DIPLO ENTRENADOR PERS 2026 MOD3 CLASE 1 VIDEO 1

Main ideas & lessons (organized by section)

1) Class logistics and purpose

• The session begins with the instructor/coordinator explaining:
  • Breaks will occur when the speaker indicates.
  • Attendees can post questions in chat; microphones should stay muted unless the speaker asks otherwise.
• The speaker’s credentials and focus:
  • Dr. Wilbert Núñez introduces himself (medical doctor; anatomy instructor; certified coaching staff; founder of projects).
  • The module is “Anatomy, Physiology and Biomechanics” (Personal Training, Module 3).

2) Module outline (topics covered in the lesson)

Dr. Núñez states the module topics include:

• Fundamentals of anatomy
• Macro anatomy and microscopic muscle physiology of muscle contraction
• Systems energy in training
• Physiological properties of muscle (four properties mentioned)
• Muscle fibers
• Muscle classification
  • skeletal classification, location, action
  • types of muscle actions
  • training effects/adaptations
• Biomechanical concepts (lever, moment arm, torque, etc.)

---

3) Anatomy fundamentals: key concepts and definitions

Anatomy definition and word roots

• Anatomy is presented as a branch of biology studying:
  • structures of the human body
  • how structures relate to each other
  • shapes and characteristics
• Etymology:
  • “ana-” relates to separating/upward
  • “-tomy” relates to cutting/dissection
• Anatomical study is introduced as historically dissection-based.

Anatomical position

A reference posture for describing all body parts:

• standing upright, facing forward
• palms facing forward
• arms at sides, forehead up

Anatomical orientations (directional terms)

• Superior / cephalic: closer to the head
• Inferior / caudal: closer to the feet
• Medial: closer to the midline
• Lateral: farther from the midline (also said as “external”)
• Anterior / ventral: closer to the front
• Posterior / dorsal: closer to the back
• Proximal: nearer the origin/root of a limb
• Distal: farther from the origin/root
• Deep / superficial
  • deep: farther from the skin surface
  • superficial: closer to the skin surface

Anatomical planes (3)

• Sagittal plane: divides body into left/right
• Transverse (horizontal) plane: divides upper/lower (used depending on movement axis)
• Frontal (coronal) plane: divides anterior/posterior (described as crown-like)

Anatomical axes (3)

• Longitudinal axis: top to bottom (rotation occurs around it)
• Transverse axis: side-to-side
• Sagittal/anterior-posterior axis: front-to-back

Basic joint movements and how to map them

Movements are described as displacements relative to anatomical position, occurring in specific planes around specific axes.

• Flexion / extension
  • flexion: decreases the joint angle (shortens the joint angle)
  • extension: increases the joint angle
  • occurs in the sagittal plane around the relevant axis (elbow example mentioned)
• Abduction / adduction (separation/approach)
  • abduction ≈ separation
  • adduction ≈ approximation
  • occurs in the transverse/coronal plane around the appropriate axis
• Rotation
  • external/internal rotation around the longitudinal axis
  • occurs in the horizontal/transverse plane
• Special/other named motions
  • circumduction (combined movement; not always possible in every joint)
  • pronation/supination (forearm rotation; palm down vs palm up)
  • dorsiflexion/plantar flexion (foot)
  • version/inversion (foot movements described as separation/approach)
  • retraction/protraction and scapular movements
  • thumb opposition (mentioned)

Range of Motion (ROM)

• ROM definition: limit of movement around a joint, described in degrees.
• Active vs passive ROM
  • Active: performed by the person (strength, neuromuscular function, pain, nerve activation, etc.)
  • Passive: external force moves the limb (assesses joint capsule/ligaments/structural limitations, not strength)
• Training ROM types
  • Full ROM
  • Partial ROM, subdivided:
    • Shortened partial range (more limited range where the muscle is more shortened)
    • Lengthened partial range (“stretched” portion)
• Hypertrophy debate mentioned
  • lengthened partials may be advantageous for hypertrophy compared to full ROM (as presented)
  • shortened partials may offer strength advantages but possibly less hypertrophy benefit (depending on training to failure and other conditions)

