Publications

Myoton Clarification Note: A Guide to Interpreting the Inverse Relationship Between Logarithmic Decrement and Tissue Elasticity

Background: Low back pain (LBP) is highly prevalent among adolescent rowers and may be influenced by altered trunk-pelvic mechanics and hamstring characteristics. Hamstring-targeted physiotherapy interventions are widely used in clinical practice; however, comparative evidence regarding their effects on muscle mechanical properties and LBP in adolescent rowing populations is limited.

Objective: To compare the effects of ballistic hamstring stretching, hamstring extender exercise, and kinesiotaping on hamstring viscoelastic properties, low back pain, and athletic performance in elite adolescent rowers.

Methods: This single-blind, parallel-group randomized controlled trial included 60 elite male adolescent rowers (aged 14–18 years) with chronic low back pain, and participants were randomly assigned to three groups for a twelve-week program performed during training sessions four times per week. All outcomes were assessed at baseline and week 12, including hamstring viscoelastic properties measured using a handheld myotonometer, pain intensity assessed with the Numeric Pain Rating Scale, and athletic performance evaluated by the 2000-m rowing ergometer and standing long jump tests. Data were analyzed using age-adjusted analysis of covariance (ANCOVA).

Results: After adjustment for baseline values and age, both exercise-based interventions were associated with more favorable changes in hamstring viscoelastic properties and greater reductions in pain intensity compared with kinesiotaping (p < 0.001). Between-group differences in athletic performance were statistically significant but modest.

Conclusion: Hamstring-focused exercise interventions were associated with greater improvements in muscle mechanical properties and reductions in LBP compared with kinesiotaping in adolescent rowers. These findings support the inclusion of active hamstring exercises in rehabilitation programs for athletes with LBP.

Keywords: low back pain, adolescent rowers, viscoelastic properties, myotonometry, exercise, kinesiotaping, randomized controlled trial

This randomized controlled trial suggests that eccentric (HEE) and ballistic (HBS) hamstring exercises are associated with more favorable improvements in hamstring muscle mechanical properties and greater reductions in low back pain compared with kinesiotaping in elite adolescent rowers. All interventions were safe and well tolerated over the twelve-week intervention period.

Although small improvements in rowing-related performance were observed across groups, these changes were modest and did not consistently favor a single intervention, highlighting the complex and multifactorial nature of athletic performance. Overall, the findings indicate that hamstring-focused exercise-based interventions may represent a valuable component of physiotherapy and conditioning programs for adolescent rowers with low back pain.

Future research should include athletes from different age groups and sporting disciplines to improve generalizability. In addition, the incorporation of objective training load monitoring, longer follow-up periods, and biomechanical and neuromuscular assessments would help clarify the dose–response relationships and underlying mechanisms associated with hamstring-targeted interventions.