Energy Systems · Performance Science
You're not undertrained.
You're training the wrong energy system.
@drdragutin
01 / 08
The Full Spectrum
3 Systems.
One Body.
Phosphagen
ATP-PC System
0 — 10 sec
Glycolytic
Lactate System
10 sec — 2 min
Oxidative
Fat + Carbs
2 min +
@drdragutin
02 / 08
01
Energy System · 01
PHOSPHAGEN
SYSTEM
0 – 10 seconds
ATP-PC
Explosive
Maximum effort. Zero oxygen required. The body draws directly from stored ATP and phosphocreatine. This system is your only option when pure power is demanded instantly.
Duration
0–10 seconds — fully depleted by then
Fuel
ATP + Phosphocreatine — stored in muscle
Oxygen
Not required — fully anaerobic
Recovery
3–5 minutes for full replenishment
Best for
Sprints, jumps, maximal lifts, contact sports
@drdragutin03 / 08
02
Energy System · 02
GLYCOLYTIC
SYSTEM
10 sec – 2 min
Lactate
High Intensity
The burn you feel. Glycolysis breaks down glucose rapidly without oxygen. Lactate accumulates. This system drives repeated high-intensity efforts — and it's the one most athletes both overuse and undertrain.
Duration
10 seconds – 2 minutes at high output
Fuel
Muscle glycogen + blood glucose
Byproduct
Lactate + H⁺ — the "burn" signal
Oxygen
Anaerobic — but lactate IS usable fuel
Best for
400m, MMA rounds, HIIT, repeated sprints
@drdragutin04 / 08
03
Energy System · 03
OXIDATIVE
SYSTEM
2 min +
Fat + Carbs
Aerobic
Your engine, not your limit. The oxidative system uses oxygen to produce ATP from fat and carbohydrates. Slower to activate, but nearly unlimited in capacity.
Duration
2 min → hours — essentially unlimited
Fuel
Fat dominant at low intensity; carbs at higher
Oxygen
Required — fully aerobic
Key adapt.
Mitochondrial density + fat oxidation rate
Best for
Endurance, recovery between efforts, base fitness
@drdragutin05 / 08
The Plateau Problem
Most athletes
live in the
middle.
And that's exactly
why they
plateau.
@drdragutin
06 / 08
Neurotyping × Energy Systems
YOUR NEURO-
TYPE DECIDES.
Your neurotype determines which energy system you naturally favor — and which one you're unconsciously avoiding.
Training the wrong system for your neurotype doesn't just slow progress. It creates chronic fatigue, frustration, and burnout.
Type 1A
Type 1B
Type 2A
Type 2B
Type 3
@drdragutin
07 / 08
Next Step
TRAIN THE
RIGHT
SYSTEM.
Discover your neurotype. Identify your dominant energy system. Build a program that actually works for how you're wired.
drdragutin.com/resources.html
Energy Systems × Neurotyping · Link in Bio
@drdragutin
08 / 08