Do Bernese Mountain Dogs need large yards? What about Labrador and Golden Retrievers?

I only have a medium yard. Neither do I want a big yard since I hate mowing the lawn. Bernese Mountain Dogs, Golden Retrievers and Labrador Retrievers are great dogs that have wonderful temperaments. I had a Golden Retriever in a house with a small yard, but I'm not sure if this was actually appropriate. Please tell me if these dogs need large yards. And do Whippets need large yards(you don't have to answer this part but I'd appreciate it if you did)?