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1.
J Bodyw Mov Ther ; 24(4): 484-489, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33218551

RESUMO

BACKGROUND: Cancer-related fatigue (CRF) is a common symptom during and after cancer treatment that negatively affects the patient's quality of life. Exercise is one of the most effective non-pharmacological treatments for CRF. Multimodal exercise therapy programs that include hypopressive exercises, relaxation and myofascial release may be beneficial for CRF. The aim of this pilot study was to evaluate the feasibility and efficacy of a multimodal program on CRF and lower limb functional strength in postmenopausal women diagnosed with cancer. METHODS: 7 postmenopausal women (age = 55.28 years; BMI = 26.05 kg/m2) who had a cancer diagnosis participated in a supervised and progressive 55-min class once per week for 12-weeks. CRF was measured using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Cancer Related Fatigue 12 and lower limb strength was assessed with the sit and stand test. RESULTS: No adverse events were reported during the training period and all participants completed the exercise protocol. There was a significant increase (p = 0.01) in lower limb functional strength (pre: 19.60 (SD = 2.19) vs post: 24.60(SD = 2.19)) with an effect size of d = 2.28 and a decrease in CRF (p = 0.245) (pre: 29.36 ± 24.42; post: 17.85 ± 14.23) with a trivial effect size (d < 0.5). CONCLUSIONS: These preliminary findings indicate that a supervised once per week multimodal program that includes hypopressive exercises for postmenopausal cancer survivors increased lower limb functional strength without exacerbating their CRF. These findings support further randomized trials of hypopressive training programs on patients with cancer.


Assuntos
Sobreviventes de Câncer , Neoplasias , Terapia por Exercício , Fadiga/terapia , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Pós-Menopausa , Qualidade de Vida
2.
Phytother Res ; 32(8): 1593-1607, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29672965

RESUMO

The purpose of this study was to examine acute hematological and mood perception responses to supplementation with p-synephrine alone and in combination with caffeine during quiet sitting. Sixteen subjects visited the laboratory on 6 occasions and were given (in randomized double-blind manner) 103-mg p-synephrine (S), 233-mg caffeine + 104-mg p-synephrine, 240-mg caffeine, 337-mg caffeine + 46-mg p-synephrine, 325-mg caffeine, or a placebo (PL). The subjects sat quietly for 3 hr while completing mood state questionnaires every 30 min. Venous blood samples were collected at baseline (pre) and 3 hr (post) to determine immune, lipid, and chemistry panels. Compared with PL, no significant supplement differences were observed during the S trial with the exception of differential time effects seen in hematocrit (decrease in PL, no change in S), triglycerides and very low-density lipoproteins (no changes in PL, significant decreases in S), and iron (no change in PL, significant elevation in S). Supplements containing caffeine showed increased feelings of attention, excitement, energy, and vigor. These data indicate that consumption of 103-mg p-synephrine does not negatively impact acute blood parameters, does not augment the effects of caffeine, or produce stimulant-like perceptual mood effects.


Assuntos
Afeto/efeitos dos fármacos , Análise Química do Sangue , Cafeína/farmacologia , Suplementos Nutricionais , Sinefrina/farmacologia , Método Duplo-Cego , Feminino , Hematócrito , Humanos , Ferro/sangue , Lipoproteínas VLDL/sangue , Masculino , Extratos Vegetais/farmacologia , Triglicerídeos/sangue , Adulto Jovem
3.
Phytother Res ; 32(1): 94-102, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29047215