---

4) Muscle structure: from macro to micro

Macro anatomy (skeletal muscle)

• Approximate composition:
  • ~75% water
  • ~20% proteins (myosin/thick and actin/thin are major proteins)
  • ~5% mineral salts and other components
• Gross structure:
  • muscle belly (fleshy central portion)
  • tendons at ends (connective tissue; proximal/distal attachments)
• Basic function concept:
  • muscles contract to mobilize body segments by shortening between attachment points

Microscopic organization (functional units)

Hierarchical organization:

1. Myocyte (muscle fiber cell)
2. Muscle fiber
3. Myofibril
4. Myofilaments
   • actin (thin filament)
   • myosin (thick filament)
5. Sarcomere
   • unit functional for contraction

Muscle connective tissue “wrappings” (organization & names)

• Endomysium: around individual fibers
• Perimysium: around fascicles
• Epimysium: around the whole muscle These connective layers support organization and force transmission to tendons.

Myocyte organelles relevant to contraction

• Sarcoplasmic reticulum (SR) (smooth endoplasmic reticulum in muscle)
• Main claim emphasized:
  • SR stores calcium
  • calcium is released when the muscle depolarizes via stimulus-driven steps
  • SR calcium is held by a sequestration protein (named as calsequestrin)

---

5) Muscle contraction physiology (cross-bridge cycle)

Core mechanism taught

• Actin binding sites are blocked by regulatory proteins:
  • tropomyosin covers active sites
  • troponin acts as a regulatory “lock”
• Calcium’s role:
  • calcium binds to troponin → troponin “opens”/repositions regulation → tropomyosin shifts → myosin can bind actin

Cross-bridge sequence (conceptual cycle)

• myosin binds actin strongly when sites are exposed
• ATP is required
• ATP binding to myosin reduces affinity → myosin detaches
• ATP hydrolysis provides energy → myosin resets (“stands up”) to rebind actin
• repeating thousands/millions of times produces shortening and force

Visualization detail (sarcomere states)

• relaxed sarcomere: distinct bands/stripes
• contracted state: myosin pulling toward the M-line and sarcomere shortening

Control via nervous system (neurotransmission)

• Brain/spinal cord signals travel via nerves
• Presynaptic terminal releases acetylcholine
• Acetylcholine allows sodium entry → depolarization → triggers calcium release → contraction via the sarcomere cycle

---

6) Energy systems for training (ATP production)

ATP and its limited stores

• ATP is necessary for contraction; muscle has limited ATP quantity.

Main systems

• Anaerobic (no oxygen)
  • Phosphagen system / phosphagen-alactic
    • very fast ATP generation
    • supports explosive efforts (e.g., “one rep” type intensity; very short duration)
  • Anaerobic glycolytic system (lactic)
    • fast but shorter duration (up to ~2 minutes stated)
    • produces lactic acid, lowering pH → contributes to fatigue until cleared
• Aerobic (with oxygen)
  • slower ATP generation
  • more sustained (described as long-duration/indefinite)
  • depends on oxygen use in mitochondria and substrates (glucose/fats; proteins mentioned as possible)

Continuum concept

• Systems overlap rather than act in isolation:
  • walking: mostly aerobic
  • sudden sprint/jump: recruits glycolytic and phosphagen when intensity spikes
  • steady movement again: aerobic dominance returns

Creatine (supplement note) and timing

• Creatine/phosphocreatine role:
  • stores phosphate to rapidly regenerate ATP
• Claim included:
  • creatine can help explosive power athletes
• Saturation time noted (~30 days; ~5g/day mentioned)
• Possible GI discomfort with certain loading strategies

Rigor mortis (curiosity / physiology application)

