I was a Marine. We had one of our Scout Snipers go to Ranger School. He was a lean guy. He came back a lot leaner.
I went ADA (Air Defense Artillery), so it didn't matter. Had I gone Infantry, it would have made a difference. The small unit tactics training in ROTC prepared me just fine for one of my extra duties: leading a platoon to augment a nearby Nike Hercules should they be attacked.
That experience was the basis for several of my fondest recollections of my tour in Germany. It was always a challenge, to assemble 40 men who have had zero infantry training after boot camp, and run them through an evaluation at a nuclear capable site. My last one was Dept of the Army level. The out briefing was attended by the Deputy CG. Hell, I was just a dumb LT doing his 4 year active duty requirement. Lol