Originally Posted by Zutroy
EC yes it is true that, your core is taken out of the equation. However, saying a blanket statement like that is false. If you build a strong core with other exercises, it's a moot point. Leg presses have a time and place like all other exercises, to make a blanket statement that they are useless is false.
This is continued from a challenge made to my Top 3 Exercises for Gate Starts post that also made it's way to the Thread Locked post. I stated that, outside of some injury related reason, that the leg press should never be used in an MTB specific strength training program. I made the "injury related" qualification because I do believe that a good strength coach should have the critical thinking skills to figure out where and how any tool could be used, even something as bad as the leg press or Smith machine (that should open up another can of worms).
However, unless an injury specifically calls for it, the leg press is a huge waste of valuable training time. In response to Zutroy's point above, what you suggest is physically impossible. You are able to expose your legs to a much higher intensity level (raw weight lifted) through the leg press than you can with just about any other exercise in the gym. Unless you are able to introduce the core to a load similar to that used in the leg press and have it practice the specific function of stabalizing that load, then the core will never be strong enough to handle the same load you have exposed your legs to.
This means that your legs will have the strength to produce a certain amount of force but will be unable to use it all on the bike because the core can not form a strong enough platform to display the strength from. You are only as strong as your weakest link, which is usually the cores ability to form a strong, stable platform. The only way to work on this specific function of the core is to expose it to that specific demand, which the leg press and "core specific" exercises do not. The only lower body exercises that do are the deadlift variations, squat variations and countless uni-lateral bodyweight and freeweight movements, making them the best choice if you are really interested in getting the biggest return on your training time investment.
Trying to build leg strength and core strength independantly of each other and then expect for them to optimally integrate on the bike is not backed by neither science, logic nor real world results. This is referred to as "Frankenstien" training since you are trying to "piece" your body together and is directly related to the bodybuilding mentality that pervades every corner of the strength and fitness industry. We are ultimately training movement patterns, not simply muscle groups, and until you approach training with this understanding you simply can not maximize your training time or riding potential.
Zutroy, I don't mean to be overly critical of your posts, but you did say that I was flat out wrong, and I truly do not believe that I am. I would greatly appreciate any backing that you might have for your position. I would very much like to discuss your point of view further if you would like, or even open it up to anyone else that has a question or some insight.