I've worked in a trades adjacent field and it's really not that bad nowadays, tools do 90% of the physical shit. The weather is more challenging than anything else
Actually it's better than a desk job, it's the "right" amount of movement for the human body on a daily basis, while the inactivity of sitting is very unhealthy. For example, see how animals are walking around all day in nature, humans are meant to do the same. Most trades are not any harder than walking in terms of physical effort