A model that recognises that disability isn't caused by someone's impairment or physical conditions - instead disability results from inaccessible environments, pre-conceived ideas of what people can and can't do, and lack of support systems.
The social model of disability is a way of viewing the world, developed by disabled people.
The model says that people are disabled by barriers in society, not by their impairment or difference. Barriers can be physical, like buildings not having accessible toilets. Or they can be caused by people's attitudes to difference, like assuming disabled people can't do certain things.
The social model helps us recognise barriers that make life harder for disabled people. Removing these barriers creates equality and offers disabled people more independence, choice and control.
With regard to cycling, the social model of disability would argue that cycling is available to many disabled people who can't cycle now. But what is preventing them from cycling is not their disability, but environments that make cycling difficult or impossible for them.