The immediate effect of myofascial trigger point dry needling of four shoulder girdle muscles on the 100m lap- times of asymptomatic competitive swimmers in Bloemfontein

Abstract

Background Competitive swimming, as with most other sports that are participated in at more than a recreational level, involves a substantial amount of training. Training excessively results in the overuse of muscles. The overuse of muscles commonly causes the production of myofascial trigger points (MFTPs) within the overworked muscles. The presence of MFTPs is a condition known as myofascial pain syndrome (MPS).

Myofascial trigger points may be active or latent. Either way, they produce a wide range of effects. This study focuses on the effect of reduced muscle strength. Muscle strength is essential to athletes as it determines performance. Swimmers with MFTPs will not perform at their full ability.

Dry needling is an effective form of treatment for MFTPs as it produces immediate relief from the effects of MFTPs. There is not enough information on the immediate effects of dry needling on athlete performance. Since dry needling brings about the immediate relief of MFTPs, this study aims to restore a swimmer’s muscle power and hence improvement of their swimming performance post-intervention.

Aim The aim of this study was to determine the immediate effect of dry needling common myofascial trigger points (MFTP) found in four muscles of the shoulder girdle on competitive swimmers’ 100m freestyle lap-times.

Methods The design was a pre-test post-test quasi-experimental study. Thirty five competitive swimmers between the ages of 16 and 30 years old participated in this study. Each participant underwent one assessment. Participants’ lap-times were taken using a Sportline Econosport Stopwatch. The pre- and post-intervention lap-times were compared to each other using statistical analysis. The intervention for the purpose of the study was trigger point dry needling. Myofascial trigger points were assessed using manual palpation and the Myofascial Diagnostic Scale (MDS).

Results The median lap time was slightly longer post intervention (0:01:16.10) than pre-intervention (0:01:16.03), and was highly statistically significant (p=0.001). The results of the study were inconclusive, however, as there were too many confounding variables (for example, fatigue due to repeatedly swimming laps, swimmers of a lower caliber and hence quicker fatigue rate being included in the study)which negated the effect of dry needling and so the poorer performance of the participants post-intervention could not be attributed entirely to the intervention. A small number of participant’s lap-times decreased post-intervention i.e. they performed better post-intervention. These individualswere predominantly sprint-swimmers.

Conclusion Dry needling negatively affects immediate lap-time performance. Future studies should reduce the number of variables affecting the study, for example, having a sprinter versus long-distance swimmer group, testing the outcome of dry needling after the swimmer has had sufficient time (for example, a day) to rest post-intervention.