A report in Sport in July claimed Hazard was seven kilograms too heavy when he joined up with the Madrid squad for pre-season duty.
The Belgium star has found it difficult to kick-start his career in LaLiga since joining from Chelsea in the transfer window, only scoring his first goal for the club in last weekend's 4-2 defeat of Granada.
Martinez, though, does not believe Hazard's physical condition is a particular concern given the talent he has.
"He is a really calm person, not someone who looks for individual glory," he told Deportes Cuatro."Whether he's carrying weight or not, Hazard can break past and unsettle defences and make a difference.
"His innate talent doesn't depend on whether his weight is this or that."