Human joints

In my last blog, I focused on the importance of upper body strength training for runners. As important as upper body strength is for proper stability and prevention of injury, flexibility in this region is of equal, if not, greater importance in the prevention of injury. In order to properly discuss the importance of joint flexibility, my post today will attempt to provide you with a brief and elementary explanation of structure and function of human joints.

Every joint has a total angle of motion unique to the design of the articulating surfaces of the heads of the bones coming together to make up the joint. The only limiting factor in joint motion is the flexibility of both connective tissues and muscles of this region.

Muscle usually crosses a joint and connects to the bone by connective tissues referred to as tendons. Tendons consist of numerous layers of fascial tissue that provide the sheathing for every muscle fiber that makes up the muscle. They exit at the ends of each bundle of fibers becoming tendon, crossing the articular surfaces of the joint, and eventually merging with the tissue making up the sheathing over the surface of the bone called periosteum. During fetal development, all these connections are formed and is the reason injury to one select region can effect the whole body.

Connective tissue also is the material making up the both the ligaments and capsule surrounding most joints. The ligaments are strong reinforced bands within the structure of the capsule, which provide increased stability in all regions of increased stress during joint movement. The capsule provides not only additional stability to the joint, but also its inner membrane secretes the synovial fluid that provides both lubrication and nutrition to the slick surface cartilage covering the heads of the bone. In order for this fluid secretion to occur  providing flow over these surfaces, motion in the joint must occur.

I would like you to imagine the surface of a pond as my example to explain this motion. When the surface is calm and there are no ripples, it quickly becomes clogged with algae and other contaminants. However, when there is wind causing ripples on the surface, movement is occurring, and the pond remains fresh and clean due to the algae and contaminants not having the necessary stagnant environment in which to grow. All fluids in the human body react in the same way, and must have frequent periods of motion throughout the day to avoid the potential for chemical reactions that cause fluids to thicken and allow build up of contaminants to occur. Also like the function of a sponge, contaminants are squeezed out, and clean fluids taken in, by the effect of pressure on these tissues,

Flexibility exercises are one of the most important ways to provide this motion and limit loss of motion within the joints.

SHOULD RUNNERS STRENGTH TRAIN?

While on my early morning bike ride early this morning, I passed numerous runners out on the roads. It reminded of how I enjoyed taking an early morning long run and then ending up down at the beach or a nice park to watch the sunrise. I would have continued to include running as part of my fitness routine along with cycling and strength training, but, unfortunately, I had to stop running secondary to knee problems. I, of course, replaced the running routine with cycling, inline skating, the elliptical cross-trainer, for continued cardio improvement, but still miss the exhilaration of running.

In order for your body to withstand the rigors of long distance running, a strong upper body is needed along with strong legs. The muscles of the neck have the combined job of stabilizing the weight of the head on the neck and holding the shoulder girdle (the shoulder blades and the collarbone) in position.  Strong shoulders are required to hold and support the weight of the arms and hold the head of the humerus in place on the shoulder blades, and still allow the proper rhythmic arm swing over a long duration of time. The core muscles, which I have discussed in previous blogs, function to hold the pelvic girdle in proper alignment to prevent increased risk of injury to the lumbar spine.

Everyone of these muscle groups is being brought into play to combat the excessive forces created by the downward pull of gravity, arm weight, and force of impact each time your feet strike the running surface. It is this for this reason that a runner who is looking to run injury free over the duration of his lifetime, include an efficient upper body strengthening program into his wellness program.

Back extensors

So far I have described the structure and function of the four muscles of the abdominal group, but there are other muscles that attach to, and provide stability, for both the lumbar spine and pelvis. The next group of muscles I would like to discuss are called the lumbar extensors or lower back muscles.

As I mentioned previously, the abdominal muscles are connected to each other, and also the bones of the skeleton, by strong connective tissue known as fascia. The strongest sheet being the thoracolumbar fascia that attaches the oblique muscles to the lumbar spine, bottom of the rib cage, and the top of the pelvic girdle. Its structure consists of numerous layers whose fibers run in opposing diagonal patterns to provide stability to the trunk region, to not only provide the strength to resist the outward pressure exerted by the contents of the abdominal cavity, but also the contractions of the numerous muscles.

The back extensors are strong bundles of muscles that attach to the top of the posterior pelvic girdle and run up the lower back, middle, upper back, neck, and connect to the bottom of the posterior skull. The strongest groups of these muscles are the ones that span the length of the lumbar spine and are encapsulated between the strong sheets of tissue of thoracolumbar fascia. This fascia holds these muscles in place and allows them to perform the function of lumbar extension. They create an upward pull on the posterior portion of the pelvic girdle, neutralizing the upward pull exerted on the anterior portion of the pelvis by the abdominal group, and providing lumbar stability and prevention of excessive torque and risk of injury to the lumbar spine.

