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1.
Eur J Appl Physiol ; 123(5): 1027-1039, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36629945

RESUMO

The effects of acute exercise on the cortisol awakening response (CAR), characterized by the rapid increase in cortisol concentrations within the 30-45 min following sleep offset has yet to be fully elucidated. Thus, our study investigated the effects of late-evening acute exercise on the CAR the following morning. We hypothesized that exercise would have a significant effect on the CAR the following morning. Twelve participants (mean (SD): age = 23 (4) years; mass = 76.8 (8.7) kg; height = 175.6 (5.0) cm; [Formula: see text]O2max = 48.9 (7.5) ml.kg-1.min-1) reported to the laboratory in the evening (1800 h) on two occasions and were randomly assigned to either exercise for one hour (70-75% of maximal power output) or rest condition. Blood and saliva samples were assayed for cortisol. Mixed-effects models determined the effect of exercise on the cortisol response post-waking in both blood and saliva. Participants demonstrated an average exercise-induced increase in circulating cortisol of 477.3%, with actual mean (SD) heart rate relative to maximum of 87.04% (6.14%). Model results demonstrated a negative effect for exercise condition when modeling the serum and salivary cortisol responses to awakening via a quadratic growth model (serum, ßCondition = - 42.26 [95% CI - 64.52 to - 20.01], p < 0.001; saliva, ßCondition = - 11.55 [95% CI - 15.52 to - 7.57], p < 0.001). These results suggest that cortisol concentrations in saliva and blood are significantly lower the morning following a prior evening exercise session. Therefore, the CAR may serve as a useful biomarker to monitor responses to exercise training, although the underlying mechanism for these decreases in the CAR should be investigated further.


Assuntos
Hidrocortisona , Sono , Humanos , Adulto Jovem , Adulto , Sono/fisiologia , Exercício Físico , Saliva , Vigília/fisiologia , Ritmo Circadiano/fisiologia
2.
J Sports Sci Med ; 18(3): 537-543, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31427876

RESUMO

Blood glucose and insulin responses to aerobic exercise are well defined yet the mechanisms effecting post-exercise insulin sensitization remain incomplete. Apelin has been reported to enhance glucose uptake and insulin sensitivity in vivo, but its role as a regulator of insulin sensitivity following acute aerobic exercise has not been investigated. Therefore, the purpose of this study was to investigate apelin's response to acute bouts of maximal and submaximal aerobic exercise and to elucidate apelin's influence on insulin sensitivity. Twelve (22.8 ± 2.9 yrs) healthy male (n = 7) and female (n = 5) subjects completed a graded to maximal (VO2max) and submaximal (70-75% VO2max) treadmill running bouts, as well as a 50g glucose challenge (GC). Blood was obtained at four time points (pre, post, 1hr post and 24hrs post) and assessed for glucose, insulin and apelin. Hepatic insulin sensitivity was assessed at rest and at 1hr and 24hrs via HOMA-IR and QUICKI indices. Results demonstrated that plasma apelin did not significantly change by condition (p = 0.324) or time (p = 0.633). Blood glucose and plasma insulin were significantly elevated immediately after VO2max and GC, but remained stable after submaximal exercise. Insulin sensitivity was significantly improved 1hr post-submaximal exercise, per HOMA-IR (p = 0.034) and QUICKI (p = 0.018) indices. Plasma apelin was significantly correlated with plasma insulin (r = 0.699, p = 0.011), HOMA-IR (r = 0.626, p = 0.029) and QUICKI (r = 0.660, p = 0.019) at rest. We conclude that, although hepatic insulin sensitivity was improved 1hr post-submaximal exercise, this exercise-induced insulin sensitization occurred independent of plasma apelin changes.


