Ex Phys Exam 3

SA node

Pacemaker of the heart, starts every heartbeat

AV node

Stalls the signal for 1/10th of a second so that the upper chambers can push blood into the ventricles

AV bundle

A piece of muscle that runs to the two branches

Purkinje fibers

Stimulate right and left ventricular contraction

Cardiac conduction system

Specialized cardiac muscle cells that initiate and transmit action potentials (this has to happen for every beat to contract)

What makes up the cardiac conduction system

SA node, AV node, AV bundle (left and right), Purkinje fibers

What are the extrinsic controls of the heart

Sequence’s of PNS and CNS

Sequence of PNS

1. An electrical signal travels through the vagus nerve. 2. The vagus nerve release acetylcholine. 3. ACh binds to receptors on SA and AV node cells. 4. Hyperpolarization of conduction cells (no cells can contract during this time) 5. Slower spontaneous depolarization. 6. Decreased HR and decrease force of contraction

Sequence of SNS

1. Signal travels through the sympathetic cardiac nerves. 2. SCN releases norepinehrine. 3. NE binds to receptors on the SA and AV node cells. 4. Depolarization of conduction cells. 5. Faster spontaneous depolarization. 6. Increase HR and force of contraction

ECG

Records of the electrical activty of the heart (monitoring cardiac changes or diagnosis or cardiac problems)

3 phases of ECG

P wave, ORS complex, T wave

P wave

Atrial depolarization initiated by the SA node; triggers atrial contraction

QRS complex

Ventricular depolarization; triggers ventricular contraction

What two events happen in the QRS complex

Atria relax and ventricles contract

T wave

Ventricular repolarization; allows ventricles to depolarize again (resting phase)

What are the 3 adaptations to resistance training

Neural adaptations, muscle hypertrophy, fiber type alterations

Neural adaptations (adaptation of resistance training)

Strength gains cannot occur without neural adaptations (increased neural drive, improved motor unit synchronization, and increased motor unit recruitment)

Muscle hypertrophy (adaptation of resistance training)

An increase in size of the muscle due to structural changes in the individual muscle fibers

2 types of muscle hypertrophy

Transient and chronic

Transient muscle hypertrophy

Short term size increase after acute bouts of exercise due to fluid accumulation (edema)

Chronic muscle hypertrophy

Long term due to enhanced protein synthesis of muscle myofibrils, structural changes

Fiber type alterations (adaptation of resistance training)

Characteristics of type 2x show myosin change to type 2a

Protein timing

If your next meal is within 5 hours, consume at least 20 grams, if it is over 5 hours, consume 40 grams

Protein quantity for young individuals

Minimum = 0.8 g, Recommended = 1.2 - 2.2 g/kg/day, 4 meals at 32 g = 128 g/day

Protein quantity for older individuals

Minimum = 1.2 g, Recommend = 1.6 - 2.2 g/kg/day, 4 meals at 44 = 176 g/day

Best lifts (complex vs single joint)

The best exercises are compound lifts (squat, deadlift, bench press, pull ups, and rows) because they recruit multiple muscle groups and allow maximal force production, while single joint exercises are used as accessory work isolate and strengthen specific muscles

Adaptations to aerobic training

Increase VO2max, increase submaximal endurance capacity, lower HR at the same submaximal exercise intensity

Physiologically how do we increase ones aerobic fitness

Through cardiovascular and muscular adaptations that improve our body’s ability to deliver, extract, and use oxygen for energy production during exercise

%EF equasions

(SV/EDV) x 100 (unit %)

MAP equasion

(SBP - DBP)/3 + DBP (unit mmHg)

RPP equasion

SBP x HR

TPR

MAP/Q

Different types of LV hypertrophy

Concentric and esentric

Consentric hypertrophy

Resistance training (parallel)

Esentric hypertrophy

Aerobic training

Fiber type changes with different training

During resistance training or high intensity treadmill, type 2x shows myosin heavy chain of type 2a (both 1 and 2x take on characteristics of 2a)

Protein degradation and synthesis during resistance training

Synthesis decreases and degradation increases

Protein degradation and synthesis after resistance training

Synthesis increases and degradation decreases

Changes in Q

Increases considerably, HR and SV interact to optimize cardiac output

Changes in HR

Decreases overtime

Changes in SV

Increases with training, plasma volume increases which increases EDV, HR decreases so there is an increase in filling time so increases in EDV

Resistance training reps/sets for increases muscle mass is based off of

Power, strength, muscular endurance, hypertrophy

Reps and sets for increasing power single effort event

Load: 80-90% of 1 RM, Goal reps: 1-2

Reps and sets for increasing power multiple effort event

Load: 75-85% of 1RM, Goal reps: 3-5

Reps and sets for increasing strength

Load: greater than or equal to 85% of 1RM, Goal reps: less than or equal to 6

Reps and sets for increasing muscular endurance

Load: less than or equal to 67% of 1RM, Goal: greater than or equal to 12

Rest times for increasing muscle mass

Rest period between reps is anywhere from 30 sec - 5 min. 2-5 for strength and power and 3- seconds for hypertrophy and endurance

Reps and sets for increasing hypertrophy

Load: 67-85% of 1RM, Goal reps: 6-12