You might be asking the right question...but you might not.

What is your goal in poker? And does playing longer sessions get you closer to that goal?

What are your goals in life, and does playing longer poker sessions get you closer to them?

I ask cuz you said, "double the roll" and "have fun at poker", but those two are sometimes incompatible, and sometimes rec poker players (me, you, most of us here) don't fully understand what we want, never mind how to get it.

Doubling the roll, is (to some extent) a math question: win rate, hours, study/review, get on the good side of variance, profit. Easy peasy to calculate. Have fun at poker while still making some profit (ain't no fun to lose) is a whole different can of worms. For many of us, long sessions aren't much fun, and if we have FT jobs and a life outside of work and poker, well, there might not be enough hours in the day.

If poker is a hobby, then treat it as such. You can be serious about your study and practice proper BRM without pressuring yourself to play more. It's not your full-time job! Unless you want it to be, in which case the question becomes about how much you are willing to sacrifice to achieve your poker goals. Are you willing to give up poker being as much fun? One less evening a week with the mates or girlfriend? Skip the gym or quit the soccer team?

As you have figured out by now, I don't have the answer for you. But it's food for thought (assuming you like my cooking).

This for me back in the day when I was young and coming up was never an issue. I put in sooooooo many 12-36 hour sessions both live and online. I guess I was just more hungry and hooked on the game back then.

Now I barely put in long sessions and if I honestly played more than 4 hours in a day I would be surprised.

So my answer honestly is - you should just want to play that session then it is easy to do.

This is pretty good question. I start to lose my focus after one hour, and then I have to have a break before my perfomance level begins to drop. For me 4-5 hours in one day is enough.

It's all about building up to a sustainable amount of volume. Most people will find that they can put in a monster session over a day or two, but then they're totally burnt out and can't play at all for a couple of days.

I learnt this lesson the hard way when I changed from reg tables to Zoom and was doing a minimum of 1500 hands/hr, burn out arrived pretty quickly and wasn't something I'd ever experienced before.

The easy advice is to maintain a regular schedule and make increases to your volume every week or two. Physical fitness will also play an important part in how fast you can recover.

In terms of fun, if it becomes a literal "grind" then it's too long