Assuntos
Apelina/sangue , Exercício Físico/fisiologia , Resistência à Insulina/fisiologia , Glicemia/metabolismo , Feminino , Hematócrito , Humanos , Insulina/sangue , Fígado/metabolismo , Masculino , Consumo de Oxigênio/fisiologia , Adulto Jovem
3.
J Strength Cond Res ; 33(3): 819-824, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30363034

RESUMO

Ehlert, AM, Cone, JR, Wideman, L, and Goldfarb, AH. Evaluation of a goalkeeper-specific adaptation to the Yo-Yo intermittent recovery test level 1: reliability and variability. J Strength Cond Res 33(3): 819-824, 2019-The Yo-Yo Intermittent Recovery Test Level 1 (YYIR1) has been shown to be a reliable test with strong correlations to physical match performance in field soccer players. However, the YYIR1 has less goalkeeper (GK) specificity. Therefore, the purpose of this study was to evaluate the test-retest reliability of a goalkeeper-specific adaptation of the YYIR1 (YYIR1-GK). Sixteen National Collegiate Athletic Association (NCAA) collegiate GKs (8 men and 8 women) performed the YYIR1-GK test twice (>4 and <7 days apart) to determine its reliability and variability. Subjects were tested at the same time of day and in a controlled indoor environment. Heart rate using polar monitors and rating of perceived exertion were obtained at the end of each stage of the YYIR1-GK. Test-retest reliability for each test was assessed by Pearson correlations, intraclass correlation coefficient (ICC), and coefficient of variation (CV). The YYIR1-GK was shown to have a strong test-retest reliability and low variability for male (r = 0.981, ICC = 0.980, CV = 5.82%) and female (r = 0.969, ICC = 0.956, CV = 9.60%) NCAA GKs, respectively. Male GKs performed significantly more stages and therein covered a greater distance in the YYIR1-GK than the female GKs (p = 0.05). This study suggests that the YYIR1-GK is a consistent assessment of intermittent fitness with high test-retest reliability and low variability in male and female NCAA GKs. It is suggested that larger numbers of GKs of various skill levels be evaluated in the future.


Assuntos
Atletas , Teste de Esforço/normas , Resistência Física/fisiologia , Futebol/fisiologia , Aclimatação , Adolescente , Desempenho Atlético/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Desempenho Físico Funcional , Reprodutibilidade dos Testes , Adulto Jovem
4.
Appl Physiol Nutr Metab ; 41(3): 332-4, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26859524

RESUMO

The purpose of the study was to determine the effects of partial vascular occlusion on irisin responses. Eight males completed trials of light (30% 1-repetition maximum (1RM)) resistance exercise (single biceps curls and calf presses) with partial vascular occlusion (LRO), moderate resistance (70% 1RM) with no occlusion (MR), and occlusion only (OO). Blood was collected before, after, and 15 min after exercise. Changes in circulating irisin were more affected during LRO than MR and OO trials.


Assuntos
Fibronectinas/sangue , Isquemia/sangue , Contração Muscular , Músculo Esquelético/irrigação sanguínea , Treinamento Resistido , Biomarcadores/sangue , Humanos , Isquemia/fisiopatologia , Masculino , Fluxo Sanguíneo Regional , Fatores de Tempo , Regulação para Cima , Adulto Jovem
5.
J Strength Cond Res ; 26(8): 2027-36, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21997450

RESUMO

An observed relationship between soccer match duration and injury has led to research examining the changes in lower extremity mechanics and performance with fatiguing exercise. Because many fatigue protocols are designed to result in substantial muscular deficits, they may not reflect the fatigue associated with sport-specific demands that have been associated with the increasing incidence of injury as the match progresses. Thus, the aim of this study was to systematically analyze the progressive changes in lower extremity mechanics and performance during an individualized exercise protocol designed to simulate a 90-minute soccer match. Previous match analysis data were used to systematically develop a simulated soccer match exercise protocol that was individualized to the participant's fitness level. Twenty-four National Collegiate Athletic Association Division I soccer players (12 men, 12 women) participated in 2 testing sessions. In the first session, the participants completed the Yo-Yo Intermittent Recovery Test Level 1 to assess their fitness level and determine the 5 submaximal running intensities for their soccer match simulation. In the second test session, progressive changes in the rating of perceived exertion (RPE), lower extremity performance (vertical jump height, sprint speed, and cutting speed), and movement mechanics (jumping vertical stiffness and terminal landing impedance) were measured during the soccer match simulation. The average match simulation running distance was 10,165 ± 1,001 m, consistent with soccer match analysis research. Time-related increases in RPE, and decrements in sprinting, and cutting speed were observed, suggesting that fatigue increased as the simulation progressed. However, there were no time-related decreases in vertical jump height, changes in lower extremity vertical stiffness in jumping, or vertical impedance during landing. Secondary analyses indicated that the coordinative changes responsible for the maintenance of stiffness and impedance differed between the dominant and nondominant limbs. Despite an increase in RPE to near exhaustive levels, and decrements in sprint and cutting performance, the participants were able to maintain jump performance and movement mechanics. Interestingly, the coordinative changes that allowed for the maintenance of vertical stiffness and impedance varied between limbs. Thus, suggesting that unilateral training for performance and injury prevention in soccer-specific populations should be considered.


