Chapter 1 Flashcards
Body Fat is stored as what in the body?
Triglycerides, stored both in fat (adipose) cells located between the skin and muscles all over the body, as well as within skeletal muscles.
Fit Female body fat range?
21%-24%
Fit male body fat range?
14%-17%
Normal ejection fraction? Exercise ejection fraction?
50%
100%
What is the significant limitation to exercise performance?
the capacity of muscles to extract oxygen from the bloodstream to produce energy. (Note that it is no the inability to breathe fast enough).
What is the energy used to drive the contraction?
ATP, adenosine triphosphate
3 ways the body replenishes ATP>
- Aerobic system
- Anaerobic glycolysis
- Creatine phosphate system.
Mitochondria definition
the site of aerobic energy (ATP) production. The greater the number of mitochondria in a cell, the greater the aerobic energy production capability of that cell.
How does the Anaerobic system work?
In the absence of sufficient oxygen, the muscle relies primarily on the anaerobic systems, which provide a rapidly available source of ATP. the anaerobic production of ATP occurs inside the cell, but outside the mitochondria.
Energy production at rest?
Contrast well-trained vs. non-trained person.
Since the heart is able to supply oxygen to the mitochondria of the muscle cells, both fatty acids and glucose are used to produce ATP. So, ATP is produced aerobically, using both fatty acids and glucose.The body produces about one calorie per minute at rest. About 50$ of this one calories per minute comes from fatty acids, even in an untrained person. In a well0trained endurance athlete, fatty acids provide as much as 70% of the resting caloric expenditure.
What happens when the body can no longer increase its delivery of oxgen into the mitochondria of exercising muscles to aerobically produce enough ATP?
the anaerobic system steps in to rapidly produce ATP. The Anaerobic threshold. This corresponds to the upper limit of sustainable aerobic exercise and it generally occurs in the range of 50% to 85% of maximum effort.
The primary source of anaerobic ATP production is?
What is the secondary source?
Glucose, which is carried in the blood and also is stored in muscles and the liver as glycogen (a large molecule made up of chains of glucose).
The secondary source of anaerobic ATP production is creatine phosphate, a molecule that can be quickly broken apart. There is an extreme limited supply of creatine phosphate. (only about 10 sec worth of max effort)
As long as a muscle cell is aerobic it uses what to produce ATP?
fatty acids and glucose, because the aerobic system uses fat (9 calories caloreis of energy per gram) the aerobic system produces much more ATP than the anaerobic systems.
Byproducts of Aerobic system?
Water and CO2, both are easy for the body to deal with, so aerobic energy production does not lead to muscle fatigue.
Byproducts of Anaerobic ATP?
lactic acid, heat, and hydrogen ions.
Why do we hyperventilate during Anaerobic ATP production?
When inadequate oxygen is available, the muscle signals the brain to increase the rate and depth of breathing. However, the limiting factor is not usually the ability to increase the rate and depth of breathing. It is primarily the ability to extract and use oxygen at the muscle. Hyperventilation is a futile process.
Maximal oxygen consumption definition
AKA VO2 max, the total capacity to consume oxygen at the cellular level. This represents an individual’s maximum aerobic capacity. VO2 max depends on 2 things:
1. the delivery of oxygen to the working muscles by the blood or the cardiac output
2. the ability to extract the oxygen from the blood at the capillaries and use it in the mitochondria. So VO2 max is
(cardiac output max) x (oxygen extraction max)
Client has a HR of 60 bpm, and stroke volume of 70 mL/beat, and oxygen extraction is 6 mLO2/100 mL of blood (so 6%), what is their resting VO2?
60 x 70 = 4200ml Liters per minute x 6% = 252 ml O2/min.
Note that is this patient weighs 70 kg, their VO2 would be 3.6 ml/kg/min
What is one MET?
One Metabolic equivalent is the resting VO2 of 3.5 mL/kg/min
Why does diastolic pressure decrease with exercise?
Because of the dilation of blood vesse;;s in the muscles decreases the amount of periphearal resistance in the vascular system.
Changes in VO2 max for a trained athlete?
- new capillaries are produces in the active skeletal muscles increasing the area for exchange of oxygen
- a significant increase in the mitochaondrial density, which means more of the muscle cell is occupied by mitochondria.
- Increased activity of mitochondrial (aerobic) enzymes.
4 things to consider for the correct type of aerobic exercise?
- the correct type
- the correct frequency
- a sufficient duration
- the proper intensity
Borg’s Rule?
The rate of perceived exertion (RPE)
What does a warmup do?
- increase in the temperature of the muscle and connection tissue, reducing the risk of soft tissue injury.
