Chest Anatomy for Weightlifting

The chest muscles play a vital role in upper body strength and pushing movements. Whether
you’re performing a bench press, a push-up, or a dumbbell fly, the muscles of the chest
contribute to force production, stabilization, and movement efficiency.

There are two primary types of movements used to train the chest:

• Pressing Movements – These involve pushing resistance away from the body (e.g.,

bench press, push-ups).

• Fly Movements – These involve bringing the arms toward the midline of the body in a

hugging motion (e.g., chest fly, cable crossover).

Both movements are essential for balanced chest development and ensuring strength across
different ranges of motion.

The chest is primarily made up of two muscles:

• Pectoralis Major – The large, fan-shaped muscle that covers most of the chest and is

responsible for pressing and arm movement.

• Pectoralis Minor – A smaller muscle located underneath the pec major that helps with

scapular movement.

Supporting muscles also play a role in chest exercises:

• Serratus Anterior – Assists in scapular stability, especially in pressing movements.
  ●  Anterior Deltoid – Assists the pec major in pushing movements.

Pectoralis Major

The pec major is the dominant chest muscle involved in pressing and fly movements.

• Structure & Function:
  ○  Origin:

■  Clavicular head – arises from the clavicle (collarbone).

■  Sternal head – arises from the sternum (breastbone) and upper ribs.

○

Insertion:

■  Humerus (upper arm bone).
○  Primary Actions in Weightlifting:

■  Horizontal adduction – Bringing the arms across the body (e.g., chest

fly).

■  Shoulder flexion – Raising the arm forward (clavicular head).
■  Shoulder adduction – Bringing the arm down toward the body (sternal

head).
●  Exercises that Target the Pec Major:

○  Clavicular head (upper chest): Incline bench press, incline dumbbell press,

incline fly.

○  Sternal head (mid/lower chest): Flat bench press, dips, push-ups.

Pectoralis Minor

The pec minor is located beneath the pec major and helps with scapular movement.

• Primary Functions:

○  Stabilizes and depresses the scapula.
○  Assists in shoulder blade protraction.

• Exercises that Engage the Pec Minor:

○  Dips
○  Push-ups
○  Decline presses

Supporting Muscles in Chest Training

While the pecs do most of the work, these muscles assist chest movements:

Serratus Anterior (“Boxer’s Muscle”)

• Located along the ribcage and helps stabilize the scapula
  ●  Primary Actions:

○  Protracts the scapula (pushes shoulder blades forward)
○  Works during pressing and pushing movements

• Exercises to Strengthen:

○  Push-ups (especially plus push-ups where you protract at the top)
○  Dumbbell pullovers
○  Landmine presses

Anterior Deltoid (Front Shoulder)

• Assists in pressing movements (bench press, push-ups, dips)
  ●  Becomes more dominant if chest engagement is weak
• Exercises that Involve the Anterior Deltoid:

○  Shoulder press
○  Close-grip bench press
○  Dips

Common Muscle Imbalances & How to Fix Them

Issue: Overactive Shoulders in Chest Movements

• Cause: Weak pec activation, leading to anterior delts taking over
  ●  Fix: Focus on mind-muscle connection, slow negatives, and pauses at the bottom

Issue: Weak Lower Chest Leading to Poor Pressing Power

• Cause: Imbalance between upper and lower pec development
  ●  Fix: Incorporate dips and decline presses

Issue: Tight Pec Minor Causing Rounded Shoulders

• Cause: Poor posture, excessive pressing without back training
  ●  Fix: Stretch pec minor, strengthen upper back (face pulls, reverse flys)

Application to Weightlifting

Exercise

Primary Chest Target

Key Cue for Maximum Engagement

Flat Bench Press  Mid/Lower Chest

Squeeze the pecs, retract shoulder blades, control
descent

Incline Bench
Press

Decline Bench
Press

Dips

Upper Chest

Lower Chest

Lower Chest & Pec
Minor

Slight arch, drive through upper pecs, don’t let shoulders
take over

Keep elbows slightly tucked, feel the stretch at the
bottom

Lean forward slightly, go deep but not too deep

Chest Fly

Full Pec Stretch

Keep a slight bend in elbows, focus on the
stretch/contraction

• Scapular Control & Stability (important for presses)

📝 Why is this important?

• The pectoralis major doesn’t directly move in this plane, but scapular control and shoulder

stabilization are crucial for safe pressing movements.

1. C) Transverse Plane (Rotational & Horizontal Movements)

Definition: The transverse plane divides the body into top and bottom halves.

