There is evidence that physical activity (PA) levels are declining in English children. Sedentary screen based media activities, including computer use and video game play have been linked to low PA levels and unhealthy energy intake (EI). These behaviours appear to be particularly prevalent in boys during mid-to-late childhood. Recent laboratory-based studies have found active video games can increase children’s energy expenditure (EE) and PA levels to moderate to vigorous levels, in comparison to matched conditions such as resting and seated video game play and so could increase children’s PA. However, the previous active video gaming studies have utilised various protocols that probably do not accurately reflect the real life active video gaming practices of children. Recently it has been established that there is EI in adolescents during active video gaming. If this is so, the EI during active video gaming could potentially counteract the EE from active video game play. The purpose of this thesis therefore, was to establish the acute appetite, EI and PA responses to active video gaming, in 8-11 y boys. There is sparse information regarding the habitual active video gaming behaviours of children during mid-to-late childhood. Consequently, in study one a questionnaire was designed specifically, to understand the real-life active video gaming practices of 40 7-11 yr-olds. By utilising the survey findings, in study two an acute intervention was designed to investigate the subjective appetite sensations (hunger, prospective food consumption and fullness), EI and PA in response to active video gaming in 21 8-11 yr-old boys. Each boy completed four individual 90 min gaming bouts in a randomised order which were; 1) seated video gaming no food or drinks, 2) active video gaming no food or drinks, 3) seated video gaming, food and drinks offered ad libitum and 4) active video gaming, food and drinks offered ad libitum. The study determined that there were no differences in acute sensations of hunger, prospective food consumption and fullness, or EI (MJ) between the seated and active video gaming bouts during which foods and drinks were offered ad libitum (bouts 3 and 4). Physical activity levels due to active video gaming were light and from seated video gaming were sedentary. Energy intake during both bouts was greater than the estimated EE, thus producing a positive relative energy balance state in the boys. As subjective appetite findings did not explain the high EI during both seated and active video gaming, the objective study of appetite was necessary. A previous adult study had established good reproducibility in GLP-17-36, glucagon, leptin and insulin by using the less invasive fingertip capillary sampling. Since fingertip capillary sampling had not been utilised to measure plasma concentrations of the above mentioned hormones in children during gaming, in study three, preliminary testing established good reliability for fasting plasma GLP-17-36 and blood glucose in 8- 11 yr-old boys. Enabling study three to compare acute satiety related signalling, subjective appetite, EI and PA in 21 8-11 yr-old boys, in response to one bout of active video gaming and one bout of seated video gaming, during which food and drinks were offered ad libitum. The satiety-related signals, namely plasma GLP-17-36 and blood glucose were measured alongside subjective appetite sensations and EI during active and seated video game play and in a post-gaming test meal. A significant increase in glucose showed the boys had consumed a greater proportion of carbohydrate (CHO) during active video gaming. However, as more total energy was consumed during seated video gaming, and plasma GLP-17-36 was higher during active video gaming, according to the ‘glucostatic theory’, there may have been a satiety response. The satiety signals may not have been strong enough to override the hedonic response to food intake, especially as fullness sensations were higher during active video gaming. Physical activity levels were light due to active video gaming and sedentary from seated video gaming and so on cessation of both bouts, the relative energy balance of the boys was positive. The positive relative energy balance state was then not compensated for by a reduction in EI in a post-gaming test meal. Instead, the additional EI resulted in an increase in the positive relative energy balance state, of the 8-11 yr-old boys. The overall findings of this thesis established that EI appears to be commonplace in the majority of 8-11 yr-old children during active video gaming. Parents should encourage their children to play active, rather than seated video games to reduce sedentary time and also discourage EI during game play.
|Publication status||Accepted/In press - Jun 2015|