Gasping for oxygen in the rarefied-airs, the body slowly adapts to increase red blood cell count, haemoglobin and oxygen uptake.
The theory is that when athletes return to sea-level, they benefit by being able to deliver more oxygen to the working muscles and improve performances.
Added to that physiological change for Lucie-Smith and some of her team-mates, will be the challenge of completing university examinations while on the other side of the world.
She has two papers to sit while in Spain and has been busy sorting out the procedures to allow her and others in the team to sit their exams while away.
"It's nice to do something not related to swimming," said Lucie-Smith, who is studying part-time for a degree in commerce, majoring in management.
"The distraction is helpful and it's good to have a bit more balance and not just focus on swimming all the time."
Lucie-Smith's parents were keen for her to learn how to swim, and she first got into the water at the age of three. Her mother was adept at tennis, but neither Lucie-Smith nor her brother took to it. She did find some rewards in cross-country running but after winning her first national title in the pool at age 14, she turned to swimming.
"I'm a competitive person and I enjoy an individual sport. I am too competitive when it is a team sport because I want to be involved all the time.
"In swimming, it is just me in the water. It is up to me to go to training and to perform. If I do not do well, I am the only one to blame. I like that aspect of it."
There have been sacrifices along the way - she does not enjoy the same social life as her university friends. But she and her fellow swimmers at the Wellington Regional Performance Centre are close friends out of the pool.
"We are all quite close - we call ourselves a family. We hang out together and do some fun games at houses."
Lucie-Smith, who competed at the London Olympics, was unusually subdued when she qualified for Glasgow in the 4x200m freestyle relay at the trials in Auckland.
"I was happy I had made it for the relay, but I was gutted because I did not qualify as an individual."
She had one more shot in the 100m freestyle but she missed, and collectively the four fastest times did not meet the qualifying standard for the relay.
They were given another chance when they joined up as a relay in a one-off time trial in the final event.
"It was exciting to have all the crowd just cheering one relay team. It was so nerve-racking. The team worked well together to make the time."
Lucie-Smith is determined to be at her best and use the experiences from Glasgow, and the Pan Pacific Championships that follow in August, as building blocks for the future.
"The big goal is the Rio Olympics in 2016. I want to qualify in some individual races. Relays are so much fun but I would have achieved more with individual races."