• Movements in this plane happen horizontally or rotationally.
  ●  Joint Actions: Horizontal Adduction & Abduction

✔ Chest Movements in the Transverse Plane:

• Bench Press (Flat, Incline, Decline) → Shoulder Horizontal Adduction
  ●  Chest Flys (Dumbbells, Cables, Machine) → Shoulder Horizontal Adduction
  ●  Cable Crossovers (same pattern with different resistance angles)

📝 Why is this important?

• Most chest exercises fall into the transverse plane because the pectoralis major’s main function is horizontal adduction (bringing the arms across the body).

🟥 Transverse Plane (Main Chest Plane)
✔ Bench Press
✔ Dumbbell Fly
✔ Cable Crossover

🟦 Sagittal Plane (Upper Chest & Shoulder Flexion)
✔ Incline Press
✔ Dips
✔ Dumbbell Pullover

🟩 Frontal Plane (Not Much Direct Chest Movement)
✔ Some stabilization in pressing movements
✔ Dumbbell Pullover (partial frontal plane movement)

🔹 Exercise Selection Based on Planes

• Want to grow the overall chest? Focus on transverse plane movements like bench press and

flys.

• Want to target the upper chest? Use sagittal plane movements like incline presses and dips.
  ●  Want to avoid injury? Ensure scapular control and stability in all planes (especially frontal plane stabilization).

🔹 Avoiding Compensations & Mistakes

• Some people flare their elbows too wide during pressing, shifting movement toward the frontal

plane, which can stress the shoulders.

• Proper shoulder and scapular positioning keeps pressing efficient and safe within the

transverse plane.

Plane

Movement Direction

Joint Actions

Chest Exercises

Sagittal

Forward & Back

Flexion / Extension

Incline Press, Dips, Pullover

Frontal

Side-to-Side

Abduction /
Adduction

Some stabilization, Pullover

Transverse

Rotational /
Horizontal

Horizontal Adduction  Bench Press, Flys,

Crossovers

Upper Chest
(Clavicular Head of
Pec Major)

Incline Bench Press (Barbell/Dumbbell), Incline Dumbbell
Fly, Low-to-High Cable Fly, Incline Machine Press, Landmine Press

Middle Chest
(Sternal Head of Pec Major)

Flat Bench Press (Barbell/Dumbbell), Push-Ups, Chest
Press Machine, Flat Dumbbell Fly, Pec Deck Machine

Lower Chest (Lower
Sternal Fibers)

Decline Bench Press (Barbell/Dumbbell), Dips (Chest
Focused), High-to-Low Cable Fly, Decline Dumbbell Fly

Inner Chest (Sternal Head Emphasis)

Close-Grip Bench Press, Squeeze Press (Dumbbells
Pressed Together), Cable Crossover (Midline Emphasis),
Diamond Push-Ups, Pec Deck Machine (Full Squeeze)

Outer Chest
(Stretch-Focused
Movements)

Wide-Grip Bench Press, Wide-Grip Push-Ups, Dumbbell Fly
(Deep Stretch), Cable Fly (Full Range of Motion), Ring Push-Ups

This breakdown helps lifters understand how to strategically train different areas of the chest for balanced development. Let me know if you’d like any modifications or
additions!

Chest Exercise Categorization

Upper Chest (Clavicular Head of Pec Major)

Incline Bench Press (Barbell/Dumbbell)
● Incline Dumbbell Fly
●  Low-to-High Cable Fly
● Incline Machine Press
●  Landmine Press

Middle Chest (Sternal Head of Pec Major)

• Flat Bench Press (Barbell/Dumbbell)
  ●  Push-Ups
  ●  Chest Press Machine
  ●  Flat Dumbbell Fly
  ●  Pec Deck Machine

Lower Chest (Lower Sternal Fibers)

• Decline Bench Press (Barbell/Dumbbell)
  ●  Dips (Chest Focused)
  ●  High-to-Low Cable Fly
  ●  Decline Dumbbell Fly

Inner Chest (Sternal Head Emphasis)

• Close-Grip Bench Press
  ●  Squeeze Press (Dumbbells Pressed Together)
  ●  Cable Crossover (Midline Emphasis)
  ●  Diamond Push-Ups
  ●  Pec Deck Machine (Full Squeeze)

Outer Chest (Stretch-Focused Movements)

• Wide-Grip Bench Press
  ●  Wide-Grip Push-Ups
  ●  Dumbbell Fly (Deep Stretch)
  ●  Cable Fly (Full Range of Motion)
  ●  Ring Push-Ups

Planes of Motion for Chest Exercises: Clarifying the Debate

Understanding Chest Movements Across Different Planes

The chest primarily functions in the transverse plane, but some movements,
particularly upper chest-focused exercises, also involve the sagittal plane.
Understanding these differences helps with proper exercise selection and cueing.

