Getting to Know Your Joints Part 1 - Intro
Getting to Know Your Joints Part 1 - Intro.
The premise of these blog posts will be for me to explain the strucure and function of our joints. I also will provide details and video demonstrations describing the science behind several 'prehab' and strengthening exercises for different joints, enjoy!
How often do you think about the current health status of your joints? Whether you're an elite weightlifter, athlete, a regular gym-goer or a sedentary individual, an array of musculoskeletal misfortunes can pop up out of nowhere. Simply stated, joints are where two or more bones connect, but bone endings don't just link to one another like pieces to a puzzle. We rely on our ligaments to strongly connect our bones to other bones and we rely on tendons to connect our muscles to bones. Though highly important aspects, tendons and ligaments aren't the only structures that make up our joints. The internal framework of our bodies begins taking shape in about week four of fetal development. We grow tiny limb buds and during the sixth week, each limb bud continues to grow and elongate. During this process, high-collagen cartilage (hyaline cartilage) is laid down and solidifies to form bones. Another type of cartilage (articular cartilage) is also laid down where bones meet and functions to absorb shock and reduce friction between conjoining bones. Joint movement occurs when muscles pull (contract) across joints, moving one bone toward another. From explosive movements like sprinting and jumping all the way down to simple things like flexing a finger, all movement is made possible from joints. When we speak about joint health, we focus on range of motion, stability, flexibility, architecture and absence of pain. Joints become structurally compromised for a number of reasons. Some examples being injury, poor posture, incorrect exercise form, over-training, inflammation, genetics and inactivity.
Most, but not all joint injuries develop as a result of overuse and misuse. If you grew up living a very active lifestyle and continue to be vigorously active, it's nearly impossible to never experience some sort of injury. The reason being that each component of the musculoskeletal system has thresholds in terms of how much force and stretch can be tolerated. Unfortunately, the speed of athletic competition can often be too rapid for complete avoidance of accidents. Rapid change of direction, imprecise landing mechanics, poorly maintained playing fields \ surfaces and blows to the body are just a few examples of sport-related risk factors for joint injury. Injuries like SLAP tears, tennis elbow, golfers elbow, achilles tendonitis and ankle sprains etc. are all to familiar in the athletic population. Just enough to keep roughly 25,000 Athletic Trainers employed in the United States. Your body has more joints than bones and in several areas like your hands and feet each individual bone is part of one or two joints. It is important to understand that one small setback can have a lasting effect on joint function. For example, your rotator cuff muscles and tendons are what hold your shoulder joint in place and allow your shoulder and arm to move. If one of these muscles / tendons becomes irritated whether minor or major, the integrity and functioning of your shoulder joint will weaken and potentially never restore 100% functional health. If you have ever experienced some sort of sprain, strain or dislocation then you understand how long it takes and how much work is required to restore full function. Every injury is a big burden physically, mentally, emotionally and financially. But how can we prevent these injuries before they happen? The best solution would be for athletes and weightlifters to include some 'prehab' work in their programs. What is prehab? Prehab is the methodical approach of avoiding injury by improving strength, mobility, stability, balance (proprioception), core strength, joint function and posture. It is the realization that the internal deserves more attention than the external. Take a second to think about that. Why do we tend to only view exercise-related accomplishments as things we can physically see from the outside like weight loss and muscle bulk? Developing strong muscles is great but let’s take it a step further and consider how else we can gain & sustain physical wellbeing. An easy example of prehab would be spending time improving core strength to reduce the risk of back pain \ injury when doing your heavy lifts (squats, deadlifts).
Athletic injuries are not the only dangers that joints face. There is a large population of people that know all too well how joint pain can distress overall quality of life. According to the CDC, an estimated 54.4 million adults in the US have doctor-diagnosed arthritis (inflammation of joints), with a significantly higher prevalence in women than in men. There are over one hundred different forms of arthritis and it affects people of all age groups and walks of life. Unfortunately, certain forms like autoimmune disease 'rheumatoid arthritis' aren't entirely preventable. However, there are ways to be proactive and avoid, or at least delay the onset of such joint irritation. A study conducted by the CDC showed that the prevalence of arthritis among adults reporting no leisure time physical activity is significantly higher than the prevalence of arthritis among adults who do meet physical activity recommendations. Two major tips for avoidance are 1- Safe and effective physical activity maintenance and 2- Weight management. Carrying additional body weight damages cartilage and increases pressure on our weight-bearing joints like the knees and hips.
From a Strength & Conditioning standpoint we focus on Joint Stability & Joint Flexibility
- Joint Stability - Simply stated, the ability of a joint to resist dislocation. A stable joint will oppose irregular displacement of bones and will prevent injury to ligaments, muscles and tendons surrounding the joint.
Factors the effect joint stability
- Shape of Articulating bone surfaces - Some joints are more stable than others simply due to structure. For example, if you look at the top of your thigh bone (femoral head) you'll see that it's circular end fits very snug into the acetabulum (hip socket). Since the bone sits deep into a protective socket, the hip joint is relatively stable by design.
Your shoulder joint is one of the most mobile joints in your body. The humeral head fits into the shoulder socket like a golf ball on a tee, allowing for great range of motion but limited stability. The ball and socket design makes this joint very vulnerable for injury and other complications.
2. Arrangement of Ligaments and Muscles - For joints that are fairly unstable like the shoulder and knee, tension produced in ligaments and muscles make large contributions for keeping the joint held in place. When these tissues are weak, fatigued, overused or lax from being overstretched, joint stability is reduced. Strong muscles and ligaments can increase joint stability. For example, strength training the quadriceps and hamstrings increases stability of the knee.
3. Fascia integrity - Fascia, which I previously wrote a blog about https://olympiafitnessri.com/blog/the-fundamentals... is a fibrous connective tissue covering your internal framework. When fascia becomes locked up and tight, range of motion decreases and chances of injury and pain increases.
- Joint Flexibility - Range of motion allowed at a joint. Flexibility is joint-specific, a large degree of flexibility at one joint does not guarantee the same flexibility at all joints.
-Static flexibility - Range of motion present when a partner moves a body segment. Static flexibility provides us with better info regarding someone's joint tightness or laxity when suggesting someone's injury potential.
-Dynamic flexibility - Range of motion that can be achieved by moving a body segment via muscle contraction alone. Having good dynamic flexibility is significant in terms of achieving daily life tasks, work, or sport activities.
Factors that effect joint flexibility
- Shape of articulating bones and intervening muscle or fatty tissue - These segments may hinder movement at a joint's end range of motion.
- Laxity and\or extensibility of collagen and muscles crossing the joint - When collagenous tissues and muscles crossing a joint are not routinely stretched, they will shorten and flexibility diminishes. However, when they are routinely stretched, they lengthen and flexibility is increased.
- Proper warm-up - Lab studies have shown that joint range of motion increases slightly with temperature elevation.
- Hall, Susan J. (2007). Basic Biomechanics fifth edition. New York, NY: McGraw-Hill.
- Beachle, Thomas R.& Earle, Roger W. (2008). Essentials of Strength Training and Conditioning third edition. Denver, CO: Human Kinetics.
- Cartilage | Boundless Anatomy and Physiology. Structure, type and location of cartilage. Retrieved from https://courses.lumenlearning.com/boundless-ap/cha...