What are Core Muscles and Why are they Important?
Functionally and anatomically these muscles can be divided into two sections:
- Deep stabilization system
- Superficial movement system
Anatomically, the muscles that are deeper in the body work more to stabilize the pelvis and spine, and the muscles that are located more superficially are more important for moving the pelvis and spine.
1) Deep Stabilization System
Core Training places a lot of emphasis on working the deep muscles of the core. Research shows that the deep muscles contract first before any movement is initiated. The body is pretty smart! It is wired to be stable first before it engages action.
The deep muscles are close to the spine and pelvis and they can help to move the body, but their primary role is to stabilize the pelvis and lower back. This protects these areas and gives you a strong foundation for the upcoming activity.
The core muscles that make the deep stabilization system are:
The transversus abdominus is one of the most important core muscles. From the back it wraps around the torso, the top of the pelvis and attaches to the pubic bone and fascia in the front. It compresses the abdominal contents, thus adding stability to the lower back and pelvis.
The lumbar multifidus runs on an angle from the sides of the vertebrae to the tips of the vertebrae. Because it runs on an angle it helps with rotational stability. Research shows that people with chronic lower back pain have significant atrophy (wasting away) of the multifidus.
The pelvic floor muscles connect the sacrum and pelvis to the pubic bone. Their primary job is to stabilize the bottom of the abdominal cavity. The pelvis floor works with the transversus abdominus and multifidus to stabilize the pelvis. Kegel exercises are a great way to strengthen the pelvic floor muscles.
The diaphragm is the main respiratory muscle. But since it attaches to the ribs and spine it can help to stabilize the spine. The diaphragm also forms the roof of the abdominal cavity, so it stabilizes the top of the abdominal cavity.
The internal oblique is the deeper of the 2 oblique muscles. It runs on an angle from the pelvis up to the ribs. Its primary role is in stabilizing the core, but it also helps to move the spine.
The transversospinalis muscles run from the transverse processes (sides of the vertebrae) to the spinous processes (tips of the vertebrae). The multifidus, semispinalis and rotators are included in this group. All of these muscles focus on segmental stability of the spine because they span just a few vertebrae in length. These muscles are also important for rotational stability.
All of the deep core muscles are important. When you perform exercises that require your spine to be stable, you challenge these core muscles. The plank exercise, bridges, alternate arm and leg raises, and the drawing in maneuver are examples of exercises that can increase core stability.
Equipment such as the Pineapple Whole Body Vibration System, the bosu ball, wobble board, or an exercise ball can increase how much the deep core muscles work during exercises. Any exercise or piece of equipment that requires your muscles to work harder to keep your spine stable will increase the muscle work in the deep stabilization system of the core.
2) Superficial Movement System
Core training focuses on pelvic stability. When the pelvis moves, the hips move, and when the pelvis moves, the lower back moves. If the pelvis is stable, the lower back and hip are stable, so any muscle that attaches to the pelvis is part of the core as well.
The latissimus dorsi (lats), which helps you do pull ups, is most often thought of as a back and shoulder muscle, but it also attaches to the pelvis, lumbar vertebrae, thoracic vertebrae, and ribs. The lats can help to tilt the pelvis forwards or to the side, and it can negatively affect lower back posture when tight and inflexible.
The erector spinae are the group of muscles that people most commonly think of when they talk about lower back muscles. They are a group of superficial muscles that run the entire length of the spine. As the name suggests, these muscles help to keep the spine erect and they also pull the spine backwards. Every lower back exercise will place some emphasis on the erector spinae muscles.
The iliopsoas is the main hip flexor muscle. It attaches to the front of the lumbar spine and pelvis. It is primarily responsible for bending the hip, but it can also help to stabilize the pelvis, lower back, and hip.
The adductors are the muscles of the inner thigh. Most people don't think of the inner thigh muscles as core muscles, but all of the adductor muscles attach to the pubic bone, which is the front part of the pelvis. Because they attach to the pubic bone they can help to stabilize the pelvis, especially when standing on 1 leg.
The hip abductors (gluteus medius and minimus) also attach to the pelvis. The gluteus medius and minimus are very important for hip stability, and they are especially important for stabilizing the hip and pelvis when standing on one leg. This is one of the reasons I say that balance exercises are so important in core training.
The hamstrings are the muscles on the back of the thigh, and they attach to the bottom of the pelvis. Strong hamstrings can help to anchor and stabilize the pelvis, and tight inflexible hamstrings can pull on the pelvis and negatively affect lower back posture.
The gluteus maximus is the largest muscle in the body and it attaches to the back of the pelvis. It extends thigh at the hip, and assists in laterally rotating the thigh. It works with the hamstrings to move the pelvis and also helps to stabilize the pelvis. Bridges can be considered a core exercise because it works the glutes while keeping the spine stable.
The external obliques attach to the ribs and pelvis but they are located superficially compared to the internal obliques. The external obliques are designed slightly more for moving the spine than stabilizing, but the external obliques do also help to stabilize the pelvis and lower back.
The rectus abdominus (6 pack) is probably the most popular core muscle. It runs down the front of the spine, and it is the main muscle for flexing and bending the. It is the main muscle for core exercises such as crunches and sit-ups.
What are the benefits of core strength training to the athlete?
- Greater efficiency of movement (increased Range of Motion)
- Improved body control and balance
- Increased power output from both the core musculature and peripheral muscles such as the shoulders, arms and legs
- Helps to reduce the potential for training and sports injuries
- Improved balance and stability
- Improved athletic performance