does anyone else do this?

Stuff...That is one of the elementary training techniques to improve your bat speed.

Try it. You'll like it!

I don't think so. It is a funny thing but the weight ( inertia) of the bigger bat is hard to overcome. Physical strength is the answer. Moving up 5 OZ. probably requires an additional 50 lbs( or possibly much more) on the bench press max to get the same swing.***don't go ballistic ..just and example.....I have no clue the amount.

This is the reason current MLB players are so strong. Heavy bats and rotational mechanics take great strength.

I see WAY too many younger players (especially middle school-freshman) who want to walk out there with the fattest (and usually heaviest) bat in the rack. It's an uneducated macho thing, I guess. And no matter how many times the pitcher blows it by them, you'll see them out there again, hacking away with the same bat. It is not wimpy to use the proper bat for your size, guys!!

"Son, when you pitch a strike, Mr. Hornsby will let you know."

If you are going to do over/under training, use a light bat about 3-4 oz lighter and a heavy bat about 3-4 oz heavier.

i think a few of you misunderstood what i was saying. this year i will be using the high school 29oz bat, but was wondering if i could train with a bat around 33oz to improve bat speed. i just wanna use it for things such as soft toss and war up swings and stuff

Stuff,
I assume you're talking straight aluminum. Perhaps a good middle-ground would be to dry swing/soft toss with a 29-30oz wood bat, then use the metal in games.

"Son, when you pitch a strike, Mr. Hornsby will let you know."

Stuff, yes you could do that.

My son has for several years been taking about half his BP cuts with a wood bat that is typically 4-5 oz. heavier than his game aluminum bat. It has helped. It has had no adverse effects on his mechanics. And it has helped develop more strength in the muscles used in the swing process.

Plus, if you use wood you will develop better bat discipline (smaller barrel diamter, smaller sweet spot).

Go for it.

"Show me a guy who can't pitch inside and I'll show you a loser." Sandy Koufax