Prolonged Passive Vs. Active Standing: Influence On Pulse Wave Velocity And Musculoskeletal Outcomes

Prolonged standing behavior demonstrates both beneficial and harmful influences on cardiovascular and musculoskeletal health due to a unidimensional definition of standing in previous research (i.e., all standing is the same). We hypothesize that standing is multidimensional, and the type of standing (passive vs. active) may contribute differently to changes in cardiovascular and musculoskeletal outcomes. PURPOSE: To determine the influence of prolonged passive vs. active standing on pulse wave velocity (PWV) and musculoskeletal outcomes. METHODS: Ten participants (27.7 ± 5.6 yr) enrolled in a randomized crossover study that utilized two conditions of 90 min of PASSIVE or ACTIVE standing at a sit-stand desk. ACTIVE included 10 min of self-guided standing on a dynamic active standing board (Movemate) every 30 min to promote increased lower body muscular activity. Measurements of brachial-femoral PWV (bfPWV) and femoral-ankle PWV (faPWV), as well as 100-point visual analog scales of musculoskeletal discomfort, physical fatigue, and mental fatigue were collected at baseline and following 90 min of standing. All data was analyzed by repeated measures ANOVA (2 within factors, time and condition; alpha = 0.05) and partial eta2 (𝜼;p2) for effect size. RESULTS: A significant time x condition interaction (p = .005, 𝜼;p2 = .60) was observed for faPWV where values decreased over time in ACTIVE (13.8 ± 0.9 to 13.0 ± 1.2 m/s) compared to an increase in PASSIVE (14.9 ± 3.1 to 17.9 ± 4.5 m/s). A significant time x condition interaction with higher values in PASSIVE compared to ACTIVE was observed for physical fatigue (PASSIVE: 11.5 ± 11.4 to 24.7 ± 13.5; ACTIVE: 8.9 ± 9.8 to 14.4 ± 10.6, p = .008, 𝜼;p2 = .56) and mental fatigue (PASSIVE: 13.8 ± 16.2 to 24.2 ± 18.5; ACTIVE: 9.9 ± 11.2 to 10.7 ± 9.3, p = .019, 𝜼;p2 = .48). Though no interaction effect was observed, a significant condition effect was observed for bfPWV (p = .006, 𝜼;p2 = .56) and discomfort (p = .036, 𝜼;p2 = .40). Post hoc analysis revealed no significant difference at baseline between conditions, but a significant Bonferroni-adjusted difference at 90 mins with lower values in ACTIVE for bfPWV (p = .012) but not discomfort (p = .042). CONCLUSIONS: Participation in active standing results in beneficial responses for PWV and musculoskeletal outcomes compared to prolonged passive standing.