Study guide
2.1 Energy Systems, Workout Formats & Stimulus Selection
Certified CrossFit Trainer CCFT / CF-L3
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1 Chapter 1: Screening and Ongoing Assessment
1.1 Health & Medical Screening (PAR-Q+, Risk Stratification & Pre-Participation) 1.2 Referral Criteria & Medical Clearance Protocol 1.3 Rhabdomyolysis Risk Screening & Psychological Tolerance for Training 1.4 Movement Analysis & Baseline Physical Assessment 1.5 Evaluating Work Capacity Across Broad Time and Modal Domains 1.6 Goals, Progression Readiness, Overtraining Monitoring & Performance Tracking
2 Chapter 2: Programming - Designing Workouts and Cycles
2.1 Energy Systems, Workout Formats & Stimulus Selection 2.2 Volume, Intensity & Density Manipulation 2.3 Sequencing Workouts for General Physical Preparedness 2.4 Periodization Models (Linear, Conjugate, Block & Peaking) 2.5 Evaluating Programming: Benchmarks, Adjustment & CrossFit's Definition of Fitness
3 Chapter 3: Programming - Scaling for Every Athlete
3.1 Scaling & Modification Strategies for Varied Populations 3.2 Scaling by Age Group: Youth, Adolescent & Masters Athletes 3.3 Scaling for Special Populations: Pregnancy, Postpartum & Adaptive Athletes 3.4 Scaling & Programming for Athletes with Sport-Specific Goals 3.5 Programming for Injured Athletes: Maintaining Fitness & Restoring Function
4 Chapter 4: Educating - Teaching CrossFit Concepts
4.1 Teaching the Definition of CrossFit & the Character of Functional Movement 4.2 Teaching CrossFit's Definitions of Fitness and Health: The Four Models 4.3 Teaching the Goals of CrossFit Programming and How Variance Achieves Them 4.4 Teaching the Technique-Intensity Relationship, Threshold Training & Relative Intensity 4.5 Teaching the Principles of Scaling
5 Chapter 5: Educating - Teaching and Demonstrating Movement
5.1 Teaching Progressions & Points of Performance for Primary Lifts 5.2 Gymnastics Progressions & Body Control Mechanics 5.3 Group & Individual Instruction Methods 5.4 Designing Progressions for Complex Movements 5.5 Teaching and Using Correct Spotting Techniques 5.6 Demonstrating Movements, Faults and Progressions
6 Chapter 6: Training - Seeing Movement
6.1 Identifying Points of Performance Across the Foundational Movements 6.2 Recognising Sound Mechanics: What 'Good' Actually Looks Like 6.3 Fault Identification, Root-Cause Analysis & Contraindications 6.4 Identifying Faults in the Olympic Lifts and Gymnastics Movements 6.5 Root-Cause Analysis: Mobility, Stability, Motor Control or Load 6.6 Refining Sound Mechanics and Identifying Common Themes Across a Class
7 Chapter 7: Training - Correcting Movement
7.1 Cueing Strategies (Verbal, Visual, Tactile) & Feedback Loops 7.2 Selecting Corrective Cues: Short, Specific, Actionable 7.3 Reinforcing Sound Mechanics & Balancing Relentlessness With Acknowledgement 7.4 Applying Basic Principles of Anatomy and Biomechanics 7.5 Coaching the Midline: Bracing, Breathing and Spinal Position Under Load 7.6 Fault Triage: Addressing the Most Egregious Fault First 7.7 Refining Mechanics to Optimise Performance Under Fatigue 7.8 Intra-Session Adjustments & Real-Time Coaching Decisions
8 Chapter 8: Leadership and Management
8.1 Providing Athletes With Goal Setting 8.2 Building a Culture of Excellence and Establishing Rapport 8.3 Coach Development, Mentorship & Staff Supervision 8.4 Mechanics-Consistency-Intensity as a Management Strategy 8.5 Managing Athlete Risk, Recognising Overexertion & Teaching Personal Responsibility 8.6 Floor Flow, Class Structure & Time Management 8.7 Engaging Virtual and Remote Athletes 8.8 Safety Zones, Equipment Handling & Facility Setup 8.9 Balancing Individual Attention, Group Cohesion & Class Logistics 8.10 Athlete Onboarding & Retention Systems