RESUMO

The purpose was to examine cardiovascular responses to supplementation with p-synephrine alone and in combination with caffeine during quiet sitting. Sixteen subjects were given (in double-blind manner) either 103 mg of p-synephrine (S), 233 mg of caffeine +104 mg of p-synephrine (LC + S), 240 mg of caffeine (LC), 337 mg of caffeine +46 mg of p-synephrine (HC + S), 325 mg of caffeine (HC), or a placebo. The subjects sat quietly for 3 hr while heart rate (HR) and blood pressure were measured. Only HC + S and HC significantly increased mean systolic blood pressure (SBP) during the second hour and tended to increase mean SBP during the third hour. Mean diastolic blood pressure in S was significantly lower than the other trials during the first and second hours, and mean arterial pressure was significantly lower in S compared to the LC, LC + S, HC, and HC + S trials. No differences were observed in HR. Consumption of p-synephrine may acutely reduce diastolic blood pressure and mean arterial pressure and not affect SBP or HR during quiet sitting. The addition of p-synephrine to caffeine did not augment SBP or HR indicating that consumption of up to 104 mg of p-synephrine does not induce cardiovascular stress during quiet sitting.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Cafeína/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Sinefrina/uso terapêutico , Doença Aguda , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Extratos Vegetais/farmacologia , Sujeitos da Pesquisa , Sinefrina/farmacologia , Adulto Jovem
4.
J Am Coll Nutr ; 35(8): 657-669, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27484437

RESUMO

OBJECTIVE: The purpose of this study was to examine the metabolic, lipolytic, and cardiovascular responses to supplementation with p-synephrine alone and in combination with caffeine during resistance exercise (RE). METHODS: Twelve healthy men performed a control RE protocol (6 × 10 repetitions of squats) and were randomly assigned (using a double-blind crossover design with random protocol sequencing) to a supplement sequence: p-synephrine (S; 100 mg), p-synephrine + caffeine (SCF; 100 mg of p-synephrine plus 100 mg of caffeine), or a placebo (P). Subjects reported to the lab at a standard time, consumed a supplement, sat quietly for 45 minutes, performed the RE protocol, and sat quietly for 30 minutes. Blood samples were collected at rest (T1), after sitting quietly for 45 minutes (T2), immediately following RE (T3), and 15 minutes (T4) and 30 minutes (T5) postexercise. Oxygen consumption (VO2) and heart rate (HR) data were collected throughout. RESULTS: Serum glycerol was significantly elevated at T2 only in S and SCF and T3 to T5 in all treatments. Nonesterified fatty acid (NEFA) concentrations did not differ between treatments. Plasma glucose was significantly elevated compared to T1 with highest area under the curve values seen in SCF. Mean VO2 and energy expenditure (EE) were significantly higher in S and SCF through 30 minutes postexercise. Fat oxidation rates favored S and SCF between 25 and 30 minutes postexercise. Mean HR during RE was significantly highest in SCF. CONCLUSIONS: Supplementation with S and SCF increases lipolysis primarily at rest and increases VO2, EE, and fat oxidation rates 30 minutes following RE. No HR changes were observed unless caffeine was added.


Assuntos
Cafeína/administração & dosagem , Sistema Cardiovascular/efeitos dos fármacos , Exercício Físico/fisiologia , Treinamento Resistido , Sinefrina/administração & dosagem , Adulto , Glicemia/análise , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Metabolismo Energético/efeitos dos fármacos , Ácidos Graxos não Esterificados/sangue , Glicerol/sangue , Frequência Cardíaca/efeitos dos fármacos , Humanos , Lipólise/efeitos dos fármacos , Masculino , Metabolismo/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos
5.
J Strength Cond Res ; 30(6): 1491-509, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26933920

