Anthony Joshua says he is feeling more rested ahead of his world title unification showdown with Joseph Parker than he has for many of his other big fights.
Joshua, 28, will put his WBA and IBF world heavyweight titles on the line when he meets WBO champion Parker at Cardiff's Principality Stadium on March 31.
Although the New Zealand fighter represents the biggest challenge of Joshua's so-far undefeated career, the Brit claims to be emerging from his current 12-week camp with more energy than he has on previous occasions.
"I feel good. A happy fighter is a good fighter," Joshua told ESPN. "It's been a long time since I've been going through camp and wake up feeling like I've rested.
"It used to be groundhog day," added the former Olympic champion, who explained that he used to wake up in the early hours of morning. "It used to kill me."
By waking up a bit later every day, Joshua said that he began to see big improvements in both his mentality and his performances in training.
"We just pushed it back a little bit so I spent more time resting, which is as important as training," he added.
"When I am well-rested I have more concentration, more energy to give to the sport. So when they're asking me to do 15 rounds I'm begging to do 18 rounds.
"Before I would do 12 and I would be like 'man, I don't know if I have another three in me', so we just flipped that around."
Joshua will have to be on top form if is to beat his opponent in Cardiff. Parker, 26, is also yet to suffer defeat in his professional career and recently defended his WBO title by defeating Hughie Fury in a majority decision/
The winner of the meeting between AJ and Parker is expected to seek a fight with WBC titleholder Deontay Wilder for the chance to create history by unifying the heavyweight decision.