If construction work broke your body at 30, then there wouldn't be any professional body builders or gymcels older than 32.
The real truth is if you actually have an active job(or gym membership) outside of the dangers inherent in the industry itself, and the heavy machinery, contractors, like gymbros, tend to actually enjoy peak physical health throughout their 30s and 40s
Now once you reach 50, 60 years old is when things don't work so well anymore
My wife's father works for the city and he's been doing real ball busting work his whole life, and he is almost 64 years old and only these last 3 years have I noticed he sleeps longer, is more worn out at the end of the day and one of his arms can't lift anything heavy for long and sometimes not at all.
He also smokes

So I would say so long as you start healthy and young enough(at least gym) you could probably do construction well into your late 60s before you start becoming too old and wore out to do hard labor anymore

Keep in mind, there are much more lightweight trades like carpentry, remodeling and painting that are not so rough that you could probably do it until your arthritis catches up or some other debilitating disease.
Same with landscaping
Many landscapers I know are well past their 30s and have been doing it since 20.
In Florida.
Where it's cooking all day and night