"I got out of breath," he told the "Today" show's Al Roker in his first interview since recovering from his daring expedition to the South Pole earlier this month.
"You know, that's nothing new, except that it's a little more concentrated," he added. "It's cold, and you got a lot of heavy stuff and not much air to breathe up there."
Aldrin, who in 1969 became the second person to walk on the moon, arrived at the South Pole on Nov. 29, according to a message from his assistant, Christina Korp, The Washington Post's Travis M. Andrews and Sarah Kaplan reported. He was scheduled to be there until Dec. 8, but his “condition deteriorated” shortly after arriving, according to the White Desert tour company.
Aldrin was visiting the region with a tour group. He was taken to a hospital in Christchurch, New Zealand, where he spent a week recovering from congestion in his lungs. His manager described the evacuation as "grueling" at the time, but noted that Aldrin was in good spirits as his body responded well to antibiotics.
In a statement posted on Twitter while he recovered in the hospital, Aldrin noted that his trip to the South Pole followed other "exploration achievements," such as spacewalking "in orbit during the Gemini 12 mission in 1966," walking on the moon and traveling to "the Titanic in 1996 and to the North Pole in 1998."
“I’m extremely grateful to the National Science Foundation (NSF) for their swift response and help in evacuating me from the Amundsen-Scott Science Station to McMurdo Station and on to New Zealand," the statement said. "I had been having a great time with the group at White Desert’s camp before we ventured further south. I really enjoyed the time I spent talking with the Science Station’s staff too.”
The National Science Foundation, which covered the humanitarian medical evacuation flight, has since acknowledged that Aldrin now holds the record for the oldest man to reach the South Pole, according to Korp.
“He'll be insufferable now,” she tweeted last week as a joke, along with a photo of a grinning Aldrin in his New Zealand hospital bed.
Despite his brush with death, Aldrin struck an upbeat tone in his interview with Roker and made it clear that he has no regrets about the risk he undertook or the suffering he experienced.
"When turning back is about as difficult as pressing on, you press on because you've got an objective, especially when they tell me that I just set a record — the oldest guy to the South Pole," he said enthusiastically. "See now it was worth it!"
The interview also gave Aldrin a chance to reflect on the death of his legendary colleague and friend, John Glenn, the first American to orbit the Earth. Glenn, who went on to become oldest astronaut in history, died Dec. 8 at a hospital in Columbus, Ohio, at age 95.
Aldrin called his longtime friend a "typical, all-American guy."
"I just admire that guy so much, even though he was a Marine," added Aldrin, a West Point graduate who served in the Air Force. "But he knew how to fly that airplane, I could tell you that."
The feisty, smartphone-loving Aldrin has also remained very much in the public eye, once making an appearance on one season of “Dancing With the Stars” — where he did not last long but, of course, snuck in a moonwalk. The animated movie character Buzz Lightyear in the “Toy Story” franchise was reportedly inspired by Aldrin.
Aldrin chronicled his ill-fated journey on Twitter, where he posted several photographs as he prepared to leave for Antarctica, including one showing him outside an airplane with the caption “South Pole here I come!”
Another tweet read: “We're ready to go to Antarctica! May be our last opportunity to tweet for a few days! We're go for departure to the launchpad!”
Another post-recovery photo included a joke: “I'm feeling much better and my rocket is ready for launch."
Aldrin was born in Montclair, N.J., as Edwin Eugene Aldrin Jr. He earned the nickname Buzz because his sister pronounced the word “brother” as “buzzer,” according to CNN.
In 1969, Aldrin, along with Neil Armstrong and Michael Collins, flew to the moon on the Apollo 11 mission. He became the second person to walk on the moon, after Armstrong.
Amy B Wang contributed to this report.