Lately I am trying a new adventure, a triathlon. The requirements of the event I am attempting is a 500 meter swim, a 10 mile bike, and a 3 mile run.
Of the three events the run is the most difficult for me and I have been training for it since January. My plan started with a 10 minute run, not very long and certainly not that far but all that I was capable at the time. Each time I went out for a run, three times a week, I added one minute to my outward bound time two minutes overall. If I fail at a time goal, and I have, I do it again until successes is reached.
The point of this is that even though my gain each run is small I have been able to reach almost an hour of running. The same principle can be used for biking, hiking, climbing, kayaking, etc... all that is required is a little disciple and a goal to reach for.