How Ramadan Fasting Could Affect World Cup Players

iStock/Thinkstock(NEW YORK) — Tuesday’s World Cup match between the U.S. and Belgium could be particularly grueling for players who are fasting from dawn until dusk for the holy month of Ramadan.

There a four Muslim players on the Belgian team. And while starter Marouane Fellaini has said he’s not fasting during the tournament, it’s unclear whether his three Muslim teammates will be playing the afternoon game after eight hours with no food or water.

Asma Aloui, a researcher in exercise physiology with the National Center of Medicine and Science in Sport at the Tunisian Research Laboratory, said there are six ways fasting could influence their game:

It Can Impact Sleep

Studies on fasting and sleeping during Ramadan are rare, but Aloui’s research suggests eating only after sundown may cause players to toss and turn in bed by disrupting their internal clocks. Although the study didn’t make any conclusions about the effect of these sleep changes on sports performance, it did demonstrate that during the holy month, players went to bed later and slept less overall. Naps would help make up any sleep deficits, Aloui said.

It Can Slow Thinking

Aloui’s group found that people who fast during Ramadan experience less anxiety and depression. However, the same study found that fasting slows cognitive ability, which means players might have some trouble thinking quickly on their feet. Brain fog tends to increase towards the late afternoon, Aloui’s studies found, which does not bode well for the Belgian players on Tuesday.

It Can Cause Dehydration

Aloui’s research suggests that Brazil’s blazing heat may be a problem for players who aren’t able to guzzle water to replace fluids lost from sweat. Parched players are at increased risk of muscle cramps, heat exhaustion and heat stroke. Sweating off just 2 percent of your body weight leads to decreased blood volume, rapid heart rate and difficulty regulating body temperature, Aloui has found. It can also cause an electrolyte imbalance, further impairing performance.

It Can Affect Overall Performance

The combination of hunger and dehydration could affect multiple aspects of a player’s game, Aloui said. Her research has found that some players experienced diminished hand-eye coordination, quicker muscle fatigue and reduced power, speed and agility under the strain of fasting.

Timing Matters

When Ramadan occurs during the summer, it presents a real challenge for players who might be fasting for as long as 18 hours, Aloui said. And the effects of fasting accumulate over the course of the day, so players slotted for evening games could have it tougher than those who play first thing in the morning, she said.

Gradual Adjustment Is Best

The longer a player remains in the tournament, the more his body will adapt, Aloui said. One study of 85 professional Tanzanian soccer players showed that over the course of the month, athletic performance gradually improved to pre-Ramadan levels for athletes who continued training at high levels.

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