Energy intake adaptations to acute isoenergetic active video games and exercise are similar in obese adolescents.

ORIGINAL ARTICLE

Energy intake adaptations to acute isoenergetic active

video games and exercise are similar in obese adolescents

JP Chaput

, C Schwartz

, Y Boirie

, M Duclos

, A Tremblay

and D Thivel

BACKGROUND/OBJECTIVES: Although the impact of passive video games (PVGs) on energy intake has been previously explored

in lean adolescents, data are missing on the nutritional adaptations to passive and active video games (AVGs) in obese adolescents.

It is also unknown whether isoenergetic AVGs and exercise (EX) differently affect food consumption in youth.

SUBJECTS/METHODS: Nineteen obese adolescent boys (12–15 years old) had to complete four 1-hour sessions in a crossover

manner: control (CON; sitting on a chair), PVG (boxing game on Xbox 360), AVG (boxing game on Xbox Kinect 360) and EX (cycling).

The EX was calibrated to generate the same energy expenditure as the AVG session. Energy expenditure was measured using a

K4b2 portable indirect calorimeter. Ad libitum food intake (buffet-style meal) and appetite sensations (visual analogue scales) were

assessed after the sessions.

RESULTS: As expected, mean energy expenditure was similar between AVG (370 ± 4 kcal) and EX (358 ± 3 kcal), both of which were

signi

ficantly higher than PVG (125 ± 7 kcal) and CON (98 ± 5 kcal) (Po0.001). However, ad libitum food intake after the sessions was

not signi

ficantly different between CON (1174 ± 282 kcal), PVG (1124 ± 281 kcal), AVG (1098 ± 265 kcal) and EX (1091 ± 290 kcal).

Likewise, the energy derived from fat, carbohydrate and protein was not significantly different between sessions, and appetite

sensations were not affected.

CONCLUSIONS: Energy intake and food preferences after an hour of AVG or PVG playing remain unchanged, and isoenergetic

sessions of AVG and EX at moderate intensity induce similar nutritional responses in obese adolescent boys.

European Journal of Clinical Nutrition (2015)

69, 1267–1271; doi:10.1038/ejcn.2015.31; published online 25 March 2015

INTRODUCTION

In addition to the increasing availability and consumption of

energy-dense foods and the lack of physical activity, sedentary

behaviors have been pointed out to explain the high rates of

obesity and their metabolic complications.

Many children today

spend prolonged periods of time engaged in screen-based

activities such as TV watching, computer use and video game

playing,

which have been associated with increased body

weight and adverse health outcomes.

The implication of sedentary activities in the progression of

weight gain has been primarily attributed to the low-energy

expenditure of these activities.

_{However, computer-related}

activities have been shown to promote overconsumption of food

in young adults,

and a recent experimental study found

increased energy intake in youth after passive video game (PVG)

playing.

In their work, Chaput et al.

asked healthy lean male

adolescents to play seated video games for 1 h and found an

80 kcal increase in energy consumption compared with a control

session of quiet sitting. This increase in food intake was not

accompanied by increased subjective appetite sensations or

increased appetite-related hormones,

suggesting that other

factors may be at play.

It has been suggested that, despite this increased food intake

induced by playing PVGs, the use of active video games (AVGs)

could be better at promoting a negative energy balance given their

ability to enhance energy expenditure.

Although it has been

effectively shown that AVGs increase acute energy expenditure,

some interventional studies failed to

find any body weight loss in

obese youth by using AVGs instead of exercise (EX) training.

_This

observation might be explained by some possible compensation in

food intake and/or physical activity adjustments.

Furthermore,

although nutritional adaptations to EX have been observed in

obese children and adolescents,

we found no evidence

regarding potential energy intake adaptations to AVGs in this

population. It is also unknown whether isoenergetic AVGs and EX

differently affect food intake in youth.

The aim of the present work was thus to compare the effects of

acute sessions of PVGs, AVGs and physical EX on energy intake, food

preferences and appetite sensations in obese male adolescents.

