Aim: To quantify the physical workload  during the Ramadan 2015 (summer season) and to verify if this load changes significantly compared with
periods of non-fasting (in summer or winter seasons).
Methods: It was an18-month prospective cohort study conducted in a brickyard and a textile manufacturing company located in the governorate of
Monastir (Tunisia). It was based on the results of three  visits:  The first one (V1) was carried out in the month of Ramadan in the hot season, the
second visit  (V2) took place in the hot season outside of Ramadan and the third one   (V3) was in the cold season outside of Ramadan. During
these visits twelve male workers from each company matched by age filled out a questionnaire and went through a heart  rate  recording  according
to  the  recommendations  of  the  analysis  level  of  the International  Organization  for  Standardization  8996  enabling  the  evaluation  of  the
physical workload.
Results: During Ramadan, the physical workload was rated as «Medium» without any significant difference between the equivalent metabolic
rate means ± SD of the two groups (287.00±70.5 and 224.21±43.01W respectively in the brickyard and in the textile manufacturing company).
The working metabolic rate and the percentage of use of the maximum working capacity decreased in V2 and in V3 with no significant difference
between the two companies and the three measurement visits.
Conclusion: The physical workload in the month of Ramadan measured in two different activity sectors was found to be «Medium» and  did not
significantly differ from that noted in the non-fasting periods (outside of Ramadan).