Background: Exercise reduces chronic complications in individuals with diabetes and peripheral vascular diseases. In clinical practice, the use of air insole may reduce peak plantar pressure (PPP), and risk for diabetic foot ulcers (DFUs). However, there is no guideline on selecting air insole pressure for effectively reducing PPP. Therefore, this study aimed to investigate the effects of different air insole pressure on PPP at different walking durations. Methods: We tested 13 participants using repeated measures study design, including 3 air insole pressures (80, 160, and 240 mm Hg) and 2 walking durations (10 and 20 minutes) for 6 walking conditions. PPP values at the first toe, first metatarsal head, and second metatarsal head were calculated. Results: The one-way ANOVA showed significant pairwise differences of PPP at 20 minutes duration in the first metatarsal head between 80 and 240 mm Hg (P = .007) and between 160 and 240 mm Hg (P = .038); in the second metatarsal head between 80 and 240 mm Hg (P = .043). The paired t test confirmed that walking duration significantly has lower PPP at 10 minutes than 20 minutes with 240 mm Hg air insole in the first metatarsal head (P = .012) and the second metatarsal head (P = .027). Conclusion: People at risk of foot ulcers are suggested to wear shoes with 80 mm Hg of air insole for reducing PPP in the first metatarsal head and the second metatarsal head. Moreover, people may avoid wearing the stiffer insole (240 mm Hg) for more than 20 minutes.

Patients with scars face a grave threat to their mental and physical health. Negative pressure has been used for scar therapy in medical care and provides a microenvironment conducive to scar healing while stimulating cell regeneration. Negative pressure may disrupt scar tissue regeneration when the pressure is too high or too low, so finding a suitable negative pressure is important. We hypothesized that different negative pressure magnitudes would affect scar tissue properties differently. This research aimed to provide practical recommendations for scar therapy. This study used three negative pressures (−105 mmHg, −125 mmHg, and −145 mmHg) to compare scar material properties. We measured scar tissue thickness and viscoelasticity with a motor-driven ultrasound indentation system. According to the results of this study, scar thickness is most effectively reduced at a negative pressure of −105 mmHg. In comparison, scar viscoelasticity continuously increases at a negative pressure of −125 mmHg. Negative pressure therapy can be recommended to scar care clinics based on the results of this study.

Background: In the forefoot region, diabetic foot ulcer (DFU) is more likely to develop due to elevated plantar pressure and repetitive loading. This study investigated the effects of different forefoot insole pressures and walking durations on the elasticity of the plantar tissue to identify conditions that may help prevent DFU. Methods: With thirteen healthy participants, we conducted a controlled walking exercise at a speed of 3.6 mph on a treadmill, comparing three different inner pressures of 80, 160, and 240 mmHg with two different walking durations of 10 and 20 min. We measured the elasticity of the first metatarsal head (M1) using a motor-driven indentation system with ultrasound post-walking exercise. We measured the effective Young’s modulus ( E ) for analysis, where E1 is taken from 5% of the initial thickness of the Toe region’s elasticity, E2 is taken from 10% of the initial thickness of the Heel region’s elasticity, and E3 is taken from 15% of the initial thickness of the Linear region’s elasticity. ANOVA and paired t-test analyses are used to find the relation between durations in the post-walking conditions. Results: The effect of the different insole hardnesses using ANOVA indicated that the 240 mmHg insole hardness significantly reduced the stiffness of M1 in E1 ( P = 0.042) and E2 ( P = 0.046), but not in E3 ( P = 0.059). In the paired t-test, no significant differences were found between the 10 and 20 min walking durations for the three insole hardnesses. Conclusion: The study concluded that after a 10-minute walking duration, using 240 mmHg insole hardness has lower stiffness than the recommended stiffness range. These findings highlight the importance of optimizing insole pressure and walking duration in maintaining foot health, and provide evidence to guide the design of functional air insoles to reduce the risk of DFU formation. Trial registration: ClinicalTrials.gov Identifier: NCT06746597. Registered on 2024-12-09 (retrospectively registered).