METHODS

Participants

A total of 19 obese (according to Cole et al.20) adolescent boys aged 12–15 years (Tanner stage 3–4) were recruited through pediatric consultations (Clermont-Ferrand University Hospital and Romagnat Children Medical Center, France). All adolescents had to be free of any medication that could interfere with the protocol, could not present any contraindications to

1

Healthy Active Living and Obesity Research Group, Children’s Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada;2

School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada;3Clermont University, Blaise Pascal University, EA 3533, Laboratory of the Metabolic Adaptations to Exercise under Physiological and Pathological Conditions (AME2P), Clermont-Ferrand, France;4

Department of Human Nutrition, Clermont-Ferrand University Hospital, G. Montpied Hospital, Clermont-Ferrand, France;5

INRA, UMR 1019, Clermont-Ferrand, France;6

University Clermont 1, UFR Medicine, Clermont-Ferrand, France;7

CRNH-Auvergne, Clermont-Ferrand, France;8

Department of Sport Medicine and Functional Explorations, Clermont-Ferrand University Hospital, G. Montpied Hospital, Clermont-Ferrand, France and9

Department of Kinesiology, Faculty of Medicine, Laval University, Quebec City, Quebec, Canada. Correspondence: Dr D Thivel, Clermont University, Blaise Pascal University, EA 3533, Laboratory of the Metabolic Adaptations to Exercise under Physiological and Pathological Conditions (AME2P), campus des cezeaux, BP 80026, Aubière Cedex F-63171, France. E-mail: David.Thivel@univ-bpclermont.fr

Received 8 December 2014; revised 29 January 2015; accepted 3 February 2015; published online 25 March 2015

physical activity and had to be engaged in_{o2 h of physical activity per} week. All adolescents and their legal representative received information sheets and signed consent forms as requested by the ethical authorities (AU1033). This protocol is registered as a clinical trial (clinicaltrials.gov: NCT01912300).

Study protocol

After a medical inclusion visit to control for the ability of the adolescents to complete the study, they were asked to perform a submaximal aerobic test and their body composition was assessed by dual-energy X-ray absorptiometry. The adolescents were then asked to visit the laboratory on four different occasions separated by at least 7 days to undergo different experimental sessions (within-subject crossover design): (1) a control (CON) session; (2) a PVG session; (3) an AVG session; and (4) an EX session. On each of the four occasions the adolescents had to join the laboratory at 08:00 am where they received a standardized breakfast respecting the nutritional recommendations (same composition and calorie content as previously detailed, Thivel et al.19,21). At 10:30 am they were asked to complete one of the following activities: stay seated at rest for 1 h (CON); play a PVG for 1 h; play an AVG for 1 h; or complete a cycling EX. Heart rates were recorded during the four sessions using heart rate monitors. Thirty minutes after the sessions, participants were served an ad libitum buffet-style meal and their appetite was assessed at regular intervals throughout the day.

The order of the session had to be half-randomized in order to have AVG and EX isoenergetic. To do so, the randomization was repeated until the AVG session was placed before the EX session in order to match the EX duration and to make them elicit the same energy expenditure. Energy expenditure was assessed during AVG using a portable indirect calorimeter (K4b2), whereas it was estimated during EX, PVG and CON using heart rate recording (based on the results of the submaximal test). Ad libitum lunch time energy intake and food preferences were assessed and appetite sensations were questioned at regular intervals.

Anthropometric and body composition measurements

A digital scale was used to measure body weight to the nearest 0.1 kg, and barefoot standing height was assessed to the nearest 0.1 cm using a wall-mounted stadiometer. Body mass index was calculated as body weight (kg) divided by height squared (m2_{). Fat mass and fat-free mass were}

assessed using dual-energy X-ray absorptiometry following standardized procedures (QDR4500A scanner, Hologic, Waltham, MA, USA).

Basal metabolic rate

The Basal Metabolic rate of the adolescents was estimated using the equation developed for obese adolescents by Lazzer and collaborators in 2006, based on the participants' body composition, as follows:22

BMR KJð Þ ¼ Sex ´ 909:12ð Þ - Age ´ 107:48ð Þ þ LeanMass ´ 68:39ð Þ þ FatMass ´ 55:19ð Þ þ 3631:23 ð2Þ where sex = 1 for male, BMR is expressed in KJ (and then concerted in kcal in Table 1), age in years, weight in kg, stature in meters, and LM and FM in kg.

