How can I help my child relax?

My eldest son (five year old) is passionate and sensitive and extremely intelligent. That's all wonderful but he gets really wound up and aggro and angry and doesn't like to try to calm down. I try to get him to do some breathing but I can see his shoulders heaving and hear the tightness and tension in his throat. When he is wound up his whole body stiffens and he clenches his fists and he tears away from cuddles adn doesn't like to be spoken to in a soothing voice and knows if someone is trying to calm him. He flings his arms around angrily and stands "like a superhero" (or an aggressive alfa male, very exaggerated). He doesn't cope with "changing gears" well- even if the changes are based purely on his assumptions and not reality.
I try to get him to breathe deep and although he shows an interest in Yoga he won't do it with me nor are there any classes here for him.
Has anyone dealt with anything similar? Any tips or pointers for us to help our little man cope better?

My nephew does a similar thing, he's 3 1/2. At the moment I deal with it by picking him up and holding him tight - I do this because he has a tendency to hit whatever is around, be it his brother or a brick wall, and I don't want him hurting himself or others. So I pick him up and cuddle him tight for a while. Yes, he objects to it, and yes, he hits me for a minute or so. But then he calms down, and cuddles into me and just cries for a little while, letting out the extra emotion. We go and sit in a quiet, dark room, and more often than not, once he calms down, he falls asleep. Lately this has led to him recognizing that he's getting overwrought, because he'll come up to me and demand cuddles and bed.

Could he have a timeout type thing, not as a punishment, but just to give him some space and quiet time? Does he have his own bedroom that he can go to?

I used to pick him up and cuddle him and eventually that would work but he is very strong and being heavily pregnant now I haven't the strength or physical capacity to subdue him. time outs/thinking time just wind him up further unfortunately and he shares a room with his younger brother...it's a tricky one for us!

You poor thing! I saw a 'timeout jar' on Pinterest the other day - essentially just a jar with glitter and water in it, and the lid superglued on. You give it to the upset child and get them to shake it up as hard as they can, and then sit there and watch the glitter float around and finally settle at the bottom. And hopefully it catches their attention long enough to calm them down. Would that work?

Thanks for the idea, it might be worth a try- I have thought about something like that ( I hope he doesn't just throw it at the wall!)

Hey Jessiebean my ds who is almost 5 has a hard time calming down also and I totally understand where you are coming from... It is so hard to see them so wound up... Things we try - and yes sometimes they work and sometimes not!!.... Is calming music, burning lavender, having a 'chill out' space where he knows is a safe spot just to chill and talk things through or if he doesn't want to talk he just chills there and then a little while later we will talk about things... Like what made his so upset and talk about ways to calm down... It is hard and like I said sometimes it works and sometimes it doesn't...

Though I like Keike's suggestion on the glitter time out - I might go and look into that!!

GL hun sounds like you are doing an awesome job xx

Thank you! Today went well, we nearly had a major meltdown but things stayed at what I thin is an acceptable level and when he found me so tired I couldn't play with him he said " I know mummy, why don't we sit and do humming bee breaths together" and we did and then sat knees to knees eye to eyes (apparently a school thing) and talked about our days. Then he took a deep breath held his hands in prayer at his heart and said "Namaste" ! Hopefully can take it one day at a time and help equip him with what he needs to remain appropriately calm....