O’Connor FK; School of Health Sciences and Social Work, Griffith University, Southport, Qld, Australia.
Chen D; Sharma P; Adsett J; Hwang R; Roberts L; Bach A; Louis M; Morris N;
Heart, lung & circulation [Heart Lung Circ] 2025 Aug; Vol. 34 (8), pp. 789-797.
Date of Electronic Publication: 2025 Jun 20.
Background: Short-duration sit-to-stand tests are utilised in rehabilitation settings to alleviate logistical challenges associated with the six-minute walk test (6MWT). We assessed the utility of the 30-second sit-to-stand (30-STST) and 60-second sit-to-stand (60-STST) tests as surrogate measures of the 6MWT.
Method: On separate days, 16 male participants (71 [7] years) with stable heart failure with reduced ejection fraction (36.9 [4.9] %) completed two 6MWT and the 30-STST and 60-STST. Pulmonary gas exchange (oxygen consumption, carbon dioxide production [V˙CO 2 ], ventilation [V˙ E ], respiratory exchange ratio, ventilatory equivalent for CO 2 [V˙ E /V˙CO 2 ] and partial pressure of end-tidal CO 2 [P ET CO 2 ]) was measured using a portable metabolic system. Non-invasive haemodynamics (cardiac output, stroke volume, arteriovenous oxygen difference) were measured using impedance cardiography. Mean arterial pressure, heart rate, oxygen saturation and dyspnoea (0-10 scale, arbitrary units) were also monitored. Mixed-effects models (Bonferroni corrected) accounting for time (pre-exercise rest, end-exercise) and test (6MWT, 30-STST, and 60-STST) were used to assess the relation between results observed during each testing modality.
Results: While P ET CO 2 (mean difference [95% confidence interval], -4.9 [-8.9 to -0.8] mmHg), and dyspnoea (1 [0-2] arbitrary units) differed between the 6MWT and 60-STST, no other differences were observed between these tests. In contrast, oxygen consumption (-0.5 [-0.6 to -0.3] L.min -1 ), V˙CO 2 (-0.5 [-0.7 to -0.4] L.min -1 ), V˙ E (-18.3 [-26.0 to -10.0] L.min -1 ), P ET CO 2 (-5.1 [-9.6 to -0.7] mmHg), cardiac output (-2.4 [-4.9 to -0.3] L.min -1 ), heart rate (-20 [-33 to -7] beats/min) differed between the 6MWT and the 30-STST, however, no other differences were observed between the 6MWT and the 30-STST.
Conclusions: Cardiopulmonary, non-invasive haemodynamic and dyspnoea responses differed between the 30-STST and the 6MWT. However, the lack of test-specific differences between the 6MWT and the 60-STST highlights the strong physiological stimulus elicited by this short-duration test modality. The 60-STST has promising utility as a functional measure of heart and lung capacity within cardiac rehabilitation programs.