Rev Bras Fisiol Exerc 2021;20(2):224-34
doi: 10.33233/rbfex.v20i2.4343
ORIGINAL ARTICLE
Metabolic responses during practice of exergames in
adults according to sex
Respostas
metabólicas durante a prática de exergames em adultos
de acordo com o sexo
Moane
Marchesan Krug1, Aline Rodrigues Barbosa2
1Universidade Regional do Noroeste do
Estado do Rio Grande do Sul (UNIJUÍ), Santa Rosa, RS, Brazil
2Universidade Federal de Santa Catarina
(UFSC), Florianópolis, SC, Brazil
Received: August 14, 2020; Accepted: February 17,
2021.
Correspondence: Moane Marchesan, Avenida Santa
Cruz 169, 404/6, 98789-150 Santa Rosa RS. mkrug@unijui.edu.br
Moane Marchesan Krug: moane.krug@unijui.edu.br
Aline Rodrigues Barbosa: aline.r.barbosa@ufsc.br
Abstract
Objective: To analyze the metabolic
responses occurring during the practice of exergames in terms of energy
expenditure, oxygen consumption rate, metabolic equivalent and heart rate in
adult men and women. Methods: The present study sample was comprised of
102 adults (52 males). Energy expenditure, oxygen consumption rate and
metabolic equivalent were assessed with a portable gas analyzer (K4b2). Heart
rate was measured with a frequency meter. All dependent variables were assessed
at rest and during the exergame session, which was comprised of four X-box 360
games (volleyball, boxing, athletics, and bowling). Results: Mean age
was 34.8 ± 13.4 years. There was a significant increase in resting values
during exergame sessions for energy expenditure (male: 467.52%; p < 0.001;
female: 393.72%; p < 0.001), oxygen consumption rate (male: 453.97%; p <
0.01; female: 384.74%; p < 0.001), metabolic equivalent (male: 457.40%; p
< 0.001; female: 384.74%; p < 0.001) and heart rate (male: 95.10%; p <
0.001; female: 92.26; p < 0.001). When compared to women, men showed
significantly higher values for energy expenditure (95% confidence interval =
-12.53; -6.67), oxygen consumption rate (95% confidence interval = -4.01;
-0.80) and metabolic equivalent (95% confidence interval = -1.18; 0.27) during
exergames. Conclusion: A session of exergames is capable of increasing
energy expenditure, oxygen consumption rate, metabolic equivalent and heart
rate in adults. Men showed higher values in metabolic parameters when compared
to women.
Keywords: energy metabolism, video games,
heart rate.
Resumo
Objetivo: Analisar as respostas metabólicas
ocorridas durante a prática de exergames em termos de
gasto energético, taxa de consumo de oxigênio, equivalente metabólico e
frequência cardíaca em homens e mulheres adultos. Métodos: A amostra do
presente estudo foi composta por 102 adultos (52 homens). O gasto energético, a
taxa de consumo de oxigênio e o equivalente metabólico foram avaliados com um
analisador de gases portátil (K4b2). A frequência cardíaca foi medida com um
frequencímetro. Todas as variáveis dependentes foram avaliadas em repouso e
durante a sessão de exergame, que foi composta por
quatro jogos no console X-box 360 (voleibol, boxe,
atletismo e boliche). Resultados: A média de idade foi de 34,8 ± 13,4
anos. Houve um aumento significativo nos valores de repouso durante as sessões
de exergame para gasto de energia (masculino:
467,52%; p < 0,001; feminino: 393,72%; p < 0,001), taxa de consumo de
oxigênio (masculino: 453,97%; p < 0,01; feminino: 384,74 %; p < 0,001),
equivalente metabólico (masculino: 457,40%; p < 0,001; feminino: 384,74%; p
< 0,001) e frequência cardíaca (masculino: 95,10%; p < 0,001; feminino:
92,26; p < 0,001). Quando comparados às mulheres, os homens apresentaram
valores significativamente maiores para gasto energético (intervalo de
confiança de 95% = -12,53; -6,67), taxa de consumo de oxigênio (intervalo de
confiança de 95% = -4,01; -0,80) e equivalente metabólico (95% de confiança
intervalo = -1,18; 0,27) durante exergames. Conclusão:
Uma sessão de exergames é capaz de aumentar o gasto
energético, a taxa de consumo de oxigênio, o equivalente metabólico e a
frequência cardíaca em adultos. Os homens apresentaram valores mais elevados
nos parâmetros metabólicos quando comparados às mulheres.
