Publications

Background: Lateral Epicondylopathy (LE) is a common musculoskeletal condition characterized by pain over the lateral elbow.

Purpose: To examine the effects of eccentric stretching on pain, grip strength, and function in LE.

Methods: Forty participants with LE were randomized into study and control groups. The control group received cold application, deep friction massage, and a home exercise program (three times/week for four weeks). The study group additionally performed eccentric stretching (3 sets/15 repetitions, three times/week for four weeks). Outcomes included pain, grip strength, Patient-Rated Tennis Elbow Evaluation (PRTEE), viscoelastic muscle properties, Quick Disabilities of the Arm, Shoulder, and Hand (Quick DASH), and quality of life. Clinical relevance was assessed using the smallest worthwhile change (SWC).

Results: Significant Group×Time interactions were observed for grip strength (p < .001, ηp2 = 0.426), lateral pinch strength (p = .014, ηp2 = 0.150), and fingertip pinch strength (p = .014, ηp2 = 0.149), indicating greater improvements in the study group. PRTEE-function (p < .001, ηp2 = 0.443) and QuickDASH (p < .001, ηp2 = 0.598) also demonstrated significant interaction effects favoring the intervention. Significant interactions were further observed for muscle tone, stiffness, and elasticity at rest (ηp2 = 0.284–0.468) and for tone and stiffness during activity (ηp2 = 0.151–0.257; all p ≤ .013), indicating superior viscoelastic adaptations in the intervention group. No significant interaction was found for elasticity during activity (p = .322, ηp2 = 0.026). Pain outcomes showed no between-group differences (all p ≥ .512), although both groups demonstrated clinically meaningful reductions.

Conclusion: This study demonstrates for the first time that supervised eccentric stretching provides clinically meaningful improvements in strength, function, muscle viscoelastic properties, quality of life beyond conventional physiotherapy alone in chronic LE. These findings suggest that targeting passive tissue mechanics through controlled eccentric elongation may enhance functional recovery even when pain reduction is similar. Eccentric stretching may therefore represent a valuable adjunct strategy when functional restoration rather than pain relief alone is the primary therapeutic goal.

Keywords: lateral epicondylopathy, eccentric stretching, grip strength, functional level, muscle viscoelastic properties

The addition of supervised eccentric stretching to conventional physiotherapy resulted in statistically significant and clinically meaningful improvements in grip strength, pinch strength, upper-extremity function (PRTEE-function and QuickDASH), forearm muscle viscoelastic properties, and health-related quality of life in patients with chronic lateral epicondylopathy. These benefits exceeded the smallest worthwhile change thresholds and were significantly greater than those achieved with conventional therapy alone. In contrast, both interventions produced comparable and clinically important reductions in pain intensity (VAS and PRTEE-pain subscale), with no evidence of superiority for eccentric stretching in analgesic effect at 4 weeks. Therefore, while eccentric stretching appears highly promising as an adjunct for restoring strength and function, its specific impact on pain reduction remains inconclusive and warrants investigation in larger, longer-term trials. Overall, eccentric stretching is a safe, low-cost, and effective complement to standard care in lateral epicondylopathy, particularly when the primary therapeutic goals are functional restoration and improved quality of life rather than isolated pain relief.

Finally, it should be acknowledged that the intervention applied in this study includes features of assisted eccentric loading due to the use of EMS-induced muscle contraction during lengthening. Nevertheless, the primary therapeutic emphasis was on controlled elongation and modulation of passive tissue properties rather than high-load strength adaptation. This conceptual positioning may explain the observed changes in viscoelastic parameters and functional outcomes.