Water & Electrolytes
Define Electrolyte
An electrolyte is an ion that carries an electrical charge in body fluids. They are essential for nerve transmission, muscle contractions and maintaining fluid balance
Identify what macro this is
C6H12O6
Carbohydrate
Define Dietary Recommendation
These are set standards developed by governments and health authorities based on scientific evidence
Define metabolism
Metabolism is the total sum of all chemical reactions occurring in the body, including energy production and storage.
State what is Carbohydrate Loading Diet
Carbohydrate loading is a dietary strategy aimed at increasing muscle glycogen stores before endurance events to ensure sufficient energy for prolongued periods of time
State how much fluid in our bodies is extracellular and intracellular
2/3 (66%) of fluid is intracellular fluid: inside cells
1/3 (33%) of fluid is extracellular fluid: outside cells
Proteins
Fats
Carbohydrates
Water
Vitamins
Minerals
Outline Dietary Guideline
Target food, food groups or meals and are set by country to guide its people towards a health balanced diet.
Influenced by sociocultural factors like religion, social norms, food security, food prices etc
Outline ATP
a molecule created by catabolic reactions
ATP stores and supplies energy for all biological functions
ATP connects anabolic and catabolic reactions
Ingested food 🡪 stored as fats or glycogen 🡪 catabolism 🡪 ATP 🡪energy
Outline ATP in Muscle Contraction
All muscle fibers have the capacity to make ATP using different macronutrients like carbohydrate and fats as energy sources. When the muscle fiber is stimulated to contract, ATP provides the chemical energy needed for contraction
Muscles store insufficient amounts of ATP – enough for 2 seconds of muscular contraction but afterwards its needed from a source. These sources are from these systems
Phosphagen System (ATP-PC System)
Glycolytic System (Anerobic Glycolysis)
Oxidative System (Aerobic Metabolism)
Outline the 4 types of loss of water and electrolytes
1. Sweating (evaporation via skin) Sweating is a process where water and electrolytes are lost to cool the body
2. Respiratory water loss (breath vapor) When breathing, moisture is lost through water vapor in exhaled air
3. Urine Excretion (kidney filtration) Kidneys regulate water and sodium loss based on hydration status. Increased urine production occurs when hydration is sufficient.
4. Fecal Water Loss (osmotic excretion via the intestines) Large intestine absorbs most water, but some is lost in feces.
Distinguish the difference between a macronutrient and a micronutrient, as well as their respective units
MACRONUTRIENTS
Provide calories or energy and are required in large amounts
Carbohydrates
Proteins
Lipids (fat)
Water
MICRONUTRIENTS
Required in small amounts to orchestrate a wide variety of physiological functions
Vitamins
Minerals
fiber
Compare and Contrast between low glycemic and high glycemic index
Low Glycemic Index (GI)
Carbohydrate foods with higher levels of fiber
Digested slower and provide a steady release of glucose
Provide sustained energy levels during prolonged exercise
Examples: whole grains, fruit
High Glycemic Index (GI)
Carbohydrate foods with minimal fiber and more sugar
Digested rapidly and cause quick spikes of glucose
Provide immediate energy for short bursts of intense exercise
Examples: white bread, potatoes
Compare & Contrast Between Anaerobic and Aerobic Characteristics
Anaerobic
muscle cells must rely on other reactions that don’t require O2 to fuel muscle contraction
(oxygen isn’t present)
Non-oxygen conditions (high intensity exercise)
Only burn carbohydrates
Strengthens tendons, ligaments, and joint functions
Elevate good cholesterol (HDL)
Aerobic
muscle cells can contract repeatedly without fatigue
With oxygen
Uses oxygen to burn fat and carbs to produce energy
Reduce resting HR, increase the number of red blood cells
Ex: Walking, climbing, dancing,tennis, basketball
Discuss the Nutritional Consequences – Gastrointestinal Discomfort
Gastrointestinal issues are the most common cause of underperformance inendurance athletes
Symptoms include: nausea, vomiting, diarrhea
Main causes:
Physiological – during exercise, blood flow to the intestines is decreased
Mechanical – high impact of repetitive forces on inner organs or posture issues
Nutrition – high fiber, fat and protein are known to make gastrointestinal issues worse; dehydration can also worsen symptoms
Describe Osmoregulation
The critical homeostatic process of maintaining constant water and electrolyte balance in body fluids. Primarily managed by the kidneys, this mechanism uses a feedback loop involving the hypothalamus and hormones to regulate water reabsorption, ensuring proper cell function and preventing dehydration or overhydration.
