Infraspinatus

Definition

The infraspinatus is one of the four rotator cuff muscles. It lies on the posterior scapula below the scapular spine, originates in the infraspinous fossa and inserts on the greater tubercle of the humerus. The suprascapular nerve supplies it. Together with teres minor it externally rotates the humerus, while coordinated rotator-cuff contraction helps centre the humeral head in the glenoid.

NCBI Bookshelf · Infraspinatus anatomy · NCBI Bookshelf · Rotator cuff anatomy

HYROX^® context

Wall balls, rowing, sled pulling and farmers carries involve the shoulder in different ways, but the current HYROX^® rules do not establish the infraspinatus as the essential limiter, show that it retracts the shoulder during rowing, or prove that its endurance prevents compensation, pain or “impingement.” Those outcome claims would require task-specific biomechanical and prospective evidence.

HYROX^® Singles Rulebook 2026/27 · NCBI Bookshelf · Rotator cuff anatomy

Exercise and shoulder symptoms

Side-lying external rotation, bands and cable exercises can train external rotation, but no exercise isolates only the infraspinatus and the sources reviewed here do not establish universal sets, repetitions or three-to-four-times-weekly frequency. A 2026 review found exercise may help rotator cuff-related shoulder pain, but interventions were heterogeneous, certainty was low and no approach was clearly most effective. Shoulder pain has multiple possible causes; weakness can be a clinical finding and does not by itself prove that a weak infraspinatus caused pain.

2026 systematic review · Exercise for rotator cuff-related shoulder pain · NCBI Bookshelf · Infraspinatus anatomy

Related terms

The infraspinatus belongs to the rotator cuff with supraspinatus, teres minor and subscapularis. The deltoids and serratus anterior have distinct roles in shoulder motion.

NCBI Bookshelf · Rotator cuff anatomy

Repz can help you correlate shoulder discomfort patterns with specific station demands.

FAQ

Can infraspinatus weakness cause shoulder pain in HYROX^®?

Weak external rotation may occur with several shoulder or nerve conditions, but weakness alone does not establish the cause of pain. Persistent pain or loss of strength warrants qualified assessment.

NCBI Bookshelf · Infraspinatus anatomy · NCBI Bookshelf · Rotator cuff anatomy · 2026 systematic review · Exercise for rotator cuff-related shoulder pain

How often should I train the infraspinatus?

No universal frequency is established. Choose external-rotation work, load and frequency within the complete programme according to goals, tolerance and any clinical guidance.

NCBI Bookshelf · Infraspinatus anatomy · NCBI Bookshelf · Rotator cuff anatomy · 2026 systematic review · Exercise for rotator cuff-related shoulder pain