10 month old clenching fists & tensing

[Newmum26]

My LO has started to find it amusing to clench his fists and jaw and tense his whole body and make himself shake for a few seconds while making a 'Huuuuuh' sound.
It's like the sound they make when the New Zealander's are doing the Hacka 🙈
It's so forced and he looks for a reaction when he does it.
He does it when he's excited about something.
Anyone else's baby do this?! X

Yes! My 11 month old does this. She sticks her tummy out, goes red in the face and does the hrrr sound. She looks like a right little bruiser!

😂😂😂 my 6mo has been doing this over the last month and it is HILARIOUS. He sort of makes a grrrrrrrrr sound when he does it as if he's cross (he's not though). X