RESUMO

There has recently been a growing interest in long-term athletic development for youth. Because of their unique physical, psychological, and social differences, children and adolescents should engage in appropriately prescribed exercise programs that promote physical development to prevent injury and enhance fitness behaviors that can be retained later in life. Irrespective of whether a child is involved in organized sport or engages in recreational physical activity, there remains a need to adopt a structured, logical, and evidence-based approach to the long-term development of athleticism. This is of particular importance considering the alarmingly high number of youth who fail to meet global physical activity recommendations and consequently present with negative health profiles. However, appropriate exercise prescription is also crucial for those young athletes who are physically underprepared and at risk of overuse injury because of high volumes of competition and an absence of preparatory conditioning. Whether the child accumulates insufficient or excessive amounts of exercise, or falls somewhere between these opposing ends of the spectrum, it is generally accepted that the young bodies of modern day youth are often ill-prepared to tolerate the rigors of sports or physical activity. All youth should engage in regular physical activity and thus should be viewed as "athletes" and afforded the opportunity to enhance athleticism in an individualized, holistic, and child-centered manner. Because of emerging interest in long-term athletic development, an authorship team was tasked on behalf of the National Strength and Conditioning Association (NSCA) to critically synthesize existing literature and current practices within the field and to compose a relevant position statement. This document was subsequently reviewed and formally ratified by the NSCA Board of Directors. A list of 10 pillars of successful long-term athletic development are presented, which summarize the key recommendations detailed within the position statement. With these pillars in place, it is believed that the NSCA can (a) help foster a more unified and holistic approach to long-term athletic development, (b) promote the benefits of a lifetime of healthy physical activity, and


Assuntos
Atletas , Exercício Físico/fisiologia , Esportes/fisiologia , Adolescente , Desenvolvimento do Adolescente , Criança , Transtornos Traumáticos Cumulativos/prevenção & controle , Feminino , Humanos , Masculino
6.
J Int Soc Sports Nutr ; 12: 35, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26388707

RESUMO

BACKGROUND: Little is known concerning the potential ergogenic effects of p-synephrine supplementation. Therefore, the purpose of the present study was to examine the effects of supplementation with p-synephrine alone and in combination with caffeine on free-weight resistance exercise performance. METHODS: Twelve healthy, college-aged men performed a control (CT) resistance exercise protocol consisting of 6 sets of squats for up to 10 repetitions per set using 80% of their one repetition-maximum (1RM) with 2 min of rest in between sets. Each subject was randomly assigned (in double-blind, balanced manner) to a treatment sequence consisting of use of 3 supplements: p-synephrine (S; 100 mg), p-synephrine + caffeine (SCF; 100 mg of p-synephrine plus 100 mg of caffeine), or a placebo (P). For each supplement treatment (separated by 1 week), subjects consumed the supplement for 3 days prior to each protocol and the morning of each protocol, and subsequently did not consume any supplements for 3 days following (i.e. wash-out period). On each protocol day, subjects reported to the lab at a standard time, consumed a supplement, sat quietly for 45 min, performed the resistance exercise protocol, and sat quietly for 30 min post exercise. Performance (repetition number, force, velocity and power), blood lactate, and ratings of perceived exertion (RPE) data were collected during each protocol. RESULTS: Supplements SCF and S produced a significantly (P < 0.05) greater number of repetitions performed than CT (by 11.0 ± 8.0%) and P (by 6.0 ± 7.0%) and a 10.6 ± 12.0% greater increase in volume load per protocol than CT and P. Most of the differences were seen during the last 3 sets. Mean power and velocity for all 6 sets were significantly higher in SCF compared to CT and P by ~6.2 ± 8.0%. No supplement effects were observed in RPE or blood lactate, and no adverse side effects were observed or reported. CONCLUSIONS: S and SCF augmented resistance exercise performance (total repetitions, volume load) without increasing blood lactate or RPE. The addition of caffeine in SCF increased mean power and velocity of squat performance. These results indicate supplementation with S and SCF can enhance local muscle endurance during resistance exercise.


Assuntos
Cafeína/farmacologia , Contração Isométrica/efeitos dos fármacos , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Treinamento Resistido , Sinefrina/farmacologia , Desempenho Atlético , Cafeína/administração & dosagem , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Contração Isométrica/fisiologia , Masculino , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Consumo de Oxigênio , Resistência Física/fisiologia , Sinefrina/administração & dosagem , Adulto Jovem
7.
Curr Sports Med Rep ; 12(4): 248-55, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23851413

