like anything that helps you lift more
a shirt, squat pants
anything like that
does it make you stronger if you train with it or just able to lift more
if that makes sense
by putting on a pair of briefs or a shirt, can you lift more weight?
after learning how to use it, yes.
does a shirt magically enable your pectoral, shoulder, and tricep muscles to bench 100 more pounds? no.
do briefs and suits make your hips and posterior chain magically squat 200 pounds more? no.
an argument can be made that by using supportive gear, it increases the weight used, which increases stress on the CNS, which can make raw attempts "feel" lighter. for example, with a shirt a man benches 600 pounds. without a shirt, he won't be able to bench 600 pounds, he may bench 400. since he has already had 600 pounds in his hands, the 400 pounds will not "feel heavy."
if a light brief is used when squatting, they can protect your hips from injury. i guess in theory, if they prevent you from being injured, they are making you stronger in the long run.
also, don't think by adding gear your bench, squat, and deadlift will shoot up. it takes a TON of time and knowledge to learn these peices of equipment.
hope that helped. i tried to put it in layman's terms, because you do not seem to know too much about powerlifting gear.
also, if you are lifting for football, you should probably stick with lifting raw.