- allows the cardiovascular system to effectively adjust blood frlow from the abdominal area to the active muscles where the need fro oxygen is increased in response to the exercise while maintaining adequate venous return.
Slow-twitch (type 1) fibers definition
Contact more slowly than fast-twitch. Have a smaller cross-section than fast-twitch, have many mitochondria and a high aerobic capacity and therefore are the most resistant to fatigue.
Fast-twitch (type 2) fibers definition
Divided into Type 2a (more mitochondria) Type 2b (fast glycolytic) Neither has near the endurance or aerobic capability of slow-twitch
What kind of fibers would a power lifter have more of?
Fast-twitch, around 60-90%
Muscle contraction impulse
- Originates as nerve impulse from the brain to the muscle through a motor neuron.
- The neurotransmitter called acetylcholine chemically transmits the nerve impulse to muscle fibers
- The motor neuron and a myofibril (strands of protein running the length of each muscle fiber including the contractile proteins actin and myosin) meet at the neuromuscular junction
4.
Sliding filament theory
In order for a muscle contractino to occur there must be sufficient ATP near the actin and myosin proteins and there must be a nervous impulse from the CNS. When this occurs the tiny projections from the myosin attach to the actin, forming an actin-myosin cross bridge. The energy from ATP causes the myosin heads on each end of the myosin to swivel toward the center of the sarcomere, pulling on the attached actin filament so that the actin slides inward toward the center of the sarcomere. This causes each sarcomere along the entire length of the muscle fiber to shorten and the muscle contracts.
Muscle contraction summary
- A nerve impulse from the brain causes motor neuurons to release acetylcholine into the neuromuscular junction.
- The Aceylcholine is detected and the nerve impulse continues to spread across the sarcolemma and deep into the sarcoplasmic reticulum.
- The sarcoplasmic reticulum releases calcium into the sarcoplasm of the muscle fiber.
- The calcium binds with the proteins (troponin and tropomyosin) along the actin filament and exposes the binding sites for the myosin filament.
- With sufficient ATP, myosin binds with the actin to from cross-bridges.
- The myosin pulls the actin toward the center and the sarcomere shortens.
- Once a nervous impulse ceases, calcium is returned to the sarcoplasmic reticulum and the linkages between myosin and actin are broke.
Concentic contraction defintion
Positive contraction that shortens the muscle
Eccentric contraction definition
Negative contraction that lengthens the muscle.
Isometric contraction
contraction of individual fibers, but no change in the length of the whole muslce, Isometric means same length, it refers to exercises that develop high-intensity contractions in the muscle with no change in muscle length. so maximal effor against an immovable object. Like plank
3 types of connective tissue
Cartilage - serves as padding between the bones that meet at a joint in the skeleton
Ligaments - connect bones to bones at a joint
Tendons - connect skeletal muscle to bones transmitting the force of muscle contractino to the bones.
What accounts for the initial gains is someone who has never strength trained before?
The recruitment of previously inactive motor units is responsible for much of the initial increase in strength.
Nervous inhibition?
Both psychological and physiological. Physiological (functional) adaptation happens in the tendons, which connect the muscle to the bones, there is a sensor called a muscle tendon organ, or Golgi tendon organ. It is a protection against generating too much contractile force. When the muscle tendon organ is stimulated by too much contractile force, its associated muscle will relax to prevent injury to the muscle itself or to its associated connective tissues.
Isotonic
Same tone or tension - refers to exercises that use a given amount of external resistance that is challenged through the entire range of motion.
Isokinetic
Same speed - refers to a type of resistance exercise that causes the exercising muscles to generate a maximum amount of force throughout the entire range of movement, while keeping the speed of movement constant.
Muscle fatigue that happens in less than 30 sec?
This is because the active muscle cells run out of ATP at the site of the actin-myosin crossbridge, which is part of the mechanism of muscle fiber contraction. Without ATP present, the fibers can no longer contracct.
Muscle Fatigue that occurs from 30 sec to 40 - 60 minutes?
From lactic acid accumulation.
Muscle fatigue felt from 60-180 minutes?
From glycongen becoming depleted in the exercising muscle.
Flexability is primarily limited by four factors?
- the elastic limits of the ligaments and tendons crossing the joint
- The elasticity of the muscle tissue itself
- the bone and joint structure
- the skin.
Chondro
cartilage
Components of blood, how many liters do we have?
