Alvarez grew up in Yokosuka, Japan where he first played for the Nile C. Kinnick High School Basketball Varsity Squad. Shortly, after finishing high school, he flew to the Philippines and attended at Ateneo de Manila University where he became a pivotal part of the Blue Eagles basketball squad. At Ateneo, he was known for his tenacity and hustle plays. Thus, as a sophomore in 2000, he won the coveted UAAP MVP award, beating the likes of King Archer Mike Cortez, fellow Blue Eagle Enrico Villanueva and UST's Cyrus Baguio.