FRESH 3D bioprinting is performed by extruding bioinks and other materials within the hydrated, compacted LifeSupport support material, which is specially formulated to prevent constructs from collapsing and deforming while printing. A wide range of polymer crosslinking chemistries and gelation mechanisms are supported within LifeSupport by the incorporation of ions, enzymes, pH buffers and more into the support material during the rehyration process. LifeSupport allows for FRESH 3D bioprinting of soft hydrogel bioinks in complex geometries without the need for sacrificial support inks (e.g., Pluronic® F-127, polycaprolactone, gelatin) or ink modifiers to increase mechanical stability (e.g., gelatin methacrylate, cellulose, alginate).