Assuntos
Teste de Esforço/métodos , Futebol/fisiologia , Adolescente , Desempenho Atlético/fisiologia , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Extremidade Inferior/lesões , Extremidade Inferior/fisiologia , Masculino , Fadiga Muscular/fisiologia , Aptidão Física/fisiologia , Corrida/fisiologia , Futebol/lesões , Adulto Jovem
6.
Med Sci Sports Exerc ; 43(3): 501-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20689455

RESUMO

PURPOSE: This study tested the effectiveness of a fruit, berry, and vegetable concentrate (FVC), Juice Plus+® (NSA LLC, Collierville, TN), supplement on muscle function and oxidative stress in response to an acute bout of eccentric exercise (EE). METHODS: Forty-one healthy volunteers (age = 18-35 yr) were randomly assigned to either a placebo (P) or an FVC treatment taking capsules for 28 d (6 d(-1)) before EE and for the next 4 d. All subjects completed four sets of 12 repetitions of eccentric elbow flexion with their nondominant arm. Blood, muscle soreness (MS), range of motion (ROM), and maximal isometric force (MIF) of the elbow flexors were obtained before and immediately after exercise and at 2, 6, 24, 48, and 72 h postexercise. Plasma was analyzed for creatine kinase (CK), lipid hydroperoxides, malondialdehyde (MDA), and protein carbonyls (PC). Glutathione ratio was determined from whole-blood extracts. RESULTS: MS, ROM, MIF, and plasma CK demonstrated significant time effects independent of treatment. MS and plasma CK increased over time, whereas ROM and MIF decreased over time. There was a significant time and time × treatment effect for plasma PC and MDA. PC and MDA increased over time in the P group (P < 0.01) but were not significantly altered in the FVC-treated group at any time. No significant changes were noted in lipid hydroperoxides. The glutathione ratio was elevated immediately postexercise in both groups (P < 0.01) and elevated 6 h postexercise with P compared with the FVC-treated group (P < 0.05). CONCLUSION: This study reports that 4 wk of pretreatment with an FVC can attenuate blood oxidative stress markers induced by EE but had no significant impact on the functional changes related to pain and muscle damage.


Assuntos
Bebidas , Suplementos Nutricionais , Frutas , Músculo Esquelético/fisiologia , Estresse Oxidativo/fisiologia , Verduras , Adolescente , Adulto , Creatina Quinase/sangue , Cotovelo/fisiologia , Exercício Físico/fisiologia , Feminino , Glutationa/sangue , Humanos , Contração Isométrica/fisiologia , Peróxidos Lipídicos/sangue , Masculino , Malondialdeído/sangue , Força Muscular/fisiologia , Amplitude de Movimento Articular/fisiologia , Adulto Jovem
7.
J Sports Sci Med ; 10(2): 385-92, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-24149887

