Band external rotation

Movement

What the movement is

External rotation means turning the arm outward. The infraspinatus mainly helps rotate the shoulder outward and raise the arm in the plane of the shoulder blade⁸. It is a thick, triangular muscle that fills much of the infraspinous fossa, the hollow on the back of the shoulder blade below its ridge⁸. The posterior deltoid draws the arm backward and also rotates it outward⁹.

A 2009 review lists external rotation at 0 and 90 degrees of abduction among exercises with high to very high activity¹⁰. Abduction means moving a limb away from the midline of the body, as when lifting the arm out to the side. Its list covered the rotator cuff, four muscles that cross the shoulder joint, plus the deltoids and shoulder-blade muscles¹⁰.

The versions studies have used

The studies on this page tested the exercise in several forms^1,11:

• Standing with the arm at the side, with or without a towel roll under the arm^1,12.
• Standing with the arm raised out to the side to 45 or 90 degrees¹³.
• Side-lying with the arm at the side¹⁴.
• Prone, meaning lying face-down, with the arm raised to 90 degrees¹.
• Sitting¹¹.
• Eccentric-focused, standing and side-lying, where the muscle works while it lengthens¹⁵.

What it loads

The rotator cuff

The rotator cuff is a ring of four tendons linking the shoulder blade to the upper arm bone¹⁷. They come from the subscapularis, supraspinatus, infraspinatus and teres minor, a small muscle below the infraspinatus¹⁷.

The rotator cuff works with neighbouring muscles to keep the unstable shoulder joint centred¹⁸. This stops the humerus, the upper arm bone, riding upward¹⁸.

In 13 healthy men doing standing external rotation, a moderate band raised supraspinatus and infraspinatus activity more than a light band¹³. Besides steadying the joint, the supraspinatus lifts the arm out to the side and may help weakly to turn it outward¹⁹.

Infraspinatus and teres minor: where studies disagree

Studies differ on which version works the infraspinatus hardest^1,11,14:

• In 10 healthy people across seven exercises, side-lying with the arm at the side drew the most infraspinatus activity, at 62% of maximum¹⁴.
• In 18 healthy men, infraspinatus activity and its ratio to posterior deltoid activity were higher prone and standing than side-lying and sitting¹¹.
• In 30 healthy people across five exercises, infraspinatus activity did not differ significantly between them¹.

The same 10-person study found side-lying drew the most teres minor activity, at 67% of maximum¹⁴. In 18 collegiate baseball players lying face-down under manual resistance, teres minor activity was lower than infraspinatus activity during external rotation²⁰.

In 20 healthy people, electrodes went into three regions of the infraspinatus¹⁶. The upper and middle regions were similarly active across arm positions in standing isometric external rotation¹⁶. The lower region was most active with the arm raised to 90 degrees¹⁶. The trapezius is the large muscle across the upper back and neck that moves the shoulder blade. In 15 healthy people doing eccentric-focused versions, the infraspinatus and lower trapezius were more active than the supraspinatus, upper trapezius and middle deltoid¹⁵.

Other muscles, version by version

The teres major is a thick shoulder muscle that runs from the shoulder blade to the upper arm bone. In 30 healthy people, four of the five versions each drew the most activity from a different set of muscles¹:

Version	Muscles most active of the five versions
Standing, arm raised to 90 degrees	Front and middle deltoid, supraspinatus, upper trapezius, serratus anterior (a muscle on the side of the chest)1
Prone, arm raised to 90 degrees	Lower trapezius, latissimus dorsi (broad back muscle), subscapularis, teres major1
Side-lying, towel under the arm	Posterior deltoid, middle trapezius, rhomboids (muscles between the shoulder blades and the spine)1
Standing, towel roll under the arm	Pectoralis major (the large chest muscle), both its collarbone and breastbone parts1

How arm angle shifts the work

In 10 healthy young adults tested at seven arm angles, raising the arm lowered infraspinatus activity and raised posterior deltoid activity². So the ratio of infraspinatus to posterior deltoid activity fell².

In 13 healthy men using a band, supraspinatus activity was higher at 45 and 90 degrees than with the arm at the side¹³. Upper trapezius and serratus anterior activity rose at 90 degrees¹³. In 20 healthy people, isometric external rotation drew more supraspinatus activity with the arm raised to the side than forward, especially at 90 degrees¹⁶.