Submaximal aerobic capacity

The participants’ submaximal aerobic capacity was assessed during a graded cycling test performed at least 1 week before the experimental session. The test was composed of four stages of 4 min each, starting from 30 W with an increment of 15 W each. An electromagnetically braked cycle ergometer (Ergoline, Bitz, Germany) was used to perform the test. VO2and

VCO2were measured breath-by-breath through a mask connected to O2

and CO2 analyzers (Oxycon Pro-Delta, Jaeger, Hoechberg, Germany).

Calibration of gas analyzers was performed with commercial gases of known concentration. Ventilatory parameters were averaged every 30 s. Electrocardiography was also used for the duration of the tests. This test was performed under the supervision of an accredited medical doctor.

Description of the experimental sessions

CON session. For an hour (from 10:30 am to 11:30 am) the participants remained seated on a comfortable chair. They were not allowed to talk, read, watch TV or complete any intellectual tasks.

PVG. From 10:30 am to 11:30 am the participants had to play a PVG on an Xbox 360 (Microsoft, Redmond, WA, USA). All participants had to play a boxing game that was selected on the basis that the game is easy to learn, popular and can be played in an hour. Instructions on how to play the game were given to the participants earlier.

AVG. From 10:30 am to 11:30 am the adolescents had to play an AVG on an Xbox Kinect 360 (Microsoft). A boxing game was selected (Kinect sport device) as it is an easy game to play and as it had to match the PVG session. During this hour of AVG, the participants were equipped with a K4b2 portable indirect calorimeter to measure their oxygen consumption. The K4b2 was used to measure VO2, energy expenditure and related

cardiorespiratory parameters on a breath-by-breath basis. The K4b2 device has been used in similar populations during various kinds of physical activities,23_{as well as during AVG,}24_{and has given reliable results.}

EX session. From 10:30 am the adolescents were asked to complete a cycling EX set at moderate intensity (~65% of their estimated VO2max

using the results from the submaximal test and extrapolating to their individual theoretical maximal heart rate). The duration of the EX was individually calculated so that the energy expended during the cycling bout was equivalent to the one measured during AVG. The intensity was controlled using heart rate records and the workload imposed on the ergocycle (using the results from the submaximal aerobic capacity testing and calculating the workload corresponding to their estimated VO2max).

Although this method has been used in several previous studies to calibrate the energy expended during the EX (with similar populations), this remains an indirect method that is less accurate than direct technics such as indirect calorimeters (such as the K4b2 used during AVG). This was, however, the best available solution at this time because of practical reasons.

Energy intake

At 8:30 am, a standardized breakfast was offered to the adolescents. The breakfast was prepared by the investigation team in accordance with nutritional recommendations, and it represented 504 kcal as previously detailed.19,21_{The exact same breakfast (in terms of energy content and}

food composition) was given to every participant during each experi-mental condition and they had to consume it entirely (same breakfast for every participants, during every session). As they received the breakfast in the laboratory, a member of the investigation team ensured that the adolescents consumed it all. The methodology employed for the breakfast has been previously published and detailed.19,24_{Thirty minutes after the}

end of the experimental session an ad libitum lunch was offered to the participants. The composition of the buffet meal was the same for all participants and conformed to the adolescents_{’ tastes as determined by a} food questionnaire completed prior to the experimental sessions. Top-rated items were avoided to limit overconsumption. The buffets offered to the participants were identical for the four sessions. Participants were told to eat until satisfied; additional food was provided if desired. Food consumption was weighed and recorded by investigators (Bilnut 4.0 SCDA Nutrisoft software, La Freissinouse, France) to calculate total energy intake. The proportion of total energy intake derived from fat, carbohydrate and protein was calculated using the same nutritional software used to assess

Table 1. Population characteristics

Mean ± s.d. Age (years old) 14.5± 0.8 Weight (kg) 91.0_{± 9.5} BMI (kg/m2) 32.19± 3.05 BMIz-score 2.23_{± 0,24} FM (%) 38.07± 2.68 FFM (kg) 55.0± 4.8 BMR (kcal) 2068± 140 Abbreviations: BMI, body mass index; BMR, estimated basal metabolic rate; FFM, fat-free mass; FM, fat mass.

