The Wanaka Mitre 10 workers and self-confessed couch potatoes took up Mr Watson's suggestion that they could complete their own personal challenge and decided to swim to Ruby Island before Christmas.
Last Saturday the pair not only achieved that goal - they doubled it, swimming the 700m to the island and then back again, in about an hour, because the support boat which was to have transported them back from the island did not make the voyage.
The first leg of the journey was more taxing than the second, as they took time to catch their breath in the cold.
"It wasn't as bad as I thought it would be.
"It was freezing but I put my mind to it and went for it, basically.
"It was better coming back," Mrs Tempero said.
Mrs McMillan was "just stoked".
"I couldn't swim on the way over, but on the way back? Yes!" she said.
The women have noticed many benefits from their year-long challenge, including improved health and fitness and the pleasure of exercising with friends to achieve a goal.
"It's a personal thing, really.
"It's been a good thing, weightwise and body-wise, and getting me out of my comfort zone, really," Mrs Tempero said.
"I don't want to be sitting on the couch.
"I want to do something," Mrs McMillan said.
"The next one I would like to do is bike to Cromwell.
"You must set yourself wee challenges and do them," she said.
