Run daily, get plenty of rest, do not smoke, drink alcohol moderately and eat a vegetable-based healthy diet.
Unfortunately, Stonophi, I smoke tobacco, drink alcohol in the evenings, and eat microwave meals. ☺ I do get plenty of rest though. ☺
The best way to keep fit is to do something that you like to do and yes, you have to keep doing it. That's why it should be something that you like. If you have a lot of "bad" habits, there is only so "fit" that you will get. There is no free lunch. There is no getting healthy while smoking cigarettes.
I mix up the exercise but ive mostly given up disc golf... i keep throwin it hard an makin my arm sore... but i like walkin outside an average a 17 minute mile... an when the weather is bad i use a arm/leg powered exercise bike... an my replacement for disc golf is ping pong... average 2 houres a day.!!!
I'll stick with my 7 miles a day seven days a week mornings after my 20 Taekwondo patterns, throw in a little weight training and 1 hour afternoon backyard soccer with my Lovely Lady Labrador. That on top of a healthy diet, some Zen meditation and plenty of sleep. Now, if it wasn't for that little bit of stray acinar adenocarcinoma I would be pretty healthy for 68.