NCAA CPL Human Performance cheat sheet

Skeletal muscle hierarchy: myofilaments (actin, myosin) → sarcomere → myofibril → muscle fiber → fascicle → whole muscle; the sarcomere is the functional contractile unit, bounded by two Z-discs.

Sliding filament theory: myosin heads bind actin, the power stroke requires ATP hydrolysis and Ca2+ binding to troponin-C, which shifts tropomyosin off actin's myosin-binding sites.

Fiber typing: Type I = slow oxidative, high capillary density and mitochondrial content, fatigue-resistant; Type IIa = fast oxidative-glycolytic; Type IIx = fast glycolytic, highest peak power, fastest fatigue.

Motor unit = one alpha motor neuron plus all the muscle fibers it innervates; the innervation ratio (fibers per neuron) sets fine control (extraocular muscles ~10) versus gross force (gastrocnemius ~2000).

Muscle action classification: agonist/prime mover produces the movement, antagonist opposes it, synergist assists or stabilizes, fixator holds the proximal segment; eccentric actions generate the highest force at a given velocity.

Length-tension relationship: active tension peaks near optimal sarcomere overlap (~2.0-2.2 micrometers) and falls when the muscle is over-shortened or over-stretched.

Force-velocity relationship: concentric force falls as shortening velocity rises; eccentric contractions can exceed isometric force by roughly 20-60 percent but carry higher delayed-onset soreness risk.

Levers: first class (neck extension, triceps at the elbow), second class (calf raise, wheelbarrow), third class (biceps curl, most human limbs); third-class levers favor speed and range over mechanical advantage.

ATP-PCr (phosphagen) system: immediate, ~1:1 ATP yield from creatine phosphate via creatine kinase, dominant for the first 5-10 seconds of maximal effort, no oxygen required.

Anaerobic glycolysis: glucose or glycogen to pyruvate/lactate, net 2 ATP per glucose (3 per glycogen-derived glucose), dominant from ~10 seconds to ~2 minutes; lactate production is not the sole cause of acidosis (H+ from ATP hydrolysis also contributes).

Oxidative phosphorylation: carbohydrate yields ~30-32 ATP per glucose, fat yields far more per gram but at lower rate; dominant beyond ~2-3 minutes and the sole sustainable source at steady state.

The lactate threshold marks the intensity where blood lactate rises above baseline; the second (respiratory compensation) threshold approximates maximal lactate steady state and is a strong endurance performance predictor.

VO2max = cardiac output (Q) x arteriovenous oxygen difference; Q = heart rate x stroke volume; endurance training raises stroke volume and plasma volume more than it raises maximal heart rate.

Oxygen deficit at exercise onset and excess post-exercise oxygen consumption (EPOC) after exercise reflect the lag between ATP demand and oxidative supply; EPOC magnitude scales with intensity.

Crossover concept: as intensity rises from ~60 percent VO2max, carbohydrate contribution increases and fat oxidation declines, largely due to fiber recruitment and catecholamine-driven lipolysis limits.

Heart rate reserve (Karvonen): target HR = (HRmax - HRrest) x intensity percent + HRrest; estimated HRmax = 220 - age is a population average with roughly +/-10-12 bpm individual error.

Newton's laws applied: force = mass x acceleration; ground reaction force equals body weight at standing and can exceed 2-5 body weights in landing and sprinting.

Torque (moment) = force x perpendicular moment arm; joint torque is the product of muscle force and its internal moment arm, which changes with joint angle.

Linear kinematics: displacement, velocity, acceleration; projectile range is maximized near a 45-degree release angle in a vacuum, lowered to ~30-40 degrees when release height and air drag are considered.

Angular kinematics: angular velocity = angular displacement / time; tangential velocity = angular velocity x radius, so longer limbs or implement radii raise endpoint speed.

Moment of inertia (I) and angular momentum (H = I x omega) are conserved in flight; a diver or gymnast tucks to reduce I and increase spin rate, then extends to slow rotation.

Impulse-momentum: impulse (force x time) equals change in momentum; follow-through lengthens contact time to increase implement velocity, while landing mats lengthen time to reduce peak force.

Center of mass and base of support determine static stability; stability increases with a larger base, lower center of mass, and a center of mass projected inside the base.

Muscle moment-arm trade-off: a longer moment arm increases torque per unit force but reduces joint angular velocity for a given muscle shortening speed; joints are often designed near the optimum of this trade-off.

Fitts and Posner stages: cognitive (large errors, verbal cues), associative (refinement, fewer errors), autonomous (automatic, low attention demand); progression is not strictly linear.

Gentile's two-dimensional taxonomy: environmental context (closed vs open, stationary vs in-motion) crossed with action requirements (body orientation, object manipulation).

Motor learning is inferred from relatively permanent performance change; retention tests measure persistence and transfer tests measure adaptability, whereas practice performance alone can mislead.

Fitts' law: movement time increases with the log2 of the ratio of target distance to target width (index of difficulty); speed and accuracy trade off systematically.

Practice scheduling: blocked practice aids immediate performance, random/interleaved practice aids retention and transfer; contextual interference effect is stronger for skills with multiple variants.

Feedback: knowledge of results describes outcome, knowledge of performance describes movement quality; a bandwidth of about 10 percent error tolerance reduces dependence on external feedback.

Whole versus part practice: part practice suits serial tasks with low interdependence; whole practice suits highly coupled, fast, continuous tasks such as sprinting or cycling.

