Research Article

Shoulder muscle weakness effects on muscle hardness around the shoulder joint and scapulae

Kubota Atsushi*, Takayanagi Chiho and Kishimoto Kohei

Published: 21 April, 2020 | Volume 5 - Issue 1 | Pages: 001-007

Purpose: The time course of muscle stiffness of muscles around the shoulder joint and the scapula was investigated according to the degree of muscle weakness. This study was conducted to clarify the recovery process of muscle hardness of the muscles surrounding the shoulder joint and the scapula after the shoulder internal and external rotational exercises.

Methods: Participants were 7 healthy men (23.6 ± 1.4 yr), repeated internal and external rotations of the shoulder joint until the mean work of three internal and external rotations each was less than 90%, 80%, or 70% of the standard. Muscle hardness of the supraspinatus muscle, the infraspinatus muscle, and the rhomboideus muscle was measured before, immediately after, and 1to 72 hr after each bout of exercise.

Muscle hardness was measured as Strain ratio using an ultrasound real-time tissue elastography. In addition, the rates of change were calculated using muscle hardness before exercise as the standard, to compare differences in the rate of change after exercise between conditions.

Results: The rates of change of the Strain ratio between measurements taken before and after exercise were compared among conditions for the infraspinatus muscle. Results were -7.1 ± 5.3, -15.2 ± 10.3, and -25.0 ± 8.8, respectively, at 90%, 80%, and 70%, with a significant difference between a decrease to 90% and to 70% (p < 0.05). Significant difference was found in the change over time for the infraspinatus muscle only between values obtained immediately after exercise and after 72 hr at a decrease to 70% (p < 0.05).

Conclusion: Those results described above demonstrated that the infraspinatus muscle and the supraspinatus muscle were harder immediately after exercise when the shoulder joint was at a higher degree of muscle weakness, and demonstrated that the change was likely to be recovered after 72 hr.

Read Full Article HTML DOI: 10.29328/journal.jsmt.1001049 Cite this Article Read Full Article PDF


