ct

What is this

● CT structures include bones, tendons, ligaments, fascia, and cartilage

● Adaptations in CT resulting from training are critical for how muscle force is transmitted to bone, joint stability, and injury prevention

● CT adaptations take place at a slower rate compared to skeletal muscle.

CONNECTIVE TISSUE

Terms under STIMULI FOR CONNECTIVE TISSUE ADAPTATIONS

LOADING

MECHANICAL STRESS

What is this

○ initiates the adaptation process.

○ CT can only adapt when it is progressively overloaded by increasing stress

LOADING

What is this

○ defined by the internal force observed divided by the cross-sectional area of the CT structure.

○ Less of this is placed on CT when the crosssectional area (denominator in the equation) increases per level of force encountered. Thus, CT increases tolerance for loading by increasing size and/or by altering structural properties.

MECHANICAL STRESS

Terms under STRESS RELATES TO THE FORCE APPLIED TO CT

TENSION STRESSES

COMPRESSION STRESSES

SHEAR STRESSES

DEFORMATION

What is this

result in pulling forces on the tissue.

● TENSION STRESSES ○

What is this

○ result in pushing the structure inward, or compressing its longitudinal length.

COMPRESSION STRESSES

What is this

○ result in skewing where force is encountered obliquely.

○ tend to be more injurious when encountered athletically.

SHEAR STRESSES

What is this

○ twisting effect, or torsion

○ leads to adaptation and is proportional to the level of stress encountered

DEFORMATION

Terns under STRESS-STRAIN RELATIONSHIP

STRESS

STRAIN (LINEAR, SHEAR)

ELASTICITY

PLASTICITY

What is this

- is the level of force encountered by a tissue

STRESS

What is this

- is the magnitude of deformation that takes place in proportion to the amount of stress applied.

STRAIN

What are the types of strain

LINEAR STRAIN

SHEAR STRAIN

This is a type of strain

is the tissue’s length change (in %) from compression or tension.

LINEAR STRAIN

This is a type of strain

is tissue bending measured by the angle of deformation.

SHEAR STRAIN

What is this

● It is the ratio of strain in the longitudinal direction to strain in the lateral direction.

● This is a useful measure to examine compression in articular cartilage and intervertebral disks (where too great of a strain can lead to a rupture)

POISSON’S RATIO

What is this

The property of CT to return to its original length after being stretched .

ELASTICITY ○

What is this

○ Chronic stretching can cause lasting elongation of tissue, which can be beneficial (e.g., tendons in flexibility training) or harmful (e.g., ligament damage).

PLASTICITY

Terms under SKELETAL SYSTEM: BONE ANATOMY

Canaliculi

Organic & Inorganic Region of Bone Matrix

What is this

○ Tiny channels in bone that move fluid, stimulating osteocytes to help bones adapt to stress.

Canaliculi

What is this

- mostly collagen, gives strength and flexibility.

Organic Region

Fill in the blanks

Organic Region

• mostly _____, gives strength and flexibility

Fill in the blanks

Organic Region

• mostly collagen, gives strength and flexibility

What is this

- minerals ( hydroxyapatites ) for hardness and compression resistance

○ Overall, bone consists of approximately 25%–30% of its content in water

Inorganic Region

Fill in the blanks

Inorganic Region

- minerals ( _____) for hardness and compression resistance

○ Overall, bone consists of approximately _____% of its content in water

Fill in the blanks

Inorganic Region

- minerals ( hydroxyapatites ) for hardness and compression resistance

○ Overall, bone consists of approximately 25%–30% of its content in water

TRUE OR FALSE: In order for remodeling to occur, functional cells must be activated to alter bone metabolism

TRUE

TRUE OR FALSE: In order for remodeling to occur, functional cells should not be activated to alter bone metabolism

FALSE

Terms under BONE REMODELING

OSTEOBLASTS

BONE ALKALINE PHOSPHATASE

OSTEOCLASTS

OSTEOBLASTS AND OSTEOCLASTS

What is this

○ are cells that secrete a collagen-rich ground substance (to help form the bone matrix) that aids in bone formation.

OSTEOBLASTS

What is this

○ involved in bone mineralization, which has been used as a blood marker of bone metabolism.

Bone Alkaline Phosphatase

What is this

○ cells involved in bone resorption, or breakdown.

○ they digest the mineralized bone matrix via acids and lysosomal enzymes thereby breaking down bone

Osteoclasts

Fill in the blanks:

● Osteoblasts and osteoclasts come from _____ cells and are controlled by hormones, growth factors, immune cells, nutrients, and exercise.

● A full bone remodeling cycle takes _____ months , so noticeable bone mass changes need at least _____ months

Fill in the blanks:

● Osteoblasts and osteoclasts come from stem cells and are controlled by hormones, growth factors, immune cells, nutrients, and exercise.

● A full bone remodeling cycle takes 3–4 months , so noticeable bone mass changes need at least 6–8 months

Terms under BONE GROWTH

INTRAMEMBRANOUOS OSSIFICATION

MEMBRANOUS OSSIFICATION

ENDOCHONDRAL OSSIFICATION

MECHANOTRANSDUCTION

BENDING

OSTEOCYTE

What is this

growth from CT membranes

INTRAMEMBRANOUS OSSIFICATION -

What is this

growth from cartilage

ENDOCHONDRAL OSSIFICATION -

Fill in the blanks:

Each bone has its own rate of metabolism; therefore, some bones fully reach their final length by age ____ and some may take as long as ____ years of age

Fill in the blanks:

Each bone has its own rate of metabolism; therefore, some bones fully reach their final length by age 18 and some may take as long as 25 years of age

What is this

- process where bone cells turn mechanical forces (loading) into internal signals

MECHANOTRANSDUCTION

What is this

- is proportional to the magnitude and rate of loading applied, bone deformation caused by load size and speed, from direct compression or tendon pull during muscle contraction.

