I've had the best success losing weight and keeping it off by joining Curves gym. They seem to be everywhere here in Canada and I know they are in the UK as well. You can get travel passes for other clubs when you travel so you can keep up your workouts. It's women only, takes only 30+ mins, and they also have a diet component if you want to use it. I don't, I just keep track of what I eat each day and try to keep between 1400 and 1700 calories a day. They encourage you to weigh in and get measured once a month - since January I've lost 30 pounds and kept it off! I've tried lots of other ways to lose weight over my 62 years, but this is the best! And we leave for an Alaska cruise on Saturday, so I'll just have to walk the promenade deck and climb the stairs to keep up my exercising!