WILMINGTON >> Lyptis Rubalcava wanted to run the Los Angeles Marathon after hearing from fellow classmates that it was “the best feeling in the world.”

But little did the Phineas Banning High School junior know that training for Sunday’s marathon with the San Fernando Valley-based Students Run LA would encourage him to reveal a guarded secret — that he identified as a male rather than the sex he was assigned at birth.

“The amount of confidence I gained from joining (Students Run LA) has really helped me during the coming out” phase, Lyptis said this week after a long day of school, training for the marathon and media interviews. “After I finished the 18-mile race or the 6-mile (5K) race, I felt so confident, I said ‘if I can do this, I can come out to people. I can do it.’”

The transgender teen, who was born into a female body, started notifying his teachers and classmates that he identifies as male and would like to be called Lyptis shortly after joining the after-school training program in October. Once he notified his running coach in early January, the coach made him a different running bib with his new name.

“I just remember being extremely happy about that as I was running,” said Lyptis, who was given the name Luna at birth and came out to his family two years ago. “It just felt good because I knew the paper on my chest or on my stomach had the name I wanted.”

Coach Joe Mendoza, who teaches history at the high school and is the citywide coordinator of the Students Run LA program, said he believes it’s the first time an openly transgender student has run as part of the training program created some 27 years ago.

“There’s no prejudice,” Mendoza said. “I guess we just treat him like everyone else.”

While school officials “got a little nervous and had meetings” after Lyptis started coming out, there is a district policy in place and “everything is going fine,” Mendoza said.

The high school’s principal did not return messages seeking comment this week.

Lesbian, gay, bisexual and transgender students — and transgender ones in particular — often face widespread isolation and bullying as well as lack of acceptance at schools, said Rick Zbur, executive director of the LGBT civil rights organization Equality California. That leads to high rates of depression and suicide among LGBT youths and higher dropout rates, he said.

“Polling we have access to says that sports help kids build friends and to feel accepted, to be part of a team and develop confidence,” Zbur said. “That’s why it’s important that transgender students, like all students, have an opportunity to participate in sports teams that match the gender that they live every day.”

Assembly Bill 1266, which went into effect in 2014, allows students to use school facilities, including restrooms, and participate in sex-segregated programs that are consistent with how they identify their gender, Zbur said.

• VIDEO: Transgender student Lyptis Rubalcava talks about running his first LA Marathon

Lyptis told his friends about his transition first, then his acquaintances and peers. He was initially nervous about coming out to his teachers, but it has gone well so far, he said. As of Tuesday, he had yet to inform two classes of his transition, including in his AP History class because “I keep forgetting.”

“It’s a lot of work that we have to do in the class and it doesn’t really cross my mind as I’m doing that work,” he said.

He has some reservations about coming out to his English class, where he believes not all students are open-minded. During one conversation he had, a student said Caitlyn Jenner’s transition to a female was stupid, he said.

Lyptis, 17, said he now uses the boys restroom at school but tends to go during class time to avoid running into students “that still see me as a girl.”

“This is going to sound odd but I usually come out of the bathroom with a huge smile on my face because … I guess it just feels good and makes me happy,” he said.

In fact, since he has started notifying his peers and teachers, he feels more confident and more sociable overall, he said.

“I don’t necessarily have to conceal myself anymore,” he said. “I can just be who I want.”

Throughout Lyptis’ childhood, there were moments that he believes signaled his gender identity, he said. He hated the sometimes girly clothes his mother dressed him in. He had a crush on a girl in first grade and recalls thinking, “I wish I was a boy so I could be with her.” And once when he had to wear one of his brother’s red shirts for a field trip when he was 7 or 8, he remembered “enjoying it way too much” and not wanting to take if off, he said.

Lyptis first heard the word transgender when he was 14 years old and immediately knew it described him, he said. He told his mother on his 15th birthday by slipping a note under the bathroom door one morning before he “bolted to school.” His mother started crying and shared the news with her father the same day, he said.

“My dad thought it was a phase and laughed it off. But my dad’s pretty cool with it,” Lyptis said. “In public, he’ll call me a he, him, ‘this is my son’ and stuff like that.”

But his mother still calls him by his birth name, he said. When Lyptis publicly presents himself as a male and his mother refers to him as “my daughter,” it can get “really awkward and weird,” he said. While it’s more of an annoyance, he said, “she’s my mom” and “no matter what she does, I’ll love her.”

His parents could not be reached for this story.

Lyptis, who aspires to attend Humboldt University and study marine biology, gets a lot of support and encouragement from his girlfriend, who is his first girlfriend and is “very understanding,” he said. The couple mark their five-month anniversary on marathon day, which also happens to be Valentines Day. He’s hopeful that running his first marathon — and the attention he’s getting as a result — will inspire other transgender students to participate in marathons or similar activities. He also hopes it will help others to realize transgender people are “like everyone else.”

“We’re your doctors, your dentists, your cashiers, your zoologists,” Lyptis said. “We’re everywhere.”