Running a marathon is an ideal way to get fit While running a marathon can be a good goal to set if you’re looking to get active, the truth is that long-distance running is not the healthiest ways to get fit. Unless, you’re looking to go pro it can put a lot of strain physically as well as mentally.   Instead, a brisk run for 10-20 minutes in your park can give the same benefit that you were looking for, as interval training is more effective for weight loss. It can make you active, boost metabolism and enhance weight loss, and make you fitter without straining your body. 