If you plan on not eating or drinking liquid afterward... Yes. Body fat is a factor, but most of the lost weight would be water weight that's gained back through food and liquid. It's the reason Pacquiao has to eat so much, he has to gain the weight he's lost in training back.
Try running for an hour or an hour and a half. Weigh yourself before and after, see how much you lose. Then go to the boxing gym, put in however many rounds of the exercises these fighters are putting in (3-8 rounds of shadow boxing, jumping rope, punching bag, double end bag, speed bag, ab work) and see how much in total you lost during the day. That's a normal training camp day.
Try running for an hour or an hour and a half. Weigh yourself before and after, see how much you lose. Then go to the boxing gym, put in however many rounds of the exercises these fighters are putting in (3-8 rounds of shadow boxing, jumping rope, punching bag, double end bag, speed bag, ab work) and see how much in total you lost during the day. That's a normal training camp day.
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