthesis (MPS). However, the effect of specific ingestion patterns on MPS throughout a 12 h period is unknown. We determined how different distributions of protein feeding during 12 h recovery after resistance exercise affects anabolic responses in skeletal muscle. Twenty-four healthy trained males were assigned to three groups (n = 8/group) and undertook a bout of resistance exercise followed by ingestion of 80 g of whey protein throughout 12 h recovery in one of the following protocols: 8 × 10 g every 1.5 h (PULSE); 4 × 20 g every 3 h (intermediate: INT); or 2 × 40 g every 6 h (BOLUS). Muscle biopsies were obtained at rest and after 1, 4, 6, 7 and 12 h post exercise. Resting and post-exercise MPS (l-[ring-(13)C6] phenylalanine), and muscle mRNA abundance and cell signalling were assessed. All ingestion protocols increased MPS above rest throughout 1-12 h recovery (88-148%, P < 0.02), but INT elicited greater MPS than PULSE and BOLUS (31-48%, P < 0.02). In general signalling showed a BOLUS>INT>PULSE hierarchy in magnitude of phosphorylation. MuRF-1 and SLC38A2 mRNA were differentially expressed with BOLUS. In conclusion, 20 g of whey protein consumed every 3 h was superior to either PULSE or BOLUS feeding patterns for stimulating MPS throughout the day. This study provides novel information on the effect of modulating the distribution of protein intake on anabolic responses in skeletal muscle and has the potential to maximize outcomes of resistance training for attaining peak muscle mass.
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Proteínas do Leite/administração & dosagem , Proteínas Musculares/biossíntese , Miofibrilas/metabolismo , Treinamento Resistido , Adulto , Aminoácidos/sangue , Ingestão de Alimentos , Humanos , Insulina/sangue , Masculino , Biossíntese de Proteínas , Fatores de Tempo , Proteínas do Soro do Leite , Adulto JovemRESUMO
Paralympic athletes may be at increased risk for exertional heat illness (EHI) due to reduced thermoregulatory ability as a consequence of their impairment. This study investigated the occurrence of heat-stress related symptoms and EHI, and the use of heat mitigation strategies in Paralympic athletes, both in relation to the Tokyo 2020 Paralympic Games and previous events. Paralympic athletes competing in Tokyo 2020 were invited to complete an online survey five weeks prior to the Paralympics and up to eight weeks after the Games. 107 athletes (30 [24-38] years, 52% female, 20 nationalities, 21 sports) completed the survey. 57% of respondents had previously experienced heat-stress related symptoms, while 9% had been medically diagnosed with EHI. In Tokyo, 21% experienced at least one heat-stress related symptom, while none reported an EHI. The most common symptom and EHI were, respectively, dizziness and dehydration. In preparation for Tokyo, 58% of respondents used a heat acclimation strategy, most commonly heat acclimatization, which was more than in preparation for previous events (45%; P = 0.007). Cooling strategies were used by 77% of athletes in Tokyo, compared to 66% during past events (P = 0.18). Cold towels and packs were used most commonly. Respondents reported no medically-diagnosed EHIs during the Tokyo 2020 Paralympic Games, despite the hot and humid conditions in the first seven days of competition. Heat acclimation and cooling strategies were used by the majority of athletes, with heat acclimation being adopted more often than for previous competitions.
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Low energy availability (LEA) is considered to be the underlying cause of a number of maladaptations in athletes, including impaired physiological function, low bone mineral density (BMD), and hormonal dysfunction. This is collectively referred to as 'Relative Energy Deficiency in Sport' (RED-S). LEA is calculated through assessment of dietary energy intake (EI), exercise energy expenditure (EEE) and fat-free mass (FFM). The incidence of LEA in Paralympic athletes is relatively unknown; however, there are legitimate concerns that Para athletes may be at even higher risk of LEA than able-bodied athletes. Unfortunately, there are numerous issues with the application of LEA assessment tools and the criterion for diagnosis within the context of a Para population. The calculation of EEE, in particular, is limited by a distinct lack of published data that cover a range of impairments and activities. In addition, for several RED-S-related factors, it is difficult to distinguish whether they are truly related to LEA or a consequence of the athlete's impairment and medical history. This narrative review outlines deficits and complexities when assessing RED-S and LEA in Para athletes, presents the information that we do have, and provides suggestions for future progress in this important area of sports nutrition.