BENDING

What is this

○ “sensor in the bone”

○ The bone’s “sensor, ” activated by fluid movement or electrical charges, opening ion channels for calcium and sodium, which trigger bone cell reactions.

OSTEOCYTE

Bone Adaptations to Exercise

_____

○ “Minimal Threshold Stimulus”

○ the minimum exercise volume and intensity needed to trigger new bone formation. Below this, bones won’t adapt. Adequate training can raise bone mineral density (BMD), though bone strength can also improve without BMD changes.

Certain exercises are better than others for increasing BMD.

● _____

●_____

●_____

Training guidelines for increasing bone mass:

● _____

●_____

●_____

●_____

● _____

● _____ tend to have higher BMD values than less-fit populations.

● _____tend to have greater BMD than age-matched, untrained population

● _____ have higher BMD than agematched sedentary individuals

● A short-term training program may not increase BMD

● BMD changes are typically seen after _____ months of training and only if an individual trains beyond their current threshold level of adaptation, or minimal essential strain

---

TRAINING TO INCREASE BONE SIZE AND STRENGTH

● Training programs designed to stimulate bone growth need to incorporate specificity of loading, speed and direction of loading, volume, proper exercise selection, progressive overload, and variation

Following general recommendations may be helpful

●_____

●_____

●_____

●_____

●_____

Bone Adaptations to Exercise

MINIMAL ESSENTIAL STRAIN

○ “Minimal Threshold Stimulus”

○ the minimum exercise volume and intensity needed to trigger new bone formation. Below this, bones won’t adapt. Adequate training can raise bone mineral density (BMD), though bone strength can also improve without BMD changes.

Certain exercises are better than others for increasing BMD.

● Dynamic, High-Intensity Loading

● Weight-Bearing Exercise

● Lifting and Contact Sports, and Sports/Activities requiring Explosive Running/Jumping (Plyometrics, Sprint, and Agility)

Training guidelines for increasing bone mass:

● Weight-bearing endurance exercises, activities that involve jumping, and resistance training (RT)

● Moderate to high exercise intensities

● Endurance exercise frequency of 3–5 days per week,

● RT frequency of 2–3 days per week

● Exercise for 30–60 minutes per day involving multiple training modalities (RT, endurance training)

● Stronger individuals tend to have higher BMD values than less-fit populations.

● Athletes tend to have greater BMD than age-matched, untrained population

● Resistance-trained athletes have higher BMD than agematched sedentary individuals

● A short-term training program may not increase BMD

● BMD changes are typically seen after 6 months of training and only if an individual trains beyond their current threshold level of adaptation, or minimal essential strain

---

TRAINING TO INCREASE BONE SIZE AND STRENGTH

● Training programs designed to stimulate bone growth need to incorporate specificity of loading, speed and direction of loading, volume, proper exercise selection, progressive overload, and variation

Following general recommendations may be helpful

● Multi-joint exercises (squats, power cleans, dead lifts, bench press).

● Loading should be high with moderate to low volume (10 reps and less).

● Fast velocities of contraction

● Rest intervals should be moderate to long in length (at least 2–3 min) to accommodate greater loading during each set

● Variation in the training stress

Terms under COMPONENTS OF DENSE CONNECTIVE TISSUE

Tendons and ligaments

Elastin

Collagen

Fascia

What is this

- dense fibrous connective tissues are made mostly of water (60–70%), collagen-producing cells, elastin, collagen, and ground substance.

Tendons and ligaments

What is this

is a protein that gives CT its elastic quality

Elastin

What is this

is the strongest, most abundant (20%–25% of total protein) protein in the human body

Collagen

Types of Collagen?

Types I and II

A type of Collagen that is found in skin, bones, tendons, and ligaments

Type 1

A type of collagen that is found in cartilage

Type 2

● _____ have a higher proportion of collagen whereas _____ possess a higher proportion of elastin

● _____ provide great strength and passive energy absorption whereas _____ tend to be more pliable .

● Tendons have a higher proportion of collagen whereas ligaments possess a higher proportion of elastin

● Tendons provide great strength and passive energy absorption whereas ligaments tend to be more pliable .

What is this

● has collagen fibers arranged in various directions for strength and joins into tendons to transmit muscle force to bone.

Fascia

Terms under TENDON, LIGAMENT, AND FASCIAL ADAPTATIONS TO TRAINING

MECHANICAL LOADING

Tendon Stiffness

What is this

○ The major stimulus for growth of tendons, ligaments, and fascia which leads to a cascade of events leading to hypertrophy.

● MECHANICAL LOADING

● The degree of adaptation is proportional to the intensity of exercise. The sites where CT can increase strength are:

○ at the junctions between the tendon/ligament and bone surface

○ within the body of the tendon/ligament

○ in the network of fascia within skeletal muscle.

What is this

○ (force per strain) increases with resistance training due to collagen reorganization, boosting strength even without size gain.

○ The intensity as heavy loads (80% of 1 RM) increase this but light loads (20% of 1 RM) may not

○ Interestingly, the response to training may be more prominent in men than women

Tendon Stiffness

Term under Cartilage Adaptations to Training

● Articular and Fibrous Cartilages

What is this

○ Provide smooth joint movement, absorb shock, and strengthen tendon/ligament attachments.

○ High-impact sports can increase the risk of degeneration of this structure and osteoarthritis, especially after injury.

● Articular and Fibrous Cartilages

● Buckwalter and Martin have suggested that athletes most susceptible to joint degeneration are those with:

○ Abnormal joint anatomy

○ Previous joint injury and/or surgery ○ Joint instability

○ Heavy body weight

○ Inadequate muscle strength

○ Altered muscle innervation