Child Clenches fists and stiffens body

Question

I have been having this problem with my son who is 3 now. He seemed to have this most of his life...I am not sure when it started, but it was in infancy. He stiffens his whole body for about 5 seconds....and he shakes when he is doing it. His fists are clenched and he is standing there. He does not fall down or anything... he freezes first, then clenches his fists and stiffens his whole body and starts shaking...then it stops just a few seconds later and he seems fine otherwise. I can't tell if he does it more when he is excited or frustrated or what. I have been trying to research it....I have only come up with "hyperexplexia" so far....but I am still looking.
Please help me figure this out.

Jareddanton · Answer

I am not a doctor but maybe it could be related to a seizure. I would definitely go to the doctor’s. Hopefully nothing serious but it’s always good to know.

mwoodard · Answer

my daughter is almost 10 and she is experienceing the same kind of brhavior, except she does the whole tenceing up thing too and i ask her if she is doing that or is her body making her do it and she says its a feeling inside of her that comes out like that, she explains it almost like an excitment type of feeling....and she has been doing it for years she has almost smacked her face on the kitchen table at supper time. we have gone to see one doctor in salt lake city but they are all a joke in this part of the country. any ideas please!!

mimimamabear · Answer

Hi there, my daughter has been doing a similar behavior since she was 4-5 months old. It used to be she'd open up her mouth really wide, kind of stop breathing for a second and expel a little sound  -it looked weird to me, but it was fairly occasional. I did ask our pediatrician but they told me not to worry about it. 
Since then she's done it on and off, but added the clenched fists thing maybe by a year (or maybe she always did that and I didn't notice it). Now it still happens sometimes, usually when she seems to be overstimulated. it's almost like she's saying "Aah! too much input!" and has to stop and physically regulate herself or something. She can sometimes be very sensitive to sound/loud noises but overall is really normal, quite verbal and affectionate.
Has anyone who posted about their infant or toddler continued to have this issue? I also worry about it if it continues into school years. We are just getting ready for preschool in a few months, and I want to inform the teachers/parents so if they see it they don't worry/or freak out. 

I also worry that my anxiety during pregnancy and in general has caused her to have an anxious/overwhelm response like this, which makes me feel pretty bad!! thanks for reading and responding. This page is so helpful to me. -Wanna be relaxed Mama

madhafu · Answer

i have been having a similar thing with my son who is 2yrs old and the other day i was changign his diaper and he seemed to pin his middle bits between his legs and was so stiff and i could not move him and i worried and pulled his hands and arms apart and he stopped. i noted he was also sweating as if he had to make an effort to do that. i am buffled myself and will be seeing our GP regardign this, i am concerned too!

Regards,
Mum of toddler