[Dr. Shon Thomson]

I think there are a lot of factors really. A puppy will need a lot of attention even when you're not walking it. A young-middle aged dog still needs a fair bit of walking - if you rescue an elderly dog then it'll need a lot less. Different breeds need different levels of exercise, huskies and border collies are famous for needing a lot of exercise, small dogs will need a lot less. I have a middle aged german shepherd and I'd say around 1 hour per day is plenty. My border collie cross needed more when he was younger, but now he's older he has arthritis and can only go on short walks.

So if you do not have a lot of time a smaller, older breed will probably be better but they do require a lot of time and energy and a lot of research before you get one