NESTA-PFT cheat sheet

Acute responses to aerobic exercise: heart rate and stroke volume rise, so cardiac output increases; systolic blood pressure rises while diastolic stays near baseline; blood flow is redistributed to working muscle.

Fick equation: VO2 = cardiac output (L/min) x arteriovenous oxygen difference (mL O2 per 100 mL blood); cardiac output = heart rate x stroke volume.

Muscle fiber types: type I fibers are slow-twitch, oxidative, fatigue-resistant; type IIa are fast-twitch oxidative-glycolytic; type IIx are fast-twitch glycolytic with the lowest fatigue resistance.

ATP resynthesis systems and dominant fuel by duration: phosphagen (0-10 s), fast glycolysis (10 s-2 min), oxidative system (>2 min); intensity, not duration alone, determines the mix.

Force-velocity relationship: as concentric shortening velocity increases, force output decreases; eccentric contractions can produce greater force than maximal isometric actions.

Length-tension relationship: active tension is greatest at near-resting sarcomere length because actin-myosin crossbridge overlap is optimal; too short or too long reduces force.

Progressive overload, specificity, and reversibility are the core training principles: adaptation requires overload above current threshold, is specific to the imposed demand, and is lost with detraining.

Muscle spindles detect stretch and drive the stretch reflex; Golgi tendon organs sense tension and inhibit contraction, protecting against excessive load.

Energy cost and heart rate: heart rate rises roughly linearly with steady-state oxygen uptake across moderate intensities, which is why HR is used to estimate exercise intensity.

FITT-VP framework: Frequency, Intensity, Time, Type, Volume, and Progression; every program should specify each variable explicitly.

ACSM aerobic volume guideline for health: 150 min/week of moderate or 75 min/week of vigorous aerobic activity, or an equivalent combination, plus 2+ days/week of resistance training.

1RM estimation from a submaximal set: estimated 1RM = weight lifted / (1.0278 - 0.0278 x repetitions completed), valid for loads around 1-10 reps.

Load-to-repetition relationship: roughly 1-5 reps at 85-100% 1RM for maximal strength, 6-12 reps at 67-85% for hypertrophy, and 15+ reps at 65% or less for muscular endurance.

Rest interval selection: 2-5 min between heavy strength sets, 30-90 s between hypertrophy sets, and 30 s or less between endurance sets.

Periodization: linear models progress from high volume/low intensity to low volume/high intensity; undulating models vary volume and intensity within the week.

Progression rule: increase load or volume by roughly 2-10% when the client completes the prescribed sets and reps with good form and no excessive soreness.

Warm-up structure: 5-10 min of light aerobic activity plus dynamic mobility and movement rehearsal; static stretching held before power or strength work can transiently reduce force output.

Program design must match the client's goals, training status, injury history, and available equipment; specificity means the training mode should resemble the target outcome.

Exercise order: large-muscle, multi-joint movements before small-muscle isolation work, and higher-power or technically demanding lifts before fatiguing sets.

Rating of perceived exertion (RPE) 0-10 or 6-20 Borg scale is a valid intensity monitor when heart rate or load-based measures are unavailable or unreliable.

Talk test: a client who can speak in full sentences is generally at moderate intensity; inability to speak more than a few words indicates vigorous intensity.

Heart rate reserve (Karvonen) method: target HR = ((HRmax - HRrest) x intensity%) + HRrest; percent HRmax = target HR / HRmax x 100.

Estimated HRmax = 220 - age is a population average; individual variation is about plus or minus 10-12 beats per minute, so it should be treated as an estimate.

Form cues should be short, external, and specific to one correction at a time; excessive cueing during a set disrupts breathing and motor learning.

Spotting and safety: use a spotter for heavy barbell presses and overhead work, set safety pins in racks, and never spot a lift the client cannot control.

Session monitoring: record load, reps, sets, RPE, and any pain or form breakdown; these data drive the next progression decision.

Special populations: hypertensive clients should avoid holding breath and heavy overhead work; pregnant clients should avoid supine exercise after the first trimester and high fall-risk activities.

Session pricing: price = (target annual income + business expenses) / billable sessions per year; billable sessions are always fewer than total working hours.

Break-even point in sessions = fixed costs / (price per session - variable cost per session); variable costs include per-session supplies and payment processing fees.

Client retention is cheaper than acquisition: raising retention by a small margin usually improves profit more than an equivalent increase in new-client marketing.

Informed consent and health screening (e.g., PAR-Q+ style questionnaires) should be completed and documented before training begins; records support both safety and liability defense.

Scope of practice: a fitness professional may design and supervise exercise but may not diagnose, prescribe diets for medical conditions, or provide physical therapy.

Client records should be kept current and confidential, with objective progress data (measurements, loads, adherence) reviewed at scheduled reassessments.

Contract terms should state cancellation policy, payment schedule, session expiration, and refund rules in writing before the first paid session.

Referral network: physicians, physical therapists, and dietitians are appropriate referral sources when a client presents with signs outside the trainer's scope.