Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
J Sports Sci ; 32(9): 870-82, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24479464

RESUMEN

Basketball incorporates intense eccentric muscle activity that induces muscle microtrauma and an inflammatory response. This study investigated time-dependent inflammatory and performance responses during a weekly microcycle after a basketball match. Twenty elite-standard players underwent a trial that comprised a match followed by a 6-day simulated in-season microcycle. The trial was preceded by a control condition that did not have a match. Blood sampling and tests of maximal-intensity exercise performance and muscle damage occurred before each condition, immediately after the match and daily thereafter for 6 consecutive days. The match induced marked increases in heart rate, lactate, ammonia, glucose, non-esterified fatty acids and triglycerides. Performance deteriorated for 24-48 h after the match, whereas knee flexor and extensor soreness increased for 48 and 24 h post-match, respectively. Inflammatory (leukocytes, C-reactive protein, creatine kinase activity, adhesion molecules, cortisol, uric acid and cytokines) and oxidative stress (malondialdehyde, protein carbonyls, oxidised glutathione, antioxidant capacity, catalase and glutathione peroxidase) markers increased for ~24 h and subsided thereafter. Reduced glutathione declined for 24 h after exercise. These results suggest that a basketball match elicits moderate and relatively brief (~24-48 h) inflammatory responses, is associated with marked but short-lived performance deterioration, but is less stressful than other intermittent-type sports.


Asunto(s)
Rendimiento Atlético/fisiología , Baloncesto/fisiología , Inflamación/metabolismo , Músculo Esquelético/lesiones , Músculo Esquelético/metabolismo , Estrés Oxidativo , Amoníaco/sangre , Biomarcadores/sangre , Glucemia/metabolismo , Ácidos Grasos no Esterificados/sangre , Frecuencia Cardíaca , Humanos , Ácido Láctico/sangre , Masculino , Fuerza Muscular/fisiología , Mialgia/etiología , Educación y Entrenamiento Físico , Factores de Tiempo , Triglicéridos/sangre , Adulto Joven
2.
Eur J Appl Physiol ; 112(1): 49-57, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21479653

RESUMEN

The purpose of this study was to examine the effects of walking speed on the accuracy of measurement of steps, distance, and energy expenditure of two commercially available Omron pedometers [HJ-720IT-E2 (HJ-720) and HJ-113-E (HJ-113)]. Twenty-four untrained males (age, 22.7 ± 2.8 years; BMI, 24.38 ± 2.19 kg m(-2); body fat (%), 16 ± 2.2; VO(2max), 40.2 ± 6.5 ml kg(-1) min(-1)) and 18 females (age, 22.4 ± 2.9 years; BMI, 21.68 ± 2.43 kg m(-2); body fat (%), 23% ± 1.8; VO(2max), 35.9 ± 2.8 ml kg(-1) min(-1)) walked at five different velocities (54, 67, 80, 94 and 107 m min(-1)) on a treadmill in 5-min stages while wearing three types of pedometers: (a) HJ-720, (b) HJ-113, and (c) Yamax Digi-Walker SW-200 (YAM). Step-count for each pedometer was recorded at the end of each stage and compared with the value of a hand counter. Additionally, Omron pedometers were evaluated on their distance and energy expenditure (against VO(2) measurement with a gas-exchange analyzer) accuracy during each stage. HJ-720 and HJ-113 demonstrated high accuracy (r = 0.80-0.99) at all speeds. YAM underestimated step-count only at 54 m min(-1) (r = 0.46). HJ-720 and HJ-113 overestimated distance at slower speeds and underestimated distance at faster speeds, providing mean distance values that where to within 1.5-4% at 80 m min(-1). HJ-720 and HJ-113 underestimated energy expenditure (gross kilocalories) by 28%, when compared to indirect calorimetry. These results suggest that although the Omron HJ-720 and HJ-113 pedometers are accurate in the measurement of step-count, they demonstrate limited accuracy in the assessment of traveled distance and energy expenditure in a speed-dependent manner.


