I think you should read this before assuming that flat-ground work is necessary. I just want to make sure we get both sides of the argument regarding flat-ground work.
This is the thinking by the flat ground throwing advocates: "You will throw harder off a mound because you are helped with acceleration from the decline, but as far as building arm strength and quickness the mound is not the way to go."
The idea here I don't believe makes much sense—to not do the only thing that can possibly make a pitcher more effective and more successful at getting hitters out…throwing from the mound at game intensity. That is how a pitcher will ultimately build his body so he has the capability to pitch deeper into games at full intensity. There is no other place to duplicate that than throwing from the mound. You just can't get it throwing from flat ground…even long toss.
In the effort to save the arm the pitcher prevents himself from getting better since pitching mechanics on flat ground are completely different than pitching mechanics throwing from the mound. The pitchers weight shift and weight transfer is different therefor his stride length on flat ground will be shorter. Because his stride is shorter his front leg will not stay flexed as long which will adveresely effect his ability to rotate his trunk properly. And because his stride is shorter his arm will not get into the correct throwing position. Trunk flexion position will also be different because the trunk will be more upright at ball release than while throwing from the mound.
Because everything is so different while throwing on flat ground then a bullpen thrown on flat ground or mechanics work on flatground will not transfer to throwing from the mound. A pitchers control or command of pitchers will also be different because his release point will also be different. The two activities are completely different and the pitcher's body will interpet them as completely different. This means that a pitcher who throws on flat ground will not get better for throwing from the mound.
For pitchers who have control problems no amount of flat ground throwing is going to help them get better for games because they are two completely different mechanical activities. If pitchers want to improve their mechanics, their control and their velocity they should follow the sports science Principle of Specificity which says that whatever activity you want to perform better at…in this case throwing from the mound in a game…you had better do it as closely as possible to the activity you will perform in game competition.
The pitcher's body must be conditioned to throw a certain number of pitches in game competition. For his body to be fully conditioned to throw downhill at game intensity it would not seem to make sense to not do that activity which is the only way possible to become better conditioned for game throwing.
No other sport that I know of has uses this type of training methodology to help an athlete get better. I know of no sport where athletes save themselves for the game. Their practices are as game specific as possible in order to get better for the next game. Pitching from the mound is about acceleration and deceleration. A pitcher's body must fully be trained to do both of those things at full game intensity if that is what he is expected to do in a game.
Could it be that the idea of saving the pitcher's arm by doing activities at less than game intensity or throwing on flat ground instead of the mound is one of the many reasons that pitchers are becoming injured more often…and why they cannot go deeper into games? It might be something that baseball should address since I do not see pitching getting any better with all the new training methodologies out there.
We seem to forget that pitching is a specific skill—a simple "two phase" movement that to be mastered must be done with proper mechanics as specifically as possible a lot of the time.. And throwing from the mound at game intensity is the most specific activity that a pitcher can do to get better at hitting the glove, perfecting his pitches and ultimately being more effective making hitters more uncomfortable than they currently seem to be.
Playing catch on flat ground is certainly an activity that pitchers do regularly. However the idea that we should save pitchers by having them throw a bullpen on flatground is not going to help them improve for games or make them more successful.
Source:
http://www.pitching.com/blog/43/shoudnt-we-begin-to-que...-pitching-absolutes/