Muscle type-specific responses to NAD+ salvage biosynthesis promote muscle function in Caenorhabditis elegans

► NAD+ salvage biosynthesis from nicotinamide is required for optimal muscle function. ► NAD+ salvage pathway effects on muscle function are muscle cell type specific. ► Inadequate NAD+ biosynthesis in development can affect muscle function in adults. ► Ongoing NAD+ biosynthesis is dispensable for muscle function in some cases.