11.10 Chapter Summary

• Muscle Tissue Types and Function: There are three types of muscle tissue: skeletal (voluntary movement), cardiac (involuntary rhythmic contractions of the heart), and smooth (involuntary movement in organs). All share properties like contractility, extensibility, and elasticity, which are essential for human function and movement.
• Joints and Movement: Joints are classified as synovial (freely movable), cartilaginous (slightly movable), and fibrous (immovable). Synovial joints, including hinge and ball-and-socket joints, play the most significant role in movement. Joint components like tendons, ligaments, menisci, and bursae provide support and reduce friction.
• Soft Tissue and Joint Injuries: Common injuries include sprains (ligament damage), strains (muscle or tendon damage), dislocations, and subluxations. These can result from overuse, trauma, or improper technique. Inflammation (e.g., tendinitis, bursitis) is the body’s healing response, but it can impair motion when excessive or chronic.
• Muscular Dysfunction and Disorders: Movement can be impaired by muscular issues such as muscle weakness, rigidity, and spasticity, often due to conditions like muscular dystrophy, Parkinson’s disease, or cerebral palsy. These dysfunctions reduce strength, coordination, and range of motion, sometimes affecting vital organs or posture.
• Conditions Affecting Movement: Neurological, musculoskeletal, metabolic, and psychological conditions can all impact physical function. Examples include osteoporosis, obesity, diabetes, depression, and fear of falling. These affect energy, posture, motivation, proprioception, and gait, demonstrating how holistic body health is essential to movement.

OpenAI. (June 17th, 2025). ChatGPT. [Large language model]. https://chat.openai.com/chat. Prompt: Summarize the following content into five key takeaways.

• Addison’s Disease: A disorder affecting hormone production, causing fatigue and reduced stress tolerance.
• Arthritis: Inflammation of joints, resulting in pain, stiffness, and reduced movement.
• Bursa (Bursae): A fluid-filled sac that reduces friction between bones and soft tissues, but when inflamed, is known as bursitis, which causes pain and can restrict movement.
• Contusion: Bruising caused by a direct blow, resulting in internal bleeding under the skin.
• Depression: A mental health condition that can reduce motivation, energy, and participation in physical activity.
• Diabetes: A metabolic condition that can impair nerve function and reduce proprioception.
• Dislocation/ Subluxation: Complete/ Partial separation of bones in a joint from normal position.
• Elasticity, Extensibility, and Contractility: The ability of a muscle to return to, stretch beyond, and shorten compared to its resting length.
• Fear of Falling (FOF): A psychological condition that affects walking and balance due to anxiety about falling.
• Hypothyroidism: A condition that slows metabolism and can cause muscle stiffness and fatigue.
• Inflammation: The body’s protective response to injury or infection, causing swelling, pain, and heat.
• Ligaments: The connective tissue which connects bone to bone, which works to stabilize joints and limit movement (e.g., your medial cruciate ligament or MCL in your knee, restricts side-to-side movement outside of typical hinge joint flexion and extension).
• Menisci: Crescent-shaped cartilage that absorbs shock and helps distribute joint pressure.
• Muscular Dystrophy (MD): A group of genetic disorders causing progressive muscle weakness and wasting.
• Osteoarthritis: A degenerative joint condition caused by wear and tear of cartilage.
• Osteoporosis: A condition where bones become weak and brittle due to low bone density.
• Parkinson’s Disease: A neurological condition causing tremors, rigidity, and slowed movement.
• Plantar Fasciitis: Inflammation of the plantar fascia, a thick band of tissue along the sole of the foot.
• Proprioceptive: The body’s ability to sense movement, action, and location.
• Rheumatoid Arthritis: An autoimmune condition causing chronic joint inflammation.
• Rigidity: Increased muscle tone that resists movement equally in both directions and speeds.
• Sliding Filament Theory: Explains muscle contraction via action and myosin filaments sliding past each other within the sarcomere (the smallest functional unit of muscle contraction).
• Spasticity: Increased muscle tone with resistance that increases with movement speed; often causes jerky movements.
• Sprain: Injury to a ligament due to overstretching or tearing.
• Stress Fracture: A small crack in bone caused by repetitive force or overuse.
• Strain: Injury to a muscle or tendon due to overstretching or overuse.
• Synovial Joint: A freely movable joint with a fluid-filled cavity, such as the knee or shoulder.
• Tendons: The connective tissues which connect bones to muscles and transmit force from muscle to produce movement (e.g., the patellar tendon connects the quadriceps muscle group to the tibia and plays a key role in knee extension).
• Tendinitis: Inflammation of a tendon, often from repetitive motion.
• Vertigo: A condition causing dizziness or a sensation of spinning, affecting balance.

OpenAI. (June 10th, 2025). ChatGPT. [Large language model]. https://chat.openai.com/chat. Prompt: List the key terms and their definitions in the content provided.