Specificity and transfer: practice conditions should approximate the target context; bilateral transfer is positive from the trained to untrained limb, especially for asymmetric skills.

Carbohydrate loading: 8-12 g/kg/day for 24-48 hours before endurance events above ~90 minutes; glycogen supercompensation can raise muscle glycogen substantially above normal.

Daily protein for athletes: 1.2-2.0 g/kg/day for most training; up to ~1.6-2.2 g/kg for strength athletes; distribute in ~0.25-0.3 g/kg doses every 3-4 hours to maximize muscle protein synthesis.

Fluid replacement: aim to limit body mass loss to under ~2 percent during exercise; sweat rate = (pre-weight - post-weight + fluid intake) / exercise time; sodium (~300-700 mg/L) aids retention in salty sweaters.

Energy availability = (energy intake - exercise energy expenditure) / fat-free mass; below ~30 kcal/kg FFM/day indicates low energy availability, linked to RED-S and impaired bone and hormone function.

Pre-event meal: 1-4 g/kg carbohydrate 1-4 hours before, low fat and fiber, familiar foods; 30-60 g carbohydrate per hour for events of 1-2.5 hours, up to ~90 g/hour with multiple transportable sugars.

Caffeine ergogenic dose is ~3-6 mg/kg taken ~60 minutes pre-exercise; higher doses do not reliably add benefit and increase side effects.

Creatine monohydrate: ~3-5 g/day maintenance or ~20 g/day loading for 5-7 days; increases phosphocreatine stores and benefits short high-intensity efforts, with weight gain from water retention.

Iron and vitamin D are the most common micronutrient concerns in athletes; ferritin screening is useful in endurance athletes, and vegetarians need attention to iron, B12, and protein quality.

FITT-VP framework: Frequency, Intensity, Time, Type, Volume, Progression; aerobic guidelines are 150-300 minutes/week moderate or 75-150 minutes/week vigorous plus 2+ days of resistance training.

ACSM push-up and curl-up tests use age- and sex-specific percentile norms; 1RM testing requires familiarization and is safest with 3-5 repetitions at 85-90 percent of estimated max.

Estimated 1RM (Epley): 1RM ≈ weight x (1 + reps/30); valid only for reps under about 10-12 and less accurate for trained lifters.

Progressive overload requires manipulation of load, volume, frequency, or density; the general adaptation syndrome model describes alarm, resistance, and exhaustion phases.

Periodization: linear (high volume/low intensity to low volume/high intensity), undulating (frequent variation), and block (focused mesocycles); deload weeks reduce volume to manage fatigue.

Intensity zones by percent 1RM: ~60-70 percent for muscular endurance, ~70-85 percent for hypertrophy, ~85-100 percent for maximal strength; power training often uses 30-60 percent with high velocity.

Warm-up structure: general aerobic component plus dynamic, movement-specific drills; static stretching before power activities can transiently reduce force output and should be limited.

Ratings of perceived exertion (Borg 6-20 or 0-10) and heart rate zones should be cross-checked; HR-based zones underestimate intensity in short intervals and in heat.

RICE is largely superseded by PEACE & LOVE (Protection, Elevation, Avoid anti-inflammatories, Compression, Education; Load, Optimism, Vascularization, Exercise) for soft-tissue injury management.

Concussion: suspect with headache, confusion, dizziness, nausea, or balance problems after head impact; remove from play immediately and follow a graduated return-to-sport protocol supervised by a clinician.

Rhabdomyolysis warning signs after extreme exertion: severe muscle pain, dark cola-colored urine, weakness; requires urgent medical evaluation, IV fluids, and monitoring for kidney injury.

Heat illness: heat cramps, heat syncope, heat exhaustion, and heat stroke (core temp typically above 40 C with CNS dysfunction) is a medical emergency requiring immediate cooling.

Exertional heat stroke treatment priority is rapid cooling (cold-water immersion) rather than transport; survival depends on cooling within roughly 30 minutes of collapse.

Anterior cruciate ligament injury prevention programs combine neuromuscular training, landing mechanics, plyometrics, and strength work; they reduce injury rates, especially in female athletes.

Overuse injuries follow the load-capacity model: injury risk rises when training load exceeds tissue capacity; the acute:chronic workload ratio is a monitoring heuristic, not a hard rule.

Emergency action plan elements: venue-specific access, communication, emergency equipment location, trained responders, and documented activation and rehearsal.

Self-determination theory: autonomous motivation is supported by competence, autonomy, and relatedness; controlled motivation predicts poorer long-term adherence.

Transtheoretical model stages: precontemplation, contemplation, preparation, action, maintenance (plus termination); interventions should match stage-specific processes of change.

Social cognitive theory: self-efficacy, outcome expectations, and observational learning drive behavior; mastery experiences are the strongest source of self-efficacy.

Self-efficacy is the strongest single predictor of exercise adoption and maintenance; four sources are mastery experiences, vicarious experience, verbal persuasion, and physiological states.

Behavior change techniques with good evidence include goal setting, self-monitoring, action planning, feedback on behavior, and social support; combining techniques outperforms single ones.

Intrinsic motivation (enjoyment, competence) predicts adherence better than extrinsic rewards; extrinsic rewards can undermine intrinsic motivation when perceived as controlling.

Exercise and mood: acute aerobic exercise reliably reduces state anxiety and improves affect; effect sizes are moderate, and the relationship with depression is supported but not a substitute for treatment.

Social ecological model levels: individual, interpersonal, organizational, community, and policy; interventions targeting multiple levels tend to produce larger and more sustained behavior change.