Exercise Science and Training Principles
Domain 2: Exercise Science and Training Principles
This domain tests the mechanisms behind adaptation: bioenergetics, muscle physiology, neuromuscular adaptation, and the principles that govern training response. Questions often ask why a program works, not just what to do.
Core rules
- SAID principle: specific adaptation to imposed demands. Training must resemble the target task in muscle action, velocity, joint angle, and energy system.
- Overload, progression, recovery: adaptation occurs when stress exceeds current capacity and is followed by adequate recovery. More is not better; the dose-response has a ceiling.
- Strength gains early (0-8 weeks) are largely neural: motor unit recruitment, rate coding, intermuscular coordination. Hypertrophy accumulates later with mechanical tension and volume.
- Bioenergetics: phosphagen (0-10 s), glycolytic (10 s-2 min), oxidative (>2 min). Sprint and lift programming should match the dominant system and recovery.
- Fiber types: type I fatigue-resistant, type IIx/IIa fast and powerful. Training can shift IIx toward IIa; it cannot turn type I into type II.
- Fatigue is not one thing: peripheral (metabolite accumulation, excitation-contraction failure) and central (reduced drive). Recovery prescriptions differ.
Worked example
A client wants hypertrophy but can only train 3 days/week with dumbbells. Program 3 full-body sessions, 3-4 sets per muscle group, 8-15 reps, last set 1-2 reps from failure, 60-90 s rest. Reasoning: mechanical tension and volume drive hypertrophy; near-failure low-load sets recruit high-threshold units; full-body frequency spreads volume. Adding daily cardio to burn fat without calorie control would not improve hypertrophy and may blunt recovery.
Traps
- Lactic acid causes DOMS-DOMS is microdamage and inflammation; lactate clears within an hour.
- Muscle turns to fat with detraining-fat and muscle are separate tissues.
- Spot reduction-fat loss is systemic.
- High reps tone, low reps build-both can build muscle; effort and volume matter.
- Cardio kills gains-concurrent training can interfere, but sequencing, volume, and nutrition matter.