I don’t know anything about running a marathon. The physical one. I have never run it. To be able to do so, I’d need to train, at the very minimum for a few weeks. I’m going to struggle to run for 5 miles even. I’ll probably do it, but I may not enjoy it or consider ever doing it again.
I have however run a mental marathon. I trained for it and I enjoyed it. Although it was tiring like the physical one, I thoroughly enjoyed running it and kept going back to run it.
When you have large goals or you’re trying to build something complex, it won’t happen easily. It might be as easy as running in a straight line, but you would probably need to run for a long time and you will need to build endurance. Once you have built endurance you can probably do it over and over again. You would also enjoy every time you would run this marathon. However, if you don’t run a mental marathon for a really long time such as taking time off and putting the brain at ease, you will need to train again, just like the physical one.
Your IQ wouldn’t have changed during this time. You would still be mentally as capable as you were before, but you wouldn’t have the endurance to run a mental marathon. On the bright side though, for a former marathon runner, it’s easier to build endurance again. Easier than someone who hasn’t done it before.
If you feel you’ve big goals and the aptitude or the IQ but are somehow still helpless and incapable of getting to them, it’s the endurance issue. You get on the mental treadmill, but you’re too irregular. You build the endurance a little bit, and then you go back to your old ways. You fail to build on your previous progress. If you can do that, you’ll see yourself on the other side.