In the 30-person study, posterior deltoid activity was significantly higher in three versions than standing, arm at the side, with or without a towel¹. Those three were prone at 90 degrees, side-lying, and standing at 90 degrees¹.

What the towel roll and posture change

In 20 men, a towel roll under the arm did not change infraspinatus activity, standing or side-lying¹². It raised posterior deltoid activity¹². It lowered middle deltoid activity side-lying, but not standing¹². The authors of the 10-person arm-angle study say raising the arm slightly, as a towel does, did not make the infraspinatus work more selectively². They add that it may help comfort².

In 15 healthy people doing band exercises, a slouched posture raised muscle activity and range of motion, meaning how far the joint moved²¹. Cueing a corrected posture made little difference compared with no cue²¹.

How load shifts the work

In 18 people with healthy shoulders, isometric loads of 10% to 40% of maximum gave the infraspinatus its largest share, with the least deltoid involvement³. In the same 18 people, squeezing the arm toward the body at low loads reduced middle deltoid involvement³. At low loads, the posterior deltoid worked alongside the infraspinatus, in parallel³.

In 15 healthy men, infraspinatus and posterior deltoid activity both rose with resistance²². The ratio of infraspinatus to posterior deltoid activity rose as resistance fell²². In 13 healthy men, posterior deltoid and upper trapezius activity rose with the heavier band¹³. Both stayed relatively low, at about 13% and 23% of maximum¹³.

In people with shoulder pain

In 14 people (18 shoulders) with painful subacromial impingement, isometric loads of 10% to 40% of maximum gave the infraspinatus its largest share²³. Higher loads drew more on the middle deltoid than on the infraspinatus²³.

A Dutch guideline defines subacromial pain syndrome as shoulder pain not from an injury or a rheumatic disease²⁴. It is especially painful when the arm is raised²⁴.

A systematic review searches for the research on a question in a set, checkable way. One systematic review of 22 papers compared shoulder muscle activity in people with and without the syndrome²⁵. For most muscles, it found no clear differences, whatever the task, load or arm position²⁵. There was limited evidence of lower serratus anterior activity in people with the condition²⁵.

How the body adapts

What training changed in strength

Training studies of this movement measured the shoulder’s turning force, called torque, with mixed results^4,5,26:

• In a randomised study of 40 young adults without shoulder injury, 8 weeks of band exercise raised maximal isometric outward-turning torque more than no training⁴. Torque was measured at 65 degrees of external rotation, and the programme also included internal rotation, turning the arm inward⁴.
• In 22 college tennis players, randomised to 4 weeks of rotator training or to no training, the trained group gained outward-turning torque at fast speed²⁶. It also gained serve speed; the training used elastic tubing and light dumbbells²⁶.
• In 20 untrained college-aged women, 4 weeks of heavy training with bands or with weights did not change outward-turning force significantly in either group⁵.

A team warm-up in handball

One trial of 660 elite handball players, randomised by team, tested a whole warm-up programme, not the exercise alone²⁷. Some teams used a warm-up aimed partly at outward-turning strength²⁷. Those teams had a 28% lower risk of shoulder problems over a season than control teams²⁷. Their 22% lower risk of substantial shoulder problems was not statistically significant²⁷.

Trials in people with shoulder conditions

Trials and reviews in people who already had shoulder pain gave mixed and often uncertain results^6,28,29. Tendinopathy is local pain in a tendon that comes with activities that load it. A meta-analysis pools the results of several studies; a network meta-analysis compares many options at once:

• Added external-rotation work. In a randomised trial of 200 people with long-standing subacromial impingement, one group added a large dose of shoulder strengthening to usual care⁶. Built mainly on external-rotation exercises, at 4 months it gave no better shoulder pain and disability scores than usual care alone⁶.
• Shoulder exercise in general. A network meta-analysis pooled 89 randomised trials in 5,532 adults with rotator cuff tendinopathy²⁸. Exercises for the shoulder muscles may have reduced pain and improved function compared with no intervention²⁸. The evidence was very uncertain²⁸.
• How much exercise. A systematic review found three randomised trials, with 283 people, comparing higher and lower exercise doses in rotator cuff tendinopathy²⁹. Their certainty was low to very low, and their results conflicted²⁹.
• Strength. A meta-analysis pooled 28 studies in people with shoulder pain related to the rotator cuff³⁰. Across the programmes studied, outward-turning strength rose by a moderate amount³⁰. Programmes with strength training or active exercises raised strength; those without exercise did not³⁰.