Outline the main functions and storage of a carbohydrate
Main Functions:Provide fuel for the body
Acts as energy storage (in muscle and liver as glycogen)
Breaks down fatty acids and prevents ketosis (elevated level of ketone in the blood)
Storage: in muscle and liver as glycogen ( used for short-term, intense, anaerobic activities)
Excess can be converted and stored as fat
Quicker accessibility as an energy source than protein or fat
Discuss Hydration and Electrolyte Replacement Dietary Plan
Fluid loss (due to sweating) can result in dehydration. This leads to reduced performance, muscle cramping, heat exhaustion and fatigue
Sweating leads to the loss of water and electrolytes. Both need to be replaced to avoid hyponatremia
Replacing electrolytes is essential for maintaining nerve function, muscle contractions and hydration
Sports drinks containing sodium, potassium, and other electrolytes for exercise are recommended for durations longer than 1hr to ensure hydration and prevent cramping
Describe the ATP-PC System
Anaerobic: ATP-CP System
Creatine Phosphate (CP): A high energy molecule, is broken down to provide a phosphate molecule fro the resynthesis of ATP that has been utilized during the initial stages of exercise
Most readily available system
Short-term and intense activities that require lots of power create high demand for ATP
Re-synthesis: CP stored in skeletal muscle donates a phosphate to ADP to produce muscle contractions
Does not require oxygen to resynthesize ATP
Fatigue occurs rapidly
Discuss the Kidney's use in osmoregulation
The kidneys are essential organs for maintaining electrolyte balance, regulating water content in the body, and filtering waste from the blood
Kidneys regulate fluid and electrolyte balance through processes of filtration, reabsorption, and excretion
Filtration: blood is filtered through the kidneys’ glomeruli and substances like water, sodium, potassium and other solutes are separated from waste products
Reabsorption: the majority of water and electrolytes (including sodium and potassium) are reabsorbed back into the bloodstream in the proximal convoluted tubule, loop of Henle and distal convoluted tubule
Secretion and Excretion: waste products, excess water, and electrolytes are secreted into urine, which exits the body via the ureters and bladder
Describe the hypothalamus's job in Osmoregulation
Hypothalamus acts as the body’s osmoregulation center – monitoring blood osmolarity (solute concentration)
Detects changes in water and electrolyte balance and triggers appropriate responses to maintain homeostasis
Osmoreceptors detect changes in blood osmolarity. If blood osmolarity increases (due to dehydration or excess sodium intake), the hypothalamus signals for water retention to dilute the excess solutes. If blood osmolarity decreases (due to overhydration or low sodium levels), the hypothalamus signals for water excretion to restore balance. Triggers Thirst Mechanism: when osmolarity is too high, the hypothalamus stimulates the sensation of thirst, encouraging increased water intake
Signals the pituitary gland to release antidiuretic hormone (ADH) to regulate kidney function and control water retention
Discuss the Chemical Composition of a Lipid
Composed of carbon, hydrogen, and oxygen
Base unit is a fatty acid
Triacylglycerol (TAG) are storage lipids stored mostly in adipose cells and tissues which are highly concentrated sources of metabolic energy
Composed of three fatty acids attached to a glycerol skeleton
Discuss the Nutritional Consequences – Effects of
LEA and RED-S
Decreased bone density
Low energy availability disrupts the body’s ability to regulate bone resorption and formation – makes bones more fragile
Insufficient calorie intake leads to lower levels of estrogen (in females) and testosterone (males) – both key hormones in bone health
Hormonal Imbalances
Disrupt hormones in metabolism and reproduction
Women – leads to menstrual dysfunction like the absence of menstruation
Men – low testosterone
Also impacts hormones that regulate metabolism, mood and overall health
Reduced performance
Body does not have the necessary energy to fuel exercise and recovery – leads to fatigue, decreased endurance, slower reaction times and impaired recovery
May struggle to complete workouts and have increased risk of injury
Describe the Lactic Acid System
Lactic Acid System (Anaerobic Glycolysis)
The breakdown of glucose (carbohydrates) to pyruvate without the use of oxygen
Glucose 🡪 ATP + pyruvate = 2 molecules of ATP
Quick energy
Pyruvate is converted into lactic acid, which limits the amount of ATP produced (two ATP molecules)
2nd fastest way to resynthesize ATP
Used for all-out exercise lasting from 30 seconds to 2 minutes
Lactic acid accumulates in the muscle and causes discomfort and reduces the ability of muscle to contract (slows down)
Describe the Aerobic System with an example
Aerobic Energy Systems
This system is very efficient at re-synthesizing ATP from all main food groups
Functions when oxygen is present
Most complex of the three energy systems
Slowest way to resynthesize ATP
Includes the Krebs Cycle (citric acid cycle) and the electron transport chain
Uses blood glucose, glycogen, and fats as fuels to resynthesize ATP in the mitochondria of muscle cells
Glucose Oxidation
Production of energy from glucose in the presence of oxygen. Glucose is first broken down into pyruvate is converted into Acetyl CoA and is processed by the Krebs Cycle. The Krebs Cycle liberates electrons that are then passed through the electron transport chain producing energy (ATP)