RESUMO

Despite the widely recognized benefits of daily play, recreation, sports, and physical education on the physical and psychosocial well-being of children and adolescents, many contemporary children and adolescents worldwide do not meet the recommendations for daily physical activity (PA). The decline in PA seems to start early in life, which leads to conditions characterized by reduced levels of PA in the pediatric population that are inconsistent with current public health recommendations. Unlike many other diseases and disorders in pediatrics, physical inactivity in youth is unique in that it currently lacks a clinical gold standard for diagnosis. This makes the diagnosis and treatment medically challenging, though no less important, as the resultant ramifications of a missed diagnosis are of significant detriment. Exercise-deficient children need to be identified early in life and treated with developmentally appropriate exercise programs designed to target movement deficiencies and physical weaknesses in a supportive environment. Without such interventions early in life, children are more likely to become resistant to our interventions later in life and consequently experience adverse health consequences. Integrative approaches that link health care professionals, pediatric exercise specialists, school administrators, community leaders, and policy makers may provide the best opportunity to promote daily PA, reinforce desirable behaviors, and educate parents about the exercise-health link.


Assuntos
Exercício Físico , Comportamentos Relacionados com a Saúde , Promoção da Saúde/organização & administração , Educação Física e Treinamento/organização & administração , Aptidão Física , Comportamento Sedentário , Adolescente , Criança , Comportamento Infantil , Pré-Escolar , Feminino , Humanos , Masculino , Estados Unidos
8.
Phys Sportsmed ; 39(1): 74-84, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21378489

RESUMO

As more children and adolescents participate in sports and conditioning activities (sometimes without consideration for cumulative workload), it is important to establish age-appropriate training guidelines that may reduce the risk of sports-related injury and enhance athletic performance. The purpose of this article is to review the scientific evidence on youth strength and conditioning and to provide age-appropriate recommendations for integrating different strength and conditioning activities into a well-designed program that is safe, effective, and enjoyable. Integrative training is defined as a program or plan that incorporates general and specific strength and conditioning activities that enhance both health- and skill-related components of physical fitness. The cornerstone of integrative training is age-appropriate education and instruction by qualified professionals who understand the physical and psychosocial uniqueness of children and adolescents.


Assuntos
Traumatismos em Atletas/prevenção & controle , Desempenho Atlético/fisiologia , Força Muscular/fisiologia , Educação Física e Treinamento/métodos , Aptidão Física , Adolescente , Criança , Humanos , Educação Física e Treinamento/normas
9.
J Int Soc Sports Nutr ; 7: 8, 2010 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-20181080

RESUMO

BACKGROUND: The effect of acute L-alanyl-L-glutamine (AG; Sustamine) ingestion on performance changes and markers of fluid regulation, immune, inflammatory, oxidative stress, and recovery was examined in response to exhaustive endurance exercise, during and in the absence of dehydration. METHODS: Ten physically active males (20.8 +/- 0.6 y; 176.8 +/- 7.2 cm; 77.4 +/- 10.5 kg; 12.3 +/- 4.6% body fat) volunteered to participate in this study. During the first visit (T1) subjects reported to the laboratory in a euhydrated state to provide a baseline (BL) blood draw and perform a maximal exercise test. In the four subsequent randomly ordered trials, subjects dehydrated to -2.5% of their baseline body mass. For T2, subjects achieved their goal weight and were not rehydrated. During T3 - T5, subjects reached their goal weight and then rehydrated to 1.5% of their baseline body mass by drinking either water (T3) or two different doses (T4 and T5) of the AG supplement (0.05 g.kg-1 and 0.2 g.kg-1, respectively). Subjects then exercised at a workload that elicited 75% of their VO2 max on a cycle ergometer. During T2 - T5 blood draws occurred once goal body mass was achieved (DHY), immediately prior to the exercise stress (RHY), and immediately following the exercise protocol (IP). Resting 24 hour (24P) blood samples were also obtained. Blood samples were analyzed for glutamine, potassium, sodium, aldosterone, arginine vasopressin (AVP), C-reactive protein (CRP), interleukin-6 (IL-6), malondialdehyde (MDA), testosterone, cortisol, ACTH, growth hormone and creatine kinase. Statistical evaluation of performance, hormonal and biochemical changes was accomplished using a repeated measures analysis of variance. RESULTS: Glutamine concentrations for T5 were significantly higher at RHY and IP than T2 - T4. When examining performance changes (difference between T2 - T5 and T1), significantly greater times to exhaustion occurred during T4 (130.2 +/- 340.2 sec) and T5 (157.4 +/- 263.1 sec) compared to T2 (455.6 +/- 245.0 sec). Plasma sodium concentrations were greater (p < 0.05) at RHY and IP for T2 than all other trials. Aldosterone concentrations at RHY and IP were significantly lower than that at BL and DHY. AVP was significantly elevated at DHY, RHY and IP compared to BL measures. No significant differences were observed between trials in CRP, IL-6, MDA, or in any of the other hormonal or biochemical measures. CONCLUSION: Results demonstrate that AG supplementation provided a significant ergogenic benefit by increasing time to exhaustion during a mild hydration stress. This ergogenic effect was likely mediated by an enhanced fluid and electrolyte uptake.

