Not too sure about this, but I think it just broadly means "abdominal pain/tenderness" which can be identified by performing a cough test.

For example:

Cough test
Bennett and colleagues35 consider signs of pain on coughing such as flinching, grimacing, or moving of hands to the abdomen as a positive test and reported a sensitivity of 78% with a specificity of 79% for the detection of peritonitis in a prospective study of 150 consecutive patients with abdominal pain.Sep 26, 2012
Evaluation and management of acute abdominal pain in the ... - NCBI

https://www.ncbi.nlm.nih.gov › pmc › articles › PMC3468117

Relacionado con el cough test, pelvic floor muscle assessment parece ser la expresión habitual equivalente en inglés. La evaluación de la competencia abdominal se refiere precisamente a la musculatura profunda del abdomen, si bien cabe revisar el original y confirmar si efectivamente se refiere al suelo pélvico o a la musculatura abdominal superficial, por ejemplo en evaluaciones postquirúrgicas, en cuyo caso no he encontrado equivalentes tan frecuentes en inglés (abdominal muscle assessment/function).

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a maximum PFM [pelvic-floor muscle] contraction does not seem to be possible without a co-contraction of the abdominal muscles, especially the transversus abdominis and internal oblique muscles. This abdominal contraction can be observed as a small inward movement of the lower abdomen.
https://academic.oup.com/ptj/article/85/3/269/2805029


That lower abdomen muscle contraction is what competencia abdominal usually stands for. It is not exactly a pelvic floor muscle assessment but a "lower abdomen deep muscle assessment", which is directly related to pelvic floor function. I still wonder how that is called in English but I hope this can be of help. Also, here you have an interesting and very "graphic" description of what "competencia abdominal" refers to:
https://www.enformaconbodypump.com/la-importancia-de-la-comp...

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May be abdominal (muscle) assessment might work after all -as reference to the evaluation of lower abdominal muscle function

All participants underwent a pelvic floor muscle (PFM) and abdominal muscle assessment
https://www.google.es/url?sa=t&source=web&rct=j&url=https://...



Literally, anyhow, competencia abdominal stands for abdominal (muscle) function.

https://books.google.co.uk › books
- Translate this page
Robert W. Wilmott, ‎Andrew Bush, ‎Robin R Deterding - 2019 - ‎Medical
... pueden causar aerofagia. A su vez, la distensión gástrica puede alterar la eficacia de la VNI debido a la competencia abdominal para la expansión pulmonar.


Muscles of Respiration - Physiopedia


https://www.physio-pedia.com › Muscles_of_Respiration

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Muscles that helpful in expanding the thoracic cavity are called the inspiratory ... they form a complex arrangement in the form of semirigid bellows around the lungs. ... The accessory expiratory muscles are the abdominal muscles: rectus, ...

https://www.ncbi.nlm.nih.gov › pmc › articles › PMC4868203

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by MH Rhee - ‎2016 - ‎Cited by 3 - ‎Related articles
28 Apr 2016 - Key words: Smoking, Cough, Abdominal muscle activation ... In order to perform a cough, strong contraction of the expiratory muscles is required). ... the MVIC for each muscle based on the manual muscle test) was measured ...

https://www.proz.com/kudoz/spanish-to-english/medical-cardio...


I don't think this has to do directly with the pelvic floor muscles

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Para una sesión, lo primero es hacer unas valoraciones previas por un técnico de hipopresivos para estudiar el estado de la competencia abdominal, la competencia perineal, la diastesis abdominal (separación rectos abdominales), tonicidad abdominal, tonicidad diafragmatica, medición perimetro abdominal e, incluso, se podrían tomar fotos para ir comparando.
https://lowpressurefitness.com/lpfjournal/en/too-much-back-p...

The relaxation of the abdominal muscles: abdominal diastasis and theenlargement of the abdomen increases the physiological lumbar curve of thepregnant woman. But also the deep abdominal muscles (obliques and transversus abdominis) lose their competence and tone.18 May 2017


www.balancemyworld.co.uk › engaging-the-deep-abdominals-how-and-why

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27 Jan 2016 - We always aim to work in Pilates with our core abdominal muscles ... Pelvic Floor (perineum) – this muscles supports the containment of all ...



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so

competencia abdominal = competent abdominal muscles/functional abdominal muscles


competencia perineal = competent pelvic floor muscles/functional pelvic floor muscles

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Test de competencia Perineal
Nos informa del estado del suelo pélvico.
Nos sentamos y nos concentramos en la musculatura del suelo pélvico. Incluso podemos sentarnos sobre nuestra mano para percibir que ocurre ahora en el periné cuando hacemos el esfuerzo de toser.

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https://www.enformaconbodypump.com › la-importanci...
Translate this page
6 Feb 2017 - Test de competencia Abdominal. Nos informa de la función que realiza la musculatura profunda del abdomen. N

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The abdominal drawing-in manoeuvre for detecting activity in ...

https://bmjopen.bmj.com › content
by K Kaping - ‎2015 - ‎Cited by 7 - ‎Related articles
To assess the activity of the deep abdominal muscles, a specific clinical test is available: the abdominal drawing-in manoeuvre (ADIM).13 Through manual ...

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https://www.topendsports.com › testing › abdominal-testing
There are numerous fitness tests for measuring the function of the abdominal muscles (or 'abs' as they are generally called in the fitness industry). This is a very ..