• After death:
  • rigidity occurs due to cessation of ATP production
  • myosin remains bound to actin without ATP release/detachment
• Mechanism described as involving calcium handling and loss of regulatory reset
• Also linked to meat aging:
  • animals become stiff during rigor, then tenderize later via enzymatic decomposition

---

7) Physiological properties of muscle (4 properties listed)

• Excitability
• Contractility
• Extensibility
• Elasticity
  • elasticity linked to titin as a key contributor (spring-like behavior)

---

8) Muscle fiber types (slow/fast continuum)

• Type I (slow oxidative / red fibers)
  • high myoglobin → red appearance
  • suited for endurance/aerobic-type activity
• Type 2A (intermediate / rapid oxidative / glycolytic mix)
  • intermediate behavior
  • used in shorter, intense efforts (example: ~400m-type duration)
• Type 2B (fast glycolytic fibers)
  • greatest force/speed emphasis
  • larger fibers; explosive sports context
• The talk emphasizes:
  • fiber distribution tends to be a continuum shaped by genetics and training adaptations

---

9) Muscle contraction types and biomechanics at the micro/contractile level

Isometric vs isotonic vs eccentric vs concentric

• Isometric: muscle length does not change while producing force
  • example: wall push, holding weight in place
• Isotonic: muscle length changes while tension remains similar
  • Concentric (positive): shortening while lifting
  • Eccentric (negative): lengthening while resisting (lowering under control)
• Training insight:
  • eccentric often feels/permits greater strength (about a ~30% claim stated)

---

10) Effects and adaptations of training (acute vs chronic)

Acute (immediate) effects

• Increased heart rate and cardiac output
• Increased respiratory rate/ventilation
• Increased metabolic byproducts like lactate (when anaerobic work is involved)
• Increased fat oxidation noted as part of aerobic patterns

Chronic adaptations (long-term)

• Increased VO2max
• Lower resting heart rate (efficiency)
• Increased mitochondrial density
• Lower blood pressure over time (presented as clinically meaningful)
• Improved glycemic control / diabetes risk reduction
• Favorable body composition:
  • reduced fat percentage and visceral fat mentioned
• Resistance training adaptations:
  • strength and power increases
  • hypertrophy (sarcoplasmic vs myofibrillar hypertrophy mentioned)
  • early neuromuscular adaptations (“gains” when starting)

Muscle “memory” / recovery after stopping

• Hypertrophy depends on muscle fiber nuclei (satellite cells merging nuclei into fiber)
• Claim:
  • nuclei generally persist, making it easier to regain after time off than to start from scratch

---

11) Biomechanical concepts (lever, moment arm, torque)

Biomechanics definition

• Application of mechanics/physics to living structures (human body).

Lever

• A lever is a rigid bar with a fulcrum (pivot/support)
• Requires:
  • power (applied force)
  • resistance/load (to overcome)
• Lever classes (based on fulcrum position):
  • First class: fulcrum between power and resistance (example: head/spine with trapezius idea)
  • Second class: resistance in center (example: wheelbarrow/heel raise idea)
  • Third class: power in center (example: biceps brachii)

Moment arm (arm of moment)

• Perpendicular distance from axis of rotation to the line of action of resistance
• In exercises, moment arm changes through the range of motion:
  • larger at certain joint angles (e.g., ~90° in a biceps curl example)
  • smaller at others

Torque / moment of force

• Presented as: Torque = resistance × moment arm

• Emphasis:

  • similar perceived torque can occur with different loads depending on geometry (distance/moment arm), meaning difficulty depends on both weight and mechanics.

---

12) Skeletal muscle classification and location (macro-level anatomy applied)

Classification by fiber arrangement (“shape by tendon insertion”)

• Parallel
  • fusiform (spindle-shaped)
• Convergent
  • triangular examples
• Circular
  • orbicular muscles examples
• Pennate
  • single pennate, double/multiple pennate (feather-like insertion)

Additional classification by:

• fiber direction (straight vs oblique vs transverse)
• number of heads (mono-, bi-, tri-, quadri-head examples)
• action (flexors, extensors, abductors, pronators, etc.)
• contribution (agonist, antagonist, synergist/fixator)
• number of joints (monoarticular/biarticular/triarticular/multiarticular)
  • biceps brachii described as triarticular

Classification by location (named regions)

Examples provided:

• brachial (arm), femoral (thigh), pectoral (chest)
• additional named regions (e.g., scapular/humeral, etc.)

