Thanks for the endorsement, but I'm not sure that weight training is totally wrongheaded. However, you don't need nearly this kind of weight, or building up that much strength. You're only trying to gain some minimal strength to hold up your head plus the weight of the helmet or whatever. So, if you want to try weights, limit them to what's called for, maybe an improvised harness and plastic 1 quart milk bottle half full of water (1#), or maybe a bit more. Do plenty of reps at this low load vs fewer reps with a big load.

The goal is to gain a bit of a strength reserve, but it's more about flexibility and movement to prevent spasms than it is about strength.