What TPI is all about

Mobility is the combination of normal joint range of motion and proper muscular flexibility. This is a must for proper mechanics and for injury prevention. Mobility allows the body to move in all six degrees of freedom, therefore giving the ability to perform any motion – without having to sacrifice stability! Mobility allows the generation of elastic energy between muscles, and therefore establishes a base for efficient power production.
Stretch-Shorten Cycle: "A common pattern of muscle activation, particularly during high performance tasks, is to use and eccentric-concentric sequence in which the active muscle is first lengthened and then shortened.  The advantage of this pattern is the muscle being able to perform more positive work if it is actively stretch before being allowed to shorten." - Neuromechanical Basis of Kinesiology, Roger Enoka

The 3 Rules of Engagement - allowing the stretch-shorten cycle to be most effective:
1. No Time Delay

2. Moderate Stretch

3. Faster Stretch = More Energy” 

Stability is the ability of any system to remain unchanged or aligned in the presence of change or outside forces. That is a good summary of what many areas in our body that are defined as stabilizers (such as the lumbar spine) are asked to do.
Stability is created by combining three things:

1. Balance

2. Strength

3. Muscular Endurance

If you want to keep the bow of a bow and arrow stable as you pull the string back, you must have good balance, strength, and muscular endurance. This is the same principle involved in creating a powerful golf swing. The ability to keep one part of the body secure while stretching and contracting adjacent segments, allows us to generate speed and maintain a consistent posture throughout the golf swing. That is Stability. 

 "The body works in an alternating pattern of stable segments connected by mobile joints.  If this pattern is altered- dysfunction and compensation WILL occur." - TPIs Mike Boyle and Gray Cook

 NORMAL PATTERN

Foot                                                 Stable

Ankle                                               Mobile

Knee                                                Stable

Hip                                                   Mobile

Pelvis/Sacrum/Lumbar Spine     Stable

Thoracic Spine                               Mobile

Scapulo-Thoracic                           Stable

Gleno-humeral/Shoulder            Mobile

Elbow                                               Stable

Wrist                                                Mobile

Cervical Spine                                 Stable 

You can see how this observation of an alternating pattern of mobility and stability can help describe how injuries occur. If you take the lower back as an example, you will often find that the hip joints and thoracic spine are limited in mobility.  Unfortunately, limited thoracic spine and hip mobility are two of the most common findings in male golfers. This may be why lower back injuries are so common in golf.
What can alter a normal pattern?
1. Traumas - Accidents, Posture, Repetitive Injuries.

2. Thoughts - Stress, Anxiety, Mental Collapse.

3. Toxins - What You Eat, What You Breathe, What You Drink.

4. Technique - Poor Learned Skills, Muscle Patterns 

 Muscle imbalances are caused by a sedentary lifestyle; a lack of variable movements or prolonged static postural stress due to sitting, standing, walking in a straight line. Overuse leads to shortening/tightening (not spasm) of postural muscles. Disuse leads to weakening/inhibition of phasic muscles.

EXTREMELY COMMON EXAMPLES IN GOLFERS:

LOWER CROSSED SYNDROME
Dr. Vladamir Janda, a physician from the Czech Republic, was really the first person to document this type of muscle imbalance. Dr. Janda noticed that many people developed a distinct pattern of muscle imbalances due to prolonged static postures, such as sitting at a desk all day. For example, if you sit in a chair for eight hours a day, in time, your hip flexors will become shortened or tight. Your brain will automatically start to shut down or inhibit your glute muscles (butt) which are on the opposite side. Since your glute muscles are not working properly, your body will recruit synergistic muscles such as the hamstrings and lower back muscles to assist the glutes in performing hip extension. In other words, you start to recruit muscles that were not intended to be used for specific actions such as walking and especially, golf.
The most common pattern of imbalance that Dr. Janda observed he named the Lower Crossed Syndrome. It is primarily the combination of tight hip flexors and a tight lower back, paired with weak abdominals and weak glutes. This combination leads to an excessive arching or rounding of the lower back, a flabby or protruding abdomen, and a flat butt due to weakness in the glutes. This is a very dangerous combination of muscle imbalances due to the excessive stress that it places on the structures of the lower back.

UPPER CROSSED SYNDROME
The muscle imbalances seen in the following C-Posture illustration are collectively called an Upper Crossed Syndrome. The term, Upper Crossed, was also coined by Dr. Vladimir Janda. Dr. Janda noticed the same pattern of muscle imbalances on so many people that he started calling the pattern an Upper Crossed Syndrome.The most significant joint restriction seen in the C-Posture is the lack of thoracic spine extension (limited backward bend or arching of the upper back). This can make it almost impossible to eliminate the C-Posture. Lack of T-Spine extension can lead to a severe loss of spinal rotation, which in turn, will limit the ability to create a good backswing turn.
 

 Have you ever wondered how someone such as Jim Furyk won the U.S. Open with that golf swing? Or have you wondered how players such as Raymond Floyd or John Daly have had such successful careers with such unorthodox golf swings? Fortunately, with the aid of 3D motion capture systems, researchers have been able to identify the true measurement of a good golf swing. The answer is not in how close your swing resembles Rory Mcllroy or Jason Day on a video camera, the answer is in the efficiency of your swing compared to the best players in the world. In other words, there are a lot of ugly golf swings on the PGA TOUR but they all seem to get the job done. The question you should be asking yourself is “How can I make my golf swing get the job done?"
Using data collected from 3D motion analysis systems, we can look at how golfers generate speed and transfer the speed or energy throughout their bodies. We have found the most efficient sequence of how they transfer this speed to the club head. We call this the “kinematic sequence.” The amazing thing is that all great ball strikers have a remarkably similar kinematic sequence of generating speed and transferring speed throughout their bodies. That means if you compare Ernie El’s kinematic sequence to Jim Furyk’s kinematic sequence, it’s hard to show a difference. That is a bold statement since there is such an obvious difference on 2D video. All great ball strikers begin by generating speed from their lower body and transferring that speed through their torso, then into their arms, and then into the club. But what swing style they use to complete this sequence is completely unique to each player.