No Sweat:Tatoos and Exercise

  Tattooed skin generated les sweat and higher sodium concentration than nontattooed skin when stimulated by pilocarpine iontophoresis .
  Translated : heavily tattooed athletes sweat less not allowing for heat dissipation with vigorous physical exertion which may pose health risks such as heat exhaustion and fatigue and increase risk of injury.
Med Sci-fi Sports Exec.2017 Jul;49(7):1432-1436