I have heard from multiple sources that when you are winning a poker game it is prudent to keep playing that game rather than lock up the win and leave.

I want to ask this forum if this is sound strategy or not? In YOUR experience should hero keep playing? I understand the logic, but oftentimes when i win at a game i loose the money back and wish i had walked away, but that logic of playing more when you are up kept me in the game. There have certainly been times where this thinking booked me a huge win.

This isn't really a poker theory question, it's a psychology question, or maybe just a practical issue regarding your own personal strengths or weaknesses.

If you play worse when you're up, then you should leave
If you play worse with a big stack, then you should leave
and so forth.

Maybe so i thought theory was the most appropriate subforum because this is not really about psychology its about risk-reward. I am just including my experience as an aside. This is a very common piece of strategy that i have heard many times, the reason I posted this in the theory forum is because it is a theory question.

Should hero risk his winnings because there is possibility of a much larger win? Is this rule dependent on the game (super agro players=more risk etc). Psychology is involved in this question but I thought it more of a theory question.

This piece of strategy (that hero should continue a winning session) is widespread, does YOUR experience confirm that this is the right way to play? Maybe this does belong in a strategy subforum, this is my ninth post on 2+2 so Im not really sure. Maybe someone can give me a constructive response.

It's not about risk/reward, though. What's the difference between "risking" the money you made today and risking the money you made yesterday. If you leave up today and come back tomorrow, you're still "up" the same amount and you have the same amount to lose.

Having a larger stack may or may not effect hand strategy. If you have 200bb and everyone else has 100, then you effectively have 100bb and all strategy remains the same. If some other play have 200bb then strategy changes.

If you were playing blackjack for $10/hand and won a bunch of money, but kept playing for $10/hand, then there is no more risk to stay and play than to leave and come back tomorrow. If you start playing for $20/hand because you have more money, then your risk is increased. In poker you don't always get to decide how much money will go into the pot, so if you have a big stack and some other people do to, then your risk can be increased somewhat.

It's not a piece of strategy, it's just folk wisdom. A better piece of advice would be to keep playing if you can keep making money and leave if you can't. There are many reasons why being up a lot, or having a large stack might reduce your changes to win money, but those again are going to be personal reasons, not anything intrinsic to having won money.

I recommend you read, or listen to on audiobook, Tommy Angelo's book "The Eightfold Path to Poker Enlightenment"

Keep playing if you've got a skill edge on your opponents. Bank the money if you don't have an edge and you just got lucky.
FWIW, I usually quit if I have a big stack, because I'm not great at playing deep. My skill edge is maximised at either 50bb or 100bb deep, as those are the stack sizes I've studied/played the most. I also like to bank a win if I'm playing on a short bankroll (e.g. if I've only got a small amount of money on one site. I don't want too much of my 'roll' being at risk on one table, so banking the money is kind of a variance-reduction strategy.)

In addition to the most important factor noted by Arty, which is the stack size you have studied most off-table, I will add the psychology side of the question.

Banking a large stack and sitting down at a fresh table with 100 BB is a perk of online poker and helps reduce variance to your bankroll. Assuming there are plenty of tables available of course.

This is just for psychology purpose. You get to “feel good” about adding 3 BI to the roll.

Personally, I will move tables at about 250 BB, with potential exploit play up to a max number of 400 BB. No matter how juicy the table, there is always another good table at the micros.