Would One Day of HIIT Help?

So I’m 5’11, 190 lbs, up from 170 this summer and still on my way to 200 before I level off to maintenance for a while. I notice that I’m gaining a bit more fat that I would like. I know that gaining fat is an inevitibility, but I was wondering if adding in a day of HIIT might help out a bit.

Or, do I need to do at least two? Or should I just say fuck it and worry about it later?

Certainly wont hurt to try and may help.

I’ve added in two days of HIIT to my program and it certainly doesn’t seem to be hurting.
Just make sure that you’re smart when scheduling when to do your sessions, paying attention to recovery, and eating accordingly. I bumped up my calories slightly on HIIT days.
Hope that helps.