”going for a walk” is nothing compared to a decent gym regime.
That is open to discussion and it depends on what you go to the gym for?
The gym might be good if you want to target certain body parts but those who are looking for overall fitness will have no need of a gym.
Walking briskly a few times a day will burn more calories than a 30 minute gym workout and you get the benefit of being outdoors and breathing fresh air. And it’s free.
Apparantly those who walk regularly have lower BMI and smaller waists than gym goers and it’s also easier on the joints. Studies say that walking beats all else for fitness.
If you are a walker and also a gardener then you are bending, stretching, digging, getting sweaty and out of breath, doing all sorts of cardio vascular things. Perfect work out and a lovely garden to boot.
If you enjoy walking and gardening and have a house and do your own cleaning….. see above for bending and stretching.
Sorry, disagree, nobody really needs a gym to keep fit.