[2][3] Vallenilla won the bronze medal in the Clean & Jerk in the men's 89 kg event at the 2018 World Weightlifting Championships held in Ashgabat, Turkmenistan.

[16] Vallenilla won the gold medal in the men's 96 kg event at the 2022 South American Games held in Asunción, Paraguay.

[17] In December 2022, Vallenilla won the gold medal in the men's 89 kg event at the World Weightlifting Championships held in Bogotá, Colombia.

[18] Vallenilla won the gold medal in the men's 89 kg event at the 2023 Pan American Weightlifting Championships held in Bariloche, Argentina.

In September 2023, he won the bronze medal in the men's 89 kg event at the World Weightlifting Championships held in Riyadh, Saudi Arabia.