💡 There is ongoing debate regarding whether pressing movements, like the bench
press, should be classified strictly in the transverse plane or if they also involve
elements of the sagittal plane due to the elbow extending forward. Different sources and
institutions, including NASM, primarily categorize bench pressing as a transverse plane
movement, while others consider the pressing motion itself to have sagittal plane
characteristics. This course presents both viewpoints to help lifters and trainers develop
a comprehensive understanding.

🟥 Transverse Plane – Primary Plane for Chest Presses & Flies

• The transverse plane involves movements where the arms move across the

body, such as horizontal adduction of the shoulder joint.

• Chest exercises in the transverse plane:

○  Flat Bench Press (Barbell & Dumbbell)
○  Decline Bench Press
○  Dumbbell Fly
○  Cable Crossovers

🟦 Sagittal Plane – Upper Chest & Shoulder Flexion Movements

• The sagittal plane involves shoulder flexion, where the arm moves forward,

lifting in front of the body.

• Chest exercises in the sagittal plane:

○

Incline Press (Barbell & Dumbbell) – More shoulder flexion compared to
flat and decline presses

○  Dips – Shoulder flexion is a key movement when pushing up
○  Dumbbell Pullover – Moves through both sagittal and frontal planes

🟩 Frontal Plane – Limited Chest Contribution

• The frontal plane involves side-to-side motion, which isn’t a primary function of

the chest, but some chest exercises involve elements of it.

• Movements with frontal plane involvement:

○  Dumbbell Pullover – Includes some motion in the frontal plane
○  Pressing Movements – Some stabilization demands in the frontal plane

Summary for Course Inclusion

• Bench presses and flies are generally transverse plane movements, due to
•  

horizontal adduction of the shoulder.
Incline presses and dips involve sagittal plane movement, as they require
greater shoulder flexion.

• Pullovers involve both sagittal and frontal planes, depending on the range of motion and execution.

This explanation aligns with scientific and practical perspectives while addressing why
some view pressing movements differently.

• Primary Muscles Targeted: Pectoralis Major
• Secondary Muscles: Anterior Deltoid, Biceps Brachii (short head)
• Prime Mover: Pectoralis Major
• Synergists: Anterior Deltoid, Biceps Brachii (short head)
• Stabilizers: Rotator Cuff, Core
• Concentric (Lifting):

○  Elbow: Slight Extension (triceps maintain stability but don’t fully straighten)

○  Shoulder: Horizontal Adduction (pecs bring arms together)

• Eccentric (Lowering):

○  Elbow: Slight Flexion (arms stay slightly bent)
○  Shoulder: Horizontal Abduction (arms open outward)

• Primary Muscles Targeted: Pectoralis Major
• Secondary Muscles: Anterior Deltoid, Biceps Brachii (short head)
• Prime Mover: Pectoralis Major
• Synergists: Anterior Deltoid, Biceps Brachii (short head)
• Stabilizers: Rotator Cuff, Core
• Concentric (Pulling Handles Together):

○  Elbow: Slight Extension (minimal movement)
○  Shoulder: Horizontal Adduction (arms come across the body)

• Eccentric (Returning to Start):

○  Elbow: Slight Flexion (remains mostly fixed)
○  Shoulder: Horizontal Abduction (arms open outward)

6. Dips (Chest Emphasis)

• Primary Muscles Targeted: Pectoralis Major (Lower Fibers), Triceps Brachii
• Secondary Muscles: Anterior Deltoid
• Prime Mover: Pectoralis Major (Lower Fibers)
• Synergists: Anterior Deltoid, Triceps Brachii
• Stabilizers: Rotator Cuff, Core
• Concentric (Pushing Up):

○  Elbow: Extension (triceps straighten the arms)
○  Shoulder: Flexion (pecs and delts move arms forward)

• Eccentric (Lowering Down):

○  Elbow: Flexion (elbows bend)
○  Shoulder: Extension (arms move behind the body)

7. Dumbbell Pullover

• Primary Muscles Targeted: Pectoralis Major, Latissimus Dorsi
• Secondary Muscles: Triceps Brachii (long head), Serratus Anterior
• Prime Mover: Pectoralis Major, Latissimus Dorsi
• Synergists: Triceps Brachii (long head), Serratus Anterior
• Stabilizers: Rotator Cuff, Core
• Concentric (Lifting Dumbbell Overhead to Chest):

○  Elbow: Slight Flexion (triceps maintain stability)
○  Shoulder: Extension (lats and pecs pull the weight forward)

• Eccentric (Lowering Dumbbell Backward):

○  Elbow: Slight Extension (arms stay slightly bent)
○  Shoulder: Flexion (arms move overhead and back)