Evidence map›Paper›PMID 33005427›Full record

ArticleBMC sports science, medicine & rehabilitation2020

Biomechanical conditioning of the motor unit transitory force decrease following a reduction in stimulation rate.

Joanna Rakoczy, Katarzyna Kryściak, Hanna Drzymała-Celichowska, Rositsa Raikova, Jan Celichowski

Open access · goldAbstract read
In one paragraph

Article in BMC sports science, medicine & rehabilitation, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
0.2field-weighted citation impact, top 53% 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

1 citing paper in PubMed, 2 citations in OpenAlex.

  1. Article
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 2 institutions in 2 countries.

Joanna RakoczyDepartment of Neurobiology, Poznan University of Physical Education, 27/39 Królowej Jadwigi Street, 61-871 Poznań, Poland.ORCID 0000-0003-1482-613X
Katarzyna KryściakDepartment of Neurobiology, Poznan University of Physical Education, 27/39 Królowej Jadwigi Street, 61-871 Poznań, Poland.
Hanna Drzymała-CelichowskaDepartment of Neurobiology, Poznan University of Physical Education, 27/39 Królowej Jadwigi Street, 61-871 Poznań, Poland.
Rositsa RaikovaInstitute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria.
Jan CelichowskiDepartment of Neurobiology, Poznan University of Physical Education, 27/39 Królowej Jadwigi Street, 61-871 Poznań, Poland.
Hungarian University of Sports Science · HUBulgarian Academy of Sciences · BG

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundThe biomechanical background of the transitory force decrease following a sudden reduction in the stimulation frequency under selected experimental conditions was studied on fast resistant motor units (MUs) of rat medial gastrocnemius in order to better understand the mechanisms of changes in force transmission.

methodsFirstly, MUs were stimulated with three-phase trains of stimuli (low-high-low frequency pattern) to identify patterns when the strongest force decrease (3-36.5%) following the middle high frequency stimulation was observed. Then, in the second part of experiments, the MUs which presented the largest force decrease in the last low-frequency phase were alternatively tested under one of five conditions to analyse the influence of biomechanical factors of the force decrease: (1) determine the influence of muscle stretch on amplitude of the force decrease, (2) determine the numbers of interpulse intervals necessary to evoke the studied phenomenon, (3) study the influence of coactivation of other MUs on the studied force decrease, (4) test the presence of the transitory force decrease at progressive changes in stimulation frequency, (5) and perform mathematical analysis of changes in twitch-shape responses to individual stimuli within a tetanus phase with the studied force decrease.

resultsResults indicated that (1) the force decrease was highest when the muscle passive stretch was optimal for the MU twitch (100 mN); (2) the middle high-frequency burst of stimuli composed of at least several pulses was able to evoke the force decrease; (3) the force decrease was eliminated by a coactivation of 10% or more MUs in the examined muscle; (4) the transitory force decrease occured also at the progressive decrease in stimulation frequency; and (5) a mathematical decomposition of contractions with the transitory force decrease into twitch-shape responses to individual stimuli revealed that the force decrease in question results from the decrease of twitch forces and a shortening in contraction time whereas further force restitution is related to the prolongation of relaxation.

conclusionsHigh sensitivity to biomechanical conditioning indicates that the transitory force decrease is dependent on disturbances in the force transmission predominantly by collagen surrounding active muscle fibres.

Indexed as

Force regulationMotor unitRate codingStimulation frequencyUnfused tetanus

Identifiers

PMID33005427
PMCPMC7523333
OpenAlexW3090713565

What OpenQuestion holds

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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.