This observational study aims to learn about peripheral muscle strength in healthy adults and people with chronic respiratory diseases. The study aims to develop reference data for quadriceps muscle strength and handgrip in adults living in Southern Europe and to assess whether these reference data can be used in people with chronic respiratory diseases.
The main questions it aims to answer are:
* What are the normal values for quadriceps and handgrip muscle strength in healthy adults aged 18-89 years living in Spain, Portugal and Italy? * Can the reference values developed in healthy adults be applied to people with chronic respiratory diseases?
Participants will attend one study visit. During this visit, researchers will:
* Measure quadriceps muscle strength and handgrip. * Collect information about age, sex, height, weight and other health characteristics. * Perform simple functional tests related to mobility and physical performance. * Ask participants to complete questionnaires about symptoms, physical activity and health-related quality of life.
Age between 18-89 years.
Spanish, Portuguese or Italian, or permanently resident in one of those countries for at least five years.
Be community-dwelling (i.e., not hospitalised or institutionalised).
Be functionally independent and capable of performing study assessments without assistance or limiting pain.
Acute or chronic musculoskeletal conditions affecting strength: recent fractures, severe osteoarthrosis, ligament injury, acute tendinitis in hands/knee areas, among others.
Recent surgery (e.g., within the past six months) in upper or lower limbs.
Neuromuscular disorders: Parkinson, multiple sclerosis, stroke, peripheral neuropathies, among others.
Non-communicable diseases affecting strength or functional status: active cancer, any unstable heart diseases; any CRD; active rheumatological diseases, obesity (BMI≥30kg/m2), uncontrolled metabolic diseases, among others (not included: controlled dyslipidaemia or arterial hypertension).