General Overview of Exercise Metabolism

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General Overview of Exercise Metabolism
Just about anything you eat is metabolized to
carbon dioxide water with the concomitant
synthesis of ATP to provide the chemical energy
necessary to build and repair cellular components
or to sustain muscle contraction.
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An Exercise-Centric View of Metabolism
The ATP generated is used up by muscle
contraction and a variety of metabolic reactions
regenerate the ATP predominantly through 4 basic
processes 1-Myokinase reaction 2-Creatine
Phosphokinase reaction 3-Glycolysis (in
cytosol) 4-Oxidative Phosphorylation (in
mitochondria)
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We should not however, view ATP generation for
muscle contraction as the only metabolism
happening metabolism of carbohydrates, lipids,
proteins provides the chemical energy ATP
necessary for all normal cellular functions
maintaining membrane potentials, synthesizing
hormones, DNA, neurotransmitters, membranes
proteins in order to replace the ones damaged by
radicals and oxidants or to grow new muscle
cells to increase strength or to grow new fat
cells when we eat too much proteins (and a whole
bunch more).
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Getting back to the ATP thing, these are some of
the major metabolic pathways for
metabolism Glycolysis produces pyruvate for
acetyl CoA production in mitochondria, produces
NADH (electrons) for ETC in mitochondria,
anaerobic production of ATP MK CPK anaerobic
production of ATP TCA accepts acetyl-CoA for
citrate synthesis, production of NADH (electrons)
TCA-intermediates can be used for synthesis of
lipids, DNA, RNA, many amino acids,
etc. ß-oxidation produces acetyl CoA for
TCA Transamination produces pyruvate, or acetyl
CoA, or TCA ETC electrons from TCA cycle
glycolysis are joined to oxygen to make water
the production of ATP Pentose Phosphate Pathway
production of ribose and NADPH for nucleotide and
other synthesis processes
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In many cases, vitamins and minerals play a
functional role by being part of the structure of
the proteins and/or enzymes (superoxide
dismutase, xanthine oxidase, catalase, alcohol
dehydrogenase, hemoglobin, glutathione
peroxidase), or being co-factors (NAD, FAD, FMN,
etc.) so various enzymes can do their job, or
being part of functional molecules (ATP, GTP,
etc.)
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And it is the physical properties of the amino
acids within a protein that determines structure
and function. Primary structure of a protein is
the order in which the amino acids are joined
together . . .
Secondary structure refers to how the amino acids
interact to produce different shapes . . .
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Tertiary structure refers to how the different
secondary structures interact to produce the
three-dimensional structure of the protein
Leucine Zipper
Zinc-finger
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The different kinds of structural shapes in a
protein are held together by a variety of
different forces Charge interactions -
positive and negative amino acids attract -
like charges repel Disulfide bonds two
sulfur-containing amino acids can covalently
bond RC-SH HS-C-R ? 2H
R-C-SS-C-R Hydrophobic interactions
hydrophobic amino acids will attract to each
other (eg. Leucine) Multivalent metal
coordination metal ions bonding with multiple
amino acids in a single protein (heme, zinc
fingers)
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Quaternary structure refers to the structural
interactions between more than one tertiary
structure
Two alpha-heme molecules join to two beta-heme
molecules to produce the protein hemoglobin.
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Some quaternary structure interactions alter the
function of a protein.
HSP90
ER
Estrogen receptors can exist in the monomer
steroid-binding form as well as in the dimer DNA
binding form notice the role of the
leucine-zipper motif and the zinc-finger motif
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An example of vitamin and mineral use within the
glycolysis pathway
In addition Mg must be present for the ATP
(or ADP) to bind To synthesize ATP molecule in
the first place you need Folic Acid, Thiamine,
Cobalamin, PO4, Zn, Cr, Mg Niacin is a
component of NAD
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Some Nutritional Requirements For This Process
Include Protein synthesis - requires DNA, RNA,
mRNA, GTP . . . - synthesis enzymes require
Cr?, Mg, Zn to function and amino acids for
structure Synthesis of DNA, RNA, ATP, GTP . .
. - folic acid, B12, glucose, aa, PO4 (structure)
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In order for the metabolic pathways to work, the
enzymes (proteins) must be synthesized in the
first place . . . Enzymes perform chemical
reactions of metabolism - requires (protein)
synthesis of enzymes (duh!) - many enzymes
contain minerals as part of their structure -
many enzymes require co-factors which contain
vitamins as part of their structure. Some
Nutritional Requirements For This Process
Include Protein synthesis - requires DNA, RNA,
mRNA, GTP . . . - synthesis enzymes require
Cr?, Mg, Zn to function Synthesis of DNA,
RNA, ATP, GTP . . . - folic acid, B12, glucose,
aa, PO4 (structure) - enzymes for synthesis
require Zn,Cr?, Mg, to function
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Obviously, in order to ensure that we can
maintain appropriate metabolic functions we need
to have the proper nutrients.
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Unfortunately, the average American diet Really
Sucks . . .
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With obvious results,,,
Poor
Poor levels of antioxidant vitamins
Inadequate function of Antioxidant Redox
Control Enzymes
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Number of Food Servings for Daily Caloric
Intakes Food Group Standard Approximate
2000 2200 2500 2800 Serving Size
Calories / kcal kcal kcal kcal
Serving Fruits 0.5 cup 71 5
5 5 5 Vegetables 0.5 cup
38 6 6 6 6 Cold-Water
Fish 4 ounces 120 2/wk 2/wk 2/wk
2/wk (Lean Meats on 3 ounces 120
- - - - remaining days) Nuts Seeds 0.25
cup 240 1 1 1
1 Beans Legumes 0.5 cup 110 2
3 3 3 Dairy 1.0 cup/2 oz.
86 3 3 3 3 Breads
Cereals 1 slice/1 oz 78 5 6
7 7 Red Wine 4 oz 85
1 1 1 1 Added Fats 1 Tbsp
(EVOO) 110 2 2 3
3 Discretionary Calories - - 200
400
In order to get the nutrients you need Ya gotta
do this