Publications

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

In precision sports like archery, muscle control, fatigue reduction, and efficient movement execution are essential to an athlete’s performance. This study aimed to (i) analyze variations in muscle tone, stiffness, elasticity, creep, and relaxation at baseline, after archery shooting, and at a final post-session time point obtained after a standardized 30-min rest period followed by a manual-therapy session, and (ii) examine the relationship between acute fatigue after 100 shots and the magnitude of subsequent post-session change scores (not treatment effects).

Twenty experienced archery athletes (70% males) were recruited. Muscle properties (tone, stiffness, elasticity, creep, and relaxation time) were measured in the posterior deltoid, extensor digitorum, flexor carpi ulnaris, infraspinatus, lower trapezius, and upper trapezius at four time points: baseline, post-50 shots, post-100 shots, and post-manipulation.

Statistically significant within-session differences were found in the flexor carpi ulnaris, with reductions in tone (F = 3.631; p = 0.018; =0.160) and stiffness (F = 3.224; p = 0.029; =0.145) at the post-session (post-manipulation) assessment, which cannot be attributed to manual therapy in the absence of a sham/rest control group. No significant differences were found in other muscles, including the posterior deltoid, extensor digitorum, infraspinatus, lower trapezius, and upper trapezius. Large inverse correlations were found between baseline-to-post-100-shot changes and subsequent post-session change scores, particularly in the posterior deltoid (r=−0.588; p = 0.006), flexor carpi ulnaris (r=−0.573; p = 0.008), and trapezius muscles (r=−0.542 to r=−0.621). After Holm-Bonferroni correction across the 30 omnibus repeated-measures tests, no time effect remained statistically significant.

Given the largely non-significant repeated-measures ANOVA results, the correlation findings should be interpreted as exploratory and potentially influenced by inter-individual variability and regression-to-the-mean rather than as confirmation of a uniform therapeutic effect. Exploratory inverse correlations were observed between baseline-to-post-100-shot changes and subsequent post-session change scores, but because these change scores share a common time point and multiple correlations were examined, such associations should be interpreted with extreme caution and not as evidence of treatment response. Overall, the findings are best interpreted as descriptive time- and session-associated changes in passive myotonometric parameters, not as proof of manual-therapy-specific effects or improvements in performance or injury risk.

Keywords: manual therapy, sports recovery, muscle properties, archery, shooting

This study examined changes in myotonometry-derived mechanical parameters across baseline, post-shooting, and a final post-session assessment obtained after a standardized 30-min rest period followed by a manual-therapy session in experienced archers. Results were associated with differences in myotonometric parameters across time points in several muscles, but the single-group within-session design precludes causal attribution to manual therapy. Group-level analyses showed limited evidence of systematic mean changes across time for most muscles, therefore, findings are best framed as descriptive trajectories and exploratory associations rather than as confirmation of recovery effects attributable to manual therapy. Inverse delta–delta correlations suggest that participants who changed more from baseline to post-100 shots also tended to change more after the intervention, but this pattern does not establish that higher fatigue states reduce treatment responsiveness. After study-level Holm-Bonferroni correction of the 30 omnibus repeated-measures tests, no time effect remained statistically significant. Therefore, the findings are best framed as descriptive within-session trajectories rather than statistically confirmed intervention-related effects.

Because archery performance and injury outcomes were not measured and the design lacked a sham/control group, we do not claim improvements in accuracy, endurance, or injury prevention. Instead, the primary contribution is a standardized description of how myotonometric parameters may vary with shooting exposure and at a post-session time point following a rest interval and a manual-therapy session, under controlled measurement conditions. The study also emphasized the importance of muscles like the flexor carpi ulnaris and lower trapezius for stabilizing the wrist and shoulder, which are crucial for consistent shooting and injury prevention in archery. Because performance and injury endpoints were not measured and the design lacked randomization, blinding, and a sham/rest control, these data should not be used to infer effects on accuracy, fatigue recovery, or injury prevention. Future randomized sham-controlled studies are required to test whether manual therapy produces effects beyond time, rest, and contextual influences, and to estimate any manual-therapy-specific contribution.