How can I get a better arm workout during Zumba?

You can get an arm workout from Zumba, but most students tend to have mushy arms or not keep their arms high enough.  When my upper arms are parallel to the floor, I see many students with their upper arms angled 45 degrees downward.  Here, I'll just go over a handful of arm movements to get you thinking about how your can use your arms during Zumba.  Choreography will often involve switching off between mushy and sharp movements, so don't go just sharp or just mushy all the time.  The mushiness or sharpness can be felt in the music and your instructor should lead whatever is appropriate for each portion of music.  See the video for examples. http://www.youtube.com/watch?v=52DVo2kqpZM

Try this:

1)Freeze your arms.  Freezing them for a moment requires a sudden, sharp stop.  A sudden stop takes a lot of muscle control. So get an arm workout by having less mushy arms and more sudden freezes.  You'll look more dramatic too.
     Try the tricep freeze to the side.  First draw your right arm across your chest.  Keeping your forearm parallel to the floor, quickly draw it to the right till it comes to a sudden stop with your upper arm almost perperdicular to the floor. Hold there for a moment, or as music allows.  You will be holding it in a tense position.
     Try this bicep freeze. Use a sudden upward movement as you bend your elbow. It works well with a pelvic rock.
     Try an overhead arm sway. sharp arms to one direction.  This goes well with walking forward or backward or doing a hip bump or twist in a circle.
     How about forearms fan out to side?  Keep your elbows next to your waist and fan your hands out to the side. End with a sudden stop. This works well wth a jump to either side.
     Or try the sprinkler.  Hold your arm straight forward and move it sharply to one side on each beat.
     Try the arm push forward.  This goes well with a booty hop back or heel jacks.  Snap those arms forward and hold them in the tense position for a moment as the music allows.
     Don't forget arm circles.  Small arm circles are usually done during very fast music and accompanied by fast movements elsewhere in the body.  Hit each beat sharply during an arm circle, so people can see the music in your arms. no mushy, boring circles.  Even on a slow hip circle or corkscrew, you may do a slow arm circle overhead, like a lasso. Again, try to accent the beat.

    
2)Retraction: After you freeze your arms on some moves, like a punch, there is a small and sudden bounce back, where you arm muscles are still tense and working.  When you punch, if you move slow and mushy, your opponent will see your arm coming.  Imagine your arm movement is like a punch- you don't want anyone to know it's coming.  Rather, it's like a sudden surprise.  You also don't leave your fist, in your opponent's face;  you quickly draw it back.  Retraction could be done on many of the above moves, depending on the music.

3) Bend and Straight: Even when you're not freezing your arms on a sharp move, your arms may still be working back and forth.  For example, look at the basic merengue march.  Rather than just keeping your elbows bent as you swing your arms back and forth (not much arm work there), try straightening the elbow as the arm goes back and bending it as it comes forward.  On the straightening movement, you'll be using your tricep.  On the bending movement, you'll be using your bicep.  Try the same on a charleston step, but add a little more swing to the arms. Try the same while holding your arms up, parallel to the floor and bending them from right to left, during the merengue 3 step, for example.

4) Mushy, Snake arms:  At a softer point in the music, we often do this softer movement, which still keeps the arms engaged because you have to hold them up, parallel to the floor.
a) Ribcage slides right
b) Elbow leads to the right
c) Elbow straightens and wrist leads to the right.
d) Fingers stretch right
e) reverse process, but elbow draws in front of body, engaging bicep

5) Mushy, Thick swamp: This has to be a part of your imagination.  If you imagine that you are moving through molasses or a thick swamp, you will engage your arm muscles to get through.
     Move out of my way:  Start with your right arm extended straight out and to the left. Then draw your hand to the right, clearing a path in front of your body.  This works well with jazz walks to the left at the same time.  It also matches a side step, together.  And it's very common during the Flamenco Ole.