Here`s a little piece of information on how to play forte (Romantic period). Lot`s of people play forte very inefficiently, which makes you get really tired really fast, and it makes some very messy sounding running passages.

On an average Steinway, you would put your finger in the right place, slightly stiffened; and you would use your arm to push your hand down, which would push the finger down. Your finger actually moves very little. The force applied is from your arm.
You come down on the key with a sudden burst of force, then quickly relax with just enough force to keep the key down.

F| ^
| | \
O| | \
| | \
R| | \
| | \
C| | \
| | \
E| | \______________________________
|-/ \
|_________________________________________________
press...relax and hold..................release
T I M E

Some people don`t relax after they press the key down, I`d be tired within 10 seconds if I did this.
_________________________________
F| / \
| | \
O| | \
| | \
R| | |
| | |
C| | |
| | |
E| | |
|-/ \
|_______________________________________________________
press...hold with same force...........release...ouch
T I M E

On a lighter piano, such as a Yamaha, you would rely more on velocity than force, so use your finger more than your arm.

V| ^
E| / |
L| / |
O| / |
C| / |
I| / |
T| / |
Y| / |
| / |
|_/ |_____________________________________
|_________________________________________________
press....key stops...use force to hold down key
T I M E


and I hope I never have to draw with the keyboard again.

Wow...I guess the graphs don`t work. I guess they do that to keep people from posting big long posts of space.

??????What are those graphs tyring to tell?

the strength gotta came from your back. I know it sounds absurd and hard to fathom. However yet once you start utilizing the muscles located in your middle/lower back, you got an endless wealth of strength and big, firm sound.

Er...in the beginning, some back/muscle pain is inevitable.

*back --> shoulders --> arms --> fingers*

works particular well for, well, under-weigh people like I am. Kinda got fed up with being told playing too quiet all my life. Grr.

oh btw, not trying to contradict you Harvey. Just some more extra info...

Say whatever you want.

The back thing---I don`t use it much. On things approximately ffff, I tend to use the inertia of my whole body with my fingers really stiff.
Ummm...like in etude "revolutionary"...the last four chords...yeah. I`ve never busted a hammer or a string before.