The best exercises for isolating and strengthening this muscle group, are called back or trunk extension exercises, and I will provide a video in the next few days in the training tips section on the home page demonstrating these. 

Elliptical Crosstrainer

After a fast paced 25 mile bike ride yesterday morning, I decided to perform the cardio segment of my workout on my elliptical cross-trainer. I feel very fortunate to own the Octane Q35 and have been using it to balance out my workouts ever since my running days ended secondary to knee problems. I  highly recommend the elliptical equipment to anyone looking for a no-impact exercise that closely mimics the bodies natural gait pattern.

Many of the more high-end machines, such as the Octane, offer a varied selection of fitness programs. They come with electronic panels that contain the necessary software that offer you the option of selecting an array of challenging workout routines. They can range from a slow jog around the 1/4 mile track, interval and hill training, and with the addition of a polar heart rate transmitter you have the option to monitor your heart rate during these workouts. Although many have heart rate sensors built into the stationary handles, I recommend using a chest strap with a polar transmitter to allow you to use the moveable handles. The moveable handles on the machine allow you to include the upper body into the routine and also force the core muscles to work harder to maintain proper dynamic balance and coordination.

To motivate yourself, and eliminate the boredom factor, it is wise to place the equipment in a convenient location where you can watch TV or listen to music. I have mine placed in my bedroom and perform my workout while watching movies on my TV or laptop computer.

Transversus Abdominus

 

The last muscles to make up the four muscles of the abdominal group, are called the Transversus Abdominus. It's the deepest layer of the four muscles, with fibers that run in a horizontal plane along either side of the trunk connecting to fascia of the lumbar region in back to fascia of the Rectus Abdominus in the front of the body. The main function of this muscle is to provide lumbar spinal stability through compression of the contents of the abdominal cavity during concentric (or shortening) contraction. Think of this muscle as providing a belt that connects to the lumbar spine to the Rectus Abdominus muscles. The exercise that best isolates this muscle for strengthening is called the posterior pelvic tilt which I explain in greater detail in this short video which you can access by clicking here..

Connective Tissue

I realized this morning that although I have described three out of the four muscles of the abdominal group, I forgot to mention one of the most important materials to allow muscles to provide their proper function: The connective tissues.
In the case of the abdominals, the type of connective tissue is called fascia, and its main function is to provide a muscle attachment point to the other muscles and also the bones of the trunk, hip, and lumbar spine. Its structure consists of strong collagen fibers with minimal elastic properties, secondary to having to stabilize the lumbar spine and prevent increased torque that could increase the risk of injury. It connects the muscles of the rectus abdominus to the lower ribs, upper pelvis, and also the oblique muscles. The obliques then connect posteriorly to a large fascial sheath called the thoracolumbar fascia which encapsulates the strong extensors of the lumbar spine and attaches to the lumbar spine. Upon contraction of these muscles, their fascial attachments tighten and distribute the force over the joints leading to motion.
Core stabilization and strengthening exercises not only strengthen the muscles, but also the fascial connections, and should always be a part of well rounded fitness routine.

Importance of deceleration muscles in cycling

While riding my bike yesterday, I started to think of the role that the muscles of my lower body play in proper safe and efficient cycling form. Muscles work in two phases of contraction, and they are:
·    Concentric or shortening phase of the muscle under load
·    Eccentric or lengthening of the muscle under load
Since the physiology of the muscle restricts it to active shortening, it can only lengthen while under an imposed load. This load can be from gravity, resistance, or increased  speed of motion.
Many of us realize that when cycling, the power stroke is the motion generated from the highest to the lowest point n the first 180 deg. of the pedal revolution. The main muscles providing this active contraction are the hip extensors, quadriceps, and the plantar flexor (plantar flexion is pointing the toes) muscles of the ankle. All are concentrically firing at once to move the pedal downward and generate increased torque required to move the bike forward. But let me bring your attention to what I feel is the most important function, and that is the role of opposing muscle groups in injury prevention. The hip flexors, hamstrings, and, ankle dorsi flexors (dorsiflexion is lifting of the toes) all come into play to provide progressive deceleration of the downward motion to prevent injury to the joint and allow for a smooth transition into the next power stroke. There must be ample time for this deceleration phase, and is just another great reason of why it is so important to maintain good flexibility, secondary to a tight muscle not allowing the needed deceleration time to avoid increased the risk for tearing of the tissue.
As a Beachbody Coach I realize this, so every one of our unique fitness DVD's offer the proper pre-exercise and post-exercise stretching routines to increase flexibility and prevent injury. Not in the program you're performing, but in every aspect of your physical lifestyle. Check out the offerings by "clicking here" and clicking on the Shop tab.  

