"We were in a family environment,” Niall McCann told The Telegraph. “Being undressed wouldn't have been appropriate in the circumstances."

McCann and his rowing partner, James Burge, spent 67 hours, 24 minutes and 14 seconds rowing 1 million miles on a machine. They did their work in 1-hour shifts and kept themselves going through the nights by watching videos of “The Office” and “24.”

The rowing machine was set up near the gorilla enclosure in the zoo because McCann and Burge hope to increase public awareness of the threat of the illegal trade in bush meat.

They said that during the day the zoo was a fascinating place to be, with zoo-goers stopping to look and gorillas watching them.

The partners are planning to enter the Atlantic Rowing Race. That one they may do naked because they say clothes chafe when they get wet.