The 25-year-old came out on top in Glasgow earlier today with a time of 2:38.43, overhauling Emma Pooley - who announced her retirement from cycling earlier this week - in the final 7km to win her second Games medal.
"I am really happy," BBC Sport quotes Armitstead as saying. "That was the best cycling teamwork I have ever been a part of. It's such a shame Emma is retiring today - it was a fantastic job from her and all the girls and I am really proud of them."
South Africa's Ashleigh Pasio claimed bronze in the race.