energy intake. The methodology behind the ad libitum meals and assessment of energy intake were described previously.19

Subjective appetite sensations

At regular intervals throughout the day, starting from 8:00 am, participants were asked to rate their hunger, fullness and prospective consumption using visual analogue scales (of 100 mm) whose reliability has been established.25Participantsfilled in the visual analogue scales before and after theirfirst breakfast, before and after the experimental sessions, before and after lunch, and 15, 30, 60, 90 and 120 min after lunch. This method has previously been used and validated among obese adolescents to evaluate their appetite.18,19,26

Perceived exertion

After AVG and EX, the adolescents were asked to rate their perceived exertion using the Children’s Effort Rating Table utilized in the study by Williams et al.27This scale was elaborated using a range of items from 1 to 10, with number 1 corresponding to an extremely easy EX, and an effort leading the subject to interrupt the test because of its difficulty being indicated as 10. At the end of the study they were asked which one of the EX or AVG conditions was the most difficult to them.

Statistical analysis

On the basis of previously published data, the power calculation analysis showed that data from 18 subjects gave us a power (1-_{β) of 0.9, which was} sufficient to show changes in energy intake as low as 5%, with an α of 0.05 (repeated-measures analysis of variance; ANOVA). Statistical analyses were performed using Statview 5.0 (SAS Institute, New York City, NY, USA). Results are expressed as mean (s.d.). The distribution of the data was tested using the Smirnov_{–Kolmogorov test prior to analysis and data did not} require any transformation prior to analysis. Paired t-tests were used to compare the rate of perceived exertion between EX and AVG. Repeated-measures ANOVA were used to compare energy intake and macronutrient preferences, energy expenditure and mean heart rate and appetite sensation AUC between sessions. The level of significance was set at Po0.05.

RESULTS

The 19 obese adolescent boys (Tanner stage 3–4) were of a mean

age of 14.5 ± 0.8 years. The participants’ characteristics are

presented in Table 1.

The mean EX duration was 44 ± 5 min. The mean heart rate was

significantly higher during EX (138 ± 5 bpm) compared with the

other conditions, and signi

ficantly higher during AVG (119 ± 1

bpm) compared with PVG (82 ± 7 bpm) and CON (71 ± 1 bpm) and

during PVG compared with CON (P

o0.001). Although mean

energy expenditure was not signi

ficantly different between AVG

(370 ± 4 kcal) and EX (358 ± 3 kcal), both were signi

ficantly higher

than during PVG (125 ± 7 kcal) and CON (98 ± 5 kcal), and energy

expenditure during PVG was higher than during CON (P

o0.001).

An overall 84% of adolescents found the AVG session to be

more dif

ficult than EX and the rate of perceived exertion was

signi

ficantly higher during EX (6.5 ± 1.2) compared with AVG

(4.5 ± 1.2) (P

o0.05).

As shown in Table 2, ad libitum energy intake at lunch time was

not signi

ficantly different between CON (1174 ± 282 kcal), PVG

(1124 ± 281 kcal), AVG (1098 ± 265 kcal) and EX (1091 ± 290 kcal).

There was no signi

ficant difference regarding the energy derived

from each macronutrient as presented in Table 2.

None of the appetite sensations explored (hunger, satiety and

prospective food consumption) were found to be significantly

different between the four experimental conditions.

DISCUSSION

Although some compensatory hypotheses have been suggested

previously, there is today no evidence regarding the energy intake

responses to video games (active and passive) in obese

adolescents. The present study is the

first to explore the energy

intake, food preferences and appetite responses to such activities,

and to compare these responses with those induced by EX in this

population. According to our results, playing active or PVGs for an

hour does not affect subsequent energy intake in 12–15-year-old

obese males compare with a control session. Interestingly,

completing a cycling EX or playing an AVG eliciting the same

energy expenditure has similar effect on energy intake, food

preferences and appetite sensations in this population.

These results are in contradiction to previously published ones

in lean adolescents showing increased

_{or decreased}

_food

consumption after playing a PVG compared with a control session,

suggesting a potential role of weight status in the control of

energy intake. Importantly, it has to be noticed that during the

present protocol the adolescents were not allowed to eat during

the activities and had to wait for the ad libitum test meal offered

about half an hour later. This might explain the lack of signi

ficance

between conditions, as ~ 50% of children and adolescents report

eating while playing computer or video games and 90% during

screen time.

