I completely agree that as women there's are fitness messages drilled into us that just seem like second nature. So much of that stuff is BS though. Eating a high carb, low fat, low calorie diet and doing a lot of cardio did nothing for me other than leave me feeling really tired and unhappy with my body.
As someone who's had serious issues with food for a looong time, I always payed attention to calories and fat. I pretty much was always hungry and when I ate it was a lot of carbs. I fed off my lean mass and pushed up my body fat with carb/sugar. As a result I ended up a bitty little "fat" girl. Eating clean really is a lifestyle change more than a "diet". I don't really think it takes much longer than a couple of weeks to get used to it-- and now I eat like a horse. My bf commented over the weekend that it seems like I'm always eating. It's awesome. I have so much more energy and I am surprised daily that I can eat SO much more (and better) than I used to without increasing body fat. I don't have to deprive myself to have the body I want-- that almost goes against everything I grew up thinking about fitness.
I like to do maybe 5-10 minutes of light cardio (usually bike) before I work out. It warms me up a little. I do 20 minutes of cardio after I lift too. I used to workout like your girlfriend does and I was never happy with how I looked. I have to say that now that I'm on a weekly split, I'm much happier with how my body feels and I give it adequate time to rest and heal before I work specific muscle groups again. There are a lot of splits she can try. I lift 3 days a week (chest/shoulder, back/bi/tri, legs) with a cardio day (usually swimming for an 45-60 minutes twice a week and doing a 30 minute high intensity running interval the other day) in between. For me, this is just right but I think everyone is different and should do what's best for them. I am also a big fan of lifting heavy. I really like to feel my workout for a day or two afterwards and I don't feel like I've done anything if I haven't pushed myself. Try to drill it into her head that really working her muscles with lower reps and higher weight will not make her bulky-- it'll just make her more firm and she'll likely be happier with how her clothes fit.
Like everyone said though, diet is key. My little sister is a college athlete. She works out like a mad woman-- more than I could ever handle-- and her body fat sucks because she eats a really high carb crappy diet. If she ate clean, she'd be SO amazing.
Encourage her to set goals. Has she had her bf taken?? That might help. My goal right now is to drop bf while building/maintaining lean mass. It's a much better goal than my old "I want to drop 10 pounds". I'd do so by depriving my body and losing muscle. I was never happy with it. Now I realize that I can put on muscle weight, drop size, and generally be more content with what I see in the mirror. In the past month or so my entire concept of weight has changed. Yet another thing that does contrary to those ingrained women's fitness myths-- it is definately possible for me to be a little size 4 fat-ass.
Hope you figure out something that works well for her that she'll also enjoy.
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