9 Chapter 9: Lifestyle Education
9.1 Identifying Nutrition Goals and Assessing an Athlete's Nutrition 9.2 Providing Nutrition Guidance & Outlining Dietary Strategies 9.3 Zone Diet Block Calculations & Macronutrient Manipulation 9.4 Caloric Estimation & Sub-Population Nutritional Needs 9.5 Reviewing Basic Health Markers 9.6 Teaching Food Labels and Building Sample Meal Plans 9.7 Lifestyle Goals, Assessment & Scope-of-Practice Limits 9.8 Sleep, Stress Management & Recovery Modalities 9.9 Behavioral Change, Goal Setting & Habit Formation
10 Chapter 10: Professional Responsibilities and Ethics
10.1 Self-Assessment of Training Sessions & Pursuing Continuing Education 10.2 Legal Liability, Risk Management & Informed Consent 10.3 Facility Operations, Maintenance & Equipment Standards 10.4 Recognising and Responding to Extreme Environmental Conditions 10.5 Insurance, Employment Status & Truth in Advertising 10.6 Emergency Response, First Aid & Rhabdomyolysis Prevention 10.7 Scope of Practice & Interprofessional Collaboration 10.8 Standards of Professional Practice & Ethical Guidelines 10.9 Documentation, Incident Reporting & Record Keeping 10.10 Confidentiality, Client Records & Mandated Reporting
2.1 Energy Systems, Workout Formats & Stimulus Selection
Key Takeaways Explain This Topic AI
The phosphagen (ATP-PCr) system dominates maximal effort work lasting 0-10 seconds, requiring a 1:12 to 1:20 work-to-rest ratio for complete recovery.
The glycolytic system is the primary energy pathway for moderate-to-high intensity efforts lasting 10-120 seconds, producing lactic acid as a byproduct.
The oxidative (aerobic) system sustains submaximal efforts longer than 2 minutes and facilitates recovery between high-intensity anaerobic bouts.
An AMRAP (As Many Rounds/Reps As Possible) workout prioritizes continuous movement and tests pacing and metabolic endurance under fatigue.
EMOM (Every Minute on the Minute) formats train the ability to recover rapidly and execute precise skill/strength work in a pre-fatigued state.
Last updated: August 2026
Energy Systems in Mixed Modal Training
At the core of CrossFit programming is a deep understanding of bioenergetics—how the body produces, utilizes, and replenishes energy during high-intensity functional movements. A Level 3 Certified CrossFit Trainer must not only understand the independent function of each energy system but also how they interplay during mixed-modal workouts. Programming without acknowledging energy system constraints often leads to "junk volume" or an improper stimulus that fails to drive adaptation.
The Three Primary Energy Systems
Human movement is powered by adenosine triphosphate (ATP). Because the body stores very little ATP, it must be continuously resynthesized through three distinct energy pathways.
Phosphagen System (ATP-PCr): This system provides immediate energy for maximal-intensity, short-duration activities. It relies on stored ATP and creatine phosphate (PCr) within the muscle. The phosphagen system dominates activities lasting 0 to 10 seconds, such as a 1-rep max deadlift, a 50-meter sprint, or a heavy clean and jerk. It operates anaerobically (without oxygen) and produces energy rapidly, but its stores are quickly depleted. Recovery of this system requires 3 to 5 minutes of rest, corresponding to a work-to-rest ratio of 1:12 to 1:20.