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Paratletas , Deficiência Energética Relativa no Esporte , Atletas , Ingestão de Energia , Humanos , Fatores de RiscoRESUMO
The effects of 15 d of supplementation with L-carnitine L-tartrate (LC) on metabolic responses to graded-intensity exercise under conditions of altered substrate availability were examined. Fifteen endurance-trained male athletes undertook exercise trials after a 2-d high-carbohydrate diet (60% CHO, 25% fat) at baseline (D0), on Day 14 (D14), and after a single day of high fat intake (15% CHO, 70% fat) on Day 15 (D15) in a double-blind, placebo-controlled, pair-matched design. Treatment consisted of 3 g LC (2 g L-carnitine/d; n = 8) or placebo (P, n = 7) for 15 d. Exercise trials consisted of 80 min of continuous cycling comprising 20-min periods at each of 20%, 40%, 60%, and 80% VO2peak. There was no significant difference between whole-body rates of CHO and fat oxidation at any workload between D0 and D14 trials for either the P or LC group. Both groups displayed increased fat and reduced carbohydrate oxidation between the D14 and D15 trials (p < .05). During the D15 trial, heart rate (p < .05 for 20%, 40%, and 60% workloads) and blood glucose concentration (p < .05 for 40% and 60% workloads) were lower during exercise in the LC group than in P. These responses suggest that LC may induce subtle changes in substrate handling in metabolically active tissues when fatty-acid availability is increased, but it does not affect whole-body substrate utilization during short-duration exercise at the intensities studied.
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Metabolismo dos Carboidratos/efeitos dos fármacos , Carnitina/farmacologia , Dieta , Exercício Físico/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Administração Oral , Adulto , Ciclismo/fisiologia , Glicemia/metabolismo , Dieta Hiperlipídica , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/metabolismo , Gorduras na Dieta/administração & dosagem , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Masculino , Resistência Física/fisiologia , Tartaratos/farmacologia , Complexo Vitamínico B/farmacologia , Adulto JovemRESUMO
Athletes with cervical level spinal cord injuries (SCI) have an impaired ability to thermoregulate during exercise, leading to an increased core temperature (Tcore) due to a decrease in sweat response. Elevated Tcore may result in premature onset of fatigue and decreased athletic performance. Therefore, precooling techniques that decrease Tcore before exercise may increase the storage capacity for metabolic heat production, thereby delaying the time before reaching a critically high Tcore. The purpose of this study was to investigate the effects of pre-exercise ice slurry ingestion as a precooling method in elite athletes with SCI during a wheelchair rugby match simulation. Employing a field-based, counterbalanced-design, participants were administered 6.8 g/kg of room temperature (PLB) or ice slurry (IS) beverage during a 20-minute precooling period, before engaging in a 50 and 60 minute on-court training session on day 1 and 2, respectively. Physiological measures, including Tcore and heart rate, and perceptual measures including gastrointestinal and thermal comfort, and rating of perceived exertion, were monitored throughout precooling (minutes 10, 20) and exercise (minutes 10-60). IS had a large effect on Tcore at the midpoint of exercise on day 1 (minute 30) (ES=0.73) and 2 (minute 40) (ES=1.17). Independent samples T-tests revealed significant differences in the perception of thermal comfort between IS and PLB at the midpoint of exercise on day 1 (minute 30) (p=0.04), but not day 2 (minute 40) (p=0.05), indicating that IS may help participants to feel cooler during exercise. Although further research is warranted, pre-exercise ice slurry ingestion may provide an effective means for delaying an increase in Tcore in some athletes with SCI during a wheelchair rugby match.
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(1) Background: The purpose of this study was to examine the symptoms of low energy availability (LEA) and risk of relative energy deficiency in sport (RED-S) symptoms in para-athletes using a multi-parameter approach. (2) Methods: National level para-athletes (n = 9 males, n = 9 females) completed 7-day food and activity logs to quantify energy availability (EA), the LEA in Females Questionnaire (LEAF-Q), dual energy X-ray absorptiometry (DXA) scans to assess bone mineral density (BMD), and hormonal blood spot testing. (3) Results: Based on EA calculations, no athlete was at risk for LEA (females < 30 kcal·kg-1 FFM·day-1; and males < 25 kcal·kg-1 FFM·day-1; thresholds for able-bodied (AB) subjects). Overall, 78% of females were "at risk" for LEA using the LEAF-Q, and 67% reported birth control use, with three of these participants reporting menstrual dysfunction. BMD was clinically low in the hip (<-2 z-score) for 56% of female and 25% of male athletes (4) Conclusions: Based on calculated EA, the risk for RED-S appears to be low, but hormonal outcomes suggest that RED-S risk is high in this para-athlete population. This considerable discrepancy in various EA and RED-S assessment tools suggests the need for further investigation to determine the true prevalence of RED-S in para-athlete populations.
