GR. 12 FITNESS Health Unit 1 Mr. Mackay

LEARNING GOALS Skeletal System: Structure & Function Adaptations to Training Joints: Basic Joints & Movement Muscular System: Structure & Function Adaptation to Training Energy Systems: Types and Function Adaptations to Training

Skeletal System Made up of all the bones, teeth and connective tissue of the body. –Ligaments, tendons, cartilage Adult has 206 bones, children 300. Skeleton provides: –Support: Holds up body –Protection: For organs, brain, spinal cord –Movement: Provides structure for muscles to move body.

SKELETAL REGIONS Axial Skeleton: Main torso: –Skull, ribs, sternum, Vertebrae Appendicular Skeleton: Extremeties –Limbs, pelvis, shoulders

ANATOMY OF BONE Outer Layer: Made of compact bone. Very dense and hard. Inner Layer: Spongy bone. Medullary Cavity: Bone marrow produces new blood cells. –Osteoblasts work to build new bone. Bones made of calcium (hard) and collagen (soft).

BONE HEALTH Diet: Food with calcium & protein. Exercise: Helps to densify bones and make them stronger. Protection: Use protective equipment when participating in risky activities.

EXERCISE ADAPTATION When loaded, bone is strained and breaks down where stressed. Osteoblasts, along with protein and calcium, work to strengthen the bone at the stress points. Calcification occurs and the bone is strengthened…densified. Cortical bone of the appendicular skeleton densifies more than spongy bone. 7

EXERCISE ADAPTATION Minimal Essential Strain (MES) is the threshold amount of stress applied to bone necessary to elicit growth of new bone. Force > MES is required to signal osteoblasts production. MES = ~1/10 of breaking force. Training effects have a positive relationship to bone density.

EXERCISE ADAPTATION Specificity of Loading: Exercises that target desired areas of strength gains and associated bone loading. –Upper Body: Bench Press, Shoulder press Compound Exercise: Promotes greater osteogenic stimuli. Compound movement consists of multi-joint structural loading and varying force vectors. –Cleans, deadlift, squats 9

EXERCISE ADAPTATION Progressive Overload: Greater than normal loads force greater MES, more adaptation, greater bone densification. –65% - 75% - 90% (12 reps, 8 reps, 3 reps) Variations in Exercise: Body adapts quickly to exercise. Program should provide variations to exercises. –Bench Press, dumbbell, incline, blast straps, etc. 10

SYNOVIAL JOINTS Freely Moveable Motion dictated by the shape of the bones in the joint and by supporting soft tissue. e.g., muscle attachments and joint capsules (ligaments) Movements are described traditionally by the actual direction the bones move. 11

SYNOVIAL JOINT 12

SYNOVIAL JOINTS 13

SYNOVIAL JOINT MOVEMENT Flexion: Closing of a joint angle. Extension: Opening of a joint angle. Abduction: Sideways movement away from body. Adduction: Sideways movement towards body. Internal / External Rotation: Rotation of a bone along its axis. Circumduction: Combination of 4-movements to create circular motion at ball-and-socket joint. 14

15