Is stationary bike a weight-bearing exercise?

Wolff's Law: Yes...But controversial answer. Weight bearing exercise such as walking is good for your bones (osteoporosis) because of their response to stress and impact. This leads to strengthening of your bones known as wolff's law. While technically not bearing weight, stationary biking and elliptical use do cause resistance (muscles tug on bone) thus also strengthening your bones to some extent.