Glycolytic System: When high-intensity effort continues beyond 10 seconds, the body shifts to the glycolytic system, which breaks down muscle glycogen and blood glucose to produce ATP. This system is the primary driver for efforts lasting between 10 and 120 seconds, such as a 400-meter sprint or an unbroken set of 30 thrusters. A byproduct of this anaerobic process is lactic acid, which dissociates into lactate and hydrogen ions, leading to a drop in muscle pH and the familiar "burning" sensation that causes fatigue. Proper recovery for glycolytic efforts typically demands a work-to-rest ratio of 1:3 to 1:5.
Oxidative (Aerobic) System: For continuous efforts lasting longer than 2 to 3 minutes, the oxidative system becomes the primary source of ATP. This system requires oxygen to metabolize carbohydrates and fats. While it produces ATP at a slower rate than the anaerobic systems, its capacity is virtually limitless, making it the engine for endurance events like a 5K run or a long 20-minute AMRAP. Crucially, a highly developed aerobic system also facilitates the clearance of lactate and speeds up the replenishment of ATP-PCr stores between high-intensity anaerobic intervals. Work-to-rest ratios for aerobic training are typically 1:1 or 1:0.5.
Bioenergetics of Mixed Modal Workouts
CrossFit’s constantly varied, high-intensity functional movements blur the lines between these energy systems. A workout like "Fran" (21-15-9 Thrusters and Pull-ups) is a classic example of a glycolytic test. Elite athletes complete it in under 3 minutes, relying heavily on the glycolytic pathway and generating massive amounts of lactate. In contrast, "Murph" (1-mile run, 100 pull-ups, 200 push-ups, 300 squats, 1-mile run) is primarily an aerobic test due to its duration, though it involves local muscular endurance that heavily taxes the glycolytic system. Designing mixed-modal workouts requires an understanding of how fatigue in one system affects performance in another.
Common CrossFit Workout Formats
The format of a workout dictates its pace, strategy, and ultimate physiological stimulus.
AMRAP (As Many Rounds / Reps As Possible): This is a time-priority format where the duration is fixed, and the athlete's work output is the variable. AMRAPs are excellent for testing pacing, mental fortitude, and aerobic/glycolytic capacity. Because the time domain is fixed, athletes learn how to manage their fatigue threshold.
EMOM (Every Minute on the Minute): EMOMs are structured interval workouts where a specific task is completed at the start of every minute, with the remaining time in that minute used for rest. This format is ideal for skill acquisition under fatigue, pacing practice, and energy system specific training (e.g., maintaining phosphagen output with heavy lifts or managing glycolytic clearance).
For Time (Task Priority): In a "For Time" format, the work is fixed, and the time to completion is the variable. This encourages athletes to push their intensity to the maximum, often testing their glycolytic threshold as they attempt to minimize transition and rest times.
Chipper: A Chipper typically involves a single round of several different movements performed in succession, usually with high volume. Chippers test muscular stamina and mental resilience, often requiring athletes to break sets strategically to avoid early muscular failure.
Tabata: Based on the research of Dr. Izumi Tabata, this format involves 8 rounds of 20 seconds of all-out work followed by 10 seconds of rest (4 minutes total). True Tabata intervals are designed to maximize both aerobic and anaerobic capacities simultaneously, though the 2:1 work-to-rest ratio makes complete recovery impossible, leading to a massive oxygen debt.
Targeted Physiological Stimulus
The effectiveness of a program hinges on clearly defining the intended stimulus for each workout. Is the goal to build absolute strength (phosphagen), improve lactate tolerance (glycolytic), or build a massive aerobic base? The stimulus dictates the loading, the volume, and the format. For instance, if the intended stimulus is a heavy, phosphagen-dominant effort, forcing an athlete into a 15-minute AMRAP of heavy deadlifts is counterproductive and dangerous; a 5x3 format with 3 minutes of rest between sets is appropriate. Mastery of programming involves matching the format, movements, and rep schemes to the precise physiological adaptation you are trying to elicit.