does lifting your hips and bouncing the bar make you stronger on bench?

my lifting partner used to keep good form on the bench press like i do, without bouncing the bar and lifting his hips off of the bench during bench press. but ever since he started doing this he has gotten stronger. he can use about 25 extra lbs during his workout doing this. do you guys think that this is a good way to build strength since you can use that extra weight from the bounce and heaving your hips up a few inches? i guess it would sort of be like doing a 1 or 2 board press because you are heaving the bar the first few inches. let me know what you guys think about this. peace.

There is no point in bouncing the bar. This is stupid technique. When your friend injures his shoulder, he will realize this.

As long as his butt is staying in contact with the bench, then any amount of hip drive he can generate is ok. Constantly having your butt come off the bench is a bad habit to get into. But not as bad bouncing the bar. Boucning the bar has no place in powerlifting, or any weight lifting for that matter.

your friend is using the momentum of the bounce not strength, tell him to stop bouncing the bar and see if he can still do it as easily. it's the same thing as bouncing the dumbell when doing a curl

I agree bouncing is not strength......Its momentum.....If you really wanna see how strong you are give the old Power lifting pause, then push withoput the but comng off the bench...By the way that but thing is bad for your back...

Bouncing it is useless. You want to control the negative...

Lifting your hips is your natural whey to make it easier. This will not help with hypertrophy or strength gains. If you need to lift your hips than get a spotter or lower the resistance. Strict form is the way of the game.