تغییر در حجم پا، ترکیب بدن و وضعیت هیدراتاسیون در دوچرخه سواران مرد و زن ۲۴ ساعت بعد دوچرخه سواری کوهستان (مقاله لاتین)۴ اردیبهشت ۱۳۹۳
تغییرات پاسخ های قلبی و عروقی و زمان خستگی در اثر مصرف نوشابه های انرژی زا (مقاله لاتین)۴ اردیبهشت ۱۳۹۳
Giuseppe Potrick Stefani, Ramiro Barcos Nunes*, André Zuanazzi Dornelles, Jadson Pereira Alves, Marcella Ody Piva, Marlise Di Domenico, Cláudia Ramos Rhoden , Pedro Dal Lago
Background: Creatine supplementation is known to exert an effect by increasing strength in high intensity and short duration exercises. There is a hypothesis which suggests that creatine supplementation may provide antioxidant activity by scavenging Reactive Oxygen Species. However, the antioxidant effect of creatine supplementation associated with resistance training has not yet been described in the literature. Therefore, we investigated the effect of creatine monohydrate supplementation associated with resistance training over maximum strength gain and oxidative stress in rats.
Methods: Forty male Wistar rats (250-300 g, 90 days old) were randomly allocated into 4 groups: Sedentary (SED, n = ۱۰), Sedentary + Creatine (SED-Cr, n = ۱۰), Resistance Training (RT, n = ۱۰) and Resistance Training + Creatine (RT-Cr, n = ۱۰). Trained animals were submitted to the RT protocol (4 series of 10–۱۲ repetitions, 90 second interval, 4 times per week, 65% to 75% of 1MR, for 8 weeks).
Results: In this study, greater strength gain was observed in the SED-Cr, RT and RT-Cr groups compared to the SED group (P < ۰٫۰۰۱). The RT-Cr group showed a higher maximum strength gain when compared to other groups (P < ۰٫۰۰۱). Creatine supplementation associated with resistance training was able to reduce lipoperoxidation in the plasma (P < ۰٫۰۵), the heart (P < ۰٫۰۵), the liver (P < ۰٫۰۵) and the gastrocnemius (P < ۰٫۰۵) when compared to control groups. However, the supplementation had no influence on catalase activity (CAT) in the analyzed organs. Only in the heart was the CAT activity higher in the RT-Cr group (P < ۰٫۰۵). The activity of superoxide dismutase (SOD) was lower in all of the analyzed organs in the SED-Cr group (P < ۰٫۰۵), while SOD activity was lower in the trained group and sedentary supplemented group (P < ۰٫۰۵).
Conclusions: Creatine was shown to be an effective non-enzymatic antioxidant with supplementation alone and also when it was associated with resistance training in rats.
Keywords: : Creatine; Supplementation; Resistance training; Oxidative stress; Lipoperoxidation; Antioxidant; Maximum strength; Rats