The scrotum and testicles do not require support in the form of attire such as underwear, although this may be preferred on an individual basis for reasons of comfort. During physical activities involving a lot of jumping and jarring (e.g. running), jockstraps or tighter-fitting underwear can provide support to prevent something akin to "whiplash" from happening to the testicles. Generally the scrotum does not sag particularly over time, no matter the type of underwear used.