Effect of Acute Exercise and Cycling Desk on Energy Intake and Appetite Response to Mental Work: The CORTEX Study

BACKGROUND

While mental work has been shown to favor overconsumption, the present study compared the effect of a cognitive task alone, followed by acute exercise, or performed on a cycling desk, on short-term food intake and appetite in adults.

METHODS

A total of 19 normal-weight adults randomly completed: resting session (CON), 30-minute cognitive task (CT), 30-minute cognitive task followed by a 15-minute high-intensity interval exercise bout (CT-EX), and 30-minute cognitive task performed on a cycling desk (CT-CD). Energy expenditure was estimated (heart rate-workload relationship), and energy intake (EI; ad libitum) and appetite (visual analog scales) were assessed.

RESULTS

Energy expenditure was higher in CT-EX (P < .001) compared with the other conditions and in CT-CD compared with CON and CT (P < .01). EI was higher in CON (P < .05) and CT-CD compared with CT (P < .01). Relative EI was higher in CON compared with CT (P < .05) and lower in CT-EX compared with CT, CT-CD, and CON (all Ps < .001). Area under the curve desire to eat was higher in CON compared with CT (P < .05) and CT-EX (P < .01). Area under the curve prospective food consumption was higher in CON compared with CT-EX (P < .01). Overall composite appetite score was not different between conditions.

CONCLUSION

While cycling desks are recommended to break up sedentary time, the induced increase in energy expenditure might not be enough to significantly reduce overall short-term relative EI after mental work.

Does Posture Influence the Stroop Effect?

Rosenbaum, Mama, and Algom (2017) reported that participants who completed the Stroop task (i.e., name the hue of a color word when the hue and word meaning are congruent or incongruent) showed a smaller Stroop effect (i.e., the difference in response times between congruent and incongruent trials) when they performed the task standing than when sitting. We report five attempted replications (analyzed sample sizes: N = 108, N = 108, N = 98, N = 78, and N = 51, respectively) of Rosenbaum et al.'s findings, which were conducted in two institutions. All experiments yielded the standard Stroop effect, but we failed to detect any consistent effect of posture (sitting vs. standing) on the magnitude of the Stroop effect. Taken together, the results suggest that posture does not influence the magnitude of the Stroop effect to the extent that was previously suggested.

Comparing Cognitive Control Performance During Seated Rest and Self-Paced Cycling on a Desk Bike in Preadolescent Children

BACKGROUND

Although active workstations, such as desk bikes, have proven to be beneficial for health, there is limited information regarding their effects on children's acute cognitive performance during self-paced exercise.

METHODS

This study used a within-subjects, fully counterbalanced design with a sample of 38 preadolescent children (mean age = 12.50 y, SD = 0.62; 43% male), who performed cognitive tests while being seated or while cycling for 45 minutes with a 7-day interval. Effects of using a desk bike were evaluated on cognitive control: verbal and visuospatial working memory capacities were tested, and inhibition was assessed using a modified flanker task. In addition, subjective task experience was explored using self-report measures.

RESULTS

Cognitive control performance was not degraded but also not improved with the short-term use of desk bikes. Because of the null effects, there is no direction and magnitude of the outcomes to discuss.

CONCLUSIONS

These findings suggest that schools can successfully implement desk bikes to increase physical activity and reduce sedentary time among children without compromising cognitive control processes necessary for academic achievement.

Implementation of Active Workstations in University Libraries-A Comparison of Portable Pedal Exercise Machines and Standing Desks

Sedentary behaviors are an important issue worldwide, as prolonged sitting time has been associated with health problems. Recently, active workstations have been developed as a strategy to counteract sedentary behaviors. The present study examined the rationale and perceptions of university students’ and staff following their first use of an active workstation in library settings. Ninety-nine volunteers completed a self-administered questionnaire after using a portable pedal exercise machine (PPEM) or a standing desk (SD). Computer tasks were performed on the SD (p = 0.001) and paperwork tasks on a PPEM (p = 0.037) to a larger extent. Men preferred the SD and women chose the PPEM (p = 0.037). The appreciation of the PPEM was revealed to be higher than for the SD, due to its higher scores for effective, useful, functional, convenient, and comfortable dimensions. Younger participants (<25 years of age) found the active workstation more pleasant to use than older participants, and participants who spent between 4 to 8 h per day in a seated position found active workstations were more effective and convenient than participants sitting fewer than 4 h per day. The results of this study are a preliminary step to better understanding the feasibility and acceptability of active workstations on university campuses.