Source: Hicham El Guerrouj Image, Creative Commons: http://upload.wikimedia.org/wikipedia/commons/3/39/Carlos_ga..jpg; Weight lifting image, Public Domain: http://en.wikipedia.org/wiki/file:Dexter_Jackson_IFBB_2008_Australia_4.jpg
A type of physical activity that gradually conditions slow muscles to work for longer periods of time.
A substance found naturally in muscles or used as a supplement to replenish ATP during muscle workouts allowing muscles to sustain activity for longer periods of time.
A pigment that binds oxygen for the use of ATP production.
A type of physical activity that increases the size of the muscles and has an affect mainly on fast muscle fibers.