1. Quadriceps (Front Thigh Muscles)

• Origin: Femur and Ilium (hip)
• Insertion: Patella (kneecap) and Tibia
• Function: Knee extension
  • Important for: Squats, leg press, lunges

2. Hamstrings (Back Thigh Muscles)

• Origin: Femur and Ischium (pelvis)
• Insertion: Tibia and Fibula
• Function: Knee flexion and hip extension
  • Important for: Deadlifts, leg curls

3. Gluteus Maximus (Glutes)

• Origin: Ilium (hip), Sacrum, Coccyx (tailbone)
• Insertion: Femur, hip ligaments
• Function: Hip extension, abduction, and external rotation
  • Important for: Squats, lunges, hip thrusts

4. Latissimus Dorsi (Lats)

• Origin: Spine (T7-L5), Sacrum, Iliac crest
• Insertion: Humerus (upper arm)
• Function: Arm adduction, internal rotation, and extension
  • Important for: Pull-ups, lat pulldowns, rowing

5. Pectoralis Major (Chest)

• Origin: Clavicle, Sternum, Ribs
• Insertion: Humerus
• Function: Arm adduction, flexion, and internal rotation
  • Important for: Bench press, push-ups, chest flys