But it 's a different thing for the age - grouper sort who wants to run forever .
It 's different if you 're a professional runner who is out to make a killing and be finished with running by the age of 25 .
It 's a different thing for the age - grouper sort who wants to run forever .
It 's different if you 're a professional runner who is out to make a killing and be finished with running by the age of 25 .