Study guide
14.3 Energy-System Application During Cardio Execution
NSCA Certified Personal Trainer NSCA-CPT
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1 Introduction & Exam Overview
1.1 Current Exam Facts, Format, and Domain Weights 1.2 Eligibility, Fees, Registration, and Retakes 1.3 Recertification, CEUs, and Professional Standing
2 Client Intake, Rapport, and Program Fit
2.1 Rapport, Compatibility, and Goal Discovery 2.2 Attitude, Readiness, and Ability to Participate 2.3 Relationship Expectations and Training Formats
3 Medical History, Clearance, and Referral
3.1 Medical History, Health Appraisal, and Lifestyle Questionnaires 3.2 Interpreting History and Obtaining Medical Release 3.3 Allied Healthcare Network and Referral Collaboration
4 Performance Evaluation
4.1 Structural Evaluation: Vitals, Anthropometrics, and Body Composition 4.2 Functional Evaluation: Mobility, Posture, Stability, and Gait 4.3 Fitness Evaluation: Strength, Endurance, Speed, Agility, and Power 4.4 Cardiorespiratory Testing, KPIs, and Reassessment
5 Basic Wellness Review
5.1 Nutrition and Energy Balance Within Scope 5.2 Sleep, Stress, and Wellbeing–Performance Links 5.3 RED-S, Disordered Eating, and Referral
6 Periodization and Session Architecture
6.1 Macro-, Meso-, and Microcycle Planning for Client Goals 6.2 Session Format, Length, Warm-Up, Modality, and Recovery 6.3 Exercise Order and Component Sequencing
7 Acute Variables, Tempo, and Progression
7.1 FITT Prescription and Work-to-Rest Ratios 7.2 Tempo, Time Under Tension, and Contraction Phases 7.3 Progression Plans and Reassessment-Based Modification
8 Special Populations: Age, Female-Specific Needs, and Athletes
8.1 Youth and Older Adults 8.2 Prenatal, Postpartum, and Postmenopausal Clients 8.3 Clients Training for Sport or Competition
9 Special Populations: Metabolic, Cardiovascular, and Orthopedic Conditions
9.1 Overweight, Obesity, Diabetes, and Metabolic Syndrome 9.2 Hypertension, Dyslipidemia, Post-Cardiac, PVD, and Stroke 9.3 Arthritis, Osteoporosis/Osteopenia, Musculoskeletal Trauma, and Rhabdomyolysis Awareness
10 Special Populations: Pulmonary, Neurologic, and Medical Complexity
10.1 Asthma and COPD 10.2 Neurologic, Cognitive, and Genetic Conditions 10.3 Cancer, Fibromyalgia, Immunologic/Hematologic Conditions, and Program Modification
11 Exercise Instruction and Coaching
11.1 Motivational and Coaching Techniques 11.2 Educating Clients on Exercise Purpose and Intent 11.3 Safety Guidelines, Breathing, and Teaching Biomechanics
12 Resistance Exercise Technique
12.1 Machine Resistance Technique 12.2 Free-Weight Squat and Hinge Patterns 12.3 Free-Weight Press and Pull Patterns 12.4 Kettlebells, Bands, and Water-Based Resistance
13 Mobility, Bodyweight, and Performance Technique
13.1 Flexibility and Mobility Technique 13.2 Calisthenic, Yoga, Torso, and Suspension Training 13.3 Plyometric Technique 13.4 Sprint, Agility, and Reaction Drills
14 Cardiovascular Exercise Technique
14.1 Cardiovascular Machines 14.2 Non-Machine Cardio: Walking, Running, Swimming, Aerobic Dance 14.3 Energy-System Application During Cardio Execution
15 Training Adaptations
15.1 Structural Adaptations: Muscle, Connective Tissue, Bone, and Adipose 15.2 Neuromuscular and Psychological Adaptations 15.3 Cardiorespiratory, Metabolic, and Endocrine Adaptations 15.4 Health Span, Longevity, and Using Outcomes to Modify Programs
16 Facility Safety and Client Monitoring
16.1 Exercise Environment and Equipment 16.2 Monitoring Responses and When to Consult Healthcare 16.3 Overtraining, Overuse, and Temperature-Induced Illness
17 Emergency Response, Legal Liability, and Ethics
17.1 First Aid and Facility Emergency Action Plans 17.2 Litigation, Negligence, and Liability Risk 17.3 Documentation, Informed Consent, Waivers, and Privacy 17.4 Professional Relationship, NSCA Code of Ethics, and Trainer Well-Being
14.3 Energy-System Application During Cardio Execution
Key Takeaways Explain This Topic AI
Phosphagen (~5–10 s), fast glycolysis (~15–30 s), mixed glycolytic/oxidative (~1–3 min), and oxidative (>~3 min) dominate different cardio tasks—all systems are always "on" to some degree.
Match work-to-rest to the goal: ~1:12–1:20 for 5–10 s phosphagen sprints; much denser rest for steady 20–60 min oxidative work.
Karvonen target HR = (HRmax − HRrest) × %intensity + HRrest; %HRmax is a different math and a common exam trap.
HIIT, moderate-intensity continuous training (MICT), and long slow distance (LSD) are tools—choose them from the goal, not from marketing.
Excess post-exercise oxygen consumption (EPOC) is a modest extra recovery cost, not a magic fat-loss promise.
Last updated: August 2026
Energy systems while the client is actually moving
DCO 3.B.6–7 is how they move. This section is which metabolic demand you just created so the next interval, rest, or machine setting is not random. NSCA teaching (the same energy-system table used in NSCA strength-and-conditioning education) treats the pathways as overlapping, with a primary system by duration and intensity:
- Primary emphasis Typical duration Example cardio task Common work:rest (NSCA table)
- Phosphagen (ATP–PCr) ~5–10 seconds Very short sprints, hill bursts, assault-bike all-outs 1:12 to 1:20
- Fast glycolysis ~15–30 seconds 200–300 m repeats, hard rowing pieces 1:3 to 1:5
- Fast glycolysis + oxidative ~1–3 minutes 800 m efforts, tough 2-minute bike intervals 1:3 to 1:4
Oxidative >~3 minutes , often 20–60+ min Steady jog, easy spin, long swim 1:1 to 1:3 if intervalled; continuous if MICT/LSD
A 10-second treadmill sprint therefore needs about 2–3.5 minutes of recovery if you actually want phosphagen quality on the next rep (10 s × 12 = 120 s; 10 s × 20 = 200 s). A 20–60 minute conversational ride is oxidative by design—do not sprinkle 10-second rests as if that were the same session.
Crossover concept
As intensity rises , carbohydrate supplies a larger share of energy and fat a smaller share (the crossover ). That does not mean low-intensity work is the only way to lose fat. Fat oxidation can be relatively high at easy paces, but total calorie burn and weekly volume still drive body-composition change. Do not tell clients that the treadmill's "fat burn" LED is a physiology law, or that they must stay below an unpublished magic heart rate forever.
All three systems contribute in mixed sessions. HIIT uses phosphagen and glycolytic bursts with oxidative recovery between reps. LSD sits on the oxidative end. Your coaching sentence on the floor is: match the clock and the rest to the system you meant to train.