Hi - I only manage to get a run in 2 or 3 times a week, but I prefer to run outside. I don't have a treadmill at home, so I use the one at the gym if it's too cold, or hot, or rainy, or otherwise not nice. The problem is there's a 20 minute time limit so if someone else is waiting I have to get off and do something else. My runs still consist of running/walking, so they tend to take up a lot of time (1 hr for a total of running 3 miles, walking 2). I guess it's a matter of what you like best, how convenient it is for you, and how good you feel when you're done. Whatever works for ya!