Palavras-chave: metabolismo energético, jogos de
vídeo, frequência cardíaca.
Electronic games
stand out worldwide among innovations in home technology in recent decades as
they attract children, adolescents, and adults [1]. These technologies are used
as entertainment because they provide amusement and allow a sensation of
well-being for users [2,3]. On the other hand, they also promote low physical
activity levels, which can have a repercussion on the onset of non-communicable
chronic diseases [4].
In the last
decade, a new type of videogame known as exergames appeared in the world of
technology and raised the interest of the scientific community [5]. In this
type of videogame, players need to perform body movements to control and reach
its goal [6,7].
Several studies
[8,9] showed that these body movements cause an increase in energy expenditure
(EE) [10,11], oxygen consumption rate (VO2/kg) [11,12] metabolic equivalent
(METs) and heart rate (HR) [12].
However, most
studies with exergames have been performed with children and adolescents [1,13]
or with individuals in rehabilitation [14,15,16]. Few studies have investigated
adults and taken into consideration the differences between sex and VO2/kg,
METs and HR [6,17].
Thus, the
present study aimed to analyze the metabolic responses occurring during the
practice of exergames for EE, VO2/kg, METs and HR in both sexes.
This was a
cross-sectional, descriptive, and correlational study was performed. The sample
was non-probabilistic and included 102 Brazilian adults. The inclusion criteria
were as follows: to be a member of a public university community of Southern
Brazil (students, employees, professors, and extension project participants);
and to be aged ≥ 21 years. In contrast, the following individuals were
excluded: those who used beta-blockers; those with thyroid disorders or
orthopedic injuries, those who were mobility challenged; and those who had
visual or hearing impairments which could affect the understanding of exergame
instructions.
Participants
were recruited through invitations aimed at the target population. E-mails were
sent to the coordination offices of the courses held at the Universidade
Federal de Santa Catarina and individually to the addresses registered with
the service of this university. Additionally, this project was promoted on
social media and the university website, as well as through visits to extension
projects and classrooms.
The study
protocol was approved by the Research Ethics Committee of the Universidade Federal de Santa Catarina (CAAE
32996914.0.0000.0121).
Study variables
Age (in years)
and sex (female and male) were collected through a questionnaire. Body mass
index (BMI = kg/m2) was determined by assessing body weight and
height. Body weight (kg) was measured with a scale (Toledo®; 100 g accuracy).
During measurement, individuals remained barefoot and wearing light clothing.
Height (in
meters) was determined with the use of a stadiometer (Sanny®;
0.5 cm accuracy). During measurement, participants were barefoot, standing in a
straight position, with their feet together and heels, buttocks and head
touching the stadiometer.
Muscle mass
index (MMI) was assessed with the calculation proposed by Lee et al. [18]: MMI
= height (in meters) x (0.244 x body weight) + (7.8 x height) + (6.6 x sex)
(0.098 x age) + (ethnicity – 3.3). The values attributed to sex and ethnicity
were as follows: male = 1; female = 0; Asian = 1.2; African descendant = 1.4;
Caucasian = 0.
The assessment
of EE, VO2 and MET were performed at rest and the practice of
exergames through indirect calorimetry, using a COSMED portable gas analyzer,
K4b2 model. During rest, participants were sitting in silence for ten minutes.