---

13) Practical anatomy examples (head/neck/trunk/appendages)

Head and neck

• Facial muscles and chewing muscles introduced.
• Botulinum toxin mentioned as an aesthetic mechanism:
  • blocks acetylcholine release at nerve terminals → reduces forehead muscle activation
• Neck muscles:
  • functional roles (turning head, flexion)
  • aesthetic/clinical context:
    • neck circumference thresholds linked to obstructive sleep apnea risk (numbers given for men/women)

Trunk

• Trunk muscles grouped into:
  • posterior wall
  • anterolateral thorax
  • anterolateral abdominal wall
  • diaphragm (unique group)
  • pelvic floor (perineum)
• Rectus abdominis and abdominal wall:
  • aesthetic visibility tied to body fat level
  • functional role in intra-abdominal pressure and stabilization
• Core training nuance:
  • abdominal movements must match the real action (hip flexion vs true pelvic motion discussed)
  • isometric anti-rotation exercises recommended for stability and some lumbar-injury contexts (with caveats on load/reps in pathology)
• Nutrition emphasis:
  • visible “squares” require a calorie deficit/body fat reduction; training alone won’t reveal them without it

Appendicular skeleton: upper limb and lower limb overview

• Upper limb segments
  • shoulder skeleton (scapula, clavicle)
  • arm (humerus)
  • forearm (radius/ulna)
  • hand (carpals, metacarpals, phalanges)
• Rotator cuff
  • supraspinatus, infraspinatus, teres minor, subscapularis
  • stabilization role and injury susceptibility (supraspinatus emphasized)
• Arm muscle actions:
  • triceps: extension; long head crosses shoulder
  • biceps and brachialis: flexion; biceps also supination (as described)
• Lower limb segments
  • pelvic girdle, femur, tibia/fibula, tarsus/foot bones
• Hip and thigh major groups reviewed:
  • iliopsoas: hip flexion
  • gluteal region: hip extension and power emphasis
  • quadriceps: knee extension and hip flexion contribution (rectus femoris emphasized as biarticular)
  • hamstrings: knee flexion and hip extension contribution

Calf and foot muscles

• Calf:
  • gastrocnemius + soleus and relationship to the Achilles tendon
  • genetic component discussed for calf development
• Foot:
  • intrinsic/extrinsic organization mentioned
  • movements/actions like dorsiflexion/plantar flexion and fine movements

---

14) Didactic evaluation (quiz summary at the end)

A short “rapid assessment” asked about:

• sagittal plane definition
• movement around an anterior-posterior axis (abduction/adduction referenced in attempted answers)
• organization/structure of skeletal muscle
• connective tissue naming around fascicles
• actin/myosin filaments
• muscle fiber properties (excitability, contractility, extensibility, elasticity)
• fiber type classification (Type I)
• muscle naming by number of heads
• diaphragm identification
• biceps femoris location
• contraction type definition (isometric)
• torque formula concept (resistance × moment arm)
• whether aerobic vs anaerobic benefit should be placed in chat (responses suggested cardiovascular improvement)

---

Speakers / sources featured

• Dr. Wilbert Núñez (primary speaker; medical doctor; anatomy instructor; presented the content)
• Coordinator / host (unnamed) (gave opening instructions about chat/questions and managed session flow; specific name not clearly stated)

Mentioned but not as speakers in the video recording

• Luis Fajardo (asked a question in chat; referenced by name)
• Carlos Durán (chat question; referenced by name)
• Axel V (asked/posed questions in chat; referenced by name)
• Alberto Cardona (chat participant; referenced by name)
• Esmeralda