RESUMO

Genes can be activated or inhibited by signals within the tissues in response to an acute bout of exercise. It is unclear how a particular aerobic exercise bout may influence two muscles with similar actions to the activity. Therefore, the purposes of this investigation was to determine the gene response of selected genes involved in the "stress" response of the gastrocnemius (fast-twitch) and soleus (slow-twitch) muscles to a single two hour aerobic exercise bout in female Sprague-Dawley Rats at the 1 hour time point after the exercise. Exercised rats were run (n=8) for 2 hours at 20 m.min(-1) and one hour after the completion of the bout had their soleus (S) and gastrocnemius (G) muscles removed. Age and timed matched sedentary control rats had both S and G muscles removed also. RNA was isolated from all muscles. Real-time PCR analysis was performed on the following genes: NFκB, TNFα, and Atf3. GAPDH was used as the housekeeping gene for both muscles. S muscle showed more genes altered (n = 52) vs G (n = 26). NFκB gene expression was 0.83 ± 0.14 in the exercised S but was + 1.36 ± 0.58 in the exercised G and was not significantly different between the muscles. TNFα was altered 1.30 ± 0. 34 in the exercised S and 1.36 ± 0.71 in the exercised G and was not significantly different between the muscles. The gene Atf3 was significantly altered at 4.97 ± 1.01 in the exercised S, while it was not significantly altered in the exercised G (0.70 ± 0.55). This study demonstrates that an acute bout of aerobic exercise can alter gene expression to a different extent in both the S and G muscles. It is highly likely that muscle recruitment was a factor which influenced the gene expression in theses muscles. It is interesting to note that some genes were similarly activated in these two muscles but other genes may demonstrate a varied response to the same exercise bout depending on the type of muscle. Key pointsThe soleus (primarily slow twitch) and the gastrocnemius (primarily fast type) do not respond the same to a given exercise bout.There are gene transcription differences in stress genes between the 2 muscles.The results of exercise studies should be carefully viewed as the muscle used in measurements may not provide an adequate representation of all skeletal muscles.

9.
Appl Physiol Nutr Metab ; 32(6): 1124-31, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18059586

RESUMO

The purpose of this study was to determine the influence of gender and antioxidant supplementation on exercise-induced oxidative stress. Twenty-five men and 23 women ran for 30 min at 80% VO2 max, once before and once after 2 weeks of supplementation, and again after a 1-week wash-out period. Subjects were randomly assigned to either placebo (P), antioxidant (A: 400 IU vitamin E+1 g vitamin C), or a fruit and vegetable powder (FV) treatment. Blood was obtained at rest and immediately after exercise. Before supplementation, women had higher resting reduced glutathione, total glutathione, and plasma vitamin E compared with men. With both A and FV supplementations, plasma vitamin E gender differences disappeared. Protein carbonyls, oxidized glutathione, and malondialdehyde all increased similarly for both genders in response to exercise. Both A and FV attenuated the reduced glutathione decrease and the oxidized glutathione and protein carbonyls increase compared with P, with no gender differences. 8-hydroxydeoxyguanosine was lower with treatment A compared with FV and P only for men. Plasma vitamin C increased 39% (A) and 21% (FV) compared with P. These data indicate that women have higher resting antioxidant levels than men. Markers of oxidative stress increased similarly in both genders in response to exercise of similar intensity and duration. Two weeks of antioxidant supplementation can attenuate exercise-induced oxidative stress equally in both genders.


Assuntos
Antioxidantes/farmacologia , Suplementos Nutricionais , Exercício Físico/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , 8-Hidroxi-2'-Desoxiguanosina , Adolescente , Adulto , Aerobiose/efeitos dos fármacos , Aerobiose/fisiologia , Ácido Ascórbico/uso terapêutico , Proteínas Sanguíneas/metabolismo , Desoxiguanosina/análogos & derivados , Dieta , Método Duplo-Cego , Feminino , Glutationa/metabolismo , Humanos , Masculino , Malondialdeído/metabolismo , Carbonilação Proteica/efeitos dos fármacos , Caracteres Sexuais , Vitamina E/uso terapêutico
10.
J Electrocardiol ; 40(6 Suppl): S91-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17993337

