the.com/tubing

means The leisure activity of drifting along a river or lazy current while sitting inside an inflated rubber tube.

from From 'tube,' tracing back to the Latin 'tubus' (a pipe). The rubber inner tube itself was a byproduct of the bicycle and automobile age — those discarded tire tubes turned out to float beautifully, and by the mid-20th century sun-baked Americans had repurposed them from tire innards into river recliners, giving the noun a lazy new verb form.