Biohacking is a term that many people are starting to use for a type of self-improvement. In many ways, the term is a tacit acknowledgment that your perceived failings are not entirely at your command. That you are at odds with the way your body, biologically, wants to operate.
Sleep is probably the most common one. Getting enough sleep is the key to good health and longevity. Most people, everyone will tell you, don't get enough sleep.