10.
Amino Acids ; 38(3): 771-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19347247

RESUMO

The effect of 42 g of protein ingested pre- and post-exercise on recovery from an acute resistance exercise session was examined in 15 male strength/power athletes who were randomly divided into a supplement (SUP) or placebo (PL) group. Subjects reported to the Human Performance Laboratory (HPL) on four separate occasions (T1-T4). Maximal strength [one repetition-maximum (1-RM)] testing was performed during T1. During T2 subjects performed four sets of ten repetitions at 80% of their 1-RM in the squat, dead lift and barbell lunge exercises with 90 s of rest between each set. Blood draws occurred at baseline (BL), immediate and 15 min post-exercise to determine testosterone, cortisol and creatine kinase (CK) concentrations. Subjects reported back to the HPL 24 (T3) and 48 h (T4) post-exercise for a BL blood draw and to perform four sets of ten repetitions with 80% of 1-RM for the squat exercise only. No differences in the number of repetitions performed in the squat exercise were seen between the groups at T2. Relative to T2, PL performed significantly (P < 0.05) fewer repetitions than SUP at T3 and T4 (-9.5 +/- 5.5 repetitions vs. -3.3 +/- 3.6 during T3, respectively, and -10.5 +/- 8.2 repetitions vs. -2.3 +/- 2.9 repetitions during T4, respectively). No differences in hormonal measures were seen between the groups. CK concentrations were significantly (P < 0.05) elevated at T3 for both groups, but continued to elevate (P < 0.05) at T4 for PL only. No significant group differences were noted for CK at any time point. Results indicate that a proprietary protein SUP consumed before and after a resistance training session significantly contributes to improvements in exercise recovery 24 and 48 h post-exercise.


Assuntos
Atletas , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Força Muscular/fisiologia , Treinamento Resistido , Levantamento de Peso/fisiologia , Adolescente , Adulto , Desempenho Atlético/fisiologia , Creatina Quinase/sangue , Método Duplo-Cego , Humanos , Hidrocortisona/sangue , Masculino , Análise por Pareamento , Proteínas do Leite/administração & dosagem , Medição da Dor , Testosterona/sangue , Fatores de Tempo , Proteínas do Soro do Leite , Adulto Jovem
11.
Int J Sport Nutr Exerc Metab ; 19(2): 172-85, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19478342

