Or even just begin all around good design. You can invest in dumbbells, barbells, workout benches, exercise balls, steps, resistance bands, exercise mats, ab trainers and even more.
The latest treadmill trainers have built in shock absorption to help ease the load on your joints. https://dobetterhub.com/doku.php?id=bowflex_exe_cise_-_it_should_help_you_lose_weight