Quote Originally Posted by Moxie View Post
Partials reps only strengthen the muscles at that specific joint angle. AKA if you do curls only extending your elbow 25%, you will only gain strength in that upper 25% of your range of motion, you WILL NOT get stronger at the rep ranges below (the bottom 75% in this case). So, if you have trouble locking out your bench....do partials in the top 25% of your range. If you have trouble coming out of the hole on your deadlifts, train partials at the bottom 25% of the range.

When it comes to size, there really isn't a place for partials in my opinion, full range=full stimulation throughout the muscle=complete breakdown of actin, myosin, titin, the sarcolemma, etc. leading to greater hypertrophy adaptations.

Also, if you look at the amount of torque applied to the elbow joint during this guy's preacher curls, there is barely any. Muscles cannot sense force, ONLY TORQUE (rotational force) which is force "opening" the elbow during a curl, pulling it into extension. If you look at that dumbell when this guy is doing curls, and think about the biomechanics, most ALL of the force from that 150lb. dumbell is being transferred downwards pushing his elbow down into the preacher pad, only a small percentage of that force is being transferred into TORQUE which is what pulls the elbow into extension and makes the biceps and brachialis contract to slow the extension/flex the elbow back up. This is why when the guy dropped the dumbell down to about 90* he couldn't stop it from falling to the ground (most of the force from the DB was then transferred into "opening" the elbow into extension, and he couldn't handle it).
Good post, and your 100% correct, i also agree with K-sugo. There is a place for them, i personally dont do them though. In time i think he will hurt himself, which would suck, and he would get no "money" after that.

p-l