I lost about 60 lbs 7 yrs ago and have kept most of it off. For me, after 40 the weight started piling on. I started by walking, lots of hills, long distances and modified my diet to a less processed, fewer grains/starches, less alcohol, more veggies and fruits type. Lost weight, but didn't get the results I wanted until I added reisistance (weight) training. Started with a conventional program using typical machines at the gym, then moved into a Crossfit program about 2 years ago. Crossfit stresses functional fitness using your own body weight, kettlebells, Olympic lifting plus cardio and balance. It's a work at your own pace, accomodations made for those with problems, supportive community. The WOD (Workout Of the Day) mixes things up so it stays interesting and I've been happy. Plenty of material online about the philosophy behind Crossfit. Practically, on dive boat recently with 2 thin girls neither of whom could carry a tank, while I've got one in each hand and I'm twice their age. They were thin, but not fit. I'll take fit and healthy but a bit heavier everyday.