The general principle behind many human genetic studies is to compare the genetics of a group of individuals with shared characteristics of interest to a control group lacking those characteristics. Many physiological differences can be observed between athletes specializing in different sports. When investigating the genetic components of elite athletes’ makeup, it is important to know which sport an athlete is considered to be elite in and what the physiological demands are of that sport. Grouping together athletes from sports with similar physiological demands is useful. Participation rates in many sports differ vastly across borders and sexes as do the standards that would be considered to be elite. Within sport there are a variety of ways to define an individual as elite and each comes with its own strengths and weaknesses. Individuals with noncommunicable diseases may have even more in common with elite athletes.