He is the first Filipino to win a gold medal in the men's individual triathlon event at the Southeast Asian Games securing the feat in the 2015 edition.

He made his official debut in the Elite Men category shortly, particularly September of the same year, at the 2010 Yilan ITU Triathlon Cup.

Huelgas made history on June 7, 2015, when he became the first Filipino professional triathlete to win the gold medal in the 28th Southeast Asian Games,[1] which was held in Singapore.

On August 7, 2017, Huelgas made history once again when he successful defended his gold medal at the 29th Southeast Asian Games,[9] clocking in at one hour, fifty-nine minutes and twenty one seconds.

This led to his non-inclusion to the Philippines' roster for triathlon in the 2019 Southeast Asian Games to be hosted at home due to failing to be among the best two performers in the qualifying events.

He is also commercial model who has had campaigns for the likes of Skyflakes, Cherifer Premium, Samsung, Gatorade and USANA Philippines, and also serves as a motivational speaker.