I've been doing about 1600 lifts (pushing the up and down buttons on the keyboard repeatedly) in the exercise room and I still haven't finished this blasted mini-game. This mini game determines your PCs speed and you have to do as many push-ups as the speed of your PC is. I've heard it was only 25 back in the days, but now... gah!

Is there any way to fix this?

This is a case where using dosbox would probably improve things. You can change the cycles.

I don't know if ScummVM (which GOG installations are installed in) allows one to change the system speed.

In any case it would be best to play most of the dos games except perhaps the AGI version of LSL1 in dosbox they run more efficiently on dosbox, and you can change the game speed for problems like this.

You can learn more here;
http://www.sierrahelp.com/Games/LeisureSuitLarry/LSL3Help.html

Thank you, I managed to fix it through the link you sent.

I played through it the other day in ScummVM and I only needed 12 reps for each one.

Yes, scummvm is explicitly suppose to fix this bug so I'm surprised it's broken for you.

Different, or older versions of ScummVM?

I just checked the ScummVM source code history, and LSL3 has had throttling applied since January 2010, so I don't think this is the issue.