I have vivid memories as a kid of observing generally old men walking in the park, hands behind back.I thought they looked cool, open and confident and thought that's why theý did it.
Now I'm doing it because I find it helps with pulling my posture upright and also gives my arms a rest from trying to pretend swing.
I wonder how many of those cool looking old men had parkinsons.
Very insightful! I have not been diagnosed, but I frequently hold my hands behind my back, both for posture and to stop my left arm swinging (because my left shoulder is sore [for 3 years now], but I don't feel the pain if the arm is not swinging).
I guess we tend to stoop as we age anyway Bolt.Building that decking won't have helped your arm
Actually my arm and shoulder are much better than they were 3 years ago. Definitely not any worse for the wear. I think building the deck showed me everything is still working pretty good, so psychologically helpful 
Good to hear that.
I'm not a man, and at 66 I don't consider myself as old! But I have had to walk with my hands behind back for a number of years now to keep my back straight. I'm conscious of appearing strange, but it's comfortable, and helps prevent the half shut knife posture!
Im 61 and think I'm 35 - till I pass a mirror.I think its a great look and find it comfort with benefits.Wonder why I mainly remember old men like this.
👍🏻
Maybe not Parkinson's but as the aging body contracts or compresses (one can lose several inches in height) there may be progressive curvature to the spine which forces your torso or upper body posture into leaning forward relative to the seat of the spine more than it wants to, and perhaps not behind the back then is natural response to influence or minimize the out of balance effect. Many people are born with exactly such imperfect curvature to start. Just a guess.
Could be
I was born with a small bit of scoliosis, which I've been told is rather common. Maybe it's limited to folks like that. I know I get increasing lower back pain all the time now and my father had the same thing (but he also had Parkinson's).
I get mid back muscular pain when standing doing close repetitive work like peeling potatoes or washing pots. Mines definitely pd related.
Yep, I used to say I was 5ft-10 inches , but I was only 5ft nine and 1/2 not including the hunch back , (born with a slight curvature ) but during my last visit to my doctor's office the nurse measured my height and said 5 ft -6" . I made her measure again and she confirmed 5 ft-6 inches. Unbelievable , I think you are right about it being increased curvature because my back muscles and neck are complaining constantly and only reduce the cramping when I take a dose of LD/CD . I find myself with both hands around at my back pushing hard on the muscles over the kidneys and leaning backwards. Of all the problems created by the PD , this one is the most debilitating and requires concentration to bear. Nothing however matches the pain associated with passing a kidney stone and it would look similar except for the banging of their heads against the wall and loud words .
I know, same thing happened to me, both with the height thing and with the aching pain quickly in lower back, the pain thing started 3 years ago but wow I can't just stand at the sink anymore or even sit at my computer desk very long (of course my shadow cat always follows me and gets on the keyboard anyway I am her base of security so she follows me around because wherever I am she can explore cuz she feels safe but it gets old fast cuz she's always in my workspace. Siamese do this but I can't have any other cat because I'm allergic and Siamese aren't very allergenic.)
I do this stretch as part of my stretch exercises which helps. Though not as well as demonstrated 😀
Okay will try it.
I've been thinking this for the last year because before my frozen shoulder, it was the only thing that stopped my hand tremor.
Pain with walking
Walking with John Pepper
Ahlskog explains Dyskinesia 
Early signs of chronic anxiety as a subset of Parkinson's Disease
