By fuelling himself to take down feared middleweight king Gennady Golovkin, Kell Brook believes he has become the perfect family man.
The 30-year-old unbeaten IBF welterweight champion will step up two weight divisions and face arguably the most daunting assignment in boxing when he squares off against Kazakh phenomenon Golovkin at London's O2 Arena on September 10.
Golovkin has won all 35 of his professional bouts, stopping 32 opponents on his way to collecting the WBA, WBC and IBF titles.
But, speaking in his native Sheffield as his day of destiny looms closer, Brook cut a relaxed figure - something he credits to not having to boil his muscled frame down to the 147-pound welterweight limit.
Partner Lindsey and their two young children have also been reaping the benefits.
"It's fantastic. I'm a nicer guy," Brook said. "If my missus was here, she'd tell you how nice it's been at home.
"I'm able to eat and she's super happy with me. There's no more Mr Grouchy, I'm happy because I can eat.
"I've been getting plenty of sleep because I've got a belly full of food. It's been great.
"I've got loads of energy and I'm playing with the kids. It's those little things and I don't get ratty like I am when I'm making those lighter weights."
Brook also feels the extra weight has helped him hit new heights in the gym, with Liverpool's WBO light-middleweight champion Liam Smith among the sparring partners.
Smith fights Saul 'Canelo' Alvarez in Arlington, Texas, on September 17 in his own against-the-odds tilt at one of the sport's pound-for-pound superstars.
"It's been nice having that extra weight and just getting used to the bigger size of the guys," Brook explained.
"I've been keeping my speed, developing more power too. I'm light on my feet, but also able to dig down and pull out some big power shots. I feel sharper at this weight."
***Sky Sports Box Office will show Golovkin v Brook on September 10. Order now at skysports.com/golovkinbrook***