ABSTRACT
BACKGROUND: It is essential to better characterize the energetic profile of individuals during very low-intensity physical activity. The objectives of the present study were to determine whether the saver profile from sit-to-stand persists during light physical activity and characterize patterns in substrate utilization from sit-to-stand and during very low-intensity physical activity in healthy men and women. METHODS: Sixty-two healthy adults (38 women) performed an experimental sequence that corresponded to 15-minute sitting (SIT1), followed by 15-minute standing (STAND), 15-minute sitting again (SIT2), and finally 15 minutes of light cycling. Continuous indirect calorimetry was allowed to calculate energy expenditure (EE) and respiratory quotient through the entire sequence. Savers and nonsavers (<5% and ≥ 5% increase in EE from sitting to standing, respectively) were determined. RESULTS: There was an interaction effect in EE between savers and nonsavers through the whole sequence (P = .008). Only nonsavers (71%) exhibited a significant increase in EE from SIT1 to STAND (P < .001). Nonsavers and savers significantly increased EE during 15 minutes of light cycling relative to sitting or standing (P < .001), without any difference between groups. The percentage of change in respiratory quotient from SIT1 to STAND was significantly different between the 2 groups, with increased values in savers and decreased values in nonsavers (P = .03). Significantly lower values in respiratory quotient and EE were found during 15 minutes of light cycling in women compared with men (P < .001). CONCLUSIONS: It is essential to determine individuals' energetic phenotype to determine those who may benefit more from strategies such as standing or light physical activity. The sexual dimorphism in terms of substrate use during such exercise should be considered.
Subject(s)
Calorimetry, Indirect , Energy Metabolism , Exercise , Sitting Position , Standing Position , Humans , Energy Metabolism/physiology , Male , Female , Adult , Exercise/physiology , Young Adult , Oxygen Consumption/physiologyABSTRACT
CONTEXT: In addition to the low energy expenditure induced by sedentary behaviors such as sitting, it has been shown that intense cognitive work can lead to an increase in food intake. Walking Desk provide the opportunity for office workers to replace prolonged sitting at work with light intensity physical activity. OBJECTIVE: To compare the effects of sitting vs standing vs walking during a cognitive task on energy intake, appetite sensations, food reward and overall energy balance. METHODS: Fifteen normal weight (BMI: 24.1 ± 1.2 kg m-2) young men (23.4 ± 2.1 years) randomly performed three conditions: sitting desk (SitD), standing desk (StD) and walking desk (WD), while performing a 45-min cognitive task. Energy expenditure was measured by indirect calorimetry, regular appetite sensations were assessed using visual analogue scales, energy intake measured during an ad libitum meal and the relative energy intake calculated. Pre and post-test meal food reward was evaluated through the Leeds Food Preference Questionnaire. RESULTS: Relative energy intake decreased by 150 kcal in WD compared with SitD, however it did not reach statistical significance. There were no differences in appetite sensations nor food reward between the three conditions. Energy expenditure was significantly higher in WD (141.8 ± 13 kcal) than in SitD (78.7 ± 5 8 kcal) and StD (85.9 ± 8 kcal) (p ≤ 0.05). CONCLUSION: Walking desk use can decrease sedentary time while working without any appetitive compensation. The small reduction in energy balance with walking while working could induce significant health benefits if repeated over time. Future longer studies need to clarify whether active desks can contribute to the prevention or management of weight gain.
Subject(s)
Cognition , Humans , Male , Young Adult , Appetite , Cognition/physiology , Energy Intake , Energy Metabolism/physiology , Sedentary Behavior , Walking/physiology , AdultABSTRACT
OBJECTIVES: The aim of this study was to evaluate the effects of a portable pedal machine intervention (60 minutes per working day) for 12 weeks on healthy tertiary employees' cardiometabolic risk factors. METHODS: Anthropometric parameters, body composition, cardiometabolic/inflammatory markers, physical fitness, physical activity, and sedentary time measured before and after the intervention were compared between office healthy workers who used a portable pedal machine (INT, n = 17) and those who did not (CTRL, n = 15). RESULTS: The INT group improved Δultrasensitive C-reactive protein ( P = 0.008), Δtotal cholesterol ( P = 0.028), and Δlight-density lipoprotein cholesterol ( P = 0.048) compared with the CTRL group (Δ: T1-T0). The intervention reduced daily sitting time ( P ≤ 0.01) and increased time spent at light intensity ( P ≤ 0.01) and moderate-to-vigorous ( P ≤ 0.01) physical activity compared with baseline values. CONCLUSIONS: These findings suggest that promoting physical activity during workdays can reduce the negative health effects of spending too much time sitting and inactive.