RESUMO

The effect of 10 wk of protein-supplement timing on strength, power, and body composition was examined in 33 resistance-trained men. Participants were randomly assigned to a protein supplement either provided in the morning and evening (n = 13) or provided immediately before and immediately after workouts (n = 13). In addition, 7 participants agreed to serve as a control group and did not use any protein or other nutritional supplement. During each testing session participants were assessed for strength (one-repetition-maximum [1RM] bench press and squat), power (5 repetitions performed at 80% of 1RM in both the bench press and the squat), and body composition. A significant main effect for all 3 groups in strength improvement was seen in 1RM bench press (120.6 +/- 20.5 kg vs. 125.4 +/- 16.7 at Week 0 and Week 10 testing, respectively) and 1RM squat (154.5 +/- 28.4 kg vs. 169.0 +/- 25.5 at Week 0 and Week 10 testing, respectively). However, no significant between-groups interactions were seen in 1RM squat or 1RM bench press. Significant main effects were also seen in both upper and lower body peak and mean power, but no significant differences were seen between groups. No changes in body mass or percent body fat were seen in any of the groups. Results indicate that the time of protein-supplement ingestion in resistance-trained athletes during a 10-wk training program does not provide any added benefit to strength, power, or body-composition changes.


Assuntos
Composição Corporal/efeitos dos fármacos , Suplementos Nutricionais , Força Muscular/efeitos dos fármacos , Proteínas/administração & dosagem , Treinamento Resistido , Registros de Dieta , Esquema de Medicação , Ingestão de Energia , Humanos , Masculino , Nitrogênio/urina , Adulto Jovem
12.
Nutr Res ; 28(1): 31-5, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19083385

RESUMO

The purpose of this study was to examine the effect of 30 days of beta-alanine supplementation in collegiate football players on anaerobic performance measures. Subjects were randomly divided into a supplement (beta-alanine group [BA], 4.5 g x d(-1) of beta-alanine) or placebo (placebo group [P], 4.5 g x d(-1) of maltodextrin) group. Supplementation began 3 weeks before preseason football training camp and continued for an additional 9 days during camp. Performance measures included a 60-second Wingate anaerobic power test and 3 line drills (200-yd shuttle runs with a 2-minute rest between sprints) assessed on day 1 of training camp. Training logs recorded resistance training volumes, and subjects completed questionnaires on subjective feelings of soreness, fatigue, and practice intensity. No difference was seen in fatigue rate in the line drill, but a trend (P = .07) was observed for a lower fatigue rate for BA compared with P during the Wingate anaerobic power test. A significantly higher training volume was seen for BA in the bench press exercise, and a trend (P = .09) for a greater training volume was seen for all resistance exercise sessions. In addition, subjective feelings of fatigue were significantly lower for BA than P. In conclusion, despite a trend toward lower fatigue rates during 60 seconds of maximal exercise, 3 weeks of beta-alanine supplementation did not result in significant improvements in fatigue rates during high-intensity anaerobic exercise. However, higher training volumes and lower subjective feelings of fatigue in BA indicated that as duration of supplementation continued, the efficacy of beta-alanine supplementation in highly trained athletes became apparent.


Assuntos
Fadiga/prevenção & controle , Futebol Americano , Resistência Física/fisiologia , Levantamento de Peso/fisiologia , beta-Alanina/farmacologia , Adaptação Fisiológica , Limiar Anaeróbio , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Masculino , Força Muscular/fisiologia , Inquéritos e Questionários , Adulto Jovem , beta-Alanina/administração & dosagem
13.
J Strength Cond Res ; 22(3): 874-82, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18438227

RESUMO

The effect of a pre-exercise energy sport drink on the acute hormonal response to resistance exercise was examined in eight experienced resistance trained men. Subjects were randomly provided either a placebo (P: maltodextrin) or the supplement (S: combination of branched chain amino acids, creatine, taurine, caffeine, and glucuronolactone). Subjects performed 6 sets of no more than 10 repetitions of the squat exercise at 75% of their 1 repetition maximum (1RM) with 2 minutes of rest between sets. Blood draws occurred at baseline pre-exercise, immediately post- (IP), 15 minutes post- (15P), and 30-minutes post (30P) exercise for measurement of serum growth hormone, total and free testosterone, cortisol, and insulin concentrations. Although significant differences were seen only at set 5, the total number of repetitions and training volume tended (p = 0.08) to be higher with S compared to P. Serum growth hormone and insulin concentrations were significantly higher at 15P and IP, respectively, in S compared to P. Results suggest that a pre-exercise energy S consumed 10 minutes before resistance exercise can enhance acute exercise performance by increasing the number of repetitions performed and the total volume of exercise. The enhanced exercise performance resulted in a significantly greater increase in both growth hormone and insulin concentrations, indicating an augmented anabolic hormone response to this pre-exercise S.