Progressive overload

A 2026 position stand describes progressive overload as the need to increase the stimulus placed on the muscle throughout a training programme³¹.

Raising the load

In an 8-week randomised study, adults aged 18 to 67 trained with elastic resistance, including external rotation with the elbow at the side³². One group moved to a shorter band or a new colour when an exercise was rated 2 or below for how hard it felt³². The other used a load cell, a device that measures force³². It added 1 to 2 pounds when all repetitions were done with correct form and without difficulty³². Gains in external-rotation strength did not differ between the two groups³².

In a randomised trial of 100 people with rotator cuff tendinopathy, one group did side-lying dumbbell external rotation with a rising load⁷. In week 1 it was the most they could lift 15 times; in weeks 9 to 12, the most they could lift 6 times⁷. The other group kept to 3 sets of 20 to 25 repetitions from week 1 to week 12⁷. The two programmes gave no significantly different disability, pain, range of motion or strength results⁷.

In the trial of 200 people with long-standing subacromial impingement, the added band programme was built mainly on external rotation⁶. It ran in 3 phases of 5 to 6 weeks, and each phase added one exercise and raised the load⁶. It prescribed about 12 hours of time under tension, how long a muscle works; sensors recorded an average of 2.9 hours⁶.

Lighter and slower

In a randomised study, 16 healthy men did side-lying dumbbell external rotation three times a week for 8 weeks³³. One group moved 500 g slowly; the other moved 2.5 kg at normal speed³³. Infraspinatus cross-sectional area, the size of a slice across the muscle, rose 7.3% in the slow group but not significantly in the other³³. The study found no significant differences in external-rotation strength³³.

Connections

The exercise works the muscles of the rotator cuff^13,17. The muscles it works include these:

• The infraspinatus, on the back of the shoulder blade^8,14.
• The teres minor, one of the four rotator cuff muscles^14,17.
• The supraspinatus, more so with the arm raised¹³.
• The deltoid, including its posterior part, which rotates the arm outward and did more of the work as the arm was raised^2,9.
• The trapezius, especially its lower part in eccentric-focused versions¹⁵.

