I wear a TENs unit, but never bother in the park. I use a lidoderm patch, Advil liquid gels and wait until I get back to the hotel at night for the TENs. By the time you would unplug the lines, even if you left the pads, if they got wet could short them, and the pads likely would peel off.
I packed mine in the bag and if I really needed it I could sit with it on. But then I generally forgo all water rides.
I had mine on all day last week when we went out for a Sunday and the patches were sweating around or heat made them loose. Two were attached to my shirt. I had it turned off at the time, the battery needed to recharge but I did not want to fuss with taking off on the way home.
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