After finishing his ward rounds, Chen Yu arrived at the rehabilitation center to find Ronaldo running on a treadmill, wearing an oxygen deprivation mask.
Chen Yu frowned immediately. He grabbed a trainer and asked who had authorized Ronaldo to train like this.
"He did it himself," the trainer said, looking aggrieved. "We already told him it was useless, but he didn't believe us. He insists this kind of training will boost his endurance. We tried to persuade him, but it was no use. And since you weren't in Phoenix, he flat out refused to listen to us."
Chen Yu sighed.
Simulated hypoxic training, or altitude training, did indeed have its benefits. In a low-oxygen environment, the human body was forced to produce more hemoglobin, increasing the blood's oxygen-carrying capacity and thus boosting endurance. This was especially true for long-distance running. It was part of the reason why distance runners from the high-altitude regions of Africa dominated the track and field world.
