Evidence map›Paper›PMID 29668731›Full record

ArticlePloS one2018

A wavelet based time frequency analysis of electromyograms to group steps of runners into clusters that contain similar muscle activation patterns.

Vinzenz von Tscharner, Martin Ullrich, Maurice Mohr, Daniel Comaduran Marquez, Benno M Nigg

Open access · goldAbstract read
In one paragraph

Article in PloS one, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers.

0numbers the graph read from it
0cells of the map it votes in
12citing papers in PubMed
2.8field-weighted citation impact, top 10% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

12 citing papers in PubMed, 32 citations in OpenAlex.

  1. Article
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  3. The effect of prolonged walking on leg muscle activity patterns and vulnerability to perturbations.Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology · 2023
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors at 1 institution in 1 country.

Vinzenz von TscharnerFaculty of Kinesiology, Human Performance Laboratory, University of Calgary, Calgary, Alberta, Canada.ORCID 0000-0002-5779-6244
Martin UllrichFaculty of Kinesiology, Human Performance Laboratory, University of Calgary, Calgary, Alberta, Canada.
Maurice MohrFaculty of Kinesiology, Human Performance Laboratory, University of Calgary, Calgary, Alberta, Canada.
Daniel Comaduran MarquezFaculty of Kinesiology, Human Performance Laboratory, University of Calgary, Calgary, Alberta, Canada.
Benno M NiggFaculty of Kinesiology, Human Performance Laboratory, University of Calgary, Calgary, Alberta, Canada.
University of Calgary · CA

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeTo wavelet transform the electromyograms of the vastii muscles and generate wavelet intensity patterns (WIP) of runners. Test the hypotheses: 1) The WIP of the vastus medialis (VM) and vastus lateralis (VL) of one step are more similar than the WIPs of these two muscles, offset by one step. 2) The WIPs within one muscle differ by having maximal intensities in specific frequency bands and these intensities are not always occurring at the same time after heel strike. 3) The WIPs that were recorded form one muscle for all steps while running can be grouped into clusters with similar WIPs. It is expected that clusters might have distinctly different, cluster specific mean WIPs.

methodsThe EMG of the vastii muscles from at least 1000 steps from twelve runners were recorded using a bipolar current amplifier and yielded WIPs. Based on the weights obtained after a principal component analysis the dissimilarities (1-correlation) between the WIPs were computed. The dissimilarities were submitted to a hierarchical cluster analysis to search for groups of steps with similar WIPs. The clusters formed by random surrogate WIPs were used to determine whether the groups were likely to be created in a non-random manner.

resultsThe steps were grouped in clusters showing similar WIPs. The grouping was based on the frequency bands and their timing showing that they represented defining parts of the WIPs. The correlations between the WIPs of the vastii muscles that were recorded during the same step were higher than the correlations of WPIs that were recorded during consecutive steps, indicating the non-randomness of the WIPs.

conclusionsThe spectral power of EMGs while running varies during the stance phase in time and frequency, therefore a time averaged power spectrum cannot reflect the timing of events that occur while running. It seems likely that there might be a set of predefined patterns that are used upon demand to stabilize the movement.

Indexed as

AthletesElectromyographyRunningAdultCluster AnalysisHumansMaleMuscle ContractionMuscle, SkeletalYoung Adult

Identifiers

PMID29668731
PMCPMC5906018
OpenAlexW2800028669

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.