- different types of living blood cells (white blood cells, red blood cells, platelets)
- Plasma - nonliving liquid portion of blood, about 92% water and 8% dissolved soolutes
Woman have about 4 - 5 liters, men have 5 - 6 liters
Cervical plexus
Spinal nerves C1 - C4 whos nerves supply the head, neck, upper chest, and shoulders
Brachial plexus
spinal nerves C5 through T1, supplying from the shoulder down to the fingers of the hand
Lumbar Plexus
Spinal nerves L1 through L4 - innervating the abdomen, groin, genitalia, and antero-lateral aspect of the thigh
Sacral Plexus
Spinal nerves L4 - S4 - supplies the large muscles of the posterior thigh and the entire lower leg, ankle, and foot
Long Bone definition and parts
Parts
- Shaft called a diaphysis and two ends known as epiphyses that are usually wider than the shaft
- the diphysis is surronded by a connective tissue sheath called the periosteum that serves as an attachment site for muscles and tendons, and an inner layer that, when disrupted by fracture, signals the release of osteoblast (bone-forming cells) to repair the fracture
Bone components
Collagen, connective tissues
Wolff’s law
Bone is capable of adjusting its strength in proportion to the amount of stress placed on it. So when healthy ppl participate in resistance-training programs for extended periods, their bones will beome more dnse through increases in collagen fibers and mineral salts. Th opposite happens with no training
Cartilaginous joins
synchondroses - the bones are united by cartilage, no joint exists, similar to fibrous joints, little or no motion occurs. Ex. joints formed by hyaline cartilages that connect the ribs to the sternum and fibrocartilages taht separate the bodies of vertebrae in the spinal column.
Explain a synovial (diarthroses) joint?
the ends of the bones in hyynovial joints are covered with a thin layer of articular cartilage. 2. The joints are surrounded by an articular or joint capsule made of dense, fibrous connective tissue. 3. the inner surface of the joint capsule is lined with a thin synovial membrane.
The primary function of the synovial membrane is the secretion of synovial fluid to provide lubrication for the joint.
Part of a synovial joint that is an articular disk? what does it do?
Menisci (singular = meniscus). made up of fibrocartilage for weightbearing joints like the knee. The cartilages help to absorb shock, increase joint stability and aid in joint nutrition by directing the flow of synovial fluid and increas the joint contact area, thereby decreasing the pressure on the weightbearing structures.
differentiate synarthroses, amphiarthroses and diarthrodial joints
syn = together, amphi = both sides, dia = apart. so not movable, slightly movable, very movable.
Axis of rotation
Must be present in a joint to move in a given plane, it is an imaginary line perpendicular to (at a right angle to) the plane of movement about which a join rotates.
Joints with one axis of rotation
can only move in one plane and are known as uniplanar joints. aka hinge joints. The ankle (talocrural) and the elbow (ulnohumeral)
Joints with 2 axes of rotation
Biplanar joints - permit motion in two planes that are right angles to one another.. The knee (tibiofemoral) joint (this is a modified hinge joint) the joints of the hand and fingers (metacarpal/phalangeal), the condyloid joint and the joints of the feet and toes (metatarsal/phalangeal joints).
Joints with three axes of motion
Multiplanar joints - permmit movemetn in three planes. The hip joint and the shoulder (glenohumeral) both are ball-and-socket joints and the thumb (the first metacapal/phalangeal joint) which is a saddle joint.
Explain the metatarsaophalangeal joint
Synovial condyloid, it has two axes of motion (biplanar) Flexion and extension,
abduction and adduction and cirumduction
Explain the ankle joint?
Talocrural - synovial hinge joint with 1 axes of rotaion (uniplanar) plantarflexion and dorsiflexion
Explain the joint between distal tibia and fibula?
Fibrous, 0 axes of rotation, slight movement possible if any
Explain the joint between the knee (tibia and femur)
Synovial (modified hinge) 2 axes of rotation (biplanar) flexion and extension, internal and external rotation
Explain the hip joint
Synovial (ball and socket) with 3 axis of rotation causes flexion and extension, abduction and adduction, circumduction, internal and external rotation
Explain the metacarpophalangeal joint
Synovial (condyloid) 2 axis of rotation flexion and extension, abduction and adduction, circumduction
Explain the thumb joint?
Synovial saddle 3 axis of rotation flexion and extension, abduction and adduction, circumduction and opposition
Explain the wrist joint
Radiocarpal - synovial with 2 axis of rotation (biplanar) flexion and extension, abduction and adduction and cirumduction
Explain the proximal radiolunar joint
synovial pivot with 1 axis of rotation, pronation and supination
Explain the elbow joint
Ulna and humerus - synovial hinge with 1 axis of rotation, flexion and extension
Explain the shoulder joint
synovial (ball and socket) with 3 axis of rotaion flexion and extension, abduction and adduction, circumduction, interanl and external roation
Explain the ribs and sternum joint
Cartilaginous 0 axis of rotation with slight movement possible
What plane do flexion and extension happen in?
