Dont do these exercises!

Upright Rows
The problem with this exercise is in the positioning of your arms.This position creates what is called an "internal rotation". Every time you raise the weight a small tendon in your shoulder gets pinched(known as impingement) by the bones in the shoulder.Over time the tendon will gradually become worn down and damaged. It's not a matter of if it will eventually wear out but when.  

Behind the neck shoulder press or behind the neck lat pull down
These are the two that will wreck your shoulders. This time it's the "external rotation"that will cause the damage. With your elbows or hands behind your ears the rotator cuff can no longer stabilise the shoulder joint. This action will cause the joint itself to "grind" every time you do a rep. Over time this can cause serious damage to your shoulders.Never do any type of exercise where you need to place your hands or your elbows, what i call the high five position, behind your ears.

The bent knee sit up
Walk into any gym and you will see people lying on their back,knee's bent, doing dozens of sit ups. This type of action causes the hip flexor's to pull directly on your spine creating a tremendous amount of strain on your lower back. This exercise will certainly make any bad back worse or create a back problem.

Next week I'll tell you why ,dumbbell flyes can damage your shoulders. The leg press can do some serious damage to your back and why you never, ever want to do "Helicopter twist or Torso rotators".

Stay Focused
Eric