For these remaining World Cup players, observing Ramadan has extra strings attached. (Celio Maielo, Wikimedia Commons)

Starting this Saturday night, Muslims must forgo food and drink from dawn until dusk - and athletes are not exempt. Because Ramadan is pegged to the lunar calendar, it begins a little earlier in the Gregorian calendar each year. It just happens that in 2014, its onset coincides with the opening of the second round.

Dozens of Muslim players remain in the tournament, including France’s Karim Benzema and Germany’s Mesut Ozil in addition to whole teams that hail from Muslim countries, such as Algeria. Especially in the highly hot and humid climate of Brazil, choosing to observe one of the five pillars of their faith might jeopardize their performance in the cutthroat final hours.

The last time Ramadan coincided with a major sporting event was the 2012 London Olympics. A study conducted on athlete performance and fasting reported that fasting had the greatest effect on individual athletes who competed in high-strain events, with a relatively small impact overall. As soccer is a team sport whose results can be impacted by a multitude of variables, the impact of athlete fasting in this tournament remains to be seen.    

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