We had a Bernese 30 year ago and boy, did he hate any weather above 20C. He did not want to leave the AC grate for anything. In the winter, you couldn’t get him in the house! He was super quiet though. Did not need a lot of exercise but boy, did he shed!!
Now that I have a Greater Swiss MD (did not want another Berner due to a lot of health issues and the intolerance to heat), and even though she has a short (but double) coat, she’s also not a huge fan of the heat (I guess they really do want to live on the mountains). She doesn’t shed (I’m not sure if its because of her diet or I’m just lucky as all GSMD owners say they shed 24/7 and like mad). But she has a lot of energy and loves to go for long hikes (in the shaded woods preferably) and bike riding. She bikjores really well and can run for quite some time beside me quite politely (she does not walk on a leash well and pulls like you wouldn’t believe - I use a perfect pace halter on her or I can’t hold onto her). I’m actually impressed as I was told GSMD are quiet (can be tough to walk since they are a cart/pulling breed - mine has this 10000%), but I guess I got the active, non shedding one lol! She also loves water and to be vacuumed, also odd for the breed ha ha! I have to walk her at least 4km a day (off leash so she does roughly 10km as shes all over the place!!), or everyone suffers. She is a true working dog for sure!