At 6 miles an hour, that's 5 hours a week of running? An awful lot of people couldn't fit that in
Most people could; they just choose not to. I work full time, am doing a postgrad, and have two small DC. I also can't exercise in the evenings, as I have sole charge of the kids, which leaves me less time to play with.
Don't mean to sound like Smuggy McSmugFace, but I choose to make it work, and would rather run than watch tv/sit on the sofa/whatever.
So how it works for me is:
One long run on a Sunday, before the kids are up, of 2hrs ish
Parkrun with warm up and down on a Saturday (say, for arguments sake, up to an hour)
And then 2/3 runs midweek, of 4/5 miles each. These are either in lunchtimes or as part of my commute.
I cycle to work if I'm not running, which helps keep up the activity levels, too. I also swim one day a week, and try to get to the gym on the other day I don't run - though that often falls by the wayside if I have life admin piling up. I can't imagine the cycling helps the cellulite much though, as it's only 30 mins-ish and I'm carrying a lot of stuff, so not exactly pushing it hard.
5 hours of running may sound a lot (though it's not really 5 hours, as it's a lot faster than 6 miles per hour IYSWIM), but even 5 hours a week is do-able, even for busy people. You just have to want to prioritise it, and I get that most people don't! It's not easy to get up at 5am on a cold dark Sunday, but it's important to me, so I do it. Anyway, very sorry to derail the thread again...but it does sort out cellulite!