The former Arsenal and England full-back finished his playing days at Bromley, helping the club win League Two last season, in a career that also took in spells at Charlton and West Ham United, and included advice from Arsene Wenger he says he struggled to put into practice.
Jenkinson, who won a single England cap in November 2012 and joined Arsenal from Charlton for a reported £1million that same year, chose to mark the end of his career with a reflective message rather than a standard farewell post.
"Thank you to everyone who played a part in my journey, from my Charlton days as a kid through to my last time playing football at Bromley," the statement began.
"From the age of 8 football has been my life, it's given me a lot, and I have also given it a lot back. In fact I've given it everything."
Jenkinson said he looks back on his career without regret despite acknowledging moments he wished had gone differently, including a notorious own goal.
"It's for that reason that I can write this looking back over my career with no regrets. Do I wish certain things went better? Without a doubt. A lot of things. I once scored an own goal from 30 yards out. I certainly wouldn't mind deleting that from history.
"But were these bad or difficult moments ever because of a lack of effort? No. Like I said, I gave football everything. Everyday."
He was candid about a lifelong struggle with self-belief, describing the message Wenger repeatedly gave him during his time at Arsenal.
"I suffered a lot with confidence throughout my career, which I found strange because my Dad always backs himself to the hilt. I saw loads of people, to try and unlock something within me and find that inner belief. 'Take the chains off' Arsene Wenger would say to me. 'I'm trying boss', I would say to myself. But I'm certain it was that same insecurity that gave me the drive I have, that would make me run harder and train harder than everyone else.
"Ultimately that's what gave me a career at the top level, because physically I was a machine and I took a lot of pride in that. Was the way I am a blessing or a curse for me? A bit of both I think. But you can only play the cards you're dealt and try and make the best of them."
Jenkinson devoted a significant portion of the statement to advice for young players, contrasting the confidence he sees in today's academy prospects with the daily application he believes is still required to succeed.
"I'm writing all this because I hope some young players might read it. You guys have so much confidence these days! I wish I could nick some of it and take it back in time, but confidence without application and having that fire in your belly to improve everyday won't get you far. I see less young players doing extras, working on their craft, doing extra running after training. Trust me, you won't have a career if you neglect this aspect."
He singled out Bukayo Saka as an example of a player who has struck the right balance between confidence and humility, contrasting him with the effort he says defined former Arsenal teammate Alexis Sanchez.
"Alexis Sanchez, wow. Every training session he trained like it was his last. Try and find the sweetspot. That's why I love guys like Bukayo Saka. He's got that swagger, but you only need to listen to him in a post match interview to see he's never lost his humility. Find the sweetspot."
Jenkinson explained his decision to write a more personal message rather than a conventional farewell.
"I didn't want to write the generic retirement 'thanks for everything' post as it seemed like a missed opportunity. Although of course I am very grateful to my friends, family, coaches, managers and of course the fans who have been with me on my journey. I'm looking forward to seeing what life has in store for me next. Cheers, Jenko."
It remains unclear whether Jenkinson intends to stay involved in football in a coaching or media capacity, though his statement's emphasis on mentoring younger players suggests he may look to pass on his experience in some form.