I suspected the author was Cory Doctorow (just a feeling), so I started looking for the story. I'm pretty sure its 0wnzored, located here. The story involves a guy who learns to overclock his body and metabolism, giving him immunity to cancer and disease and all around physical perfection. He ends up escaping from the facility that was experimenting on him, which matches your memories.

I suspected the author was Cory Doctorow (just a feeling), so I started looking for the story. I'm pretty sure its "0wnzored", located here. The story involves a guy who learns to overclock his body and metabolism, giving him immunity to cancer and disease and all around physical perfection. He ends up escaping from the facility that was experimenting on him, which matches your memories.