They are used automatically by the vault dwelers you sent to explore the wastelands, i think at around 10% health they use it i got the stimpck part but what about the themes? you said i need to 'reset my vault' does that mean quit and come back or start over? you can, or theres a button on the left that does it for you.

If you choose later, they are reset next time your vault appear out of view S - Weight Room P - Armory E - Fitness Room C - Lounge I - Classroom A - Athletics Room L - Game Room Merging Rooms Building two or three of the same type of room next to each other. Once you do you can apply them to the room they were designed for (either the living quaters or the diner) However, they only appear after you reset your vault, which you are given the option to. To apply them you gotta make them in the theme room and have all necessary materials and bottle caps to craft them. If you do not produce enough Food your meter. Food is vital and sustains all of the Dwellers within your Vault. You get them by having your vault dwelers explore the wastelands, or on quests either they are given to you as a reward or you find them Assigning Dwellers to a Diner helps produce Food, another of your primary resources. Originally posted by Sir Dan The Skeleton Man:themes are made in a theme room (gotta build one first to make themes)

Weight room in fallout shelter