Abdominal Musculature Breakdown and Functions

The abdominals are composed of the rectus abdominis and the lateral abdominal muscles known as the transversus abdominis, and the internal and external obliques. The rectus abdominis runs from your sternum to your pelvis and essentially helps pull your rib cage and your pelvis closer together. The transversus abdominis acts as a natural weight belt essentially holding your insides in, and stabilizing your trunk. The internal and external obliques work to rotate the torso and stabilize the abdomen. The rectus abdominis is the actual visible “six pack” that you see in someone with well-developed abs and a low body fat percentage. However, the lateral abdominal muscles are also very important to develop due to their role in supporting the spine and maintaining a healthy lower back. In addition, developing the transversus abdominis helps pull your stomach area inward giving you the appearance of a smaller waist. Whenever you suck your stomach in (like a guy at the beach trying to hide his gut), you are using the transversus abdominis to perform that movement.

The action of the rectus abdominis can be initiated by crunching the upper body up or by crunching the lower body up. A popular myth is that people think that the upper abs and lower abs can be worked separately. The fact is that you cannot isolate the upper or lower
abs. The rectus abdominus is one muscle group and the entire length of the muscle group is activated whether you’re pulling the upper body up or pulling the lower body up. With that said, it should be noted that it is beneficial for you to work the abs from a variety of different angles to ensure maximum muscle fiber development throughout the entire abdominal region.

RELATIVE LEANNESS OR BODY FAT %

When people ask me how to go about getting six-pack abs, they usually start talking about all of the crunches and other exercises they spend hours every week performing without seeing any tangible results. My first response is that they most likely already have a reasonably developed set of abdominals if they’ve been training for some time. Their abs are just covered by excess body fat. That is really what people are inadvertently asking me when they ask what they need to do to get visible abs; what they really need to focus on is reducing their body fat.
Granted, a certain level of muscular development of the abs is necessary to have a ripped “six pack” appearance, but ultimately your body fat % is what’s most important. Generally, men need to get below 10-11% body fat to really start to see the abs (they really pop out at 7-8%), and women need to get below 16-19% body fat to really bring out their abs. However, everyone will differ depending on his or her body fat distribution. Based on individual body fat distribution, some people may need to get even leaner than these percentages to be able to see their abs.
Men tend to accumulate more body fat in the abdominal area, whereas women tend to accumulate more body fat in the hips and thighs. If you want to figure out how much body fat you need to lose to get down to these levels or lower, you’ll need to have your body fat percentage measured. There are many methods available to do this, but the methods that will be most accessible to the majority of people are the skinfold caliper method, the bioelectrical impedance method, or estimates using girth measurements of various body part circumferences. If you’re a member at a gym, you can most likely have a trainer at the gym perform either the skinfold caliper method or the bioelectrical impedance method. Some of the calculations and tables for the girth measurement method can be found on-line or your trainer at your gym may be able to complete the calculations if they have the tables available.
While this manual will provide all of the information you need to know about developing your abdominals to the greatest extent possible given your genetics, the majority of this manual is going to focus on proven strategies and tips that will help you reduce your bodyfat to such levels that your abdominals are clearly visible.