if you let it in it will want to be in all the time.It will need to learn that its outside when no ones there. we let ours in to. if you have a utility or that and you dont mind it lying in it when your there.
Theres deff dogs that will do 20 miles, but its not good for them in the long run, its very sore on everything, heart ,lung ,joints. i actually ice my girls legs after a day were i feel im wrecked after a ride. few rests and if she finds a river she drinks and bathes in it a bit. i have to slow my pace and times to, they try to keep with you and dont understand that they could fall back some, but are afraid to let you out of sight.