Oblique Muscles

In a recent post, I discussed the structure and function of the Rectus Abdominus muscle which is one of the four groups of muscles that makeup the abdominal group. These muscles are arranged in four layers from superficial to deep, with the Rectus Abdominus group being the superficial of the group.
The next two layers of the abdominal group are called the Obliques secondary to the diagonal orientation of their muscle fibers. They consist of the following:  

External Oblique (Second Layer)
•    The muscle fibers of the external oblique are oriented to run diagonally on the side from posterior (back) on the rib cage to anterior (front) on the pelvis.
Internal Oblique (Third Layer) 
•    The muscle fibers of the internal oblique are oriented to run diagonally on the side from anterior on the rib cage to posterior on the pelvis.

Both muscles function to provide spinal stabilization and trunk movement. Due to the unique orientation of their fibers and their overlapping locations to one another (think of the design of the belts of a radial tire) they provide the following trunk movements.
o    When all contract simultaneously on both sides they provide stabilization to the trunk by neutralization of trunk rotation and allow the rectus abdominus to function in   moving the pelvis toward the bottom of the rib cage.
o    If one external on one side contracts with the internal on the opposite side then rotation to the side of the internal oblique occurs
o    If both the external and internal oblique on the same side contract, then trunk side bending to that side occurs.

As a valued segment of the core musculature their main function is to stabilize the pelvis and thus prevent excessive torque on the lumbar spine.

P90X Results and Recovery Formula

 

This is a video of me blending up a P90X Results and Recovery Formula for replenishment of energy stores after a workout. This is one of the many fine products offered by Team Beachbody Company of which I hold the status as an Independent Team Beachbody Coach. For more detailed information please click on "Team Beachbody" for access to my personal website and click on the shop tab. 

Recent fall

Recently while taking an early morning bike ride I took a nasty fall, and I feel if it weren't for my understanding of Biomechanical principles and varied experience in martial arts, I would have suffered serious injury. Although I live in Naples, FL, and the elevation is at almost sea level, I own a mountain bike secondary to its strong construction and its unique ability to go off road to avoid obstacles, traffic, and the resulting wheel damage that often happens  with the expensive racing bikes. I was coming up to an area that was under construction and was riding in loose dirt. As I was getting ready to unweight the front wheel and jump the curb, I noticed the exposed curb footing and was unable to lift the tire high enough to clear the curb and get on the sidewalk. My tire hit the upper portion of the curb quickly jerking the steering wheel to the right and pitching me to the left and over the handlebars. I immediately tucked my left shoulder and rolled with the fall and quickly found myself back on my feet. I had practiced this same fall many times when studying Judo other martial arts forms. So if this was a knee-jerk-reaction from years of martial arts  training, then why do I state the principles of Biomechanics saved me? Because I was able to change my linear motion (motion in a straight line which probably would have resulted in some serious road-rash) into angular motion and redirect the force to a small portion of the back of my shoulder. If I had pitched forward onto my hands and face I probably would have sustained serious injury to my palms, forearms, elbows, chest, face, knees, etc. To apply these principles to strength training notice how an exercise machine (such as Cybex or Nautilus) changes the vertical direction of the weight stack into angular motion for the select joints and muscles of the body to provide safe, efficient motion reducing the "sticking point" that must be overcome with the lifting of free weights.

Rectus Abdominus muscle

Pictured above is the Rectus Abdominus muscles which makeup one segment of the four muscles of the abdominal group. The Rectus Abdominus muscles are the muscles most often referred to as the "six pack" (there are eight sections, but there are only six exposed) or "rock hard abs" in the fitness commercials. These muscles have fibers that run in a vertical direction and have attachments to the bottom of the ribcage, top of the pelvic girdle, and the internal and external oblique muscles on each side of the body. This vertical orientation of force lifts and holds the pelvis in position and reduces the load on the lumbar vertebrae. When this muscle group is weak the pelvic dips downward, thus creating excessive curvature in the lumbar spine. This in turn results in increased force on the back or posterior joints of the lumbar vertebrae. Demonstrating the importance of core training exercising for achieving strong muscle tone in these muscles.

Adaptation: GAS Principle