because as you rotate your hand inward (palm facing your body) at the end of the rep, you put emphasis on the brachioradialis. Its almost like a hammer curl at that point.
I noticed that when I am doing bicep curls with dumb bells if I finish the move when I lower the dumb bell and the palm of my hand is facing outwards seems to hit my biceps a lot harder than if the palm of my hands is facing towards me. What is the difference?
Years ago when I trained with body builders they always seemed to turn the wrist at the end of the move to where the palm is facing their bodies.
because as you rotate your hand inward (palm facing your body) at the end of the rep, you put emphasis on the brachioradialis. Its almost like a hammer curl at that point.

You should do both curls, they target different muscles and it will give you more complete development and strength. I follow my barbell curls with hammer curls (This is after my back workout and biceps and brachs are tired). Alternate them if you wish but include them in your program. The brachialis lies beneath the biceps with the function of flexing the elbow with the biceps. The brachialis benefits from the hammer curls and is stronger than the biceps (that is why you can perform hammer curls with more weight than regular curls). When you perform the hammer curls you can increase its size which will raise the biceps making your arm bigger. The purpose of the biceps is to flex the elbow and to rotate the forearm. The brachioradialis (located mainly on the forearm) also benefits from the hammer curls and you will have strong forearms.


If I may play devil's advocate for a moment, here.....
ROWS! PULLUPS! CHINS! PULLDOWNS!!!
Use these handy little nuggets for a while, and, when the dust has settled, if you feel you need some extra work on those biceps then go with some isolation.
Hammer curls are fine, but you get a really good stretch with preacher curls.
But, seriously....try chins with DB strapped to ya'....your biceps will hate you! But, you'll love your biceps! It's a love/hate thing.
My humble opinion is that beginners and intermediate lifters are better off doing the heavy compound movements you mentioned and staying away from the isolation movements. Too many of the guys in the gym are too consumed with hitting the T-shirt muscles, chest and biceps. I often see the trainers showing newbies how to do several different bicep movements and practically nothing on the core exercises.


But, in the case of incline (or any) dumbbell curls your torso is relaxed on the seat and your arms are just "hanging". The dumbbell may be pulling at the bottom and giving a "stretch", but it's only one-way.
With preacher benches, not only is the barbell (or DBs) pulling on your biceps but the rest of your body is sandwiched in there in a way that your upper body is also pulling. It's like a game of tug-a-war. It also gives you nice leverage. This is why preachers give such a nice stretch.
Nevertheless, no lift gives your biceps a greater stretch than pulls and chins. I can grab some medium-weight DBs for curls or I can hang my 193 lb body off a chinup bar and pull the f'er up!
Hmmmmmm....decisions, decisions.


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This may hurt a little... - Training Journal 2012
Disclaimer: All health, fitness, diet, nutrition, anabolic steroid & supplement information posted here is intended for educational and informational purposes only, and is not intended as a substitute for proper medical advice from a medical doctor. We do not condone the use of anabolic steroids (AAS), all information about AAS is for educational and entertainment purposes only. If you choose to use AAS it's your responsibility to know the laws of the country that you live in. Consult your physician or health care professional before performing any of the exercises, or following any diet, nutrition or supplement advice described on this website.




http://www.getlifting.info
This may hurt a little... - Training Journal 2012
Disclaimer: All health, fitness, diet, nutrition, anabolic steroid & supplement information posted here is intended for educational and informational purposes only, and is not intended as a substitute for proper medical advice from a medical doctor. We do not condone the use of anabolic steroids (AAS), all information about AAS is for educational and entertainment purposes only. If you choose to use AAS it's your responsibility to know the laws of the country that you live in. Consult your physician or health care professional before performing any of the exercises, or following any diet, nutrition or supplement advice described on this website.
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