Dear Harry Hamster: Happy, my 6-month-old male hamster, doesn’t use his exercise wheel. The other hamsters I had over the years ran on their wheels. Is Happy just lazy?

Harry Responds: Most of us hamsters enjoy our wheels, although some don’t, just like some people don’t relish jogging on a treadmill.

One study of wheel preference found that hamsters like large wheels, the 35 cm (13.8 inch) diameter size rats usually use, more than the standard 23 cm (9.1 inch) hamster wheel. They also prefer a running surface with closely spaced metal bars, rather than bars covered with plastic mesh.

Another study investigated foot wounds from standard metal bars versus bars covered with plastic mesh. Almost all hamsters developed tiny pinpricks, cuts or scabs on the undersides of the feet, but the hamsters that used the mesh-covered wheels had larger and more persistent foot wounds than the hamsters that ran on wheels with metal bars.

Experiment with a larger wheel that has metal bars rather than plastic mesh. If Happy still doesn’t use his wheel, play with him daily and offer him a variety of toys.