The bread test
Djokovic reportedly switched to a gluten-free diet after failing a strength test while holding a piece of bread.
Yes, you did just read that right.
In 2010, Djokovic met with Dr. Igor Cetojevic, a Bosnian Serb, who believed Djokovic’s frequent physical breakdowns in matches was due to a wheat allergy.
Cetojevic told Djokovic to put one hand against his stomach while holding the other straight out with his palm up. Cetojevic pushed down on this hand and told Djokovic to resist the pressure, which he did easily.
Cetojevic then told Djokovic to do the same thing while holding a piece of bread against his stomach. This time, Cetojevic said he easily pushed Djokovic’s hand down.
“He was clearly weaker,” Cetojevic said. “It showed that his body was resisting the wheat.”