_{Moreover, Lyons and collaborators found in adults a}

slightly lower energy intake during a motion-controlled video

game compared with a passive one and a control session.

_The

choice of refraining participants from eating while playing video

games in the present study was to ensure a better control of their

food consumption and also because they had to wear a portable

indirect calorimeter during AVG.

Although the statistical analysis missed revealing any signi

ficant

difference between conditions, we can observe a slight reduction

of about 85 kcal after AVG and EX compared with the control

session. Despite this lack of statistical signi

ficance, such a decrease

in spontaneous energy consumption could be of clinical

importance as it has been estimated that an energy gap of about

100 kcal/day could prevent weight gain in most of the

population.

Although the actual literature has underlined an

anorexigenic effect of acute EX in obese adolescents,

this has

been observed after intensive EXs (

470% VO

max), whereas in

the present work the EX was set at moderate intensity. Moreover,

this anorexigenic effect of exercise was mainly observed at dinner

time,

whereas only the lunch meal was assessed in the

present work.

Although the evidence remains quite limited regarding

macro-nutrient intake after sedentary activities and EX, our results

support those of others who did not

find any fat, protein or

carbohydrate intake modi

fications after a session of PVGs,

sitting

periods

or EX bouts

in lean and obese children and

adolescents. Similarly, none of the sensations of appetite (hunger,

satiety and prospective food consumption) under study differed

between conditions, which is in agreement with most of the

current literature.

Importantly, the similar energy intake

observed between conditions cannot be attributed to the lack of

differences in appetite sensations as effective food intake and

sensations of appetite were found to be unrelated in lean and

obese youth.

Table 2. Total energy intake and energy derived from the macronutrients during the experimental conditions

CON PVG AVG EX Mean s.d. Mean s.d. Mean s.d. Mean s.d. Energy intake (kcal) 1174 282 1124 281 1098 265 1091 290 Protein (%) 29.9 6.7 28.6 5.1 28.4 5.6 30.6 6.1 Fat (%) 16.6 3.8 16.1 3.9 16.2 3.7 16.7 3.8 CHO (%) 52 10.7 54.6 8.5 54.7 8.7 52.2 9.5 Abbreviations: AVG, active video game; CHO, carbohydrates; CON, control condition; EX, exercise; PVG, passive video game.

Given that the present study is the

first to consider energy

intake adaptations post video games in obese adolescents,

replication studies will be needed to confirm our findings.

However, if con

firmed, this would suggest that the previously

observed lack of weight loss after AVG-based programs in obese

adolescents

_{might be mainly due to spontaneous physical}

activity compensation and would give more credit to the actually

debated

‘activitystat’ hypothesis.

The present work only

explored the acute nutritional responses to such activities, and

longitudinal trials are needed. Another limitation of the present

work is that only boxing games were used; other activities might

have induced different acute psychological stress that has been

associated with eating in the absence of hunger.

As others

obtained contradictory results in lean adolescents after a PVG

session

and as some authors showed different energy intake

responses to acute EX between lean and obese adolescents,

it

would be necessary to conduct a similar study with both lean and

obese adolescents to further investigate the role of weight status.

From a clinical point of view, these results may suggest that the

promotion of physical EX is preferable over active video games for

bringing about an effect in an obese adolescent's energy balance.

Indeed, for the same amount of energy expended, only 44 min of

moderate intensity EX is needed where an hour of AVG is required,

without any difference in terms of energy intake compensation.

This is especially supported by the fact that an hour of

low-to-moderate EX would generate a higher energy expenditure than an

hour of AVG without increasing subsequent food consumption in

obese adolescents.

Collectively, the present results suggest for the

first time that

energy intake and food preferences after an hour of active or PVGs

remain unchanged and that isoenergetic sessions of AVGs and EX

at moderate intensity induce similar nutritional responses in obese

adolescent boys.

CONFLICT OF INTEREST

ACKNOWLEDGEMENTS

This study was supported by the 2012 DANONE Institute Research Award. The 2012 Danone Institute Research Grant funded this work.

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