McSpadden, now a firefighter with the 127th Civil Engineer Squadron at Selfridge, began boxing at age 6, guided by a grandfather who owned a gym.
"I lost my father when I was four," the Detroit native said. "My grandfather gave me a place to release my frustration. Really, I've been in the gym ever since."
McSpadden spent his teen years and early 20s boxing, keeping his focus the positive attributes training in the gym, rather than some of the hardscrabble realities of life. At age 20, through a variety of circumstances, he became the legal guardian of two younger brothers.
Even with that challenge, McSpadden kept at it in the gym, running up a 52-0 record in amateur fights, not only in his hometown of Detroit, but in a circuit that took him to cities around the U.S.
And then, came his first loss.
"I lost to a guy I used to spar with. And I could have beat him," McSpadden says. "What happened was I didn't train properly. I lost focus.
"My trainer asked me 'how bad do I want this?' That's the question. Are you willing to do what needs to be done to get to where you want to be? He told me that day, after I lost, that 'Winners do what losers are afraid to do.' I never forget that.
After amassing an extensive amateur record of 168 wins against 27 losses, McSpadden, who spent most of his career boxing in the middleweight division (161 pounds), suffered an eye injury and decided to hang up his gloves, at least as an active competitor.
"It was hard, because for a long time, I thought boxing was all I could do," he said. "I was trying to figure out what worked for me. But I began to realize that the approach to training (for boxing) applies to other things as well."
With his two younger brothers off to a strong start - one enlisted on active duty and another is in college - and now a family man himself, McSpadden enlisted in the Michigan Air National Guard. Initially, he enlisted in an aircraft maintenance field, but when a slot opened in the fire department, he jumped at the chance.
"I have to admit that I didn't realize the opportunities that are available to a person once they get into the Air National Guard," McSpadden said. "I always had wanted to be a firefighter and now here I am. I'll tell you this without question -- the Guard takes care of its people."
Now, along with serving at Selfridge - McSpadden is temporarily on active duty with the fire department as part of his initial skills training - the Airmen works along with a few friends to help teens and young men in the inner city use boxing as a means to direct their lives in a positive manner.
"I'll tell you this: Onnie is one positive dude," said Domonique Dolton, a nationally ranked middleweight boxer from Detroit. When Dolton isn't traveling - he's held several regional boxing titles and is ranked in the top five nationally as a professional in his weight class - he helps out McSpadden in the gym and talks to young people with the off-duty Airman.
McSpadden is "trying to leave hope behind for the kids on the street," Dolton said. "He's always talking to kids, trying to get them out of whatever their mixed up with and show them the positive way."
For McSpadden, that "positive way" is physical - in the gym - and spiritual, through his church.
"When I see someone on the streets, acting foolish, I tell them to take it to the gym, take it to church. Turn that energy into something positive," McSpadden says.
These days, even though he's not fighting competitively anymore, McSpadden spends about 90 minutes a day, every day, in the gym, following a boxing work-out regimen.
"Its what helps to keep me focused," he said.
About the 127th Wing
Comprised of approximately 1,700 personnel and flying both the A-10 Thunderbolt II and the KC-135 Stratotanker, the Michigan Air National Guard's 127th Wing supports Air Mobility Command and Air Combat Command operations by providing highly-skilled Airmen to missions domestically and overseas. The 127th Wing is the host unit at Selfridge Air National Guard Base, which marks its 98th year of continuous military air operations in 2015.