Muscle isolation is something that almost all who participate in weight training talk about. Those that are looking to tighten up or lose weight all have their “problem areas”. These spots are usually the thighs, stomach or arms. Those that are looking to gain muscle size attempt to isolate muscles in order to increase size. There is one problem with this... It doesn’t work!
Isolation is impossible in the exercise world although it is talked about as if it were a consistent theme. Focus on a certain muscle group is absolutely attainable and many times necessary in consideration to your goals. However, if you think you can truly isolate a muscle group, I hate to be the bearer of bad news.
You cannot isolate a muscle group because of how interrelated all of your muscles are. Not only does one run right into the next but they are all connected by this thing called fascia (the top picture). So when you are doing those extra 100 crunches in order to flatten your stomach out or the extra set of chest fly’s to help work on those pecks; you aren’t isolating. Whether it be extra work in order to tighten a muscle group or extra work for strength or size, don’t get mad when things aren’t working exactly like you expected. Biomechanically, these are two different ideas, so I will break them up and talk about them individually.
Muscle Tightening and Weight Loss
I can’t tell you how many clients tell me they want to do more ab work because they are upset with the muffin top, spare tire, etc that they have. This one always kills me because the common misconception that doing a bunch of crunches or sit ups will flatten out your stomach. They won’t.
Heres why, the muscles in your stomach region are only going to get so strong and hard. If you have a thick layer of fat on top of those muscles, you will never have a 6 pack or a flat stomach, it’s that simple. I don’t care if you have the strongest, hardest abs in the world, if you have that layer of fat on top no one will see or know. By doing a ton of crunches, that fat will not really be any more apt to fall off. What will take that layer of fat off? Weight loss, simple as that.
Lose the layer of soft stuff and then worry about the abs being hard and defined. Instead of doing the extra 100 crunches at the end of a workout, do some sort of intense cardio.
Muscle Size and Strength
Those of you that attempt to beef up a muscle group by “isolation work”, should read this. Granted a bunch of chest fly’s will effect the size and strength of your chest. But if you think you are isolating only the chest when you do a fly, your wrong. No matter what you are doing, other muscles are coming into play. Bicep curls? Your forearms are getting worked. Tricep Pushdowns? Your deltoids, rhomboids and forearms are getting some work. Now, this isn’t a bad thing that your other muscles are getting play as well. In fact its a good thing, there’s over 200 muscles in your body, think about how many you focus on during exercise. Maybe 10-15. Sure you do back, chest, legs, calves, biceps... How about the supraspinatis or serratus? Ever focus on training those?
Okay, at this point you may be saying so what it still works. True it does work, just stop calling it isolation ;-).
A better way yo target your muscle groups is be a pre and post exhaustion technique. This is done by tiring out the synergists of a muscle before or after working that muscle. So, if you are trying to really attack your chest, do a fair bit of bicep work right before or right after a chest set.
For example, do either a few sets of triceps before even getting into a bench or incline press, or do one set of triceps before each set of chest. For back, you can wear out your biceps before getting into lat pulldowns or pull ups.
This works by fatiguing the synergist muscles, forcing the agonist into more work. It is about the closest you can get to actually isolating a muscle group.