Acute Compensatory Responses to Interrupting Prolonged Sitting With Intermittent Activity in Preadolescent Children

Exploring Children's Self-Reported Activity Compensation: The REACT Study

PURPOSE

Previous research has focused on device-based measures of activity compensation, with little understanding of how children perceive potential compensatory responses to activity or inactivity, or whether these change after periods of activity or inactivity. The aim of this study was (a) to explore the alignment between children's self-reported usual compensation and compensation recall after experimental conditions and (b) to examine sex differences.

METHODS

In total, 360 children (47% boys) participated in at least one of three experimental conditions over 6 wk: (a) restricted physical activity (PA; indoor play), (b) imposed moderate- to vigorous-intensity PA (MVPA; sports class), and (c) imposed light-intensity PA (LPA; standing lesson). Before the first condition, children reported their "usual compensation" behavior to examples of restricted/imposed PA, and 2-3 d after each experimental condition, they completed a recall measure of their compensation after the condition. Multilevel regression models were conducted to determine whether children's perceptions of "usual compensation" score were associated with recalled compensation score after imposed or restricted PA. Additional models were fitted for sex-specific associations.

RESULTS

Overall and among girls, the usual compensation score was positively associated with the compensatory recall score for the additional MVPA and LPA conditions ( P < 0.0005; e.g., they thought they would usually compensate for additional MVPA and then perceived that they compensated after additional MVPA). A negative association was seen in the restricted activity condition among girls ( P = 0.03). All associations in the boys' analyses were statistically nonsignificant.

CONCLUSIONS

These findings suggest some alignment between children's self-reported usual compensation and compensation recall after imposed changes to routine activity. Future research should consider device-measured comparisons and identify characteristics of children at risk of activity compensation in future interventions.

Psychological Responses to Intermittent Activities in Children With and Without Asthma

PURPOSE

The purpose of this study was to examine the psychological responses to intermittent activities of varying intensities and types among children with and without asthma.

METHODS

A total of 37 children and adolescents (51% male, aged 8-16 y, 54% nonwhite, and 54% without asthma) participated in this study. Participants completed 5 exercises in the same order: self-paced walking, resistance activities, dance video, gamified obstacle course, and step test. In-task mood was assessed using the Feeling Scale, in-task perceived exertion was assessed via the ratings of perceived exertion scale, and postactivity enjoyment was assessed using the Physical Activity Enjoyment Scale.

RESULTS

There was a significant main effect of exercise type on mood (P < .001), ratings of perceived exertion (P < .001), and enjoyment (P < .002). There was not a significant main effect of asthma status on mood, ratings of perceived exertion, or enjoyment (Ps > .05). Children with asthma reported significantly lower in-task mood during the step exercise (P < .037) and reported significantly lower postactivity enjoyment after the walk and obstacle course exercises (Ps < .03).

CONCLUSIONS

Regardless of differences by asthma status for in-task mood during the obstacle course and for postactivity enjoyment during the walk and step exercises, both children with and without asthma reported high in-task mood and postactivity enjoyment during all 5 exercises.

Exploring activity compensation amongst youth and adults: a systematic review

BACKGROUND

Globally, significant efforts have focused on increasing physical activity and reducing sedentary behaviour in youth and adults across a range of settings (e.g., schools, workplaces, community, and home). Despite this, interventions have had varied efficacy and typically have failed to sustain changes in behaviours over time. One explanation that has been put forth to explain the mixed success of interventions is activity compensation. However, little is known about activity compensation, including whether compensation occurs, and perceptions and potential mechanisms of activity compensation. Understanding activity compensation would assist in tailoring and targeting of potential intervention strategies. The primary aim of this review was to synthesise research that has investigated activity compensation in youth and adults. The secondary aim was to identify potential reasons for and/or awareness of compensatory changes that may have occurred.

METHODS

An electronic search of the EBSCOhost (via Academic Search Complete, CINAHL Complete, Education Source, Health Source: Nursing/Academic Edition, PsycINFO, SPORTdiscus with Full Text), MEDLINE Complete, Global Health, EMBASE, Scopus and Web of Science databases up to May 2021 was conducted. Quality assessment of included quantitative studies used a modified compensation-specific McMaster Quality Assessment Tool.

RESULTS

A total of 44 studies met the inclusion criteria (22 = adult populations; 22 = youth populations) and were classified as (1) quantitative (n = 31); (2) combination of quantitative and behavioural (n = 11); (3) behavioural only (n = 1); and (4) qualitative (n = 1). Of the 42 studies that included a quantitative component, 11 (26%) reported compensation occurred. Within the 13 studies examining specific behaviours, 35 behaviours were assessed, and evidence of compensation was inconsistent. Compensation mechanisms included fatigue, time constraints, lack of motivation, drive to be inactive, fear of overexertion, and autonomous motivation.

CONCLUSION

Little evidence of compensation was reported in the included quantitative studies; however, inconsistencies between studies makes comparisons difficult. There was considerable variability in the types of behaviours assessed in quantitative studies, and few studies examined potential compensatory mechanisms. Future research, using compensation specific study designs, methods, and analytic techniques, within different population sub-groups, should address these evidence gaps.

Acute Effects of Intermittent Physical Activity on Perceptions of Exercise-Related Fatigue in Children

PURPOSE

To investigate the acute effects of intermittent activity performed at varying intensities on the perceptions of exercise-related fatigue in children.

