KNES 348 Chapter #1 (Cellular Reactions)

Kinesiology What is this?

The scientific study of human movement

Kinesis: To move

Logy: science or study of

What does the term Exercise Physiology mean?

The study of how the body physiologically responds, adjust, and adapt to exercise or the lack of exercise.

What is Metabolism?

Sum of all chemical reactions that occur in the body-two general categories of chemical reactions

Anabolic reactions are?

Synthesis of molecules

Catabolic reactions are?

The breakdown of molecules

What are Bioenergetics?

The process of converting foodstuffs (fats proteins, carbohydrates) into usable energy for cell work

What are Endergonic reactions?

Require energy to be added

What are Exergonic reactions?

Releases energy

What are coupled reactions?

Liberation of energy in an exergonic reaction drives an endergonic reaction

Classification of enzymes

Almost every enzyme names end with an (ase)

What does Kinases do?

Adds a phosphate group

What does Dehydrogenases (ases) do?

Removes hydrogen atoms

What are Oxidases?

Catalyze oxidation-reactions involving oxygen

What is Bioenergetics?

The process of converting foodstuffs (fats, proteins, carbohydrates) into usable energy for cell work

What is the formation of ATP?

• Phosphocreatine (PC) breakdown

• Degradation of glucose and glycogen (glycolysis)

What are Anaerobic pathways?

• Does not involve O2

• PC breakdown and glycolysis

What are Aerobic pathways

• Requires O2

• Oxidative phosphorylation, substrates utilized could be carbohydrate, fats, and protein

What is the Cell membrane? (Sarcolemma in skeletal muscle) Cell structure

Semipermeable membrane that separates the cell from the extracellular environment

Cell structure (Nucleus)

contains genes that regulate protein synthesis

cell structure (Cytoplasm) (sarcoplasm in muscle)

• Fluid portion of cell

• Contains organelles

• Mitochondria

Skeletal muscle fiber structure

Overview of Bioenergetics

What is Adenosine Triphosphate? (ATP)

• Energy from food that is not directly used to perform work

• Chemical energy stored in ATP comes from the food we ingest

• Immediately usable form of chemcial energy —→ emergency currency

  (Food Chemical Energy —> Converted inside body —> ATP Chemical Energy)

ATP - A Useful form of chemical energy in our bodies

The bond between each phosphate is termed a “high-energy” bond

ATP is formed through the process of metabolism (metabolism)

Sums of all chemical reactions

ATP is formed through the process of metabolism (catabolism)

breakdown of molecules

ATP is formed through the process of metabolism (anabolism)

synthesis or building of molecules

ATP-PC System: What is it?

High-intensity —> exercise utilizes ATP much faster than it can be produced aerobically

Phosphocreatine (PC) is similar to what?

• Similar to ATP: high-energy phosphate bonds

• stored in small amounts in the cytoplasm of muscle

ATP Molecule

Recreating ATP with PCr

Summary of Phosphagen System

• Provides energy for maximal activities lasting up to
  10 to 15 seconds (main system)

• It is somewhat important for activities lasting 30 to
  90 seconds

• It does not contribute heavily to activities lasting
  more than 90 seconds

Issues with the consumption of
nutritional supplements (Creatine)

• The US Federal Trade Commission regulates advertising
  and labeling

• The Food and Drug Administration does not analyze the
  content of the supplements

• The label may include the “other ingredients” statement

• The product may have other ingredients not disclosed

• No standard dose or serving size

information Creatine

• Creatine naturally occurs in the body and can
  be synthesized in the body (liver and kidneys)

• Healthy people gain and break down 2g/day

• Fish and red meat are the main sources in our diet

• Muscles store: creatine (70%) and PCr (30%)

Creatine loading effects for
performance summary

• Effective for short-duration events (seconds)

• Detrimental for endurance events (gains in body mass)

Creatine monohydrate

• 30 % of people are non-responders

  (Means you take the supplement, but do not see
  gains in PCr stores or creatine in the muscle)

• Gains in PCr stores can be about 40%

How does it work?
Proposed mechanisms of action

• Increased PCr availability, which means greater ability to make ATP from this system (longer or more)

• Increased rate of PCr resynthesis, which means
  increased ability to recover and use the PCr system
  intermittently. This is important for high intensity

• It does not stimulate protein synthesis; what leads to protein synthesis or muscle building is the training itself, which can be improved by supplementing with creatine
  intermittent activities