Absolutely! Let me start by saying that I power lifted for years, but outside of that I was not very disciplined. A couple years ago I came across Jocko Willinks twitter which led me to his podcast. His no nonsense "Extreme Ownership" approach spoke to me. If you want an introduction to him, a good start would be to listen to him on Tim Ferris or Joe Rogans podcast first. His YouTube channel also has a lot of clips. My summary of take aways are:
* Motivation is fleeting, so is something that cannot be relied upon.
* Practice discipline every single day. I have found that discipline builds upon itself. I get up at the same time every day (even on the weekends). I work out every day. It's not even something I think about, it's just what has to be done.
* I get up early, not 4:30 early, but between 5-6am every day (and before all the sleep is required people jump on me, I'm in bed by 9-10pm). It sounds silly, but jumping out of bed ready to go when the alarm goes off is the first discipline win of the day.
It's really just a mindset of doing what you know needs to get done. Whether it's working on something at work or controlling your emotions when someone cuts you off in traffic. There are tons of opportunities every day to practice and help you improve your discipline.
If there was one book that I would pick to read, it would be Musashi. It's probably not the standard book someone would recommend, but it was huge inspiration for me. It is an amazing story with so many lessons on discipline and life.
Finally, not to get too philosophical but I also see many of the same lessons when training Jiu Jitsu. It teaches many things beyond discipline, and is something I recommend to everyone.