How tattoos may affect your workout

Tattoos may permanently alter the physiology of skin in ways that affect sweating. According to a small, new study, the amount and saltiness of sweat change after skin has been dyed, a finding that might have implications for athletes who ink large swathes of their bodies and maybe even for those of us who sport one or two discreet tattoos (such as the small one on my right shoulder, in case you were wondering).

Tattoos are decorative, often metaphoric, sometimes regrettable, but always injurious. To create a tattoo, the artist punctures the skin with dye-filled needles at a rate of up