Today one of the hottest words in the fitness industry is CORE. What is the core? How do you correctly train the core? And, why is core training important to athletic performance? The following article will attempt to answer these and many other questions on the core.
The core is where the body’s center of gravity is located, and it is where movement begins. In standing, the body’s center of gravity is located approximately two inches below the navel. Because all movement begins at the core and then progresses out to the arms and legs, core strength is essential. This is why coaches emphasize watching your opponent’s navel while playing defense.
Many of the major muscles of your shoulders, arms and legs are attached to the pelvic bones and/or the spine, the core. Greater core strength increases the stability of the pelvis and spine and improves body control or balance during athletic movements. This helps the athlete generate greater power, not only from the core muscles, but also from the shoulder, arm and leg muscles because they are anchored to the core. If your core muscles are well conditioned, you will enjoy optimal transfer of energy from large muscles to small muscles when you run, jump, twist, lift, throw, and perform other movements in your sport. Based on this it is essential to develop core strength before arm and leg strength.
Anatomically, the core consists of the muscles of the hips, abdomen, and low back. These trunk muscles can be further divided into two categories: (1) Global muscle system and (2) Local muscle system. The global muscle system is the large, force producing muscles (rectus abdominis, internal and external obliques and back extensors). These are the muscles we usually train during exercise programs. The local muscle system is the deep small muscles (transverse abdominis and the multifidus).
The transverse abdominis and the multifidus have a unique function because they are the first to activate in the core, even before movement occurs. For this reason core training must begin with these muscles. Precise contraction of the transverse abdominis and multifidus must be gained independent of the global core muscles.
How do you know if you need to train your local abdominal muscle system? Try these two tests. The abdominal drawing-in test: Lay on your stomach. Place a blood pressure cuff under your stomach so your navel is in the middle. Pump up the cuff to 70mmHg and allow it to stabilize as you are laying on it. Breathe in then out once. Immediately after you breathe out, pull your navel slowly inward toward your spine. Resume normally breathing as you keep your navel pulled in. The blood pressure cuff should drop 10mmHg (reading should now be 60mmHg).
You have good strength if you are able to keep the gauge at 60mmHg while breathing regularly for ten seconds and NOT allowing your back or hips move. If the gauge drops less than 10mmHg or if your back and hips move, your transverse abdominis is weak. If the pressure increases above 70mmHg this may indicate you are using improper global muscles, rectus abdominis for this test. The endurance of the musculature can also be assessed by repeating the ten second holds ten times. If you are unable to complete any part of this test begin your training program here (1).
(1) Lay on your stomach with blood pressure cuff under stomach 70mmHg (2) Draw your navel in toward your spine (3) Look for a 10mmHg drop to 60mmHg (4) Breathing “normally” for 10 seconds while maintaining drawn in navel (5) Rest 10 seconds and repeat 10 times.
Leg loading test / exercise: Lay on your back with your knees bent. Place a blood pressure cuff under your low back / tail bone area. Inflate the blood pressure cuff to 40mmHg. Tighten the pelvic floor muscles by imagining you are slowing the flow of urine and then perform the navel draw in as above. Watch the pressure change and hold this contraction. The pressure should remain at this level. Now progress the test through these phases:
(1) Slide your left heel along the floor. Return to the start position. Slide your right
heel along the floor. Return to start. Alternate left and right legs for a total of 40 repetitions.
(2) Straighten your left knee out with your foot about 12 inches off the ground (right foot remains on the ground). Keep the pressure reading at 40mmHg (NO INCREASE OR DECREASE). Return to the start and perform with the right leg. Alternate left and right legs for a total of 20 repetitions.
(3) Bring both knees up toward your chest. Set the blood pressure cuff at 40mmHg. Activate the pelvic floor muscles and draw in the navel. Slowly straighten the left leg out not allowing the pressure to change. Bring the left knee in and then slowly straighten the right knee out, maintaining the same pressure. There will be a tendency for the pressure to increase as you move your leg out. Contract your local core muscles to prevent this increase in pressure. Repeat 20 times on each leg.
Proper core training can improve all aspects of athletic performance and reduce the risk of injury. For greatest success begin working the local core muscles first and progress to the global core muscles. Next we will discuss how to train the anti-extension core muscles. Start here so you will be prepared for the next phase!