Assuntos
Suplementos Nutricionais , Hormônio do Crescimento/metabolismo , Insulina/metabolismo , Levantamento de Peso/fisiologia , Adulto , Aminoácidos Essenciais/administração & dosagem , Análise de Variância , Área Sob a Curva , Análise Química do Sangue , Cafeína/administração & dosagem , Creatina/administração & dosagem , Estudos Cross-Over , Método Duplo-Cego , Ingestão de Líquidos , Ingestão de Energia , Humanos , Masculino , Educação Física e Treinamento/métodos , Probabilidade , Valores de Referência , Sensibilidade e Especificidade , Taurina/administração & dosagem
14.
Med Sci Sports Exerc ; 40(1): 15-24, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18091024

RESUMO

PURPOSE: To examine nutritional supplementation and anabolic steroid (AS) use in adolescent males and females in a multistate, cross-regional study. A secondary purpose of the study was to investigate the knowledge, beliefs, and sources of education on nutritional supplementation and AS in these students. METHODS: A confidential self-report survey was administered to 3248 students representing grades 8-12 in 12 states in the continental United States by their teachers during homeroom or physical education class. RESULTS: Use of at least one supplement was reported by 71.2% of the adolescents surveyed. The most popular supplements used were multivitamins and high-energy drinks. The use of supplements to increase body mass and strength, and to reduce body fat or mass, increased across grade and was more prevalent in males than females. The number of students that self-reported AS use was 1.6% (2.4% males and 0.8% females). The number of supplements used was related to AS use among adolescents, and this effect was greater among males. Adolescents also seemed willing to take more risks with supplements to achieve their fitness or athletic goals, even if these risks reduced health or caused premature death. CONCLUSION: This study demonstrates that reliance on nutritional supplements increases as adolescents mature. The apparent willingness of adolescents to use a supplement that may harm their health or shorten their life highlights the need for greater involvement of teachers, coaches, and physicians to provide continued education on the risks and benefits associated with nutritional supplementation and AS use.


Assuntos
Anabolizantes , Androgênios , Suplementos Nutricionais , Comportamentos Relacionados com a Saúde , Estado Nutricional , Assunção de Riscos , Adolescente , Fatores Etários , Feminino , Humanos , Masculino , Aptidão Física , Fatores Sexuais , Inquéritos e Questionários
15.
Int J Sport Nutr Exerc Metab ; 17(6): 608-23, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18156665

RESUMO

The authors aimed to examine the acute hormonal and performance responses to resistance exercise with and without prior consumption of an amino acid/creatine/energy supplement. Eight men performed a resistance-exercise protocol at baseline (BL), 20 min after consuming a supplement (S) consisting of essential amino acids, creatine, taurine, caffeine, and glucuronolactone or a maltodextrin placebo (P). Venous blood samples were obtained before and immediately after (IP), 15 min (15P), and 30 min (30P) after each protocol. Area under the curve of resistance-exercise volume revealed that BL was significantly less than S (10%) and P (8.6%). For fatigue rate, only S (18.4% +/- 12.0%) was significantly lower than BL (32.9% +/- 8.4%). Total testosterone (TT) and growth hormone (GH) were significantly elevated at IP and 15P in all conditions. The GH response was significantly lower, however, in S and P than in BL. The TT and GH responses did not differ between S and P. These results indicated that a supplement consisting of amino acids, creatine, taurine, caffeine, and glucuronolactone can modestly improve high-intensity endurance; however, the anabolic-hormonal response was not augmented.