Sources

1. Alizadehkhaiyat O, Hawkes DH, Kemp GJ, Frostick SP (2015). Electromyographic Analysis of the Shoulder Girdle Musculature During External Rotation Exercises.. Orthopaedic Journal of Sports Medicine. doi:10.1177/2325967115613988 PMID 26740950
2. Ryan G, Johnston H, Moreside J (2018). Infraspinatus Isolation During External Rotation Exercise at Varying Degrees of Abduction.. Journal of Sport Rehabilitation. doi:10.1123/jsr.2016-0217 PMID 28513278
3. Bitter NL, Clisby EF, Jones MA, Magarey ME, Jaberzadeh S, Sandow MJ (2007). Relative contributions of infraspinatus and deltoid during external rotation in healthy shoulders.. Journal of Shoulder and Elbow Surgery. doi:10.1016/j.jse.2006.11.007 PMID 17560805
4. Sugimoto D, Blanpied P (2006). Flexible foil exercise and shoulder internal and external rotation strength.. Journal of Athletic Training. PMID 17043696
5. Folkins E, Sahni S, Ryan J, Wooden S, Bushby G, Radzinski C (2021). Concentric and Eccentric Force Changes with Elastic Band and Isotonic Heavy Resistance Training: A Randomized Controlled Trial.. International Journal of Sports Physical Therapy. doi:10.26603/001c.23672 PMID 34123529
6. Clausen MB, Hölmich P, Rathleff M, Bandholm T, Christensen KB, Zebis MK, Thorborg K (2021). Effectiveness of Adding a Large Dose of Shoulder Strengthening to Current Nonoperative Care for Subacromial Impingement: A Pragmatic, Double-Blind Randomized Controlled Trial (SExSI Trial).. American Journal of Sports Medicine. doi:10.1177/03635465211016008 PMID 34048281
7. Ingwersen KG, Jensen SL, Sørensen L, Jørgensen HR, Christensen R, Søgaard K, Juul-Kristensen B (2017). Three Months of Progressive High-Load Versus Traditional Low-Load Strength Training Among Patients With Rotator Cuff Tendinopathy: Primary Results From the Double-Blind Randomized Controlled RoCTEx Trial.. Orthopaedic Journal of Sports Medicine. doi:10.1177/2325967117723292 PMID 28875153
8. Williams JM, Sinkler MA, Obremskey W (2023). Anatomy, Shoulder and Upper Limb, Infraspinatus Muscle.. StatPearls. PMID 30020627
9. Stokey PJ, Kaur S, Lee A, Behrens K, Ebraheim N (2024). Anatomy and Deficiency of the Deltoid Muscle: A Review of Literature.. Orthopedic Reviews. doi:10.52965/001c.115352 PMID 38562147
10. Escamilla RF, Yamashiro K, Paulos L, Andrews JR (2009). Shoulder muscle activity and function in common shoulder rehabilitation exercises.. Sports Medicine. doi:10.2165/00007256-200939080-00004 PMID 19769415
11. Kim TG, Ma R, Yu IY (2025). A study of effective exercise methods and resistance intensity for selective strengthening of the infraspinatus muscle.. Journal of Back and Musculoskeletal Rehabilitation. doi:10.1177/10538127241298546 PMID 39973266
12. Sakita K, Seeley MK, Myrer JW, Hopkins JT (2015). Shoulder-muscle electromyography during shoulder external-rotation exercises with and without slight abduction.. Journal of Sport Rehabilitation. doi:10.1123/jsr.2013-0116 PMID 25611493
13. Sung JH, Kim GT, Shin H, Lee D, Wang J (2026). The effects of shoulder abduction angle and elastic band resistance on shoulder muscle activity during external rotation exercises.. Scientific Reports. doi:10.1038/s41598-025-34767-w PMID 41559205
14. Reinold MM, Wilk KE, Fleisig GS, Zheng N, Barrentine SW, Chmielewski T, Cody RC, Jameson GG, Andrews JR (2004). Electromyographic analysis of the rotator cuff and deltoid musculature during common shoulder external rotation exercises.. Journal of Orthopaedic and Sports Physical Therapy. doi:10.2519/jospt.2004.34.7.385 PMID 15296366
15. Fukunaga T, Orishimo KF, McHugh MP (2022). Electromyographic analysis of select eccentric-focused rotator cuff exercises.. Physiotherapy Theory and Practice. doi:10.1080/09593985.2021.1949767 PMID 34313183
16. Whittaker RL, Alenabi T, Kim SY, Dickerson CR (2022). Regional Electromyography of the Infraspinatus and Supraspinatus Muscles During Standing Isometric External Rotation Exercises.. Sports Health. doi:10.1177/19417381211043849 PMID 34657490
17. Betts JG, Young KA, Wise JA, Johnson E, Poe B, Kruse DH, Korol O, Johnson JE, Womble M, DeSaix P (2022). Anatomy and Physiology 2e. OpenStax. Link
18. Akhtar A, Richards J, Monga P (2021). The biomechanics of the rotator cuff in health and disease - A narrative review.. Journal of Clinical Orthopaedics and Trauma. doi:10.1016/j.jcot.2021.04.019 PMID 34012769
19. Jeno SH, Munjal A, Schindler GS (2023). Anatomy, Shoulder and Upper Limb, Arm Supraspinatus Muscle.. StatPearls. PMID 30725887
