As the buzzer went off, Mat fell to the ground before the medical team rushed to his side.
“My body just shut down on me and I struggled to breathe,” the Channel 7 reality star explained.
“I got really hot and this horrible nauseous feeling came over me and I started to panic.”
Mat was later rushed to hospital with brother Tim by his side.
The 27-year-old later revealed to New Idea the circumstances leading up to his collapse.
“It got a bit full on and it was a really hot week, especially that day. It might have been 32 or 33 degrees that day. And there was a big dust storm that came through as well.
“We pushed and pushed and pushed and probably let my health get away from me a little bit and you know, I skipped lunch and didn't stay hydrated,” he admitted.