One thing that I learned in my weight lifting journey is that isolating muscles can be effective, but only if you're properly working all the muscles in that group at the same rate. For instance with the shoulder:
You might have a couple different machines that you work on to target two different muscles. At some point they will grow ahead and become more powerful than some of the other muscles in the shoulder that have not received attention. At that point the body will stop or slow down muscle growth on the muscles you are working because it realizes it's out of balance. Having a weak muscle in the midst of a couple well-worked ones will eventually cause injury.
Instead of working on machines that isolate muscles, I now do only core lifting. Core lifting essentially forces the body to use an entire group of muscles together which allows them to grow together and that ultimately leads to healthy development. When I switched to core-type lifting (i.e. pull-ups instead of 5 different machines to target all those muscles) I noticed a huge difference in my muscle growth. |