Suleyman Patlar

The Effect of Glycerol Supplements on Aerobic and Anaerobic Performance of Athletes and Sedentary Subjects

Abstract The purpose of this study was to evaluate the effect of glycerol supplementation on aerobic and anaerobic exercise performance in sedentary subjects and athletes. The glycerol supplement treatments were as follows: 40 volunteers were selected and divided into two groups, sedentary and exercise groups. These two groups were further subdivided into two groups. The first group, the placebo (S), only consumed water; the second group (GS) consumed glycerol followed by water. Neither of these groups did any exercise for 20 days. The third and fourth groups consisted of the exercise group subjects; they were required to perform a 20-m shuttle run test every day for 20 days. The third group’s subjects, the placebo (E), only consumed water. The last group (GE) consumed glycerol followed by water. The Astrand Cycle Ergometer Test (ACET) was performed, and the Cosmed K4b2 portable gas analysis system was used to determine the aerobic capacity, while the Wingate Anaerobic Power Test (WAPT) was performed to determine the level of anaerobic power. The 20 Meter Shuttle Run Test (20MSRT) was performed after glycerol supplementation throughout the 20 days, and the exercise periods and distances were recorded. The glycerol supplement was found to have an increasing effect on aerobic and anaerobic performance in GS, E and GE. A similar effect was found for the covered distances and time in the same groups. However, an adverse effect was found on body weight.

Melatonin has a protective effect against lipid peroxidation in the bone tissue of diabetic rats subjected to acute swimming exercise

Abstract Aim The present study aimed to examine the effects of melatonin supplementation on lipid peroxidation in the bone tissue of diabetic rats subjected to acute swimming exercise. Methods The study was conducted on 80 Sprague-Dawley type adult male rats which were equally allocated to eight groups: group 1, general control; group 2, melatonin-supplemented control; group 3, melatonin-supplemented diabetic control; group 4, swimming control; group 5, melatonin-supplemented swimming; group 6, melatonin-supplemented diabetic swimming; group 7, diabetic swimming; group 8, diabetic control. In order to induce diabetes, the animals were subcutaneously injected with 40 mg/kg streptozotocin (STZ). The animals were supplemented with 3 mg/kg/day melatonin intraperitoneally (IP) for 4 weeks. At the end of the study, the animals were decapitated to collect bone tissue samples which were examined to find out the malondialdehyde (MDA) (nmol/g/protein) and glutathione (GSH) (mg/dL/g protein) levels. Results The highest MDA values in the bone tissue were found in groups 7 and 8. MDA levels in the bone tissue in groups 3 and 6 were lower than the levels in groups 7 and 8, but higher than those in all other groups. Groups 3, 5 and 6 had the highest bone tissue GSH values. On the other hand, the lowest GSH level was established in groups 7 and 8. Conclusion The results of the present study indicated that the cell damage caused by acute swimming exercise and diabetes in the bone tissue could be prevented by melatonin supplementation.

EFFECTS OF DIURNAL AND NOCTURNAL STRENUOUS EXERCISE ON SERUM MELATONIN LEVELS

Introduccion: Hay reportes de una posible relacion entre la melatonina, una hormona secretada por la glandula pineal, y el ejercicio. Objetivo: Este estudio tiene como objetivo investigar como el ejercicio extenuante diurno y nocturno afecta a los niveles de melatonina. Metodos: En el estudio participaron 10 hombres sanos sedentarios que no hacian ejercicio de forma activa. Los sujetos tenian una edad promedio de 22,20 ± 0,24 anos, altura promedio de 174,60 ± 2,33 cm, y peso promedio de 69,70 ± 2,42 kg. Dos muestras de sangre se obtuvieron de los sujetos, una en reposo, a las 10:00 horas de la manana y la otra inmediatamente despues del ejercicio vigoroso. Igualmente, las muestras de sangre se recogieron del mismo grupo de sujetos despues de 48 horas: a las 24:00 horas en reposo e inmediatamente despues del ejercicio extenuante. Las muestras se analizaron usando el metodo ELISA para determinar los niveles de melatonina en suero (pg/ml). Resultados: Mediante la comparacion de los valores en reposo y despues del ejercicio, se encontro que los valores sericos de melatonina se mantuvieron sin cambios despues del ejercicio. Ambos valores de melatonina en reposo y despues del ejercicio, medidos por la noche fueron mas altos en comparacion con los medidos durante el dia (p < 0,05). Conclusiones: Los altos niveles de melatonina encontrados en el estudio parecen ser el resultado del aumento de la liberacion de melatonina en la noche, y no del ejercicio. Los resultados de este estudio indican que el ejercicio extenuante realizado durante el dia o por la noche, no afecto significativamente los niveles de melatonina en suero.