Sagittal plane
What plane do abduction and adduction movements occur in?
The frontal plane
Inversion of the foot
Occurs in the frontal plane, llifiting the medial border of the foot (only at the subtalar joint)
What occurs in the transverse plane?
Rotation, pronation, supination, horizontal flexion, horizontal extension
aponeurosis
a broad, flat type of tendon. The wide flat insertion of the rectus abdominis is an example
The anterior tibial compartment muscles
contract to extend the toes and dorsiflex the ankle. 1. anterior tibialis 2. extensor digitorum longus 3. hallucis longus
The lateral tibial compartment muscles
Know as the peroneals, cause eversion of the foot and plantarflexion of the ankle
The posterior muscles of the leg
contains superficial and deep posterior tibial compartments. The largest muscles of the calf (soleus and gastrocnemius) and the smaller plantaris are in the superficial part. The deep part contains the popliteius, posterior tibialis, flexor hallusic longus and the flexor digitorum longus.
These muscles work together to cause plantarflexion of the ankle, flexion of the toes, and inversion of the foot.
The posterior muscles of the leg
contains superficial and deep posterior tibial compartments. The largest muscles of the calf (soleus and gastrocnemius) and the smaller plantaris are in the superficial part. The deep part contains the popliteius, posterior tibialis, flexor hallusic longus and the flexor digitorum longus.
These muscles work together to cause plantarflexion of the ankle, flexion of the toes, and inversion of the foot.
Quadracepts femoris
4 major muslces grouped together located on the front of the knee in the anterior, or extensor, compartment. Their primary function is to extend the knee.
- Rectus femoris
- Vastus medialis
- vastus intermedius
- vastus lateralis
The muscles in the posterior, or flexor, compartment of the thigh?
Biceps femoris, semitendinosus, and semimembranousus. AKA the hamstring, cause flexion of the leg.
Pes Anserine group
Includes the semitendinosus and the sartorius and the gracilis. They all insert on the medial tibis, just below the knee.
Iliopsoas muscle
The psoas major, the psoas minor, and the iliacus grouped together. Flex the thigh, think three muscles to flex the thigh.
The recuts femoris also causes flexion of the thigh.
What muscles work together to adduct the femor?
The adductor magnus, adductor longus, and adductor brevis. They are all located on the medial aspect of the thigh.
Muslces responsible for movement of the vertebral column?
The iliocostalis, the longissimus, and the spinalis, aka the erector spinae.
Rectus abdominis
A narrow, flat muscle on the anterior aspect of the abdominal wall that flexes the vertebral column.
Muscles that act at the wrist to flex and pronate?
Flexors - flexor carpi radialis, palmaris longus, and flexor carpi ulnariis.
Pronator - pronator teres at the elbow, and the pronator quuadratus at the wrist.
Muscles that act at the wrist to extend and supinate?
Extensors - extensor carpi radialis longus, and the extensor carpi ulnaris
Rotator cuff muscles?
SITS
S - supraspinatus - abducts the arm
I - infraspinatus - exteranally rotate the arm
T - teres minor - externally rotates the arm
S - subscapularis - internally rotates the arm
Rotary movement
An object that is tied down at a fixed point and turns around that fixed point in rotary (angular) motion. The body usually moves like this
Translatory motion
aka linear motion - all parts move in the same direction and at the same speed.
Curvilinear motion
both rotary and translatory motion. Ex. Reaching for an object, the forearm and hand move straight towards that object in a translatory movement. The shoulder and elbow is doing a rotary movement.
When motions at various joints are simultaneously linear and rotary?
“general plane motion” Ex. riding a bicycle, some body segments also experience rotary motion around the joints.
Motive Force
causes an increase in speed or change in direction. ex. the contracting muscle
Resistive Force
resists the motion of another external force ex. gravity acting on the body segment and the dumbbell during contraction
explain the forces during a bicep curl?
Concentric - motive force is the bicept it is getting shorter, resistive force is gravity because it is resisting the move
eccentric - motive force is gravity because it causes the downward movement, the resistive force is the elbow flexor contractino because it resist the downward motion.
Isometric?
When muscle tension is created but no apparent change in length occurs
Lever
a rigid bar with a fixed point around which it rotates when an external force is applied. The fixed point is called its fulcrum
fulcrum
The fixed point of a lever. the center of a joint acts as a fulcrum for rotary motion of the body segments.
