Neuromuscular activation in swimming and water polo

K. De Jesus, P. Figueiredo, P. Gonçalves, R. J. Fernandes, J. P. Vilas-Boas

Research output: Chapter in Book/Report/Conference proceedingChapter

1 Citation (Scopus)


Surface electromyography (sEMG) represents the electrical activity generated in the muscle fibres in response to the activation provided by the innervation of motor neurons. sEMG evaluations have been implemented in aquatic sports specially to describe muscles activity in swimming and water polo. This Chapter affords an overview on two decades of sEMG research in swimming and water polo conducted by the Faculty of Sport and Porto Biomechanics Laboratory, both from the University of Porto (Porto, Portugal). A brief survey on the sEMG fundamentals will be initially presented, followed by a frequency analysis of the studied topics, muscles, populations, types of equipment and data collection, data treatment and variables, main results, relevance to practice and further research interests. Considering our group sEMG evaluations background (with 28 studies, comprising two literature reviews), it is possible to say that most of the researches have focused on swimming (80.77%), with the front crawl swimming technique and the upper limb muscular activation being greatly emphasized (52.38%; e.g., Biceps Brachii). In water polo, shooting technique variations have emerged as the most studied skill (60%), with a special focus on the upper limb (66.6%; e.g., Triceps Brachii) and trunk (66.6%; e.g., Latissimus Dorsi) muscle activity. Lower limb muscles have been mainly studied during swimming turns and water polo eggbeater kick variations (e.g., Gastrocnemius Medialis). Swimmers’ population and water polo players have been commonly ranked by competitive level (61.54%). Cabled sEMG online system has been often used in both aquatic sports (96.15%), with a wireless approach already tested in front crawl swimming (3.85%). Electrode insulation techniques have been similar for cabled and wireless systems with a plastic film edge covered by an adhesive tape. Cable settings have been defined according to data collection purpose to minimize mechanical artefacts and improve swimmers and players’ comfort during experimental settings. Qualitative and quantitative sEMG analysis has been performed with AcqKnowledge and MatLab routines, respectively. To obtain quantitative information, amplitude term basic signal processing has been used for sports in general, including sEMG signal rectification, linear envelope, integration and normalisation through maximal isometric voluntary contraction (57.69%), dynamic peak (23.07%) and maximal integrated value (15.38%). Frequency analysis has been conducted with spectral indices (11.54%) to explain local muscular fatigue during front crawl swimming and water polo shooting. Fatigue has been noticed mainly on upper limb muscles during a 200 m maximal front crawl swimming, but not in 10 water polo shooting repetitions. Differences in muscular activation amplitude seen when comparing technical variations of water polo shooting, eggbeater kick, backstroke to breaststroke turn have not been evidenced in flip turn and backstroke start technique. With the implementation of the current back-plate for the rear foot support during ventral starts, lower limb muscles have displayed main activation from the hands-off to take-off instants. Despite researchers and coaches can benefit from accumulated sEMG knowledge for training assistance, further studies are required to include mainly other swimming events and water polo skills, adding also synchronised swimming, triggering an analysis through proficiency levels and task constraints.

Original languageEnglish
Title of host publicationSurface Electromyography
Subtitle of host publicationFundamentals, Computational Techniques and Clinical Applications
PublisherNova Science Publisher Inc.
Number of pages34
ISBN (Electronic)9781536102222
ISBN (Print)9781536102024
Publication statusPublished - Jan 1 2016
Externally publishedYes


  • Biomechanics
  • Individual and team aquatic sports
  • Kinesiological EMG
  • sEMG

ASJC Scopus subject areas

  • General Medicine
  • General Biochemistry,Genetics and Molecular Biology


Dive into the research topics of 'Neuromuscular activation in swimming and water polo'. Together they form a unique fingerprint.

Cite this