RESUMO

Because myocardial ischemia induces QT/RR hysteresis, a correlation was hypothesized to exist between the extent of myocardial flow reduction and the magnitude of QT/RR hysteresis. Graded reductions in regional myocardial perfusion in the distribution of the left anterior descending coronary artery in open-chest pigs were used to model 1-vessel coronary artery disease. At each reduced level of left anterior descending coronary artery flow, the heart was electrically paced at progressively higher and lower rates between an initial control and maximum heart rate values. Digitized surface and intramyocardial electrograms and aortic pressure were used to measure QT/RR hysteresis, QT-interval adaptation, ST- and TQ-segment depression, and cardiac contractility. Intraexperimental blood samples were analyzed to assess inflammatory response (interleukin 6), oxidative stress (protein carbonyls), and myocyte injury (creatine kinase). Higher values of QT/RR hysteresis correlated with the severity of ischemia as assessed by TQ-segment depression in intramyocardial electrograms (P = .002). Lower flow rates were strongly associated with higher values of QT/RR hysteresis and slower QT-interval adaptation (P or= .02). Significant increases in systemic measures of inflammation, oxidative stress, and cardiac myocyte injury and major decrease in cardiac contractility preceded the most severe stages of flow reduction (30% and 20% of normal flow). We determined QT/RR hysteresis index thresholds corresponding to these mechanical and immunochemical responses. QT/RR hysteresis is a strong indicator of reduced myocardial perfusion and may provide information for noninvasive assessment of mechanical and immunochemical changes associated with early stages of coronary artery disease.


Assuntos
Velocidade do Fluxo Sanguíneo , Estenose Coronária/diagnóstico , Estenose Coronária/fisiopatologia , Diagnóstico por Computador/métodos , Eletrocardiografia/métodos , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/fisiopatologia , Animais , Circulação Coronária , Feminino , Frequência Cardíaca , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Suínos
11.
Med Sci Sports Exerc ; 39(9): 1515-21, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17805083

RESUMO

PURPOSE: This study was designed to identify changes in gene transcription that occur in the soleus muscle of untrained, 10-wk-old rats after a single aerobic exercise bout, and to identify which families of genes are most likely affected. METHODS: Rats were either run for 2 h and killed 1 h after exercise, or they remained sedentary and were killed at a matched time. Soleus muscles from each animal were examined using DNA microarrays, four genes related to RONS were analyzed by PCR, and two proteins were checked by Western blot analysis. RESULTS: The microarray identified 52 genes significantly altered by the exercise. The major gene families altered were metabolism, apoptosis, muscle contraction, transcription/cell signaling, tissue generation, and inflammation. Real-time PCR was performed on four genes (NFkappaB, TNFalpha, Atf3, and Mgst1), and the results from PCR analysis agreed with the microarray results. NFkappaB and TNFalpha were unaltered, whereas Atf3 was upregulated and Mgst1 was downregulated in the exercised soleus muscles. NFkappaB protein level was not different between the two groups, whereas Atf3 protein level was elevated in the exercise group according to Western blot analysis. CONCLUSIONS: These data suggest that 1 h after a 2-h run at approximately 65% of VO2max, the soleus muscle undergoes significant gene-transcript changes. Also, the genes examined with the real-time PCR matched the microarray results and the measured protein concentration concentrations agreed with gene-transcript data at the 1-h postexercise time point.


Assuntos
Músculo Esquelético/fisiologia , Condicionamento Físico Animal/fisiologia , Transcrição Gênica/fisiologia , Animais , Feminino , North Carolina , Análise de Sequência com Séries de Oligonucleotídeos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Transcrição Gênica/genética
12.
Med Sci Sports Exerc ; 38(6): 1098-105, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16775552

RESUMO

PURPOSE: To compare the effects of two antioxidant formulas on biomarkers of oxidative stress before and after aerobic exercise. METHODS: Aerobically trained men (N=25) and women (N=23) were assigned to one of three treatments: 400 IU of vitamin E+1 g of vitamin C (V; N=15), a fruit and vegetable juice powder concentrate (FV; N=16), or a placebo (P; N=17). Subjects ran for 30 min at 80% VO(2 max) before, after 2 wk of supplementation, and after a 1-wk washout period. Blood samples were taken before and immediately after exercise and analyzed for protein carbonyls (PC), malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), and vitamins C and E. RESULTS: The V treatment increased plasma vitamin C and E after 2 wk (P

Assuntos
Antioxidantes/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Ácido Ascórbico/sangue , Ácido Ascórbico/uso terapêutico , Biomarcadores/sangue , Proteínas Sanguíneas/análise , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangue , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Frutas , Humanos , Masculino , Malondialdeído/sangue , Placebos , Pós , Carbonilação Proteica , Verduras , Vitamina A/uso terapêutico , Vitamina E/sangue , Vitamina E/uso terapêutico
13.
Int J Sport Nutr Exerc Metab ; 15(3): 279-90, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16131698

