I regularly kayak long distances in rough conditions, backpack, jump rope, practice yoga, play hockey aggressively with people half my age, and engage in calisthenics, and have been for ~20 years. Currently in my mid-40s, I am never more sore than after a few hours of pulling weeds in my garden.

And if you any taller than average, your back and bottom will hurt from short tool handles and constant crouching down and back up!

I wouldn't be so sure. I did a load of gardening over the weekend, and it involved heavy things. I'm sure I got more exercise to more muscles in my body than I would if I had gone on a bike ride.

I'm guessing you mean motorbike and the person you're replying too thought you meant bicycle...

I am guessing they didn't: gardening can be serious work. It also depends on the type of gardening, the size of the garden, available equipment, etc.

Just like you can do a 3km/2mi leisure bike ride, or bike ride for strength (eg sprinting uphill) or endurance you can do the same with gardening.

I am also guessing you've never covered any serious area with a garden hoe. :)

you're right, i haven't!