Asunto(s)
Actigrafía/instrumentación , Prueba de Esfuerzo/instrumentación , Monitoreo Ambulatorio/instrumentación , Esfuerzo Físico/fisiología , Caminata/fisiología , Adulto , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
3.
Eur J Appl Physiol ; 111(7): 1421-36, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21161266

RESUMEN

The aim of this study was to determine the effects of a simulated one-day Greco-Roman wrestling tournament on selected performance and inflammatory status indices. Twelve competitive wrestlers (22.1 ± 1.3 years) completed five matches according to the official Olympic wrestling tournament regulations following a ~6% weight loss. Performance measurements, muscle damage assessment, and blood sampling were performed before and following each match. Performance and inflammatory markers were not affected by weight loss. Mean wrestling heart rate reached ~85% of maximal and lactate concentration exceeded 17 mM. Fatigue rating demonstrated a progressive rise (P < 0.05) throughout the tournament, peaking in match 4. Performance demonstrated a progressive deterioration (P < 0.05) throughout the tournament, especially in the last two matches (P < 0.05), with upper-body measures exhibiting a greater decline (P < 0.05) and remaining below baseline (P < 0.05) until the end of the tournament. Muscle damage markers increased during the course of the tournament with upper limbs affected more. Creatine kinase activity, CRP levels, IL-6 concentration, and leukocyte counts increased (P < 0.05) progressively throughout the tournament, peaking in the last two matches. Cortisol, epinephrine and norepinephrine increased (P < 0.05) after each match, but testosterone declined (P < 0.05) progressively, reaching a nadir before the last match. This inflammatory response was accompanied by a marked increase (p < 0.05) in lipid peroxidation, protein oxidation, and antioxidant status markers indicating the development of oxidative stress. These results suggest that a one-day wrestling tournament may induce significant physiological demands on wrestlers that may adversely affect their performance and inflammatory status especially during the later stages of the tournament.


Asunto(s)
Adaptación Fisiológica/fisiología , Atletas , Rendimiento Atlético/fisiología , Lucha/fisiología , Adulto , Conducta Competitiva/fisiología , Fatiga/fisiopatología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Fuerza Muscular/fisiología , Enfermedades Musculares/etiología , Esfuerzo Físico/fisiología , Factores de Tiempo , Adulto Joven
4.
J Strength Cond Res ; 24(5): 1389-98, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20386477

RESUMEN

The objectives of the present investigation were to study the inflammatory and performance responses after an acute bout of intense plyometric exercise during a prolonged recovery period. Participants were randomly assigned to either an experimental group (P, n = 12) that performed intense plyometric exercises or a control group (C, n = 12) that rested. The delayed onset of muscle soreness (DOMS), knee range of motion (KROM), creatine kinase (CK) and lactate dehydrogenase (LDH) activities, white blood cell count, C reactive protein (CRP), uric acid (UA), cortisol, testosterone, IL-6, IL-1b strength (isometric and isokinetic), and countermovement (CMJ) and static (SJ) jumping performance were measured at rest, immediately postexercise and at 24, 48, 72, 96, and 120 hours of recovery. Lactate was measured at rest and postexercise. Strength remained unchanged throughout recovery, but CMJ and SJ declined (p < 0.05) by 8-20%. P induced a marked rise in DOMS, CK, and LDH (peaked 24-48 hours postexercise) and a KROM decline. An acute-phase inflammatory response consisting of leukocytosis (postexercise and at 24 hours), an IL-6, IL-1b, CRP, and cortisol elevation (during the first 24 hours of recovery) and a delayed increase of UA (peaked at 48 hours) and testosterone (peaked at 72 hours) was observed in P. The results of this investigation indicate that performing an acute bout of intense plyometric exercise may induce a short-term muscle damage and marked but transient inflammatory responses. Jumping performance seems to deteriorate for as long as 72 hours postexercise, whereas strength appears to remain unchanged. The acute-phase inflammatory response after a plyometric exercise protocol appears to follow the same pattern as in other exercise models. These results clearly indicate the need of sufficient recovery between successive plyometric exercise training sessions.


Asunto(s)
Reacción de Fase Aguda/fisiopatología , Ejercicio Físico/fisiología , Fatiga Muscular/fisiología , Reacción de Fase Aguda/sangre , Reacción de Fase Aguda/etiología , Adulto , Biomarcadores , Citocinas/sangre , Humanos , Articulación de la Rodilla , Pierna , Masculino , Fuerza Muscular/fisiología , Músculo Esquelético/lesiones , Rango del Movimiento Articular , Factores de Tiempo
5.
Med Sci Sports Exerc ; 42(10): 1809-18, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20216464

