The Australian MMA community is mourning the tragic death of 21-year-old Jake Sendler, who passed away from complications related to rhabdomyolysis — a rare and potentially fatal muscle condition linked to overtraining.

Sendler was hospitalized after competing at an event in Melbourne on March 3.
Despite being placed in an induced coma and undergoing multiple surgeries and blood transfusions, Sendler passed away just days later.

Doctors determined that the cause was rhabdomyolysis, a condition that occurs when muscle tissue breaks down and releases proteins and toxins into the bloodstream, potentially leading to kidney failure.

According to an industry insider speaking to News Corp, Sendler had been attempting to shed a dangerous amount of weight before his fight:

He told people he trained with on the Friday before the fight, approximately 48 hours before stepping into the ring, that he still had five to six kilos to drop.
Given that he typically weighs around 75kg, that means he was attempting to lose nearly 7% of his total body weight in two days.

Even in the midst of his health issues, Sendler still managed to compete through all three rounds of what would become his MMA debut, according to the GoFundMe page:

With profound sadness, we share the heartbreaking news that Jake has passed away.
Jake was not only a fighter in the MMA ring but also a true warrior in life.

While preparing for an upcoming fight, Jake unknowingly pushed through worsening symptoms [of rhabdomyolysis].
He continued training, working, and coaching, unaware that his body was shutting down.

Astonishingly, even as his organs were failing, Jake stepped into the ring one final time and fought courageously, demonstrating incredible determination and strength.

His mother, Sharone, shared a heartfelt warning to other young athletes:

Jake was an absolute warrior, such a good man.
He would never want this to happen to anyone.

Our message is to listen to your bodies, but keep being great and follow your dreams.

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