I don't know if this strictly counts as a "Game Show" but I proper loved Don't Try This at Home on ITV on a Saturday teatime as a kid.
Davina McCall, Kate Thornton and Paul Hendy challenging ordinary people to face their fears and have them doing crazy, terrifying things, basically bushtucker trials before the birth of I'm a Celeb.
Be anything from something small like interacting with spiders/snakes to massive challenges like bungee jumping from helicopters, abseiling big skyscrapers, etc in exotic locations sometimes too.
If the "contestant" chickened out then Davina would have to do them instead iirc.