Effects of aerobic exercise on urinary estrogens and progestagens in pre and postmenopausal women.

The purpose of this study was to elucidate the effect of 6 months of aerobic exercise on urinary excretion of female steroid hormones in pre and postmenopausal women and to check the basal values of urinary steroid. To this end, 20 premenopausal (age 45.56 ± 4.06 years) and 20 postmenopausal (age 52.27 ± 3.80 years) women, all sedentary, were studied before and after a supervised 6-month exercise training program (at 60-70% of maximal heart rate, 60 min/day, 3 days/week), based on aerobic dance. The exercise included standing on one leg, squatting, walking, and touching their heels. Before and after the program, anthropometric data and VO(2max) were measured and urine samples were collected and analyzed by gas chromatography/mass spectrometry (GC/Q-MS). Both, pre and postmenopausal women, improved their VO(2max) after the aerobic exercise program. Regarding the urinary steroids, on the one hand, important differences were observed between urinary estrogens and progestagens in pre and postmenopausal women in basal values. Estrone (P < 0.05), pregnanediol (P < 0.01), pregnanetriol (P < 0.05), and estriol (P < 0.01) levels were lower in postmenopausal women than in premenopausal women. On the other hand, the aerobic exercise program did not affect postmenopausal women in the same way as premenopausal women. After the exercise program, no changes in urinary steroid levels were observed in premenopausal women. However, the aerobic exercise program caused an increase in urinary excretion of pregnanediol (P < 0.05) and pregnanetriol (P < 0.05) in postmenopausal women.

Extracellular and Intracellular Concentrations of Molybdenum and Zinc in Soccer Players: Sex Differences.

Molybdenum (Mo) and zinc (Zn) play important roles in the process of adaptation to physical training. The aims of the present study were: (i) to analyze the differences in extracellular (plasma and urine) and intracellular (erythrocytes and platelets) Mo and Zn concentrations between sexes and (ii) to relate extracellular Zn concentrations with biomarkers of muscle damage and muscle mass. The present study involved 138 semi-professional soccer players divided according to sex: male (n = 68) and female (n = 70). Mo and Zn concentrations were determined by inductively coupled plasma mass spectrometry. Erythrocytes, platelets, creatine kinase (CK), and lactate dehydrogenase (LDH) values were also determined by automatic cell counter and spectrophotometric techniques. There were no sex differences in Mo and Zn intake. Male soccer players obtained higher values of erythrocytes, CK, and LDH (p < 0.05), and showed higher plasma and urinary concentrations of Mo and Zn (p < 0.05). Female soccer players showed relatively higher Zn concentrations in erythrocytes (p < 0.05). Finally, positive correlations were observed between extracellular Zn concentrations with CK, LDH and muscle mass. Extracellular concentrations of Mo and Zn were higher in male soccer players. However, the relative concentrations of Zn in relation to the number of erythrocytes were higher in female soccer players.

Effect of Handgrip Training in Extreme Heat on the Development of Handgrip Maximal Isometric Strength among Young Males.

The aim of this study was to evaluate the acute and adaptive effects of passive extreme heat (100 ± 3 °C) exposition in combination with a strength training protocol on maximal isometric handgrip strength. Fifty-four untrained male university students participated in this investigation. Twenty-nine formed the control group (NG) and 25 the heat-exposed group (HG). All the participants performed a 3-week isotonic handgrip strength training program twice a week with a training volume of 10 series of 10 repetitions with 45-s rest between series, per session. All the subjects only trained their right hand, leaving their left hand untrained. HG performed the same training protocol in hot (100 ± 3 °C) conditions in a dry sauna. Maximal isometric handgrip strength was evaluated each training day before and after the session. NG participants did not experience any modifications in either hand by the end of the study while HG increased maximal strength values in both hands (p < 0.05), decreased the difference between hands (p < 0.05), and recorded higher values than the controls in the trained (p < 0.05) and untrained (p < 0.01) hands after the intervention period. These changes were not accompanied by any modification in body composition in either group. The performance of a unilateral isotonic handgrip strength program in hot conditions during the three weeks induced an increase in maximal isometric handgrip strength in both hands without modifications to bodyweight or absolute body composition.

Acute effect of a maximum incremental test until exhaustion on malondialdehyde and antioxidant vitamins in plasma and erythrocytes in athletes.

INTRODUCTION: Background: it is well known that moderate or vigorous physical exercise produces an increase in free radicals. Aim: the aims of this study were to observe changes in malondialdehyde and antioxidant vitamins after a maximum incremental test, and to relate malondialdehyde and antioxidant vitamin values to performance parameters. Methods: eighty-four male athletes participated in this study. Participants performed a maximum incremental test until exhaustion on a treadmill. Malondialdehyde in plasma and antioxidant vitamins in plasma and erythrocytes were determined before and after the test. Results: in plasma, there was a decrease in malondialdehyde after the test. In erythrocytes, results showed increases in vitamin C and decreases in vitamin E after the test. Maximal oxygen uptake values were associated positively with vitamin C and negatively with malondialdehyde levels before the test. On the other hand, maximal oxygen uptake, total test time, and total test distance were positively related to the malondialdehyde values obtained after the test. Conclusions: a maximum incremental test did not produce any changes in plasma vitamins in athletes. However, it increased the levels of vitamin C in erythrocytes and decreased malondialdehyde values in plasma and vitamin E in erythrocytes. The levels of malondialdehyde, vitamin C and vitamin E were related to performance parameters. These results may be linked to the adaptation of antioxidant systems due to regular training.

