Effects of Ramadan intermittent fasting on North African children's heart rate and oxy-haemoglobin saturation at rest and during sub-maximal exercise.
OBJECTIVE
To examine the effects of Ramadan intermittent fasting (RIF) on the heart rate (HR) and oxyhaemoglobin saturation levels (oxy-sat) of boys at rest and during a six-minute walking test (6MWT).


METHODS
Eighteen boys (age: 11.9 ± 0.8 years, height: 153.00 ± 8.93 cm, body mass: 55.4 ± 18.2 kg), who fasted the entire month of Ramadan in 2012 for the first time in their lives, were included. The experimental protocol comprised four testing phases: two weeks before Ramadan (pre-R), the end of the second week of Ramadan (R-2), the end of the fourth week of Ramadan (R-4), and 10 to 12 days after the end of Ramadan (post-R). During each phase, participants performed the 6MWT at approximately 15:00. HR (expressed as percentage of maximal predicted HR) and oxy-sat (%) were determined at rest and in each minute of the 6MWT.


RESULTS
R-4 HR values were lower than those of (1) pre-R (in the second minute), (2) R-2 (in the first and second minutes), and (3) post-R (in the first, second, fourth, fifth and sixth minutes). R-2 oxy-sat values were higher than those of pre-R (in the third minute) and those of post-R (in the fifth minute). Post-R oxy-sat values were lower than those of pre-R and R-4 in the fifth minute. These oxy-sat changes were not clinically significant since the difference was less than five points.


CONCLUSIONS
In non-athletic children, their first RIF influenced their heart rate data but had a minimal effect on oxy-sat values.
Laboratory of Physiology, Faculty of Medicine, University of Sousse, Tunisia; Faculty of Sciences, Bizerte, Carthage University, Tunisia.
Mohamed Amine
MA
Fenneni
Laboratory of Physiology, Faculty of Medicine, University of Sousse, Tunisia.
Imed
I
Latiri
High Institute of Sport and Physical Education, University of Gafsa, Gafsa, Tunisia.
Asma
A
Aloui
Laboratory of Physiology, Faculty of Medicine, University of Sousse, Tunisia; Department of Physiology and Functional Exploration, Farhat Hached University Hospital of Sousse, Tunisia.
Sonia
S
Rouatbi
Athlete Health and Performance Research Center, ASPETAR, Qatar Orthopedic and Sports Medicine Hospital, Qatar.
Karim
K
Chamari
Laboratory of Physiology, Faculty of Medicine, University of Sousse, Tunisia; Department of Physiology and Functional Exploration, Farhat Hached University Hospital of Sousse, Tunisia; Research Laboratory LR14ES05, Faculty of Medicine, University of Sousse, Tunisia. Email: helmi.bensaad@rns.tn.
Helmi Ben
HB
Saad