RESUMO

Vitamin C supplementation (VC) (either 500 or 1000 mg/d for 2 wk) was compared to a placebo treatment (P) to ascertain if VC could influence oxidative stress. Twelve healthy males (25 +/- 1.4 y) were randomly assigned in a counter-balanced design with a 2-wk period between treatments. Data were analyzed using repeated measures ANOVA. Exercise intensity measures (VO(2), RER, RPE, HR, lactate) were similar across treatments. Resting blood oxidative-stress markers were unaffected by treatment. Exercise decreased total blood glutathione (TGSH) and reduced glutathione (GSH) and increased oxidized glutathione (GSSG) (P < 0.01) independent of treatment. Protein carbonyls (PC) increased 3.8 fold in the P (P < 0.01). VC attenuated the PC exercise response in a dose-dependent manner ( P < 0.01). Thiobarbituric acid reactive substances (TBARS) was not influenced by exercise (P = 0.68) or VC. These data suggest that VC supplementation can attenuate exercise-induced protein oxidation in a dose-dependent manner with no effect on lipid peroxidation and glutathione status.


Assuntos
Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Corrida/fisiologia , Adolescente , Adulto , Análise de Variância , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Estudos Cross-Over , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Glutationa/sangue , Glutationa/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/fisiologia , Masculino , Oxirredução , Estresse Oxidativo/fisiologia , Consumo de Oxigênio , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
14.
J Strength Cond Res ; 19(2): 276-85, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15903362

RESUMO

The purpose of this study was to compare oxidative modification of blood proteins, lipids, DNA, and glutathione in the 24 hours following aerobic and anaerobic exercise using similar muscle groups. Ten cross-trained men (24.3 +/- 3.8 years, [mean +/- SEM]) performed in random order 30 minutes of continuous cycling at 70% of Vo(2)max and intermittent dumbbell squatting at 70% of 1 repetition maximum (1RM), separated by 1-2 weeks, in a crossover design. Blood samples taken before, and immediately, 1, 6, and 24 hours postexercise were analyzed for plasma protein carbonyls (PC), plasma malondialdehyde (MDA), and whole-blood total (TGSH), oxidized (GSSG), and reduced (GSH) glutathione. Blood samples taken before and 24 hours postexercise were analyzed for serum 8-hydroxy-2'-deoxyguanosine (8-OHdG). PC values were greater at 6 and 24 hours postexercise compared with pre-exercise for squatting, with greater PC values at 24 hours postexercise for squatting compared with cycling (0.634 +/- 0.053 vs. 0.359 +/- 0.018 nM.mg protein(-1)). There was no significant interaction or main effects for MDA or 8-OHdG. GSSG experienced a short-lived increase and GSH a transient decrease immediately following both exercise modes. These data suggest that 30 minutes of aerobic and anaerobic exercise performed by young, cross-trained men (a) can increase certain biomarkers of oxidative stress in blood, (b) differentially affect oxidative stress biomarkers, and (c) result in a different magnitude of oxidation based on the macromolecule studied. Practical applications: While protein and glutathione oxidation was increased following acute exercise as performed in this study, future research may investigate methods of reducing macromolecule oxidation, possibly through the use of antioxidant therapy.


Assuntos
Exercício Físico/fisiologia , Estresse Oxidativo/fisiologia , Consumo de Oxigênio/fisiologia , 8-Hidroxi-2'-Desoxiguanosina , Adolescente , Adulto , Limiar Anaeróbio/fisiologia , Ciclismo/fisiologia , Biomarcadores/sangue , Proteínas Sanguíneas/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangue , Dieta , Glutationa/sangue , Humanos , Masculino , Malondialdeído/sangue , Músculo Esquelético/fisiologia
15.
Med Sci Sports Exerc ; 37(2): 234-9, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15692318

