Just use the principle of progression, slowly increasing duration and resistance. But the key is to not run too much. Incorporate a variety of cardiovascular exercises so that you can push your cardiovascular abilities without overworking specifuc mechanics.
For example if you just start running every day more and more sure your heart, lungs and muscles will become more efficient with their work. But you run the risk of overworking your knees, getting shin splints ect. So rather do 20 minutes of walking, 20 minutes of biking, 20 minutes of plyometrics. The next day change your emphasis to more running. Then the next day don't run at all but meet your training requirements through other means.
Principles of periodicity and progression.
Once you ensure to have a level of fitness, proper mobility and you are stronger at that point you can specialize on your running.
All that being said Imho it's not a good idea to run and only run, especially as we age. Our bodies become less tolerant to repetitive activities. The key to a good running program is variety
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Thanks! I will definitely keep that in mind.