Dataset Information

Comparison of Muscle Coordination During Front Crawl and Backstroke With and Without Swimmer's Shoulder Pain.

ABSTRACT:

Background

Shoulder pain, known as swimmer's shoulder, is the most common injury for swimmers. Studies that have analyzed muscle activity have focused on the shoulder joint. However, the whole-body muscle coordination of swimmers with swimmer's shoulder is not clear, although swimming requires movements of the upper limbs, trunk, and lower limbs to obtain propulsive force. This study investigated differences in muscle coordination between swimmers with and without swimmer's shoulder during the front crawl and backstroke using muscle synergy analysis.

Hypothesis

Swimmers with swimmer's shoulder have muscle synergies differing from those without it.

Study design

Case-control study.

Level of evidence

Level 4.

Methods

A total of 20 elite swimmers who regularly swam front crawl and backstroke were included (swimmer's shoulder, n = 8; control, n = 12). Muscle synergy data were analyzed using the nonnegative matrix factorization method and compared between groups.

Results

For both front crawl and backstroke, there were 2 synergies in the control group and 3 synergies in the swimmer's shoulder group. During recovery, the control group showed coordinated triceps brachii, serratus anterior, upper trapezius, lower trapezius, internal oblique, and external oblique muscles activities; however, in the swimmer's shoulder group, the contribution of the upper limbs decreased and only that of the trunk muscles increased.

Conclusion

A comparison of muscle coordination during the front crawl and backstroke performed by swimmers with and without swimmer's shoulder revealed that coordination differed during the recovery phase. During both front crawl and backstroke, the swimmer's shoulder group could not maintain coordination with the upper limb when the trunk rolled, and split synergy was formed between the upper limbs and trunk.

Clinical relevance

Because coordination of the upper limbs and trunk is important during the recovery phase of front crawl and backstroke, swimmer's shoulder rehabilitation should introduce exercises to improve their coordination between the upper limbs and the trunk.

SUBMITTER: Matsuura Y

PROVIDER: S-EPMC10732115 | biostudies-literature | 2024 Jan-Feb

REPOSITORIES: biostudies-literature

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Publications

Comparison of Muscle Coordination During Front Crawl and Backstroke With and Without Swimmer's Shoulder Pain.

Matsuura Yuiko Y Matsunaga Naoto N Akuzawa Hiroshi H Oshikawa Tomoki T Kaneoka Koji K

Sports health 20230411 1

<h4>Background</h4>Shoulder pain, known as swimmer's shoulder, is the most common injury for swimmers. Studies that have analyzed muscle activity have focused on the shoulder joint. However, the whole-body muscle coordination of swimmers with swimmer's shoulder is not clear, although swimming requires movements of the upper limbs, trunk, and lower limbs to obtain propulsive force. This study investigated differences in muscle coordination between swimmers with and without swimmer's shoulder duri ...[more]

PMID: 37042038

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Dataset Information

Comparison of Muscle Coordination During Front Crawl and Backstroke With and Without Swimmer's Shoulder Pain.

Background

Hypothesis

Study design

Level of evidence

Methods

Results

Conclusion

Clinical relevance

Publications

Comparison of Muscle Coordination During Front Crawl and Backstroke With and Without Swimmer's Shoulder Pain.

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