It’s good and brave that sportscaster Mike Adamle has gone public with his battle with the effects of brain trauma likely caused by his years as a football star.

And it’s nice he shared it first, for public consumption, with Peggy Kusinski, his co-worker at Ch. 5.

“Peggy has never gotten the due she deserves,’’ Mike said. “She’s been right there in the sports trenches doing everything the same as us guys for years.’’

But Mike’s pain wasn’t news to those of us who see him often, who are, indeed, his trusted brothers in arms from back in the day, old football pals from Northwestern, when we were young, silly, ferocious and — we believed — invincible.

In fact, the chronic traumatic encephalopathy-like symptoms that Mike is now showing have been manifesting themselves for many years. As far back as 1999, he would occasionally have tiny, non-verbal, almost undetectable seizures on air, the result of epilepsy, itself caused by football trauma to the brain. For years, Mike had needed to frequently change his anti-seizure medications in an attempt to control the symptoms.

Adamle was an All-America tailback his senior season in 1970. No single tackler could bring him down. Mike would take a blow, spin, get hit again, regain his balance and finally go down under an onslaught of late hits. Even from the sideline, you could hear the helmet-to-helmet crashes. For an underdog football team, he was courage incarnate.

As we sat on his living-room couch at his suburban condo Thursday, we stared with dark humor at the framed photo of him scoring over the huge Purdue line, his helmet ripped off, rolling on the ground.

“My neurons are becoming morons,’’ Mike said with a chuckle.

But the black wit only goes so far.

“This would be funny if it weren’t so serious,’’ he said. “I know I’m just keeping the wolves at bay.’’

He has been diagnosed with dementia, and now, at a youthful-looking 67, he keeps an anti-inflammatory diet, drinks no alcohol, sips nourishing tea, stays as active as his deteriorating athletic skills will allow him and tries to keep his mind active.

It’s hard. Very hard.

He just returned from a trip to Utah, where he tried to ski on the bunny hill at a slope. Once a very good skier, he fell and had such difficulty trying to get his boot back in the ski that he quit. His balance is fading. His racing bicycle — he used to take 100-mile spins into Wisconsin and back — has been replaced by an old-fashioned bike from his wife, Kim.

We joked that we’ll ride tricycles when the time comes. In the past when we rode, he would pedal a mile or so ahead of me, then race back, then do it over again. Come spring, we won’t see those days again.

Whereas once there were adventures of all crazy sorts (Mike once produced a photo of him and Bruce Jenner on the back of an elephant in Thailand), including multiple Iron Man completions, Mike now settles for ballroom dancing (which is getting more difficult), calisthenics and punching trainer’s mitts.

“The boxing combinations — you know, left jab-right hook-left jab — that’s good for my memory,’’ he said.

He occasionally repeats himself now, and sometimes he’ll get lost in the middle of a statement, frowning as he tries to figure out how he got there. He went off television broadcasts almost a year ago, when he knew he couldn’t handle it anymore.

“I forgot Allison Rosati’s name on air, and that was it.’’

CAT scans of his brain have shown that from 2008 until 2015, he lost roughly 12 percent of the organ’s density. None of the things he has lost are coming back, and he knows this.

His dementia has all the hallmarks of CTE, and doctors have said that condition — from head-banging — is likely the culprit. But CTE can only be determined for fact in a deceased and dissected brain, so …

“Giving up things you used to have is hard,’’ Mike said. “You get depressed, and you don’t know how to get out of it.’’

There is paranoia, restlessness, anger, sadness. Kim mentioned how Mike will walk back and forth, back and forth, across the living room “like a caged lion,’’ lost inside the steel bars of the present.

But we old friends go way back, and we swore allegiance to each other in the collisions and sweat and blood.

I’ll be there for him. And so will other teammates. Just as someday Mike may be there for us.

Follow me on Twitter @ricktelander.

Email: rtelander@suntimes.com