Baseball shoulder; Elastography; Internal and external rotation; Conditioning


  1. Baltaci G, Johnson R, Kohi H 3rd. Shoulder range of motion characteristics in collegiate baseball players. J Sports Med Phys Fitness. 2001; 41: 236-242. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/11447368
  2. Oliver GD, Weimar WH. Hip and Shoulder Range of Motion in Youth Baseball Pitchers. J Strength Cond Res. 2016; 30: 2823-2827. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/25486297
  3. Crockett HC, Gross LB, Wilk KE, Schwartz ML, Reed J, et al. Osseous adaptation and range of motion at the glenohumeral joint in professional baseball pitchers. Am J Sports Med. 2002; 30: 20-26. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/11798991
  4. Amin NH, Ryan J, Fening SD, Soloff L, Schickendantz MS, et al. The Relationship Between Glenohumeral Internal Rotation Deficits, Total Range of Motion, and Shoulder Strength in Professional Baseball Pitchers. J Am Acad Orthop Surg. 2015; 23: 789-796. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/26609146
  5. Laudner KG, Wilson JT, Meister K. Elbow isokinetic strength characteristics among collegiate baseball players. Phys Ther Sport. 2012; 13: 97-100. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/22498150
  6. Myers JB, Laudner KG, Pasquale MR, Bradley JP, Lephart SM. Glenohumeral range of motion deficits and posterior shoulder tightness in throwers with pathologic internal impingement. Am J Sports Med. 2006; 34: 385-391. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/16303877
  7. Chou PP, Chou YL, Wang YS, Wang RT, Lin HT. Effects of glenohumeral internal rotation deficit on baseball pitching among pitchers og different ages. J Shoulder Elbow Surg. 2018; 27: 599-605. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/29241660
  8. Tyler TF, Mullaney MJ, Mirabella MR, Nicholas SJ, McHugh MP. Risk Factors for Shoulder and Elbow Injuries in High School Baseball Pitchers: The Role of Preseason Strength and Range of Motion. Am J Sports Med. 2014; 42: 1993-1999. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/24893778
  9. Bailey LB, Shanley E, Hawkins R, Beattie PF, Fritz S, et al. Mechanisms of Shoulder Range of Motion Deficits in Asymptomatic Baseball Players. Am J Sports Med. 2015; 43: 2783-2793. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/26403207
  10. Takenaga T, Sugimoto K, Goto H, Nozaki M, Fukuyoshi M, et al. Posterior Shoulder Capsules Are Thicker and Stiffer in the Throwing Shoulders of Healthy College Baseball Players: A Quantitative Assessment Using Shear-Wave Ultrasound Elastography. Am J Sports Med. 2015; 43: 2935-2942. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/26473012
  11. Byram IR, Bushnell BD, Dugger K, Charron K, Harrell FE Jr, et al. Preseason shoulder strength measurements in professional baseball pitchers: identifying players at risk for injury. Am J Sports Med. 2010; 38: 1375-1382. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/20489215
  12. Trakis JE, McHugh MP, Caracciolo PA, Busciacco L, Mullaney M, et al. Muscle strength and range of motion in adolescent pitchers with throwing-related pain: implications for injury prevention. Am J Sports Med. 2008; 36: 2173-2178. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/18596197
  13. Clarsen B, Bahr R, Andersson SH, Munk R, Myklebust G. Reduced glenohumeral rotation, external rotation weakness and scapular dyskinesis are risk factors for shoulder injuries among elite male handball players: a prospective cohort study. Br J Sports Med. 2014; 48: 1327-1333. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/24948083
  14. Moreno-Pérez V, Elvira J, Fernandez-Fernandez J, Vera-Garcia FJ. A comparative study of passive shoulder rotation range of motion, isometric rotation strength and serve speed between elite tennis players with and without history of shoulder pain. Int J Sports Phys Ther. 2018; 13: 39-49. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/29484240
  15. Kusano K, Nishishita S, Nakamura M, Tanaka H, Umehara J, et al. Acute effect and time course of extension and internal rotation stretching of the shoulder on infraspinatus muscle hardness. J Shoulder Elbow Surg. 2017; 26: 1782-1788. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/28684232
  16. Nordez A, Guével A, Casari P, Catheline S, Cornu C. Assessment of muscle hardness changes induced by a submaximal fatiguing isometric contraction. J Electromyogr Kinesiol. 2009; 19: 484-491. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/18158253
  17. Yanagisawa O, Niitsu M, Kurihara T, Fukubayashi T. Evaluation of human muscle hardness after dynamic exercise with ultrasound real-time tissue elastography: a feasibility study. Clin Radiol. 2011; 66: 815-819. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/21529793
  18. Kishimoto K, Sakuraba K, Kubota A, Fujita S. The effect of concentric and eccentric exercise on muscle hardness. Juntendo Medical Journal. 2018; 64: 371-378.
  19. Murayama M, Nosaka K, Yoneda T, Minamitani K. Changes in hardness of the human elbow flexor muscles after eccentric exercise. Eur J Appl Physiol. 2000; 82: 361-367. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/10985588
  20. Howell JN, Chleboun G, Conatser R. Muscle stiffness, strength loss, swelling and soreness following exercise-induced injury in humans. J Physiol. 1993; 464: 183-196. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/8229798
  21. Green MA, Sinkus R, Gandevia SC, Herbert RD, Bilston LE. Measuring changes in muscle stiffness after eccentric exercise using elastography. NMR Biomed. 2012; 25: 852-858. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/22246866
  22. Lacourpaille L, Nordez A, Hug F, Couturier A, Dibie C, et al. Time-course effect of exercise-induced muscle damage on localized muscle mechanical properties assessed using elastography. Acta Physiol (Oxf). 2014; 211: 135-146. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/24602146
  23. Proske U, Allen TJ. Damage to skeletal muscle from eccentric exercise. Exerc Sport Sci Rev. 2005; 33: 98-104. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/15821431
  24. Peake J, Nosaka K, Suzuki K. Characterization of inflammatory responses to eccentric exercise in humans. Exerc Immunol Rev. 2005; 11: 64-85. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/16385845
  25. Peake JM, Neubauer O, Della Gatta PA, Nosaka K. Muscle damage and inflammation during recovery from exercise. J Appl Physiol. 2017; 122: 559-570. PubMed: https://www.ncbi.nlm.nih.gov/pubmed/28035017


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