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Intense physical exercise is an important modifier of hormone metabolism. The aim of this study was to evaluate the variations in the urine profile of glucuroconjugated steroids (androgens, estrogens, and corticosteroids) as a consequence of a session of strength exercises. The subjects were a group (N = 20) of untrained male university students. They performed 3 sets of 10 repetitions, with a 3-minute recovery time between sets, at 70-75% of 1 repetition maximum (1RM). Four urine samples were collected per subject: before the session, immediately after, 3 hours after, and 48 hours after the session. They were assayed using a gas chromatograph coupled with a mass spectrometer. The concentrations of the different hormones were determined according to the urine creatinine level (ng steroid per mg creatinine). The substances assayed were testosterone, epitestosterone (Epit), androstenedione, dehydroepiandrosterone (DHEA), androsterone, etiocholanolone, [beta]-estradiol, estrone, tetrahydrocortisone (THE), and tetrahydrocortisol (THF). The results showed a significant decline after exercise with respect to the rested state in the urinary excretion of testosterone, Epit, DHEA, androsterone, and etiocholanolone. At 48 hours, there was a significant increase in the urinary excretion of Epit, androstenedione, androsterone, etiocholanolone, estrone, and THE. The androsterone + etiocholanolone/THE + THF ratio decreased after exercise, increased significantly (p < 0.05) at 3 hours, and returned to near resting levels at 48 hours. The data suggest that the performing a strength session at 70-75% of maximum strength provoked a state of fatigue in the subjects, from which they recovered 48 hours after the exercise. KEY WORDS urinary steroids; cieatinine, strength exercise, gas chromatogiaphy/mass spectrometry

Background: The aim of this study was to observe the concentrations of trace metals boron, lithium, rubidium, antimony, tin and strontium in the serum of athletes from different modalities and sedentary subjects and the possible influence that different energy sports training modalities can have on their concentration. Methods: Eighty professional athletes and 31 sedentary males participated in the present survey. All of them were living in Cáceres (Spain). Serum boron, lithium, rubidium, antimony, tin and strontium analysis was performed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Results: The results show higher concentrations in athletes on tin (p < 0.01), rubidium and antimony (p < 0.001) than the control group. In the case of tin, this item had the highest concentrations only in aerobic sports modalities. Regarding rubidium and antimony, the highest concentrations are found in athletes with lower oxygen consumption (aerobic-anaerobic) (p < 0.001), followed by anaerobic group (p < 0.001). Conclusion: Our research shows that, probably due to increased water and air intake, especially, trace elements rubidium, antimony and tin reveal major differences in serum concentration of athletes in relation to sedentary subjects. On the other hand, physical training does not change the serum concentration of Boron, Lithium and strontium. [ABSTRACT FROM AUTHOR]

The article discusses research which was conducted to assess the effect five milligrams/kilogram body mass caffeine had on maximal exercise and total fatty acid profile. Researchers evaluated 20 male subjects who ingested caffeine before participating in aerobic exercise. They found that the caffeine produced an ergogenic effect and that caffeine and improved exercise performance resulted in greater relative fat oxidation and post-exercise differences in fatty acid proportions.

Aerobic exercise is associated with changes in the blood profile of fatty acids. Caffeine is known to be a potential lipolytic agent. Hence, caffeine ingestion in addition to exercise might have an influence on fatty acids, with positive effects on health and performance. The aim of the present study, therefore, was to assess the effect of caffeine (5 mg · kg body mass-1) ingested before aerobic exercise on the total plasma fatty acid profile. In a crossover, double-blind, randomized study involving 20 untrained males ([image omitted] 43.57±6.48 ml · kg-1 · min-1), blood lactate concentration, plasma caffeine values, and plasma fatty acid profile were examined using chromatographic techniques before and after 30 min of steady-state cycle exercise at 75% [image omitted] under placebo and caffeine conditions. Ventilatory responses and substrate oxidation rates were determined during exercise and recovery. Ventilatory responses, lactate concentrations, and fat and carbohydrate oxidation rates were not affected by caffeine ingestion. Carbohydrate was the main substrate oxidized during steady-state trials under both conditions, although exercise increased blood saturated fatty acids (placebo: 28.30±5.90% vs. 31.09±4.59, P<0.05; caffeine: 28.88±4.12% vs. 29.60±4.56%). Unsaturated blood concentrations of oleic fatty acid trans (C18:1t) increased due to caffeine (placebo: 2.22±2.81% vs. 2.61±3.86%; caffeine 1.53±0.19% vs. 1.70±0.49%, P<0.05). In conclusion, the ingestion of caffeine prior to moderate-to-high aerobic exercise may not have a clear metabolic advantage under the conditions of the present study in untrained individuals, although it might influence some individual unsaturated fatty acids (C18:1t) despite low fat oxidation rates. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the urine profile of glucuroconjugated steroids in untrained men after a strength training session. Subjects of the study include a group of untrained male university students, who conducted 3 sets of repetitions with a recovery time of three minutes at 70-75% of one repetition maximum (1RM). It is found that performing a strength session at 70-75% of maximum strength could provoke a state of fatigue in the subjects, who have recovered after 48 hours.

