Physics actions lag a lot (LinearVelocity)

I’m coding a combat system, and I use Linear Velocity to make players move on hit. The main problem is this all lags so much. My code is fairly optimized I did everythin I can, my code just creates linearvelocity inside of a humanoidrootpart for a couple of seconds, but it causes so much lag. Can anyone help me with this?

https://gyazo.com/4a551dedaf05065a8ee7d9d545c584c1