RESUMO

PURPOSE: This study was designed to ascertain the effects of a combination antioxidant therapy on plasma protein carbonyls (PC), malondialdehyde (MDA), and whole blood total (TGSH), oxidized (GSSG), and reduced (GSH) glutathione in non-resistance trained females after eccentric resistance exercise. METHODS: Eighteen women (aged 19-31 yr) were randomized in a double-blind manner to either an antioxidant supplement (N = 9; 400 IU vitamin E, 1 g vitamin C, and 90 mug selenium per day) or a lactose placebo (N = 9) for 14 d before and for 2 d after eccentric elbow flexor exercise. Blood samples taken before and immediately, 2, 6, 24, and 48 h postexercise were analyzed for PC, MDA, TGSH, and GSSG. RESULTS: No treatment by time interaction was noted for any variable, with all blood markers experiencing a change after the exercise in both conditions. Time main effects were observed for PC, MDA, and GSSG, with values elevated above preexercise after the eccentric exercise, whereas GSH concentration decreased after the eccentric exercise. Antioxidant supplementation resulted in a condition main effect for PC and MDA, with lower values compared with placebo. The antioxidant treatment attenuated the rise in both PC (75%) and MDA (100%). CONCLUSION: These data suggest that eccentric resistance exercise can increase blood biomarkers of oxidative stress in non-resistance trained females, and this vitamin E, C, and selenium supplementation can attenuate the rise in PC and MDA.


Assuntos
Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Exercício Físico , Estresse Oxidativo/efeitos dos fármacos , Adulto , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/farmacologia , Biomarcadores/sangue , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Glutationa/sangue , Glutationa/efeitos dos fármacos , Dissulfeto de Glutationa/sangue , Dissulfeto de Glutationa/efeitos dos fármacos , Humanos , Malondialdeído/sangue , Carbonilação Proteica/efeitos dos fármacos , Selênio/administração & dosagem , Selênio/farmacologia , Resultado do Tratamento , Vitamina E/administração & dosagem , Vitamina E/farmacologia , Saúde da Mulher
16.
Can J Appl Physiol ; 30(6): 677-89, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16485519

RESUMO

The purpose of this study was to determine if changes in oxidative stress biomarkers in blood and skeletal muscles are similar in normal and antioxidant supplemented rats after a downhill run. Sixty-six male Sprague-Dawley rats were pretreated with a normal rat diet or diet + antioxidants (2,000 mg vitamin C + 1,000 IU vitamin E/kg diet) for 2 weeks. Exercised rats ran 90 min on a rodent treadmill at a speed of 16 m/min at -16 degrees grade. Rats were sacrificed either at rest, immediately, 2 hrs, or 48 hrs postexercise. Malondialdehyde (MDA) and protein carbonyl (PC) concentrations and glutathione status in blood, vastus lateralis (white fast-twitch), vastus intermedius (red fast-twitch), and soleus (slow-twitch) muscles were determined. A significant increase from rest in PC occurred in plasma, vastus intermedius and soleus muscle 2 hrs after the downhill run (p < 0.05), with no changes observed at any other times postexercise. Antioxidant supplementation significantly decreased PC concentrations in both vastus intermedius and soleus muscles at all times combined (p < 0.05). MDA and glutathione status in blood and muscles were unaffected by either the downhill run or antioxidant treatment. For PC and MDA, the concentrations were lower in blood as compared to skeletal muscle, with the opposite finding for oxidized glutathione; however, the pattern of response postexercise was similar. These data indicate that (a) PC, but not MDA or oxidized glutathione, is elevated transiently following downhill running in male rats; (b) the elevation in PC postexercise occurs in plasma, vastus intermedius, and soleus muscles; (c) antioxidant therapy can attenuate PC in vastus intermedius, and soleus muscles; and (d) while the concentrations of oxidative stress biomarkers differ between blood and the various skeletal muscles, the pattern of response postexercise is similar.


Assuntos
Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Suplementos Nutricionais , Glutationa/metabolismo , Malondialdeído/metabolismo , Músculo Esquelético/metabolismo , Estresse Oxidativo/fisiologia , Condicionamento Físico Animal , Vitamina E/administração & dosagem , Animais , Glutationa/sangue , Membro Posterior , Masculino , Malondialdeído/sangue , Carbonilação Proteica/fisiologia , Ratos , Ratos Sprague-Dawley
17.
Int J Sport Nutr Exerc Metab ; 14(5): 550-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15673101

