David Hasselhoff sucked in his gut on 'Baywatch' because he wanted to look his best when in his skimpy swimwear.The actor - who played head lifeguard Mitch Buchannon in the classic series - says the cast, who were required to wear skimpy red outfits, would often breathe in when the cameras started rolling in order to look good.He said: "Well, we had a thing on 'Baywatch' called the 'rolling six pack'. What that would mean is we all come to work and then we'd say, 'Roll cameras', we'd suck it in and we'd do the scene. And then they'd say, 'Cut', and then we'd let it out."If you watch 'Baywatch', one key to 'Baywatch' was in the beginning of the year you would see beautiful slender bodies and the shot would be all of us, entire body. By the end of the year, the camera would move slowly up so soon the only thing at the end of the show was [our heads] because the rest of your body really turned into a mush."The 63-year-old star also explained how he dealt with shrinkage around his genital region when he would film scenes in the water for the show, revealing he wouldn't come out of the water until everyone had gone home.He quipped to Australia's 'The Morning Show': "When you go in the water, do not come out. Do not come out until everyone has gone home. And there's a route... when you come out of the water, walk out backwards."