BIOENERGETICS AND METABOLISM

The flow of energy in a biological system, the conversion of macronutrients into biologically usable forms of energy

BIOENERGETICS

The breakdown of large molecules into smaller molecules is associated with the release of energy

Catabolism

The synthesis of larger molecules from smaller molecules can be accomplished using the energy released from catabolic reactions

Anabolism

Is catabolism exergonic or endergonic

Exergonic

Is Anabolism Exergonic or Endergonic

Endergonic

Exergonic

Energy relasing reactions that are generally catabolic

Endergonic

Require energy and include anabolic processes and the contraction of muscle

The total of all catabolic (exergonic) and anabolic (endergonic ) reactions in a biological system

Metabolism

Allows the transfer of energy from exergonic to endergonic reactions

Adenosine Triphosphate

What do bioenergteics and metabolism provide for muscle contraction during exercise

the needed energy

How do our bodies break down stored fuels

Through the metabolic pathway

What do metabolic pathways generate

ATP

During exercise, the rate of ATP production increases dramatically via what 3 energy systems

They power muscle contractions and enable us to perform exercise

Phosphagen (immediate)

Glycolytic (short term)

Oxidative (long term)

In excercise, what determines which energy system predominates

The intensity and duration

What are the 3 types of work that ATP does

Mechanical work

Chemical work

Transport work

How is all the enregy used by our bodies generated

from the breakdown of food and drink

the macronutrients are metabolized to create what?

ATP

What is the point of our many metabolic systems

Our bodies must constantly produce ATP

The body uses all 3 energy systems simultaneously, but why does it also depend on intesnity and duration?

Your body will choose what pathway it will use the largest percentage of its energy

Training intended to increase the storage(anabolic) and delivery (catabolic) of energy for specific sports/physical activities

Metabolic conditioning

Provides ATP for the first 10-20 seconds of high-intensity activity

OXYGEN NOT REQUIRED

phosphagen system

catalyzes the synthesis of ATP from PCr+ ADP

Creatine kinase

Where is ATP-PCr stored

in muscle

There is a high rate of energy production from the phosphagen system for immediate use but what is the downside?

It depletes rapidly

Why when we sprint at full speed for only seconds or lifting maximum loads 1-2 times before needing rest or a decrease in exercise intensity using another metabolic pathway

We have completley depleted the phosphagen system

Out of the the macronutrients ____ can be metabolized for energy without direct involvement of oxygen

Carbohydrates

How does anaerobic glycolytic pathway generate ATP

through the breakdown of glucose molecules from carbohydrates

Results in net production of 2 ATP

Glucose→Pyruvate→Lactate

Dominant energy pathway for moderate to vigorous physical activity lasting from 15 seconds- 3 minutes

ANAEROBIC GLYCOLYTIC SYSTEM

Does Lactic Acid Cause Metabolic activity?

No, ATP outside the mitochondria is primarily responsible for the proton accumulation during exercised induced metabolic acidosis

metabolic pathway in which lactate produced by anaerobic glycolysis in peripheral tissues (primarily skeletal muscle) is transported via the bloodstream to the liver, where it is converted back into glucose through gluconeogenesis.

Cori Cycle

For rest and submaximal exercise that lasts longer than 3 minutes, which pathway is preferred?

OXIDATIVE PATHWAY

What is the oxidative pathway?

utilizes oxygen in production of energy (aeroboic)

Occurs within mitochondria

uses fat as its primary energy source, produces enough ATP to sustain longer duration activities but only at submaximal exercise output

What is the predominant fuel source used during low to moderate intensity activity, like biking or jogging long distances

FAT

What do the oxidative metabolism of fat, carbohydrate, and protein share in common in terms of pathways?

They are all reduced to Acetyl-CoA and enter the Krebs cycle in mitochondria

Immediate: ATP-CP

0-10 seconds

Short Term: Lactic/Glyccolytic/Anearobic

10-60 seconds

Long Term: Oxidative/Aerobic

60-120 seconds

Metabolic adaptations to Anearobic Training

ATP-PCr system changes

Glycolytic enzyme changes

Buffering capacity changes

Increase in toleration of lactate

Metabolic Adaptations to Endurance Training

myoglobin content

carbohydrate and fat utilization increased

oxidative enzymes

Are anaerobic glycolytic enzymes significantly affected by prolonged endurance training?

NO

An increase in oxidative enzymes and mitochondrial density leads to glycogen sparing, which ultimately results in?

Decrease in lactate

Improve exercise tolerance during submaximal exercise

Increase in capillary density provides an enhanced opportunity to transport___ ___ ___ from adipose storage sites to excercising muscle

free fatty acids

Triglycerides stored in fat cells are released by LIPASE

breaks down triglycerides into glycerol and fatty acids

releases part of free fatty acids into blood, where they circulate and enter muscle fibers. Undergo beta oxdiation in mitochondria

Lipolysis (Fat Oxidation)

Break down fatty acid into acetyl CoA, FADH, NADH ,H+

some free fatty acids come from intramuscular sources, acetyl COA enter Krebs cycle

H+ atoms carried by NADH and FADH2 to electron transport chain

Beta Oxidation

1 triglyceride containing 16-carbon chain free fatty acids can be metabolized by beta oxidation to yield over _____ ATP molecules when using oxygen

300

Can fat be used without oxygen

No, It can’t be used without oxygen

Is proetin a significant source of energy for activities?

NO

The contribution of amino acids to the production of ATP is minimal during short term exercise but may contribute 3% ro 18% of the energy requirements during prolonged activity?

True/False

TRUE