RESUMEN

PURPOSE: Hemodialyzed patients demonstrate elevated oxidative stress and reduced functional status. Exercise induces health benefits, but acute exertion up-regulates oxidative stress responses in patients undergoing hemodialysis. Therefore, the aim of the present study was to examine the effect of L-carnitine supplementation on i) exercise performance and ii) blood redox status both at rest and after exercise. METHODS: Twelve hemodialysis patients received either L-carnitine (20 mg kg(-1) i.v.) or placebo in a double-blind, placebo-controlled, counterbalanced, and crossover design for 8 wk. Participants performed an exercise test to exhaustion before and after supplementation. During the test, V˙O2, respiratory quotient, heart rate, and time to exhaustion were monitored. Blood samples, collected before and after exercise, were analyzed for lactate, malondialdehyde, protein carbonyls, reduced and oxidized glutathione, antioxidant capacity, catalase, and glutathione peroxidase activity. RESULTS: Blood carnitine increased by L-carnitine supplementation proportionately at rest and after exercise. L-carnitine supplementation increased time to fatigue (22%) and decreased postexercise lactate (37%), submaximal heart rate, and respiratory quotient but did not affect V˙O2peak. L-carnitine supplementation increased reduced/oxidized glutathione (2.7-fold at rest, 4-fold postexercise) and glutathione peroxidase activity (4.5% at rest, 10% postexercise) and decreased malondialdehyde (19% at rest and postexercise) and protein carbonyl (27% at rest, 40% postexercise) concentration. CONCLUSIONS: Data suggest that a 2-month L-carnitine supplementation may be effective in attenuating oxidative stress responses, enhancing antioxidant status, and improving performance of patients with end-stage renal disease.


Asunto(s)
Carnitina/administración & dosificación , Suplementos Dietéticos , Fallo Renal Crónico/fisiopatología , Estrés Oxidativo/efectos de los fármacos , Diálisis Renal , Antioxidantes , Catalasa/sangre , Ejercicio Físico/fisiología , Fatiga/tratamiento farmacológico , Fatiga/fisiopatología , Glutatión/sangre , Glutatión Peroxidasa/sangre , Frecuencia Cardíaca/fisiología , Humanos , Ácido Láctico/sangre , Masculino , Malondialdehído/sangre , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Carbonilación Proteica/efectos de los fármacos , Complejo Vitamínico B/sangre , Complejo Vitamínico B/farmacología
6.
J Strength Cond Res ; 24(12): 3278-86, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19996787

RESUMEN

Exercise-induced muscle damage is associated with an acute-phase inflammatory response characterized by phagocyte infiltration into muscle and free radical production. Although soccer includes intense eccentric muscle actions that cause muscle damage, the oxidative stress responses after a soccer game are currently unknown. The present investigation attempted to determine the responses of circulating levels of oxidative stress and antioxidant status markers during recovery from a soccer game. Twenty soccer players (experimental group) were assigned to 2 different teams that competed against each other (2 × 45 minutes). Ten other players served as controls (rested). Creatine kinase (CK) activity, uric acid, leukocyte count, malondialdehyde (MDA), protein carbnyls (PC), reduced (GSH) and oxidized glutathione (GSSG), antioxidant capacity (TAC), catalase, glutathione peroxidase activity (GPX), delayed-onset of muscle soreness (DOMS), and anaerobic performance (speed, vertical jump performance) were measured before and following (immediately post, 24 hours, 48 hours, 72 hours) the game. Performance deteriorated (2-17%, p < 0.05) throughout recovery. Leukocytosis developed (p < 0.05) immediately following the game and at 24 hours. Both CK and DOMS (3-8-fold, p < 0.05) increased from baseline and remained elevated (p < 0.05) through 48 hours. Thiobarbituric acid reactive substances (TBARS), PC, uric acid, GPX, and TAC increased (13-67%, p < 0.05) throughout recovery, whereas catalase was elevated (38%, p < 0.05) only immediately after the game. GSH/GSSG declined (17-75%, p < 0.05) throughout recovery. Our results suggest that oxidative stress is markedly upregulated by a soccer game, probably as a part of the exercise-induced inflammatory response, and is accompanied by a marked deterioration of anaerobic performance for as long as 72 hours.


Asunto(s)
Antioxidantes/metabolismo , Estrés Oxidativo , Fútbol/fisiología , Análisis de Varianza , Antropometría , Rendimiento Atlético , Biomarcadores/metabolismo , Estudios de Casos y Controles , Dieta , Radicales Libres/metabolismo , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Músculo Esquelético/metabolismo , Consumo de Oxígeno/fisiología , Fagocitos/fisiología , Recuperación de la Función , Estadísticas no Paramétricas , Factores de Tiempo , Regulación hacia Arriba , Adulto Joven
7.
Diabetes Care ; 32(12): 2161-7, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19729520

