Lag spikes from "Simulation" and "Worker"

[Guest422349]

I have no idea what any of this means, and why it happens.
It only happens when I do a specific thing in the game multiple times.

[Farmboy014]

What specific things are you doing at this time?

[Guest422349]

Using velocities on the player when a key is pressed or in a swimming state. It starts off fine but eventually the lag starts and gets worse and worse.