I mean you will gain weight. So I have a tendency to put on weight, but eating a ton eventually and randro and 4andro, I gained a lot of LBM. BUT* not only gaining to baseline (plus a few pounds of water retention) after 45-50d refeeding ( I was pretty scared to add meat for a while, *just in case* and didn't crave it really, but added whey first and also some pea protein (vegan)).
---SO gaining weight with refeed a bit so I was down 20lb (now I'd be down like 15lb sooner, metabolism was BAD back then compared to now).
---BUT a lot more because of working out a lot... and ghrelin, insulin response, gh, and all that...
---With the right stimulus (training, sports), it will all be LBM after a long fast or close enough, especially with other tweaks like Fasted Training.
-I was primed to pack on LBM. And
@Orion must have gotten a ton of gains in that regard from 40days Breuss or maybe it was 56d.
--I think you have a decent to good maybe very good metabolism (in good health)
@cnb30. You didn't gain weight on an AAP. That's pretty crazy. I mean abilify may not be that bad for weight gain versus a lot of other similar meds. Like Lamotrigine I could lose weight (tho probably in a bad way... maybe make me too fast)... but most these meds are terrible for metabolism... and even then, some have opposite reactions (would gain weight on Lamo).
DOING nothing but getting back to half then .6 .7 and 1.0 x your normal caloric intake will put on weight (but it may not be a ton).
If you're talking about purposely gaining fat... I don't know man. Maybe you're an ectomorph, or more likely it's just a phrase.
I was underweight 10-12 lb maybe like half my 20's but it's not like I *wanted to gain fat*. I realized, yeah you need fat and lean body mass, but the goal should be to get stronger... not put on fat... but put on weight - but more specifically lean body mass with minimal fat gain. OR if you need fat and LBM... then eat like crazy once refeed is well underway. OR after it more likely* when digestion is solid, with betaine HCl and enzymes. But recreate those first, refeeding like
@mattyb posted (on the wiki).
If seriously underweight, you would do well to calculate your Total Daily Energy Expenditure (TDEE). I had notes on this, but am pretty good with estimating (myself), bc of years of doing things like that. --I had notes (deleted). --Emma Leigh - Bodybuilding Forum has a good writeup.