I've run 25-28 miles a week for the last 8 years. This fall I've transitioned that partly over to using an Elliptical vigorously for 45-50 minutes per day. Partly because I'm tired of running through Idaho winters, partly as a change of pace and partly because I'm a little concerned about the toll my joints have taken over that many miles of pounding. My wife exercises daily as well. Also as a family we try to have active hobbies such as skiing, hiking, biking, etc. We are in our late 30s. The benefits of being fit far outweigh the effort it takes to maintain it, or at least that's been our experience thus far.
With regard to the comment above about cutting fat from the diet, that's too simplistic. Whole fat dairy is healthier than reduced fat dairy for all ages, and there are many healthy fats that are an essential part of a good diet. I'm not advocating a bacon sandwich for lunch every day, but the standard healthy diet script we've been fed the last 30 years is pure nonsense funded by big industry.