1.Glycogen

CATEGORY:

•Synthesised Energy Form

DEFINITION:

•Energy storage form of Carbs (Glucose) in Liver (for brain [primary form of energy used...Ketones a reserve form] and other organs) & Muscles

FUNCTION:

•Primary form of Energy supply for bodily function

-Other sources include...

—Amino Acids (Protein component)

—Glycerol (Fats component)

—Ketones (Fats byproduct)

—Lactate (Metabolic byproduct of activity)

•Secondary long term energy...Adipose Tissue (Body Fat stored as Triglycerides) is primary

•Glycogen energy form readily available in absence of Oxygen for Anaerobic Metabolism, making it a more efficient form of energy supply than Triglycerides

ACTION:

•Liver and Muscle Glycogen Stores are reduced overnight (metabolism dependent) leading to Low Blood Sugar levels in the morning

-The Brain can utilise up to 75% of Liver Glycogen Stores

-Hormones that attempt to raise Blood Sugar are stimulated...

—Glucagon

—Cortisol

—NPY

•Low levels lead to fatigue and loss of athletic performance

-A factor in post-exercise recovery

•Through Synthesis (combining) and Genesis (creation) and Metabolism (Catabolic or Anabolic) mechanisms the body is supplied with sources of ATP from Glycogen

•Released from Liver to aid digestion

-Foods that are complex to digest increase the activation of Glycogen in digestion

•Gluconeogenesis is a Metabolic Pathway that replenishes Glycogen Stores

-Ongoing process whereby Amino Acids contribute to Blood Sugar even if Glycogen Stores are not depleted

FACTS:

•Also found in Fungi

•Glucose ingested (rather than created in Liver) circulates in body for longer and produces greater Insulin and Leptin Resistance

•Consists of 1 part Glycogen with 3 to 4 parts water (thus the importance of maintaining hydration)

•Stored capacities...

-1500-2000calories

-Liver = 100g

-Muscles = 400g (1% per Muscle Mass)

—Athletes can store 1000g of Glycogen (3500cals)

•Stores last for...

-Muscles...

—Aerobic Activity = 90mins

—Anaerobic Activity = 20mins

—In excess of 24hrs in the absence of exercise

-Liver = 24hrs

MANIPULATION:

•Excess Calories stored as Fat within 4-8hrs of eating...exercise within timeframe of consumption

-Hi GI fluids (Soft drinks & Fruit juice) = 45mins

-Hi GI solids (Chocolates & Sweets) = 60mins

-Fruit = 75mins

-Carbohydrates = 90mins

•CarboLoading...Glycogen store depletion followed by high volume Carb consumption increases capacity of intramuscular Glycogen stores

-Carbohydrates are more suited to replenish Glycogen Stores as do not activate Insulin

•Muscle Glycogen Stores are distinct to each muscle...one muscle cannot deplete/utilise Glycogen stores from another

-Rational for TBT and Aerobic activities e.g swimming, running etc utilising all muscle groups (especially large ones)

-Muscle Glycogen Store depletion correlates positively with intensity of training...rational for HIIT

•Low-Carb diets can deplete Muscle Glycogen

DIETING:

•High GI foods readily convert to Glucose, so avoid unless exercising

-Safest consumption of High GI foods is peri adequate exercise

•First 1000cals of meal go in to Glycogen Storage

RELATED TO:

•Glycolysis 

•Gluconeogenesis

•Lipogenesis & Triglyceride Synthesis

•Lypolysis

•Ketosis

•SNS

•Glugcaon

•NPY

•Water

NOTES:

•Consuming Caffeine with Carbs replenishes Glycogen rapidly...avoid unless exercising - how does this relate to Cortisol and SNS/PSNS?!?!?

•Glycogen Stores depleted when SNS is activated...how does this relate to sleep then?!?!

•Glycogen storage capacity relates to BMR (1500-2000cals)?!?!?