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30 Seconds Sit-to-Stand Test: Reference Values for the Chilean Population.

Marisol Barros-Poblete1, Rodrigo Torres-Castro2, Matías Otto-Yáñez3

  • 1Universidad Austral de Chile, Valdivia, Chile.

Revista Medica De Chile
|June 17, 2025
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This study established reference values for the 30-seconds sit-to-stand test (30s-STST) in Chilean adults aged 18-80. These findings provide crucial benchmarks for assessing functional capacity and guiding rehabilitation strategies in the region.

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Area of Science:

  • Gerontology
  • Rehabilitation Medicine
  • Biometrics

Background:

  • Functional capacity assessment is vital for identifying mobility limitations and personalizing rehabilitation.
  • The 30-seconds sit-to-stand test (30s-STST) is a validated and reliable measure of lower limb muscle function.

Purpose of the Study:

  • To establish normative reference values for the 30s-STST in adults aged 18-80 within the Chilean population.
  • To provide age- and sex-specific percentiles for the 30s-STST.

Main Methods:

  • A cross-sectional study involving 499 adults across six Chilean centers (universities and family health centers).
  • Data collected included anthropometrics, physical activity levels, smoking status, and 30s-STST repetitions.
  • Sex- and age-specific normative percentiles were calculated for six age groups, with regression analyses to identify predictors of performance.

Main Results:

  • Median 30s-STST repetitions varied by age and sex, with generally higher scores in younger adults and men.
  • Specific median scores (25th-75th percentile) were reported for different age brackets for both women and men.
  • Predictive equations were derived: Men: 30s-STST = 25.364 - (age * 0.158); Women: 30s-STST = 39.264 - (age * 0.136) - (height * 0.095).

Conclusions:

  • Reference values for the 30s-STST were successfully established for the adult Chilean population.
  • These values can serve as a benchmark for clinical assessment and research in similar Southern Cone populations.
  • The study highlights the utility of the 30s-STST in evaluating functional capacity across diverse adult age groups.