RESUMEN

OBJECTIVE: To evaluate the time course of leptin, adiponectin, and resting energy expenditure (REE) responses in overweight elderly males after acute resistance exercise protocols of various intensity configurations. RESEARCH DESIGN AND METHODS: Forty inactive men (65-82 years) were randomly assigned to one of four groups (n = 10/group): control, low-intensity resistance exercise, moderate-intensity resistance exercise, and high-intensity resistance exercise. Exercise energy cost, REE, leptin, adiponectin, cortisol, insulin, lactate, glucose, nonesterified fatty acids (NEFAs), and glycerol were determined at baseline, immediately after exercise, and during a 72-h recovery period. RESULTS: Exercise energy cost was lower in high-intensity than in low-intensity and moderate-intensity groups (221.6 +/- 8.8 vs. 295.6 +/- 10.7 and 281.6 +/- 9.8 kcal, P < 0.001). Lactate, glucose, NEFAs, and glycerol concentrations increased (P < 0.001) after exercise and returned to baseline thereafter in all groups. REE increased (P < 0.001) in all groups at 12 h in an intensity-dependent manner (P < 0.05). REE reached baseline after 48 h in the low- and moderate-intensity groups and after 72 h in the high-intensity group. Cortisol peaked in all active groups after exercise (P < 0.001) and remained elevated (P < 0.001) for 12 h. After adjustment for plasma volume shifts, leptin remained unaltered. Adiponectin concentration increased after 12 h and remained elevated for 24 h only in the high-intensity group (P < 0.001). CONCLUSIONS: Resistance exercise does not alter circulating leptin concentration but does increase REE and adiponectin in an intensity-dependent manner for as long as 48 and 24 h, respectively, in overweight elderly individuals. It appears that resistance exercise may represent an effective approach for weight management and metabolic control in overweight elderly individuals.


Asunto(s)
Adipoquinas/sangre , Metabolismo Energético/fisiología , Ejercicio Físico/fisiología , Sobrepeso/fisiopatología , Adiponectina/sangre , Anciano , Índice de Masa Corporal , Ácidos Grasos no Esterificados/sangre , Humanos , Insulina/sangre , Leptina/sangre , Masculino , Fuerza Muscular/fisiología , Sobrepeso/sangre , Sobrepeso/terapia , Descanso/fisiología , Grosor de los Pliegues Cutáneos , Relación Cintura-Cadera
8.
Hum Mov Sci ; 28(4): 543-50, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19443065

RESUMEN

The aim of this study was to examine the validity of the Bruininks-Oseretsky test of motor proficiency - short form (BOTMP-SF) [Bruininks, R. (1978). Bruininks-Oseretsky test of motor proficiency: Examiners manual. Circle Pines, MN] for the assessment of preschool aged children. Three-hundred and eighteen children 48-71months old (M=58.97months, SD=6.73) participated in the study. For the data analysis both an ANOVA and a MANOVA were applied with the total battery score and the 14 item scores being the dependent variables, respectively. Age was found to have a significant effect on both children's total battery score (F(3, 314)=110.65, p<.001, eta(2)=.68) and 13 item scores (minimum F(3, 314)=8.75, p<.001, minimum eta(2)=.145). Although the aforementioned results represent an evidence for the validity of the BOTMP-SF, a closer study on the score of each item revealed a high percentage of zero scores on four items. Task difficulty has caused a floor effect, constituting a threat to the validity of the preschoolers' motor assessment with the above battery. A modification of the battery items is suggested, so that the BOTMP-SF will give valid results for children 4-6years old.


Asunto(s)
Trastornos de la Destreza Motora/diagnóstico , Examen Neurológico/estadística & datos numéricos , Pruebas Neuropsicológicas/estadística & datos numéricos , Trastornos Psicomotores/diagnóstico , Factores de Edad , Preescolar , Femenino , Humanos , Masculino , Tamizaje Masivo/estadística & datos numéricos , Trastornos de la Destreza Motora/epidemiología , Equilibrio Postural , Trastornos Psicomotores/epidemiología , Valores de Referencia , Reproducibilidad de los Resultados , Caminata
9.
Dev Med Child Neurol ; 49(11): 846-8, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17979863

RESUMEN

This study compared the consistency of the Short Form (SF) and the Long Form (LF) of the Bruininks-Oseretsky Test of Motor Proficiency (BOTMP) in identifying preschool children with motor impairment (MI). One hundred and forty-four Greek preschool children participated (74 males, 70 females; mean age 5 y 2 mo [SD 5 mo], range 4 y 6 mo-5 y 6 mo). Although total SF and LF scores were highly correlated (r=0.85), paired t-tests indicated significant differences (t=-27.466, p=0.001). SF total scores (mean 58.72 [SD 7.28]) were higher than LF total scores (mean 47.38 [SD 9.43]). SF had low sensitivity (13.6%) and negative predictive value (72.5%) for identifying MI. The BOTMP-SF does not appear to be a valid test for the identification of MI in 5-year-old children.


Asunto(s)
Tamizaje Masivo/instrumentación , Trastornos de la Destreza Motora/diagnóstico , Encuestas y Cuestionarios , Preescolar , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...