How would you deal with a subordinate who has a constant strong body odor?

Soap and water.

Med-call for hygiene eval.

I had a Soldier who gagged us out of a MLRS launcher after 1 minute, his room mates said he showered every day sometimes twice a day, turned out his mother would send him a jar of fish in a white sauce from Louisiana every week, it stank to high heaven, and it would sweat out of him, about 3 weeks of him not eating that shit and the smell went away.

Usually a simple hey dude you fucking stink should suffice, no one really wants to walk to the left of the group, it’s tough enough as it is. I bet it’s really bad in the tight quarters on board a ship, especially is you have to share a bunk with a pig. I’d guess the stakes are raised a bit there.

If they refuse to clean even after corrective training; I suggest getting the proper regs together, and council them. If they keep refusing then it will lead to redtrictions, loss off pay, and even grade.

there are two possible solutions.
1 take shower
2 don't take shower

Guess what solution will be most effective.

Well... I think we have all met the SPC (why is it always a Specialist) who wants to be a McNasty and just doesn't wash himself. Maybe he's got an aversion for group showers. Maybe he's just a dirty skunk-pigpen wanna be. Maybe he's got some kind of medical condition.
I GAF.
You will trot your happy ass down to the showers and square that shit away or I will hem you up with an NCO that can "help" you solve that problem.
In extreme cases, you might have a chaptering situation. Not my first choice or my second, but within the realm of options if it comes to that.

It's simpler in the military than in the civilian workplace. There are a number of medical conditions (by number, lots!) that can cause that problem, and there's some protection afforded under the ADA and the State Legislation. However, it's a good order and discipline thing. If you can't get them to be clean using simple standards and discipline, in the service you send them for medical and psychological evaluation and then process them out for inability to meet standards. I was a First Sergeant and developed a simple rule with problem soldiers -- if I was working harder to keep them in the Army than they were, I could do the Army right by getting them out of the way for someone else's rucksack.

I would have to figure out why this grown person doesn't care how they smell. Maybe the SM is depressed. Could the lack of personal hygiene be a cry for help? Or are they just nasty and lazy?
Either way, this person needs to be called in your office for a sit down and have this matter resolved once and for all. Tell him that by not taking care of his body he could be charged with destruction of government property. :)

tell em to shower :)