My favorite running wheel for my dwarf hamsters
is the comfort wheel by Super Pet. This wheel is quieter than
traditional metal wheels and very easy to clean since it is
solid plastic. It also has the additional benefit of not having
any rungs with spaces that might break a hamster's leg if he
or she misstepped. You can also use "exercise balls" as
they do come in a small size especially for dwarf hamsters.
If you use the exercise with or instead of a wheel, there are
a few guidelines you should follow.