Assuntos
Aminoácidos/administração & dosagem , Creatina/administração & dosagem , Ingestão de Energia/fisiologia , Hormônio do Crescimento Humano/sangue , Testosterona/sangue , Levantamento de Peso/fisiologia , Adulto , Área Sob a Curva , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Masculino
16.
J Strength Cond Res ; 21(2): 456-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17530975

RESUMO

The purpose of this study was to compare nutritionally enriched JavaFit coffee (JF) to commercially available decaffeinated coffee (P) with regard to impact on endurance and anaerobic power performance in a physically active, college-aged population. Ten subjects (8 men, 2 women) performed two 30-second Wingate anaerobic power tests and 2 cycle ergometer tests (75% VO2 max) to exhaustion. Mean VO2 was measured during each endurance exercise protocol. Excess postexercise oxygen consumption (EPOC) and respiratory exchange ratio (RER) were recorded for 30 minutes following all exercise sessions. Area under the curve analysis was used to compare EPOC between JF and P for all exercise sessions. No differences were seen between JF and P in any of the power performance measures. However, time to exhaustion was significantly (p = 0.05) higher in JF (35.3 +/- 15.2 minutes) compared with P (27.3 +/- 10.7 minutes). No difference between JF and P were seen in EPOC in either the aerobic or anaerobic exercise sessions. A significant (p < 0.05) difference in average 30-minute postanaerobic power exercise RER was seen between JF (0.87 +/- 0.04) and P (0.83 +/- 0.03), but not following endurance exercise. A nutritionally-enriched coffee beverage appears to enhance time to exhaustion during aerobic exercise, but does not provide an ergogenic benefit during anaerobic exercise.


Assuntos
Cromo , Citrus , Café , Suplementos Nutricionais , Exercício Físico/fisiologia , Garcinia , Adulto , Limiar Anaeróbio/efeitos dos fármacos , Área Sob a Curva , Estudos Cross-Over , Método Duplo-Cego , Teste de Esforço , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Troca Gasosa Pulmonar/efeitos dos fármacos
17.
J Int Soc Sports Nutr ; 3: 35-41, 2006 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-18500961

RESUMO

BACKGROUND: The purpose of this study was to examine the effect of nutritionally enriched JavaFittrade mark (JF) coffee (450 mg of caffeine, 1200 mg of garcinia cambogia, 360 mg of citrus aurantium extract, and 225 mcg of chromium polynicotinate) on resting oxygen uptake (VO2), respiratory exchange ratio (RER), heart rate (HR), and blood pressure (BP) in healthy and physically active individuals. METHOD: Ten subjects (8 male, 2 female; 20.9 +/- 1.7 y; 178.1 +/- 10.4 cm; 71.8 +/- 12.1 kg) underwent two testing sessions administered in a randomized and double-blind fashion. During each session, subjects reported to the Human Performance Laboratory after at least 3-h post-absorptive state and were provided either 354 ml (1.5 cups) of freshly brewed JF or commercially available caffeinated coffee (P). Subjects then rested in a semi-recumbent position for three hours. VO2 and HR were determined every 5 min during the first 30 min and every 10 min during the next 150 min. BP was determined every 15 min during the first 30 min and every 30 min thereafter. Area under the curve (AUC) analysis was computed for VO2, whereas a session-average was calculated for RER, HR and BP. RESULTS: Initial analysis revealed no significant differences. However, seven of the ten subjects were considered responders to JF (had a higher AUC for VO2during JF than P). Statistical analysis showed the difference between JF and P (12%) to be significantly different in these responders. In addition, the average systolic BP was higher (p < 0.05) in JF (118 +/- 7 mmHg) than P (115 +/- 8 mmHg) in both the total sample and the subgroup of responders. No differences in average HR and average diastolic BP were observed between JF and P in both the total sample and the subgroup of responders. CONCLUSION: It appears that consuming a nutritionally-enriched coffee beverage may increase resting energy expenditure in individuals that are sensitive to the caffeine and herbal coffee supplement. In addition, this supplement also appears to affect cardiovascular dynamics by augmenting systolic arterial blood pressure.

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