RESUMO

To examine the effects of an antioxidant treatment on blood lactate, protein carbonyls (PC), and glutathione status, 42 male rats were assigned to either a control treatment (water, C) or one of two Microhydrin treatments (added to water, MH I or MH II). Rats from each treatment were assigned to either exercise (60 min of running) or rest. A treatment-by-time interaction was noted for blood lactate, with elevations only in the C and MH I treatments post-exercise (approximately 2.54 and 2.5 mM, respectively). Both treatment and time main effects were noted for PC. Exercise resulted in an increase in PC for both Microhydrin treatments with significantly greater PC compared to C. Total blood glutathione was unaffected by treatment or exercise. Exercise increased the ratio of oxidized to total glutathione and the MH II treatment resulted in a greater ratio compared to the other treatments. In conclusion, MH II results in lower blood lactate, while resulting in an increase in the concentration of oxidized protein and glutathione, suggesting heightened oxidative stress.


Assuntos
Antioxidantes/farmacologia , Glutationa/sangue , Ácido Láctico/sangue , Condicionamento Físico Animal/fisiologia , Proteínas/metabolismo , Silicatos/farmacologia , Animais , Glutationa/metabolismo , Dissulfeto de Glutationa/sangue , Masculino , Proteínas/química , Proteínas/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio
18.
Med Sci Sports Exerc ; 34(3): 443-8, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11880808

RESUMO

PURPOSE: This study examined the effects of a single bout of high-intensity eccentric exercise (EE) on blood protein carbonyls, glutathione status, and muscle damage indicators to ascertain whether blood markers of oxidative stress are elevated at the time delayed onset of muscle soreness (DOMS) occurs. METHODS: Eight healthy men (26.5 +/- 1.5 yr) performed 60 eccentric contractions at approximately 135-150% dominant arm maximum isometric force (MIF) using their nondominant arm elbow flexors. DOMS, range of motion (ROM), MIF, and blood were obtained before, immediately after, and 24, 48, 72, and 96 h after the EE. Blood samples were analyzed for plasma creatine kinase (CK) activity, and protein carbonyls (PC), and erythrocyte glutathione status. RESULTS: A significant decrease in MIF occurred at all times after the EE. ROM decreased from 24 to 96 h, and DOMS increased 24 to 72 h in the nondominant arm as indicated by a repeated measure ANOVA. Plasma CK activity peaked at 72 h (1620 +/- 500 IU x L(-1)) compared with baseline (154 +/- 27 IU x L(-1). Erythrocyte-reduced glutathione (GSH) concentration was not significantly affected by the EE but tended to decrease 23% by 24 h and continued at this level for 96 h. Oxidized glutathione (GSSG) and total glutathione were unchanged over time. A significant increase in plasma PC occurred at 24 and 48 h after eccentric exercise. CONCLUSIONS: The results suggest that 60 EE at 135-150% MIF can result in DOMS, with decreased muscle function and increases in plasma PC at 24 and 48 h without alterations in blood glutathione status.


Assuntos
Exercício Físico/fisiologia , Estresse Oxidativo/fisiologia , Adulto , Creatina Quinase/sangue , Glutationa/sangue , Glutationa/metabolismo , Humanos , Masculino , Contração Muscular , Músculo Esquelético/metabolismo , Dor/metabolismo , Medição da Dor , Fatores de Tempo
19.
Pain ; 11(1): 1-8, 1981 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7029423

RESUMO

Aspirin can be an effective antipyretic, analgesic and anti-inflammatory agent, but unfortunately, its use in the elderly is often excessive [43]. In a survey by Gillies and Skyring, the overall prevalence of daily aspirin intake was greater in middle-age and older-age groups than for those of less than 40 years of age [16]. The elderly are susceptible to the advertising of non-prescription drugs and aspirin is frequently self-prescribed [8,31]. Age-related physiological changes modify the response to aspirin in the elderly. A higher incidence of drug reactions and interactions has been evidenced in this age group. The cases cited throughout this report substantiate the need for caution on the part of the geriatric patient and the physician in regard to aspirin therapy for the elderly.


Assuntos
Aspirina/efeitos adversos , Fatores Etários , Idoso , Aspirina/uso terapêutico , Interações Medicamentosas , Humanos , Dor/tratamento farmacológico , Úlcera Gástrica/induzido quimicamente
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