Effects of Ramadan Fasting on Biochemical and Anthropometric Parameters in Physically Active Men


Khaled Trabelsi 1 , * , Kais el Abed 2 , John F. Trepanowski 3 , Stephen R. Stannard 4 , Zohra Ghlissi 1 , Hanene Ghozzi 1 , Liwa Masmoudi 1 , Kamel Jammoussi 5 , Ahmed Hakim 1

1 Laboratory of Pharmacology, Faculty of Medicine, University of Sfax, Tunisia

2 Laboratory of Cardio-Circulatory, Respiratory, Metabolic and Hormonal Adaptations to the Muscular Exercise, Faculty of Medicine Ibn El Jazzar, Tunisia

3 Cardiorespiratory/Metabolic Laboratory, University of Memphis, Memphis, USA

4 Institute of Food, Nutrition and Human Health, Massey University, New Zealand

5 Department of Biochemistry of the Hedi Chaker University Hospital, Tunisia

How to Cite: Trabelsi K, el Abed K, Trepanowski J F, Stannard S R, Ghlissi Z, et al. Effects of Ramadan Fasting on Biochemical and Anthropometric Parameters in Physically Active Men, Asian J Sports Med. Online ahead of Print ; 2(3):34775. doi: 10.5812/asjsm.34775.


Asian Journal of Sports Medicine: 2 (3); 134-144
Published Online: August 31, 2011
Article Type: Research Article
Received: February 6, 2011
Accepted: May 19, 2011


Purpose: The aim of this study was to assess the effects of Ramadan fasting on several biochemical and anthropometric parameters in physically active men by comparing fasters and nonfasters before, during, and after Ramadan.

Methods: Eighteen physically active men (10 fasters and 8 nonfasters) participated in this study. Subjects visited the laboratory for a total of four sessions on the following occasions: three days before Ramadan (Bef-R), the 15th day of Ramadan (Mid-R), the 29th day of Ramadan (End-R), and 21 days after Ramadan (Post-R). During each session, subjects underwent anthropometric measurements, completed a dietary questionnaire and provided a fasting blood sample.

Results: Body weight and body fat percentage decreased in fasters by 1.9% (P<0.001) and 6.2% (P=0.003), respectively, but increased in nonfasters by 2.2% (P<0.001) and 10.2% (P=0.001), respectively, from Bef-R to End-R. Fasters hematocrit and hemoglobin increased by 5.3% (P<0.001) and 6.3% (P=0.01), respectively, from Bef-R to End-R, while neither of these parameters changed in nonfasters. Fasters experienced an increase in the following parameters from Bef-R to End-R: urea (8.7%; P<0.001), creatinine (7.5%; P<0.001), uric acid (12.7%; P<0.001), serum sodium (1.9%; P<0.001), serum chloride (2.6%; P<0.001) and high-density lipoprotein cholesterol (27.3%; P<0.001). Of these parameters, only creatinine increased (4.4%; P=0.01) in nonfasters.

Conclusion: We conclude that Ramadan fasting lowers body weight and body fat percentage and can elevate high-density lipoprotein cholesterol in physically active men. However, practicing aerobic exercise during a hot and humid Ramadan month can induce a state of dehydration marked by an increase in some renal function markers and serum electrolytes.

Full Text

Full text is available in PDF

© 2011, Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/) which permits copy and redistribute the material just in noncommercial usages, provided the original work is properly cited.