Velorians are a genetically-engineered race whose initial DNA came from the Scandavadian tribes of Earth at approximately 1000 AD. An ancient space-faring race filled the roughly 80% of unused gene sites in the Velorian's DNA with genes from other races they had found during their travels or genes they synthesized to give them unique abilities.
Their robust physique requires tremendous amounts of energy which can be absorbed from nearly any source and is stored in their bodies. Energy depletion results in weakness and then unconsciousness with temporary (and in some cases permanent) amnesia, even after regaining their energy.
Energy is stored in a female Velorian's breasts (which are no longer mammary glands) and is connected by superconducting nerve fibers to every part of her body. This characteristics results in significant changes in a Velorian femme's figure depending on how much energy she is holding. Since hugely expandable energy reservoirs would be hard to bury inside a person's body, this adaptation to use external energy storage was a creative piece of engineering on the part of the Ancient Ones.