Claressa Shields has reinvented herself in her attempts to achieve light heavyweight and heavyweight glory.

The undisputed middleweight champion, widely recognised as the finest female fighter of all time, on Saturday fights at 175lbs for the first time when she attempts to dethrone Vanessa Lepage-Joanisse as the WBC heavyweight champion and to win the vacant WBO light-heavyweight title.

Shields has previously also reigned as the undisputed junior-middleweight champion, and largely because of her cultured edge and fast hands. On Saturday at Detroit’s Little Caesars Arena, however, she inevitably fights a naturally bigger opponent, and instead of relying on those same traits to inspire her to victory, she has promised a more thoughtful and explosive display.

The additional weight means that the 29 year old has had to dedicate considerably less time to cutting down. She therefore has placed an increased emphasis on her tactics for her Canadian opponent, and believes that her additional size and energy in training sessions have given her heavier hands.

“I can concentrate on the actual game plan for the fight, and not running so much,” she told BoxingScene. “Running – you’re having to lose 30lbs. Sometimes you gotta run five times a week; four times a week, and that can be stressful on your body, because you can’t put boxing first. You gotta put losing the weight first. Which is the running; the strength and conditioning; help you lose the weight. I’m still running, but I don’t have to run as much. Usually, when I’m in camp, I’m running specifically to lose weight [and this time it’s for my conditioning].

“You’re gonna see me be more calmer, because I have the energy to do so, and I have the punching power to do so. It won’t be as many punches, but the punches will count, and the punches will be effective. That’s what you will see. You will see that if she wants to force me to fight inside the pocket – she wanna come and brawl – you’re gonna see that I’m gonna win that. 

“I’m gonna win the mid-range exchange; I’m gonna win the long-range exchange, and you’re gonna see who’s the true heavyweight in the fight; who has true punching power. I’m hoping she’s prepared for this fight, and comes with the confidence that she came to the press conference with – getting in my face and saying I’m too little. I hope she has that same energy when she gets inside the ring, because I’m gonna punch her lights out.

“I don’t have to lose a whole bunch of weight. I keep eating everything – I [still] force myself to eat healthy – and I’m pretty lean, but I have added on some muscle, and you’re gonna see that muscle during the weigh-in and during the fight. You’ll be able to see my punches – it will linger on my opponent. I’ve added the needed muscle in the places I need it; sparring went completely well, and I’m hitting a lot harder and getting respect from my sparring partners, who are 180lbs; 190lbs. The whole thing of me not being able to punch is a myth – I could punch really hard, and now I’m putting on the right muscle and eating the right food I’m gonna be very strong.”

Regardless of the identity of opponent – Lepage-Joanisse is also 29 – making so significant a move up in weight can be fraught with risk. Some of the most respected professionals – Mikey Garcia when he moved from lightweight to welterweight to challenge Errol Spence in 2019 is a high-profile recent example – appear sluggish when they do so, partly through having gained fat instead of remaining lean. 

Other professionals can tell tales of the amount of food they have had to eat to minimise the risk of their bodies attempting to return to their natural weight division, but though Shields will only know for certain the extent of her success come fight night, she is convinced that Lepage-Joanisse will be able to see the difference when on Friday they weigh in.

“I’m not sluggish at all,” she said. “If I’ve been sluggish it’s because I’ve been tired from working so God damn hard. My punches are coming off straight and strong; when I land punches, it’s effective punches. I can see them [sparring partners] getting on the back foot. That’s the difference. In fights I’ve hit girls and they’ve jumped on their wheels but now I’m able to hit them, cut off the ring, and hit them with other hard punches. I can tell that there’s power and there’s weight behind my punches, and that’s getting the respect of a lot of the people I’ve been working with. 

“I’m eating a little bit more. But I can never get tired of seeing food. I’ve had to lose, sometimes, 30 and 40lbs to make 160lbs, so I’m never going to get tired of seeing food. Here in Atlanta it’s so much good food; soul food. I’ve been eating a lot of pho; a lot of mediterranean food. I’ve still been eating my grilled chicken; my grilled fish; rice. I could eat more rice than what I was able to eat when I was in camp; I was able to eat bread this camp. I can maybe double my portions. But I haven’t just indulged like the body builders have. I’m not overeating, because I’d have a fat belly, and I wanna have a six pack at 175lbs.

“I have a lot more energy. I’m in Atlanta, and it’s so hot – sometimes the heat is a bit much to deal with. But I’ve been doing a lot of recovery; I’m sweating a lot, I’m working hard, and I do have a lot of energy. The gym’s 80, 90 degrees. Sparring was good – I got everything out of it that I wanted to get out of it. I know [on one occasion] why I wasn’t as sharp as I wanted to be so I made sure that I fixed those things so when I go into the fight I’m sharp; strong; fast.”