METHODS

A total of 30 children completed 4 experimental conditions in random order, which consisted of 8 hours of sitting interrupted with 20 two-minute low-, moderate-, or high-intensity activity breaks or 20 two-minute sedentary breaks. The perceptions of exercise-related fatigue were determined via the Subjective Exercise Experience Scale at the beginning (0 breaks), middle (after 10 breaks), and end (after 20 breaks) of each condition.

RESULTS

The average heart rate was significantly higher with increasing exercise intensity (sedentary: 89.6 ± 1.2 beats/min, low: 114.6 ± 1.8 beats/min, moderate: 147.2 ± 1.8 beats/min, and high: 172.3 ± 1.8 beats/min, P < .0001). There was no significant main effect of condition (sedentary: -0.5 ± 0.6, low: -1.0 ± 0.7, moderate: -0.2 ± 0.5, and high: -0.6 ± 1.2; P = .86) and time (10-0 breaks: -0.7 ± 0.5 and 20-0 breaks: -0.5 ± 0.5; P = .45), nor time by condition interaction (P = .99) on change in exercise-related fatigue.

CONCLUSIONS

Incorporating intermittent activity into physical activity programs may help to reduce barriers to regular exercise by minimizing perceptions of exercise-related fatigue in children.

Acute Effects of Interrupting Prolonged Sitting With Intermittent Physical Activity on Blood Pressure in Preadolescent Children

PURPOSE

To compare the acute effects of intermittent physical activity (PA) across 4 different intensities on blood pressure.

METHODS

Thirty children (12 males and 18 females; aged 7-11 y; 33% overweight/obese; 53% nonwhite) completed 4 experimental conditions in random order: 8 hours sitting interrupted with 20, 2-minute low-, moderate-, high-intensity PA breaks, or sedentary screen-time breaks. PA intensity corresponded with 25%, 50%, and 75% of heart rate reserve. Blood pressure was measured during each condition in the morning (0800 h), noon (1200 h), and afternoon (1600 h).

RESULTS

There were no significant differences across conditions for systolic blood pressure (SBP; all Ps > .05). There was a significant effect of time with SBP decreasing throughout the day for all conditions (average morning SBP: 106 [1] mm Hg, average noon SBP: 101 [2] mm Hg, average afternoon SBP: 103 [1] mm Hg; P = .01). There were no significant effects of condition or time on diastolic blood pressure (all Ps > .05).

CONCLUSION

While sedentary behavior is known to be associated with hypertension in both adults and children, a single bout of prolonged sitting may be insufficient to produce hypertensive effects in otherwise healthy children. Future research should examine the appropriate dose of intermittent PA to accrue hypotensive responses in preadolescent children.

The effects of interrupting prolonged sitting with intermittent activity on appetite sensations and subsequent food intake in preadolescent children

Background

Short-term and long-term exposure to prolonged sitting is associated with excess food intake and weight gain in children. Interrupting prolonged sitting with low-intensity activity has been shown to not alter hunger, satiety, or food consumption in children, however it is unclear whether interrupting sitting with high-intensity activity will alter appetite regulation in children.

Purpose

The purpose of this study was to examine the acute effects of interrupting prolonged sitting with intermittent activity performed at varying intensities on hunger, satiety, prospective food consumption (PFC), and food intake in preadolescent children.

Methods

Thirty-nine children (ages 7–11 years, 54% female, 33% overweight/obese) completed four experimental conditions in random order: 8 hours of sitting interrupted with 20, 2-minute low-, moderate-, or high-intensity activity breaks or 20, 2-minute sedentary screen time breaks. Exercise intensity corresponded with 25%, 50% and 75% of heart rate reserve, respectively. Hunger, satiety, and PFC were assessed using the Visual Analog Scale, at five time points (pre- and post-breakfast, pre- and post-lunch, and pre-dinner) during each experimental condition. Dietary compensation was assessed as total caloric intake during a post-condition dinner standardized to provide 70% of estimated daily energy requirements.

Results

There was a significant effect of time on hunger, satiety, and PFC throughout each condition day (p< 0.001). There were no differences across conditions for hunger (sedentary: 4.9±0.3 cm, low: 5.0±0.3 cm, moderate: 5.1±0.3 cm, high: 5.1±0.3 cm, p>0.05), satiety (sedentary: 4.7±0.3 cm, low: 4.4±0.3 cm, moderate: 4.6±0.3 cm, high: 4.2±0.3 cm, p>0.05), and PFC (sedentary: 4.9±0.3 cm, low: 4.7±0.3 cm, moderate: 4.9±0.3 cm, high: 5.0±0.3 cm, p>0.05). There were no significant differences in post-activity food intake across conditions (sedentary: 1071.9±53.6 kcals; low: 1092.6±43.4kcals; moderate: 996.2±54.6kcals; high: 1138.7±62.8kcals, p>0.05). However, there was a significant effect of condition on energy balance (sedentary: +61.4±65.9 kcals, low: +74.9±57.6 kcals, moderate: -58.3±62.8 kcals, high: -391.2±77.9 kcals; p<0.001). There were no significant effects of weight status on hunger, satiety, PFC, post-activity food intake, and mean energy balance across conditions (all p’s>0.05).

Conclusions

Interrupting prolonged sitting with physical activity of any intensity does not alter appetite sensations and subsequent food consumption in children. These data suggest that interventions targeting prolonged sitting with high-intensity intermittent activity may be an effective strategy to increase physical activity energy expenditure without increasing food intake, allowing for a short-term energy deficit in both healthy weight and overweight/obese children. Future studies should examine the long-term effects of interrupting prolonged sitting with activity on food consumption and weight status in preadolescent children.