Comparative ultrasonographic assessment of supraspinatus, infraspinatus, and biceps tendon thickness in bodybuilders and non-sportsperson.

Abstract

Background: Healthy tendons are crucial for sportspersons to prevent injuries. While resistances exercise is known to increase muscle size and composition, its impact on tendon thickness remains unclear. This study investigated potential differences in tendon thickness between bodybuilders and non-sportsperson control group and their association with training intensity/duration in bodybuilders.

Methods: Forty men in the age range 18 to 40 were included in the study. Fifteen bodybuilders (2-3 weekly upper body resistance training sessions, moderate-to-high intensity, > 6 months) and 25 non-sportsperson controls participated. All were free of tendon injuries in the studied muscles (biceps, supraspinatus, infraspinatus). Two independent physiatrists measured tendon thickness using ultrasound.

Results: No significant differences in tendon thickness were found between bodybuilders and non-sportsperson controls (dominant/non-dominant sides). However, within the bodybuilding group, tendon thickness showed strong positive correlations with both training intensity (r = 0.59-0.84) and exercise duration (r = 0.71-0.88).

Conclusion: This study found no overall group differences in tendon thickness between bodybuilders and non-sportsperson controls. However, for bodybuilders, increased training intensity and duration were associated with thicker tendons. Further research with larger samples and advanced techniques is warranted to understand the complex relationship between resistance training and tendon adaptations.