Courtney Lawes admits both of his shoulders were ‘pretty knackered’ last season.
But the Saints and England star says he will be back on full throttle for the Rugby World Cup, which begins on September 18.
Lawes was rested by his club towards the end of the previous campaign, having been forced off at half-time in the Champions Cup defeat at Clermont Auvergne in April.
But he is now in training with England, who have flown to Colorado for a training camp, with the World Cup on the horizon.
Stuart Lancaster’s men begin their bid against Fiji and Twickenham, with Wales and Australia also in a tricky pool.
Lawes will be key to England’s chances and the lofty lock is adamant he will be at his physical peak for the tournament.
“Both shoulders were pretty knackered (last season), and I was struggling quite a bit to tackle effectively in games,” Lawes told BBC Sport.
“But now I’ve got a chance to really get my shoulders good, for the biggest tournament probably of my life.”
And he added: “At the end of last season I was in a pretty bad place. That was a bit disappointing to be honest, but I would rather have played and done what I did than not played at all.
“It was a long season and if you hurt your shoulders it’s really hard to recover.
“So I will go in [to the World Cup] hopefully with fresh shoulders, strong, and I will be all right.”
Lawes has the talent to be one of the stars of the tournament.
And he said: “I think I’ve got the potential. As long as I’m fit I can play as well as anyone I think.
“I just want to play to my potential, for the team, for the country, and hopefully do everyone proud.”