ACSM-EP Musculoskeletal Anatomy 4 — Questions and Answers
Question 1: During a squat, the eccentric phase primarily loads which muscle group?
- Hip flexors and ankle dorsiflexors
- Quadriceps and gluteus maximus (Correct answer)
- Hamstrings and hip adductors
- Gastrocnemius and tibialis anterior
Correct answer: Quadriceps and gluteus maximus
During the eccentric (lowering) phase of a squat, the quadriceps and gluteus maximus lengthen under load to control knee and hip flexion.
Question 2: The carpal tunnel is bounded superiorly by the flexor retinaculum and contains which nerve?
- Ulnar nerve
- Radial nerve
- Median nerve (Correct answer)
- Musculocutaneous nerve
Correct answer: Median nerve
The carpal tunnel contains the median nerve and the flexor tendons; compression of the median nerve causes carpal tunnel syndrome.
Question 3: Which muscle group is primarily responsible for scapular upward rotation during overhead pressing?
- Rhomboids and levator scapulae
- Serratus anterior and upper/lower trapezius (Correct answer)
- Pectoralis minor and subclavius
- Infraspinatus and teres minor
Correct answer: Serratus anterior and upper/lower trapezius
Scapular upward rotation is a force couple produced by the serratus anterior and the upper and lower trapezius, essential for full overhead mobility.
Question 4: The lateral longitudinal arch of the foot is supported primarily by which bone?
- Navicular
- Cuboid (Correct answer)
- Medial cuneiform
- Talus
Correct answer: Cuboid
The lateral longitudinal arch runs from the calcaneus to the fifth metatarsal and is supported primarily by the cuboid bone.
Question 5: Which type of muscle fiber has the highest oxidative capacity and is most fatigue-resistant?
- Type IIx
- Type IIa
- Type I (Correct answer)
- Type IIb
Correct answer: Type I
Type I (slow-twitch) fibers have the highest oxidative capacity, greatest mitochondrial density, and are the most fatigue-resistant, making them ideal for endurance activities.
Question 6: The thoracolumbar fascia connects which two important structures relevant to lumbar stability?
- Scapula and pelvis
- Latissimus dorsi and gluteus maximus via the posterior layer (Correct answer)
- Quadratus lumborum and psoas major
- Erector spinae and multifidus only
Correct answer: Latissimus dorsi and gluteus maximus via the posterior layer
The posterior layer of the thoracolumbar fascia creates a mechanical link between the latissimus dorsi and contralateral gluteus maximus, contributing to load transfer across the lumbar spine.
Question 7: Which structure separates the medial and lateral compartments of the knee and acts as a shock absorber?
- Patellar tendon
- Bursa
- Meniscus (Correct answer)
- Articular cartilage
Correct answer: Meniscus
The medial and lateral menisci are fibrocartilaginous structures that deepen the tibial plateau, distribute load, and absorb shock within the knee joint.
ACSM-EP Musculoskeletal Anatomy 4
During a squat, the eccentric phase primarily loads which muscle group?