homer2000
Iron
- Joined
- Feb 20, 2026
- Posts
- 8
- Reputation
- 5
Energy Substrates in Food
Your body's main sources of energy are prioritized like this: Glucose → Glycogen → Fat → Protein → Ketones (in that order)
These are called Energy substrates. Your body really likes glucose/glycogen because they're fastest and easiest fuel to use.
When you eat carbs/sugar, your body turns them into glucose (energy) in your small intestine.
Blood sugar = how much glucose is in your blood (aka how many carbs/sugar you just ate)
The Glycemic Index (GI)
The glycemic index (GI) tells you how fast carbs turn into glucose:
High GI - simple carbs = fast energy (rice, fruit, sugar)
Low GI - complex carbs = slow energy (oats, beans, potatoes)
Carb timing:
Before the gym
After the gym
If you eat more carbs than your body needs, it will store them as fat. Get that in your head.
You can easily look up your nutrition questions on chatgpt to explain it easier for you. Stop relying on others to find answers for you and get better at asking questions.
BASIC Q's:
Your body's main sources of energy are prioritized like this: Glucose → Glycogen → Fat → Protein → Ketones (in that order)
These are called Energy substrates. Your body really likes glucose/glycogen because they're fastest and easiest fuel to use.
When you eat carbs/sugar, your body turns them into glucose (energy) in your small intestine.
Blood sugar = how much glucose is in your blood (aka how many carbs/sugar you just ate)
The Glycemic Index (GI)
The glycemic index (GI) tells you how fast carbs turn into glucose:
High GI - simple carbs = fast energy (rice, fruit, sugar)
Low GI - complex carbs = slow energy (oats, beans, potatoes)
Carb timing:
Before the gym
- Eat higher GI carbs
- Purpose: quick energy for the workout
- Examples: banana, white rice, toast, honey
After the gym
- Eat mostly lower GI carbs + enough total carbs
- Purpose: recovery + steady energy
- Examples: oats, potatoes, beans, whole grains
If you eat more carbs than your body needs, it will store them as fat. Get that in your head.
You can easily look up your nutrition questions on chatgpt to explain it easier for you. Stop relying on others to find answers for you and get better at asking questions.
BASIC Q's:
- What are macronutrients?
- How does my body use protein, carbs, and fats?
- How many calories and macros should I eat for my goal?
- When should I eat and how should I time carbs around workouts?
- What foods should I eat to hit my protein, carbs, and fats?
- How do blood sugar, insulin, and the glycemic index affect energy and fat gain?
