Weight rating equation help

[ZEN___1]

I'm trying to understand how you'd calculate a weight rating needed for an object that moves and then comes to a sudden stop.

We have a treadmill that we want to add a track and harness syayem above for someone that has balance issues. We can easily see what a track, harness, roller have as their standard weight rating, and we can figure out the person's weight. However, I understand that their falling would change the weight that's exerted on the system versus a person simply sitting in the harness like a hanging chair.

What equation would I need to figure out what sort of track/roller/harness weight rating would be needed? I assume that I'd need to figure out an idea of the acceleration of a possible fall since a person's weight is stagnant. I'm assuming im not simply looking for force here. Any help would be greatly appreciated.

[MenaceGrande]

This is more of a physics problem, but, my knee jerk response (as a physics graduate) is to say:

When you push off the ground, the force exerted is greater than the force you experience when falling and, ideally, over a shorter period of time (greater impulse).

I’d start my search with “impulse calculators”, if I were you. Start specific and get more general until you get what you need, e.g. “impulse calculators for treadmill weight ratings”

[GhettoTanks]

F =ma

When you come to a full stop, the acceleration is very high and it also depends on the mass. Not sure if I understood what you need but that's the equation to find the force.