Lassaad Chtourou

Possible gastrointestinal disorders for athletes during Ramadan: an overview

Abstract Ramadan is considered to be the month of the stomach break. It has been reported that Ramadan has some health benefits. In most Muslims countries, there is a huge modification in the diet during this month. These changes could induce some gastrointestinal (GI) disorders (e.g. diarrhea, cramps, fullness, nausea). The aims of the present overview were to present some challenges that could be observed for athletes during the training sessions or competition and present some practical recommendations to avoid GI disorders during Ramadan. Based on previous studies, we could advance that the prevalence of GI disorders will be more pronounced when athletes travel for international competitions during Ramadan. Besides, GI disorders are more frequent for athletes when there is a huge modification in the training load. Dehydration observed during Ramadan is one of the factors that may induce GI disorders. The latter could be exacerbated by sweat loss during training sessions. Carbohydrate is frequently used by athletes to improve performance and is associated with some GI disorders. Therefore, during Ramadan, coaches and athletes should be advised to maintain the same diet and a good hydration as before the fasting month, and avoid air travel when preparing for competitions.

Effect of Ramadan fasting on feelings, dietary intake, rating of perceived exertion and repeated high intensity short-term maximal performance

ABSTRACT The present study was designed to investigate the effect of Ramadan fasting on feelings, dietary intake, rating of perceived exertion (RPE) and repeated high-intensity short-term maximal performance. Thirteen physically active men (age: 21.2 ± 2.9 years, height: 175.6 ± 5.6 cm, body-mass: 72.4 ± 8.6 kg) performed a 5-m shuttle run test (6 × 30-s + 35-s of recovery in-between) during five experimental periods: fifteen days before Ramadan (BR), the first ten days of Ramadan (FR), the last ten days of Ramadan (ER), ten days after Ramadan (AR10) and 20 days after Ramadan (AR20). The study was carried out in Tunisia during the 2016 Ramadan month. During the 5-m shuttle run test, higher distance (HD), total distance (TD) and fatigue index (FI) were recorded. RPE was determined after a 5-min warm-up and after each repetition of the 5-m shuttle run test (the mean RPE score during the test was calculated). Moreover, a feelings scale (FS) was used after the warm-up and after the end of the 5-m shuttle run test. During the five experimental periods, dietary intake was assessed. The results showed that HD, TD and FI during the 5-m shuttle run test were not affected by Ramadan observance (p > 0.05). Likewise, FS scores recorded after the warm-up and the 5-m shuttle run test were not affected by Ramadan fasting (p > 0.05). However, mean RPE scores during the 5-m shuttle run test were significantly lower at ER (4.06 UA), AR10 (3.86 UA) and AR20 (3.71 UA) in comparison to BR (4.51 UA) (p < 0.05). The results showed also that Ramadan fasting has no adverse effect on energy intake, protein (g and %), fat (g and %) and carbohydrate (g). However, the fractional contribution of carbohydrate was significantly higher AR10 than FR (53.1% vs. 45.8%) and ER (53.1% vs. 46.5%) and AR20 than FR (5.92% vs. 45.8%) (p < 0.05). In conclusion, Ramadan fasting has no adverse effect on feelings, dietary intake, and short-term maximal performance. However, the RPE during repeated high intensity short-term maximal exercise was reduced AR20 in comparison to ER. Abbreviations: AR: After Ramadan; AR10: Ten days after Ramadan; AR20: Twenty days after Ramadan; BR: Fifteen days before Ramadan; ER: Last ten days of Ramadan; FI: Fatigue index; FR: First ten days of Ramadan; FS: Feelings scale; HD: Higher distance; PSQI: The Pittsburgh Sleep Quality Index; RPE: Rating of Perceived Exertion Scale; TD: Total distance

Potential role of liver enzymes levels as predictor markers of glucose metabolism disorders in Tunisian population

The relationship between liver enzymes and T2D risk is inconclusive. We aimed to evaluate the association between liver markers and risk of carbohydrate metabolism disorders, as well as their discriminatory power, for T2D prediction. This cross-sectional study enrolled 216 participants classified as normoglycemic, prediabetic, newly diagnosed diabetics, and diagnosed diabetics. All participants underwent anthropometric and biochemical measurements. The relationship between hepatic enzymes and glucose metabolism markers was evaluated by analyses of covariance. The associations between liver enzymes and incident carbohydrate metabolism disorders were analyzed through logistic regression and their discriminatory capacity to predict T2D by ROC analysis. High AP, ALT, γGT, and AST levels were independently related to decreased insulin sensitivity. Interestingly, a higher AP level was significantly associated with an increased risk of prediabetes (p = 0.017), newly diagnosed diabetes (p = 0.004), and T2D (p = 0.007). An elevated γGT level was an independent risk factor for T2D (p = 0.032) and undiagnosed T2D (p = 0.010) in prediabetic and normoglycemic subjects, respectively. In ROC analysis, AP was a powerful predictor of incident diabetes and significantly improved T2D prediction. Liver enzymes within the normal range, specifically AP levels, are associated with increased risk of carbohydrate metabolism disorders and significantly improved T2D prediction.

Genetic association and phenotypic correlation of TLR4 but not NOD2 variants with Tunisian inflammatory bowel disease

The common association between NOD2/CARD15 and TLR4 gene variants with inflammatory bowel disease (IBD) has not been replicated in all studies. We studied the polymorphism of these two genes in Tunisian patients with IBD.