The aim of the present study was to evaluate the basal concentrations of malondialdehyde (MDA) nonenzymatic antioxidants, such as ascorbic acid, α-tocopherol, and retinol in plasma or erythrocytes, and the plasma concentrations of 16 trace minerals in endurance athletes from Extremadura (Spain). In addition, we aimed to assess the possible relationships between some parameters related to cellular oxidative stress with plasma concentrations of some trace minerals. Sixty-two national long-distance men athletes participated in this study. The parameters related to oxidative stress and antioxidant activity were analyzed through high pressure liquid chromatography (HPLC), and trace minerals analysis was performed by inductively coupled plasma mass spectrometry (ICP-MS). We found that plasma MDA was positively correlated with selenium and rubidium. Plasma ascorbic acid was positively correlated with manganese and negatively correlated with cobalt and cadmium. Erythrocyte ascorbic acid was related to arsenic and cesium. Plasma α-tocopherol correlated with copper and manganese negatively and positively with arsenic. Erythrocyte α-tocopherol was positively related to copper, rubidium, and lithium. The findings show that athletes with a high degree of training should monitor their intake and concentrations of α-tocopherol for its fundamental role of neutralizing the excess of reactive oxygen species produced by exercise and the prooxidant effects of several minerals such as arsenic, copper, and lithium. [ABSTRACT FROM AUTHOR]

Background: The main objective of this study was to observe any changes and possible adaptations produced in MDA and antioxidants vitamins on plasma and erythrocytes in endurance male athletes among an athletic season (12 months)., Methods: Twenty three long and middle distance male athletes participated in this study. Basal MDA on plasma and antioxidant vitamins in plasma and erythrocytes were measured at four moments along the season (0, 3, 6 and 9 months). Fatty acid concentrations in erythrocytes were obtained to determine lipid peroxidation indexes., Results: In plasma, vitamin C suffered significant decreases at 3 and 6 months compared with the begin (P<0.01), and an increase at 9 months, compared with 3 months. On the other hand, vitamin A level was significantly lower at 9 months compared with the other periods (P<0.01 compared with 0 and 6 months; P<0.05 compared with 3 months). In erythrocytes, significant decreases were observed in vitamin E among the season at 6 months and an increase from 6 to 9 months (P<0.05). Vitamin A suffers a significant decrease in both for competitive periods, at 3 and 9 months, compared with the beginning of the season. The most of changes in lipid peroxidation indexes were produced along the firsts 3 months., Conclusions: 1) Physical training improves the antioxidant systems in order to reduce lipid peroxidation in trained athletes along the season; 2) PUFA/SFA ratios seem more reliable than MDA to observe oxidative stress.

Background: This study analyzes the effects of physical exercise on urinary collagen crosslinks, pyridinoline (PYD) and deoxipyridinoline (DPD), in women., Methods: Thirty premenopausal (PRE) and 40 postmenopausal (PST) women took part in a six month randomized controlled trial of moderate physical exercise. Moreover, skinfold thickness, muscle strength and flexibility were evaluated., Results: Basal values of urinary PYD and DPD were higher in postmenopausal women versus premenopausal women (P<0.01). Physical exercise increased in both groups urinary PYD levels (P<0.05) and urinary DPD levels in postmenopausal women (P<0.05). After the exercise program, no changes were observed in the levels of urinary DPD in premenopausal women. Significant improvements in flexibility, muscle strength and decrease in skinfolds thickness were observed in the exercise group. No changes were observed in non-exercise group., Conclusions: In conclusion, the physical activity program produced beneficial effects on muscle strength and flexibility and changes in the musculoskeletal system. Also, the physical activity program led to a non-pathological increase in the urinary elimination of bone reabsorption and collagen metabolism biomarkers.

Caffeine (1,3,7-trimethylxanthine) is an habitual substance present in a wide variety of beverages and in chocolate-based foods and it is also used as adjuvant in some drugs. The antioxidant ability of caffeine has been reported in contrast with its pro- oxidant effects derived from its action mechanism such as the systemic release of catecholamines. The aim of this work was to evaluate the effect of caffeine on exercise oxidative stress, measuring plasma vitamins A, E, C and malonaldehyde (MDA) as markers of non enzymatic antioxidant status and lipid peroxidation respectively. Twenty young males participated in a double blind (caffeine 5mg·kg- 1 body weight or placebo) cycling test until exhaustion. In the exercise test, where caffeine was ingested prior to the test, exercise time to exhaustion, maximum heart rate, and oxygen uptake significantly increased, whereas respiratory exchange ratio (RER) decreased. Vitamins A and E decreased with exercise and vitamin C and MDA increased after both the caffeine and placebo tests but, regarding these particular variables, there were no significant differences between the two test conditions. The results obtained support the conclusion that this dose of caffeine enhances the ergospirometric response to cycling and has no effect on lipid peroxidation or on the antioxidant vitamins A, E and C. Key PointsCaffeine ingestion may improve maximal aerobic performance in non trained men.Cellular oxidative damage is not altered by caffeine ingestion in maximal aerobic exercises.Antioxidant response to exercise, vitamins A, E and C, is not modified by caffeine action in maximal aerobic efforts.