Influence of Flooring on Lower Extremity Blood Oxygenation and Volume during Prolonged Standing

Abstract

Prolonged standing is an occupational hazard that may evoke many cardiovascular problems. This study investigates the effects of anti-fatigue mats on hemoglobin levels—related to blood pooling—in the lower extremities during prolonged standing. Fifteen subjects (6 M, 9 F; Age = 26 ± 3 years; BMI = 23.2 ± 2.5 kg/m2) stood for one hour on a hard floor and anti-fatigue mat. Oxygenated (HbO), deoxygenated (HbR), and total (HbT) hemoglobin levels were measured for the soleus muscle using near infrared spectroscopy. A mixed-effects model was performed indicating that time, flooring, and their interaction effect were significantly associated with levels of HbO (time, p<0.0001; floor, p=0.0056; interaction, p=0.0033), HbR (time, p<0.0001), and HbT (time, p<0.0001; floor, p=0.0060; interaction, p=0.0062). Results indicate that hemoglobin levels change with time, and flooring has an effect. Blood pooling seems to be the mechanism. Anti-fatigue mats may have a positive effect on cardiovascular outcomes.