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Med Principles Pract 2002;11(suppl 2):41–46

Does Fasting during Ramadan Alter Body Composition, Blood Constituents and Physical Performance?

Ramadan J.
Department of Physiology, Faculty of Medicine, Kuwait University, Kuwait
email Corresponding Author

 goto top of outline Key Words

  • Ramadan fasting
  • Heart rate
  • Oxygen consumption
  • Blood pressure
  • Exercise
  • Body composition

 goto top of outline Abstract

Objective: To study the effect of Ramadan fast (RF) on body composition, plasma constituents, hematology, and cardiorespiratory responses to constant submaximal exercise. Subjects and Methods: Sixteen sedentary healthy Kuwaiti adult males were included in the study. The subjects were tested under thermo-neutral conditions during a spring-like month of Ramadan and 2 months thereafter. They were tested during the week before RF (Pre1); the last 3 days of RF (End1); the week before a non-Ramadan month (Pre2), and the last 3 days of the non-Ramadan month (End2). The following measurements were made: body composition, cellular and biochemical constituents of blood, heart rate, ventilatory responses and blood pressure. Results: No significant changes were observed in body composition, cellular and biochemical constituents of blood. The heart rate and ventilatory responses to the moderately intense bouts of submaximal aerobic exercise (∼70% of VO2max) were significantly reduced (p < 0.04) while systolic blood pressure increased (p < 0.05) by the end of RF. Conclusions: Ramadan fasting had no adverse effect on the subjects when performing aerobic exercise at submaximal level. The mild changes in cardiorespiratory responses could be due to dehydration, abstention from consumption of substances with negative inotropy and circadian rhythms.

Copyright © 2002 S. Karger AG, Basel

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 goto top of outline Author Contacts

Dr. Jasem Ramadan
Department of Physiology
Faculty of Medicine, Kuwait University
PO Box 24923, 13110 Safat (Kuwait)
Tel. +965 5319593, Fax +965 5338937, E-Mail

 goto top of outline Article Information

Received: Received: March 11, 2002
Revised: July 30, 2002
Number of Figures : 3, Number of Tables : 4, Number of References : 14

 goto top of outline Publication Details

Medical Principles and Practice
International Journal of the Kuwait University Health Sciences Centre A Publicationof the Academic Publications Council

Vol. 11, No. Suppl. 2, Year 2002 (Cover Date: Released November 2002)

Journal Editor: Farida Al Awadi, Kuwait
ISSN: 1011–7571 (print), 1423–0151 (Online)

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