Peak height velocity (PHV)
Is a word for the adolescent growth spurt in the height development of individuals. Years off peak height velocity is used as a measurement for maturation in the youth (2).
Portable metabolic device
Is a system (a mask that needs to be put over nose and mouth in conjunction with a little device) that measures cardiorespiratory variables such as, the ventilated oxygen and/or the produced carbon dioxide and therefore measures the VO2max directly.