Evidence map›Paper›PMID 42412375›Full record

ArticleKnee surgery, sports traumatology, arthroscopy : official journal of the ESSKA2026

High prevalence of muscle stability deficits in semi-professional football players-Adaptive Force assessment reveals selective impairment of holding capacity with preserved maximal strength: A cross-sectional study.

Laura V Schaefer, Frank N Bittmann, Jaali Ulrich, Robert Prill, Roland Becker

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Article in Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

5 authors.

Laura V SchaeferCentre of Orthopaedics, Traumatology and Plastic Surgery, University Hospital Brandenburg, Brandenburg Medical School Theodor Fontane, Brandenburg an der Havel, Germany.ORCID https://orcid.org/0000-0002-6289-6987
Frank N BittmannRegulative Physiology and Prevention, Department of Sports and Health Sciences, University of Potsdam, Potsdam, Germany.ORCID https://orcid.org/0000-0003-4514-8060
Jaali UlrichCentre of Orthopaedics, Traumatology and Plastic Surgery, University Hospital Brandenburg, Brandenburg Medical School Theodor Fontane, Brandenburg an der Havel, Germany.ORCID https://orcid.org/0009-0001-0467-9693
Robert PrillCentre of Orthopaedics, Traumatology and Plastic Surgery, University Hospital Brandenburg, Brandenburg Medical School Theodor Fontane, Brandenburg an der Havel, Germany.ORCID https://orcid.org/0000-0002-4916-1206
Roland BeckerCentre of Orthopaedics, Traumatology and Plastic Surgery, University Hospital Brandenburg, Brandenburg Medical School Theodor Fontane, Brandenburg an der Havel, Germany.ORCID https://orcid.org/0000-0003-1833-7608

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeDespite considerable research, strength screening has shown limited value for injury prediction. The concept of muscle stability assessed by Adaptive Force (AF) offers a distinct perspective-addressing neuromuscular holding capacity closer to injury-prone motions rather than pushing strength. This study aimed to assess the prevalence and distribution of muscle stability deficits in football players and their discriminative capacity relative to conventional strength parameters.

methodsAF and maximal voluntary isometric contraction (MVIC) were measured in 23 male semi-professional football players. Five muscle groups were tested bilaterally (knee extensors/flexors; hip flexors/adductors/abductors). AF was assessed by objectified manual muscle tests with a handheld device recording force and angular velocity. AF parameters, MVIC and the conventional hamstrings-to-quadriceps (H:Q) ratio were compared between stability categories.

resultsStability deficits were highly prevalent: 83% of players had at least one deficit; 31% of all tested muscle groups were unstable, highest in hip abductors (52%) followed by hamstrings (46%). The maximal holding capacity was selectively impaired in unstable muscles (on average 61% lower than the maximal force output), while MVIC and maximal AF did not differ between stability categories. The ratio of holding capacity to maximal AF (AF-Ratio) was the strongest discriminator (stable vs. unstable: d = 6.62, ω

conclusionMuscle instability represents a selective impairment of holding capacity with preserved maximal strength, not detected by MVIC testing. By capturing a distinct neuromuscular function, AF offers a novel mechanistic framework beyond pushing strength. Further studies in larger samples and prospective designs are required to assess the potential utility of stability assessment in clinical practice. LEVEL OF EVIDENCE: Level III, diagnostic studies.

Indexed as

Muscle, SkeletalMuscle StrengthSoccerAdultCross-Sectional StudiesHamstring MusclesHumansIsometric ContractionMalePrevalenceYoung AdultAdaptive forceFootball injuriesmuscle function assessmentmuscle stabilityneuromuscular control

Identifiers

PMID42412375
PMCPMC13418286

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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.