The effects of standardised versus individualised seat height on 1-minute sit-to-stand test performance in healthy individuals: a randomised crossover trial

Abstract

Purpose: We aimed to (i) investigate differences in 1-minute sit-to-stand test (1MSTST) performance (i.e., the number of repetitions) between a standardised modality (i.e., starting from a conventional chair with 46 cm seat height) and an individualised modality (i.e., starting with a knee joint flexion angle of 90°), and to (ii) quantify the influence of tibia and femur length on 1MSTST performance.

Methods: Healthy participants were recruited for this randomised crossover study, performing each 1MSTST modality twice in a randomised order. The primary outcome was the number of repetitions in the 1MSTST. Secondary endpoints were the acute responses in peripheral oxygen saturation, heart rate, and leg fatigue and dyspnoea. Additionally, we investigated correlations of performance with knee extensor strength in both modalities.

Results: Thirty participants were recruited and completed the study. They achieved significantly less repetitions in the standardised 1MSTST compared to the individualised 1MSTST (B = - 12.1, 95% confidence interval [95% CI] = - 14.8/- 9.4, p < 0.001). We found a significant effect of femur length on 1MSTST performance (B = - 1.6, 95% CI = - 2.6/- 0.7, p = 0.01), tibia length showed significant interaction with the 1MSTST modality (B = 1.2, 95% CI = 0.2/2.2, p = 0.03).

Conclusion: An individualisation of the 1MSTST starting position to 90° knee flexion angle leads to more repetitions compared to the traditional starting position. The higher repetition count is explained by controlling for differences in tibia length. We recommend individualisation of the 1MSTST, enabling more valid comparisons across populations and study samples.

Trial registration number: http://www.

Clinicaltrials: gov , NCT04772417.

Trial registration date: February 26, 2021.

Keywords: 1-minute sit-to-stand test; Exercise capacity; Functional exercise testing; Morphology; Seat height.

Fig. 1

Experimental day. Participants attended a single experimental day and were randomly assigned to the sequence of tests (i.e., the order of Period 1 and Period 2). The standardised 1MSTST was done on a standard chair with seat height 46 cm; the individualised 1MSTST was done from a seat height adjusted to a knee flexion angle of 90° in the starting position. 1MSTST 1-minute sit-to-stand test

Fig. 2

Study participant flow diagram. Period describes which order of tests the participants were randomised to; S-I standardised (i.e., 46 cm seat height)–individualised (i.e., 90° knee flexion angle in starting position); I-S individualised–standardised; S standardised; I individualised

Fig. 3

Repetitions performed in the standardised and individualised 1MSTST. Individual data is stratified for females (red circles) and males (blue triangles). 1MSTST 1-minute sit-to-stand test

Fig. 4

Acute physiological responses in the standardised and the individualised 1MSTST. Displayed as individual changes (Δ). Individual data is stratified for females (red circles) and males (blue triangles). The panels show responses in a heart rate; b SpO₂; c perception of leg fatigue; d perception of dyspnoea. 1MSTST 1-minute sit-to-stand test; bpm, beats per minute; SpO₂ peripheral oxygen saturation

Fig. 5

Correlations between allometrically scaled 1MSTST repetitions and knee extension torque. Individual data is stratified for females (red circles) and males (blue triangles). a standardised 1MSTST and right knee extension torque; b standardised 1MSTST and left knee extension torque; c individualised 1MSTST and right knee extension torque; d individualised 1MSTST and left knee extension torque. 1MSTST 1-minute sit-to-stand test; BM body mass; Nm Newton metres