20. Tsuruike M, Ellenbecker TS (2022). A comparison of teres minor and infraspinatus muscle activation in the prone position.. JSES International. doi:10.1016/j.jseint.2021.09.005 PMID 35141685
21. Reece AA, Parkinson JE, Cudlip AC, Page P, Holmes MWR (2021). Instructional Cueing Alters Upper Limb Muscle Activity and Kinematics During Elastic Resistance Exercise.. American Journal of Physical Medicine and Rehabilitation. doi:10.1097/PHM.0000000000001724 PMID 34793375
22. Yu IY, Oh SI, Jung WJ, Oh J (2019). Appropriate Resistance Intensity and Effective Exercise for Activation of Infraspinatus.. International Journal of Sports Medicine. doi:10.1055/a-0960-9676 PMID 31319428
23. Clisby EF, Bitter NL, Sandow MJ, Jones MA, Magarey ME, Jaberzadeh S (2008). Relative contributions of the infraspinatus and deltoid during external rotation in patients with symptomatic subacromial impingement.. Journal of Shoulder and Elbow Surgery. doi:10.1016/j.jse.2007.05.019 PMID 18162415
24. Lambers Heerspink FO, Veen EJD, Dorrestijn O, Visser CPJ, Leijs MJC, Van Poppel D, Stroomberg PA, Ottenheijm RPG, Kallewaard JW, De Ruiter TJW, Martens HA, Janssen FM, Geltink T, Ruiter MS, Van Raaij JJAM (2026). Update of guideline for diagnosis and treatment of subacromial pain syndrome: a multidisciplinary review by the Dutch Orthopedic Association Part 1: preventive measures, diagnostics, and non-surgical treatment of subacromial pain syndrome.. Acta Orthopaedica. doi:10.2340/17453674.2026.45365 PMID 41718640
25. Kinsella R, Pizzari T (2017). Electromyographic activity of the shoulder muscles during rehabilitation exercises in subjects with and without subacromial pain syndrome: a systematic review.. Shoulder and Elbow. doi:10.1177/1758573216660038 PMID 28405223
26. Treiber FA, Lott J, Duncan J, Slavens G, Davis H (1998). Effects of Theraband and lightweight dumbbell training on shoulder rotation torque and serve performance in college tennis players.. American Journal of Sports Medicine. doi:10.1177/03635465980260040601 PMID 9689369
27. Andersson SH, Bahr R, Clarsen B, Myklebust G (2017). Preventing overuse shoulder injuries among throwing athletes: a cluster-randomised controlled trial in 660 elite handball players.. British Journal of Sports Medicine. doi:10.1136/bjsports-2016-096226 PMID 27313171
28. Lazzarini SG, Bettariga F, Mosconi B, Maestroni L, Cordani C, Bandini E, Dal Farra F, Lopez P, Arienti C (2026). Comparative effectiveness of physical therapy interventions in adults with rotator cuff tendinopathy: a systematic review and network meta-analysis.. British Journal of Sports Medicine. doi:10.1136/bjsports-2025-110024 PMID 42135016
29. Malliaras P, Johnston R, Street G, Littlewood C, Bennell K, Haines T, Buchbinder R (2020). The Efficacy of Higher Versus Lower Dose Exercise in Rotator Cuff Tendinopathy: A Systematic Review of Randomized Controlled Trials.. Archives of Physical Medicine and Rehabilitation. doi:10.1016/j.apmr.2020.06.013 PMID 32682937
30. Zhang B, Raguzzi IA, Dupuis F, Gianola S, Morgan-Daniel J, Roy JS, Pozzi F (2026). Addressing Shoulder Weakness in Individuals With Rotator Cuff-Related Shoulder Pain: A Systematic Review With Meta-analysis.. Journal of Orthopaedic and Sports Physical Therapy. doi:10.2519/jospt.2025.13445 PMID 41620837
31. Currier BS, D'Souza AC, Singh MAF, Lowisz CV, Rawson ES, Schoenfeld BJ, Smith-Ryan AE, et al (2026). American College of Sports Medicine Position Stand. Resistance Training Prescription for Muscle Function, Hypertrophy, and Physical Performance in Healthy Adults: An Overview of Reviews.. Medicine and science in sports and exercise. doi:10.1249/MSS.0000000000003897 PMID 41843416
32. Picha KJ, Almaddah MR, Barker J, Ciochetty T, Black WS, Uhl TL (2019). Elastic Resistance Effectiveness on Increasing Strength of Shoulders and Hips.. Journal of Strength and Conditioning Research. doi:10.1519/JSC.0000000000002216 PMID 28922213
33. Matsumura A, Tateuchi H, Nakamura M, Ichihashi N (2023). Effect of 8-week Shoulder External Rotation Exercise with Low Intensity and Slow Movement on Infraspinatus.. Physical Therapy Research. doi:10.1298/ptr.E10227 PMID 37621568

Every source the library cites

Changes

• October 23, 2026 Added a Progressive overload section.
• September 29, 2026 Tidy pass: minor review findings fixed, glosses aligned with the reviewed glossary.
• September 29, 2026 First published.