Training

How to prepare for hiking 15 to 20 miles per day 3 to 7 days in a row at a time? I don't run (back/neck issues) so the only way in my mind to get in decent shape is to hike when time allows. Fortunately we have within a 10 minute drive of our house one of the coolest city wilderness parks in the world; 5,200 acres of Portland's Forest Park. There are several miles of trails in the park with the longest called Wildwood at 30 miles. Lots of loops if you mix and match the trails that cross each other. My plan is to hike 20 to 40 miles a week and hopefully be in good enough shape by July to stay with the youngsters and not be in too much pain the first few days. That's all I can hope for!