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Dieta/efeitos adversos , Ingestão de Energia/fisiologia , Metabolismo Energético/fisiologia , Deficiência Energética Relativa no Esporte/etiologia , Esportes para Pessoas com Deficiência/fisiologia , Absorciometria de Fóton , Adulto , Antropometria , Densidade Óssea , Dieta/estatística & dados numéricos , Registros de Dieta , Exercício Físico , Feminino , Hormônios/sangue , Humanos , Masculino , Paratletas , Fatores de Risco , Fenômenos Fisiológicos da Nutrição Esportiva , Inquéritos e QuestionáriosRESUMO
This study determined if supplementation with pantothenic acid (PA) for 16 weeks could increase skeletal muscle coenzyme A (CoASH) content and exercise performance. Trained male cyclists (n = 14) were matched into control or PA (6 g·day-1) groups. At 0, 4, 8, and 16 weeks, subjects performed an incremental time to exhaustion cycle with muscle biopsies taken prior to and following exercise. Prolonged PA supplementation did not change skeletal muscle CoASH and acetyl-CoA contents or exercise performance. Novelty: Supplementation with pantothenic acid for 16 weeks had no effect on skeletal muscle CoASH and acetyl-CoA content or exercise performance in trained male cyclists.
Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Coenzima A/metabolismo , Músculo Esquelético/enzimologia , Ácido Pantotênico/administração & dosagem , Acetilcoenzima A/metabolismo , Adulto , Suplementos Nutricionais , Humanos , Masculino , Músculo Esquelético/fisiologia , Consumo de Oxigênio , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto JovemRESUMO
PURPOSE OF REVIEW: Effective thermoregulation is paramount for optimizing athletic performance and minimizing the risk of heat illness when exercising, especially in hot conditions. Para-athletes can face unique challenges in regard to thermoregulation and hydration, especially when travel is involved. RECENT FINDINGS: For example, athletes with spinal cord injuries (SCI) have an impaired ability to thermoregulate due to a decreased sweat rate and ability to dissipate heat, thus making vigorous activity in the heat a challenge. These factors may put the athlete at risk for the following: dehydration, overheating, heat exhaustion and stroke, an inability to complete training sessions or competition, cramping, and impaired cognitive function/decision-making, which can lead to increased risk for injury. Therefore, fluid and cooling needs should be periodized and individualized according to the athlete's needs and impairment type. Strategies for cooling, and developing hydration plans for para-athletes will be reviewed.
Assuntos
Regulação da Temperatura Corporal/fisiologia , Ingestão de Líquidos , Paratletas , Água , Temperatura Alta , Humanos , TóquioRESUMO
Objective: Report measured resting energy expenditure (REE) in wheelchair rugby athletes and evaluate agreement between REE and the prediction models of Chun, Cunningham, Harris-Benedict, Mifflin, Nightingale and Gorgey, and Owen.Design: Cohort-based validation study.Setting. Paralympic team training camp.Participants: Fourteen internationally competitive athletes who play wheelchair rugby, 13 of whom had cervical spinal cord injuries (SCI).Outcome Measures: A portable metabolic analyzer was used to measure REE following an overnight fast and dual-energy X-ray absorptiometry (DXA) was used to assess lean body mass for the prediction equations.Results: REE in the current sample was 1735 ± 257â kcal × day-1 ranging from 1324 to 2068â kcal × day-1. Bland-Altman analyses revealed negative mean bias but similar limits of agreement between measured REE and scores predicted by Chun, Cunningham, Mifflin, Nightingale and Gorgey, and Owen models in elite athletes who play wheelchair rugby.Conclusion: Prediction models regressed on persons with and without SCI under-predicted REE of competitive wheelchair rugby athletes. This outcome may be explained by the higher REE/fat-free mass (FFM) ratio of current athletes compared to less active samples. Findings from the current study will help practitioners to determine nutrient intake needs on training days of varied intensity.