NBA player Jason Collins’s groundbreaking decision to come out as gay, and the overwhelming public support he’s received so far, is a clear sign of how our sports locker-room culture — filled with its suppression of anything that isn’t overtly heterosexual — is beginning to change, especially compared with my own athletic career in the 1970s.

I was 11 when my dad, a career military man, signed me up for the Vandenberg Air Force Base junior football league in 1974. He worried that his only son — sensitive, chubby and bookish, with three older sisters — would grow up gay.

The plan didn’t start off well: I came home in tears after the first practice.

At a meeting at the kitchen table that evening, Dad couldn’t hide his disappointment or contempt. After I wailed about mean coaches, impossible drills and endless wind sprints, Dad grudgingly agreed with Mom: You can quit if you want.

I can’t explain it even now, but I decided not to quit, and it paid off. By season’s end, I made the all-star team, won the Most Improved Player award and began a path that would lead to a scholarship that paid for college.

But Collins’s remarkable statement brought back other, more disturbing memories about men and our notions of what’s truly male, a list that I’m sure is familiar to many my age: entrenched locker-room homophobia, sexual obsession and a hyper-macho aesthetic that’s a bedrock of American sports culture.

When I joined the Vandenberg Rams in Lompoc, Calif., as a schoolboy, the coaches, a group of Vietnam-era enlisted men, weren’t afraid to use words like “sissy” to motivate us during practice.

Later, playing high-school football in Chattanooga, Tenn., during the late 1970s was no less enlightened for testosterone-fueled country boys. I remember two teammates triggered a strong reaction by pretending to kiss in the locker room, and there were persistent whispers that an offensive lineman was “queer” and should be avoided in the shower.

On my college team in Virginia, the homophobic “humor” got more disturbing.

My freshman year, I went through a team initiation ritual in which my classmates were blindfolded and forced to hold hands while upperclassmen screamed at us (”He’s your brother! You better not let him go!”), then forced to chew onion gum. Our coaching staff, which consisted mostly of former Marines who were born-again Christians, approved.

By my senior year in 1983, however, the coaching staff let the players run the initiation, and things took a sharp turn toward homophobic hazing. My classmates put the freshmen in dresses, drove them far from our campus and dumped them on the street with orders to find their way home. Forced cross-dressing was a bridge too far for me, and I left the room when the skirts came out. But I didn’t speak up to stop it, either.

Given all that, I can’t imagine what kind of hell Collins has gone through, hiding his true self for more than a decade in an atmosphere where masculinity and heterosexuality are the coins of the cultural realm — and there’s always pressure to show what you’re worth.

There’s no doubt things have changed. Collins has received overwhelming support, including a phone call from President Obama. When the leader of the free world has your back in public, you’ll probably be fine.

And for all the macho shenanigans that take place in a locker room, my experience tells me that teammates are teammates, particularly when push comes to shove amid intense competition on the gridiron or the basketball court.

Yet while Collins may ultimately be accepted as a person and player, homophobia and hyper-masculinity continue to be as much a part of pro sports as an alley-oop tomahawk dunk or a bone-rattling blindside sack. Although Collins has smashed an important barrier, I believe it will take a long time for the locker-room culture to completely fall.

Joseph Williams is a political reporter and blogger in the District.