The most crucial factors for an extended life , I do believe, are partially in the genes; number 2 is lifestyle, which include healthy diet and standard exercise. I walk, run and move every day. But, I believe an excessive amount of workout can also be detrimental because of over-stress; sometimes people who workout also many hours daily die early.
The nice point about’Arrow’is we never state never on the show. Preferably the show could have a good extended life , and all manner of points could happen.