O'Connell signed a contract extension until June 2016 in January and hopes to represent Ireland at the 2015 World Cup, provided his body holds up.
And the Ireland captain is also forging new relationships with former team-mates and friends Anthony Foley and Jerry Flannery, now his head coach and scrum coach respectively.
"When I look back on the years that I played my best rugby - 2005, 2006, 2008, the year of the World Cup - they were all down to big pre-seasons," said O'Connell.
"The second-row is such a work rate position - you are trying to accumulate tackles, ball carries, rucks and you need to have that big work load done in the summer.
"I'd love to go to the next World Cup but I'd like to go there in really good shape as well.
"It's certainly been strange to be coached by Jerry. I'm trying to keep a straight face because he's a different person when he's coaching. He's meticulous in his preparation and everyone knows that.
"I'm experienced enough to know that that's the way it has to be and he is as well."