Since the release of the Metal Gear Solid: Master Collection Vol. 1 , modern trainers have been developed to work with the updated executable.
This is often safer than PC trainers.
The infamous button-mashing torture scene (where Otacon’s sister, Sniper Wolf, watches) is a known hand-cramper. A "full" trainer typically offers an "Auto-Complete Torture" or "Infinite Continue" option. metal gear solid 1 trainer full