Tubing is a great way to enjoy rivers, lakes and oceans from on top of a rubber tube
The term comes from “inner tube” in English. Many Ticos enjoyed this activity as kids, and we used to inflate old car tires that we took with us on weekend trips. Those trips usually involved areas with lots of water, and we would never go on them without a tire. On rivers like the Pacuare, near Siquirres, kids would always be seen on their tires enjoying the “chorros,” as we called the rapids. As tourism developed – particularly adventure tourism – people began looking for new ways to entertain visitors. And what better way to take advantage of the rivers – especially the smaller ones – where larger rafts weren’t an option. That’s how tubing as we know it today was born in Costa Rica, on the many rivers that have interesting currents.
Costa Rica was the first country to begin running rivers commercially using this method. Since then, this activity has grown more popular and expanded to other countries. It’s not a coincidence that Costa Rica is where many commercial adventure tourism activities started, such as canopy tours and bungee jumping, to name a few. Specifically, tubing began on the skirts of the Rincón de la Vieja Volcano. It primarily responded to the need for more aquatic activities when rafting wasn’t an option. But what was once a family recreational activity needed to be adapted to the needs of a growing and more demanding tourism industry. Special life jackets and helmets designed for rivers were needed, among other things. Because tubes often crash against the rocks, they had to be reinforced with a special type of water-resistant canvas. A bottom was added to the tubes to prevent riders from falling through the center. And special handles were added to allow better control without the risk of riders getting caught when flipping over, which could be dangerous. Tubing is described as a descent down rivers on a round, personal raft that allows riders to observe and feel nature in a new and different way. Being so close to the water magnifies everything, and you can really feel the adrenaline surge with this new form of running rivers.

Source: Visit Costa Rica
https://www.visitcostarica.com/en/costa-rica/things-to-do/adventure/tubing