|Is this going to affect me breaking out of prison?|
Researchers in the study induced sweating on two different spots in their subjects. One where the subjects had a tattoo of at least 5.2 square centimeters and the other spot on the same area on the opposite side of the body that didn't have a tattoo.
On average, the sweat rate from skin that was tattooed was about half that of plain skin. The sodium concentration of sweat from tattooed skin was about 1.7 times greater than sweat from plain skin.
This shows that tattooed skin produces less sweat. The sweat was also saltier than skin that was not tattooed. All things being equal, this may result in tattooed runners having a higher core temperature due to a lower sweat rate. Sweat with a higher sodium concentration may also lead to an electrolyte imbalance. And in sunny and super humid Singapore, both can hurt your running performance.
Question is will the same outcome occur when you run or exercise intensely? More research needs to be done in that area as the current study involved induced sweating.
Also, compensatory skin sweating can also occur in other areas that do not have tattoos. I would say that at least half of your skin needs to be tattooed before performance may be affected.
Perhaps the sensory homunculus (having altered thoughts and emotions) as I wrote in tattoos and sporting performance plays a part too.
Luetkemeier MJ, Hanisko JM et al (2017). Skin Tattoos Alter Sweat Rate And Na+ Concentration. Med and Sci in Sports and Ex. Published ahead of Print. DOI: 10.1249/ MSS.0000000000001244.