MEGAN C. NELSON, MADELINE P. CASANOVA, CHANTAL A. VELLA

To investigate differences in energy expenditure (EE), heart rate (HR), productivity, fatigue, and pain while performing desk work while sitting (SIT), standing (STAND), and standing on a balance board (BOARD). Thirty healthy adults (60% female; age 39.7 ± 11.8 y; BMI 26.7 ± 5.0 kg·m) employed in sedentary-based jobs volunteered for this randomized crossover trial. Participants performed typing work in three different positions: SIT, STAND, and BOARD; each condition lasting 30 min. Oxygen consumption (VO2) was measured via indirect calorimetry and EE was calculated using respiratory quotient and corresponding caloric equivalent values. Productivity was quantified by measuring words typed per min, accuracy, and typing mistakes. Overall feelings of fatigue and pain were self-reported three times during each position using validated 10-cm visual analog scales. Repeated measures ANOVA were used to assess differences in outcome variables across conditions. VO2 was significantly different among all conditions regardless of current standing desk use (SIT 3.35 ± 0.53; STAND 3.77 ± 0.48; BOARD 3.92 ± 0.54 mL·kg·min, p<0.001). EE (kcal·min) also differed (p<0.001) among SIT (1.27 ± 0.22), STAND (1.42 ± 0.26) and BOARD (1.48 ± 0.29). Compared to sitting (67 ± 9 bpm), HR was higher in STAND (76 ± 11 bpm) and BOARD (76 ± 11 bpm, p<0.001). Measures of productivity were not different across conditions (p>0.05). Fatigue progressively increased over each 30 min condition whereas pain in SIT and BOARD increased from min 10 to 20, then leveled off between min 20 to 30. For STAND, pain continued to increase over time. Compared with sitting, a balance board may be effective for increasing EE without interfering with productivity in an occupational setting.