INTRODUCCIÓN: Introducción: es sabido que el ejercicio físico moderado o vigoroso produce un aumento de radicales libres. Objetivos: los objetivos del estudio fueron: observar los cambios del malondialdehído y las vitaminas antioxidantes después de un test incremental máximo y relacionar los niveles de malondialdehído y vitaminas antioxidantes con parámetros de rendimiento. Métodos: ochenta y cuatro atletas masculinos participaron en el estudio. Los participantes realizaron un test incremental hasta la extenuación en un tapiz rodante. El malondialdehído en plasma y las vitaminas antioxidantes en plasma y en eritrocitos se determinaron antes y después del test incremental. Resultados: en el plasma hubo una disminución del malondialdehído después de la prueba incremental. En los eritrocitos, los resultados mostraron un aumento de la vitamina C y un descenso de la vitamina E después de la prueba. El consumo máximo de oxígeno se asoció positivamente con la vitamina C e inversamente con el malondialdehído antes del test. Por otro lado, el consumo máximo de oxígeno, el tiempo total del test y la distancia total durante el test se asociaron positivamente con los valores de malondialdehído obtenidos tras el test máximo. Conclusión: un test incremental máximo hasta la extenuación no produjo cambios en las vitaminas antioxidantes del plasma. Sin embargo, sí aumentó los niveles de vitamina C en los eritrocitos y redujo los niveles de malondialdehído en el plasma y los de vitamina E en los eritrocitos. Los niveles de malondialdehído, vitamina C y vitamina E se relacionaron con los parámetros de rendimiento. Estos resultados podrían estar relacionados con la adaptación de los sistemas antioxidantes debido al entrenamiento regular.

[Influence of soccer training on parameters of oxidative stress in erythrocytes]. / Influencia del entrenamiento en fútbol sobre parámetros de estrés oxidativo en eritrocitos.

INTRODUCTION: Introduction: the situations of stress among which physical exercise is included imply the possibility of an excessive production of free radicals and, by their action, an oxidative stress in the cells. To combat these effects, cells have defense mechanisms called antioxidant systems. Objectives: the objective of this study is to analyze the possible physiological changes in relation to parameters related to oxidative stress (MDA) and antioxidant activity (vitamin A, vitamin C and vitamin E) in the erythrocytes of professional soccer players, in comparison with untrained subjects. Methods: forty-two men divided into 21 soccer players (SG) (24.95 ± 3.03 years) and 21 sedentary students (CG) (23.71 ± 2.42 years) participated in the study. Their basal levels of MDA, vitamin C, vitamin A and vitamin E in erythrocytes, as well as their anthropometric characteristics and VO2max, were evaluated. Results: significant differences were observed in the anthropometric characteristics (p < 0.05) and VO2max (p > 0.01). SG presented statistically lower levels of MDA (p > 0.01), vitamin C (p > 0.05), vitamin E (p > 0.05) and vitamin A (p > 0.01). Conclusions: there is higher oxidative stress in soccer players than in sedentary players and it may be necessary to supplement with antioxidants in this group.

INTRODUCCIÓN: Introducción: cualquier situación de estrés, entre las cuales se incluye la realización de ejercicio físico, implica la posibilidad de una excesiva producción de radicales libres y, por acción de estos, un estrés oxidativo en las células. Para combatir estos efectos, las células disponen de unos mecanismos de defensa denominados sistemas antioxidantes. Objetivos: el objetivo del presente estudio se basa en analizar los posibles cambios fisiológicos en relación a parámetros relacionados con el estrés oxidativo (MDA) y con la actividad antioxidante (vitamina A, vitamina C y vitamina E) en los eritrocitos de jugadores profesionales de fútbol, en comparación con sujetos no entrenados. Métodos: cuarenta y dos varones divididos en 21 jugadores de fútbol (SG) (24,95 ± 3,03 años) y 21 estudiantes sedentarios (CG) (23,71 ± 2,42 años) participaron en el estudio. Se les evaluaron los niveles basales de MDA, vitamina C, vitamina A y vitamina E en eritrocitos, así como las características antropométricas y el VO2max. Resultados: se observaron diferencias significativas en las características antropométricas (p < 0,05) y VO2max (p > 0,01). SG presentó niveles estadísticamente inferiores de MDA (p > 0,01), vitamina C (p > 0,05), vitamina E (p > 0,05) y vitamina A (p > 0,01). Conclusiones: existe un mayor estrés oxidativo en jugadores de fútbol que en sedentarios, por lo que puede ser necesaria una suplementación con antioxidantes en este grupo.

Análisis nutricional en atletas de fondo y medio fondo durante una temporada deportiva.

Objetivo: el objetivo de este estudio fue analizar la ingesta nutricional de atletas de alto nivel de las especialidades de fondo y medio fondo, durante una temporada atlética, para detectar posibles deficiencias.Métodos: para llevar a cabo el estudio, se procedió a evaluar la dieta y las diferentes concentraciones de los macronutrientes (glúcidos, lípidos y proteínas) y los diferentes tipos de ácidos grasos, en cuatro momentos diferentes de la temporada: al inicio y a los 3, 6 y 9 meses de entrenamiento. La muestra estuvo constituida por un grupo formado por 23 atletas de fondo y medio fondo con un mínimo de 5 años de ntrenamiento, una carga semanal de entre 14-20 horas y un volumen de 100-120 km semanales. El procedimiento consistió en el registro nutricional durante un periodo de tres días consecutivos, en los cuatro momentos establecidos.Resultados: los resultados obtenidos muestran incrementos significativos (p < 0,05) en la ingesta de proteínas entre los 3-9 meses.Conclusión: la ingesta energética en atletas de fondo y medio fondo va aumentando a lo largo de la temporada deportiva, con cantidades de macronutrientes inferiores a las recomendadas por la comunidad científica, y con incrementos en la ingesta de proteínas en periodos de primavera y verano, coincidiendo con momentos de competición.