Understanding Compound Bows Basically, the energy stored in a compound bow at full draw is still stored in the limbs. Several factors control the "power" of the bow. Let's take a look at some of these factors: Draw Weight- Amount of force necessary to draw the bowstring. Draw Length- How far the bowstring pulls back from rest to full draw. Let-Off- The decrease in tension needed to hold a bow at full draw. Can be anywhere from 35% to over 75% less tension than required in the middle of the drawstroke. Cam Design- Basically, larger, more aggressive cams give more speed. They are also harder to draw, though, so there are benefits and drawbacks to any cam. Brace Height- This is the distance from the string to the grip of the bow. Longer brace heights can be a little more forgiving of form, since the arrow doesn't travel quite as far on the bowstring before it is released. http://www.huntersfriend.com/bowselection.htm#energystorage The Force Draw Curve graph above shows the amount of energy stored in the bow at full draw (dark gray area). Increasing this area under the curve by increasing draw length increases the power stored in the bow. By increasing the draw weight, the height of the curve would increase, increasing the area. By increasing the draw length, obviously, the length of the curve would increase. Changing the brace height (distance from string at rest to the handle of the bow) would effectively increase the powerstroke, which means the curve would have a steeper slope initially. As you can see, making power in a compound bow is quite possible. The side-effects of these adjustments would make the bow more difficult to shoot, however. Changing the weight, length, or duration of the bowstring's travel changes the shooting characteristics of the bow, so any adjustments and potential benefits should be carefully weighed against the drawbacks.