Training in the fasted state facilitates re-activation of eEF2 activity during recovery from endurance exercise.
ABSTRACT Nutrition is an important co-factor in exercise-induced training adaptations in muscle. We compared the effect of 6 weeks endurance training (3 days/week, 1-2 h at 75% VO(2peak)) in either the fasted state (F; n = 10) or in the high carbohydrate state (CHO, n = 10), on Ca(2+)-dependent intramyocellular signalling in young male volunteers. Subjects in CHO received a carbohydrate-rich breakfast before each training session, as well as ingested carbohydrates during exercise. Before (pretest) and after (posttest) the training period, subjects performed a 2 h constant-load exercise bout (~70% of pretest VO(2peak)) while ingesting carbohydrates (1 g/kg h(-1)). A muscle biopsy was taken from m. vastus lateralis immediately before and after the test, and after 4 h of recovery. Compared with pretest, in the posttest basal eukaryotic elongation factor 2 (eEF2) phosphorylation was elevated in CHO (P < 0.05), but not in F. In the pretest, exercise increased the degree of eEF2 phosphorylation about twofold (P < 0.05), and values returned to baseline within the 4 h recovery period in each group. However, in the posttest dephosphorylation of eEF2 was negated after recovery in CHO, but not in F. Independent of the dietary condition training enhanced the basal phosphorylation status of Phospholamban at Thr(17), 5'-AMP-activated protein kinase α (AMPKα), and Acetyl CoA carboxylase β (ACCβ), and abolished the exercise-induced increase of AMPKα and ACCβ (P < 0.05). In conclusion, training in the fasted state, compared with identical training with ample carbohydrate intake, facilitates post-exercise dephosphorylation of eEF2. This may contribute to rapid re-activation of muscle protein translation following endurance exercise.
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ABSTRACT: To examine the time-of-day and Ramadan fasting (RF) effects on serum apolipoprotein-AI (Apo-AI) and B (Apo-B), lipoprotein particles-a (Lp-a), high-sensitive C-reactive-protein (hs-CRP), and homocysteine (Hcy) during the Yo-Yo intermittent recovery test (YYIRT). Performance and biochemical measures were completed at two times-of-day (07:00 and 17:00 h), 1-week before RF (BR), the second week of RF (SWR), and the fourth week of RF (ER). For each session, subjects performed the YYIRT, and blood samples were taken before and 3-min after the test for biochemical measures. Fifteen soccer players. Total distance during the YYIRT, core temperature, body composition, dietary intakes, lipid (HDL-C, LDL-C, Apo-AI, B and Lp-a) and inflammatory (hs-CRP and Hcy) profiles. Performances during the YYIRT were higher in the evening than the morning BR (P < 0.05), but this fluctuation was not observed during RF. Moreover, LDL-C, ApoB, and Lp-a were stable throughout the daytime BR. However, during RF, they decreased at 17:00 h (P < 0.05). Likewise, HDL-C and Apo-AI increased after the exercise and were higher at 17:00 h BR (P < 0.001). Moreover, these parameters increased during RF (P < 0.01). Furthermore, Hcy and hs-CRP increased during the exercise (P < 0.01) with higher evening levels BR. During ER, the diurnal pattern of Hcy was inversed (P < 0.001). This study concluded that caloric restriction induced by RF seems to ameliorate lipid and inflammatory markers of cardiovascular health during intermittent exercise performed in the evening.PLoS ONE 11/2013; 8(11):e79873. DOI:10.1371/journal.pone.0079873 · 3.53 Impact Factor
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ABSTRACT: During the month of Ramadan, restriction of food and fluid intake for many hours before and during exercise, together with other Ramadan-associated negative factors such as sleep and mood swings can be a real challenge for fasting Muslim athletes to perform at their optimum level. Numerous studies have looked at the effects of Ramadan fasting on exercise responses and performances but these studies were mostly focused on the effects of the religious fast on acute training sessions. This review aims to present studies that analyzed the effects of fasting during the daytime period on chronic training and on the magnitude of training-induced adaptations over the Ramadan month. These studies were selected based on a set of criteria laid out by the authors to ensure valid comparison. The results from the small number of validated studies chosen, in contrast to our initial hypothesis, have indicated equivalent improvements in the magnitude of training-induced adaptations by both fasted and non-fasted individuals during post-Ramadan testing. The data suggest that in order for optimal training-induced adaptations to take place in Muslim fasted athletes during Ramadan, a training programme imposing a sufficient training load or stimulus with the presence of optimal nutrition and rest-recovery are key factors.Effects of Ramadan fasting on health and athletic performance, First edition edited by Hamdi Chtourou, 01/2014; OMICS Group eBook, OMICS Group Incorporation, California, USA..
Sport Sciences for Health 08/2014; 10(2-2):97-104. DOI:10.1007/s11332-014-0179-8