During exergames, the metabolic variables were assessed per game, which lasted
ten minutes each for the stabilization of physiological variables at rest.
The K4b2 system
was calibrated before each test to guarantee the exact measures of the
surrounding air, cylinder gas, turbine, and delay, according to the
manufacturer’s recommendations (COSMED SRL).
EE (kcal.min-1
METs were used
as they were multiples of resting metabolic rates [19]. They were calculated as
follows: VO2 of activity (ml(kg.min)-1)/VO2
at rest (ml(kg.min)-1).
HR was measured
with a frequencymeter (Polar®, 610i model) and it was
reported as heartbeats/minute. The maximum HR (HRmax) was found through the
calculation proposed by Karvonen, Kentala and Mustala [20].
Exergame protocol
The exergame
session was performed using the XBox360 with Kinecttm.
A 4x4 m2 area was reserved for the Kinect sensor camera to monitor
participants’ movements during games. Games were performed individually and
before the beginning of a session, interviewers provided a verbal explanation
and showed how to play each game, seeking to facilitate participants’
performance.
Kinect Sports
(1st and 2nd seasons) was used, including boxing, bowling, volleyball, and
athletics, and each game lasted ten minutes. The sequence of games was randomly
selected for each player and the first five minutes were disregarded to allow
for the stabilization of metabolic parameters. Resting periods were included
between game categories when players remained sitting and rested for five
minutes.
The practice of
exergame, the interviews, as well as the measurements of the physiological
variables (GE, VO2, METs and HR), during rest and games, were
carried out in a previously prepared room.
Data were
collected in a single session in the facilities of the Sports Center of the
Federal University of Santa Catarina (CDS/EFSC). The practice of exergames,
interviews and measurements of physiological variables (EE, VO2,
METs and HR) at rest and games were performed in a previously prepared
classroom. Anthropometric measurements (body weight and height) were taken in
the Laboratory of Physiology.
Statistical procedures
Means and
standard deviations were calculated for EE, VO2, METs and HR, according
to sex. Aiming to compare the EE, VO2, METs and HR parameters
between women and men, Student’s t test for independent samples was used.
Variance
analysis (ANOVA) for repeated measurements and pos-hoc multiple comparison
(Tukey) were applied to compare the means of EE, VO2, METs and HR
during rest and each exergame (boxing, athletics, volleyball, and bowling).
A statistical
significance level of 5% was defined for all analyses and STATA (Stata
Corporation, College Station, USA) 13.0® was used.
Table I shows
the sample characteristics. There were significant differences between men and
women for anthropometric characteristics and higher values were found for
males.
Table
I - Sample characteristics. Florianópolis, Santa Catarina, Brazil, 2014
SD =
Standard deviation; kg = kilogram; m = meters; BMI = body mass index; IMM =
muscle mass index
According to
Table II, there was a significant increase (p < 0.001) in EE, VO2/kg,
METs and HR values during the four games for both sexes. Comparisons between
exergame categories showed significant differences in VO2/kg and
METs for bowling and boxing, indicating statistically higher values during
boxing practice.
Table II - Means and standard deviations
for EE (kcal/min)-1, VO2 ml(kg.min)-1,
METs and HR (bpm), in different games according to sex. Florianópolis,
Santa Catarina, Brazil, 2014 (n = 102)
abcd
= Means followed by letters may show differences between them; p-value <
0,001
Boxing was the
most intense game for both men and women, reaching the highest EE, VO2/kg,
METs and HR values. Bowling was the least intense game for both sexes,
according to the values found for EE (7.31 ± 2.52 kcal min-1), VO2/kg
(20.18 ± 5.67 mL kg-1 min-1) and METs (5.83 ± 1.56),
while HR (141.38 ± 22.94 bpm) was the least intense for women exclusively.
Among men, the lowest mean values of HR were found for volleyball (129.78 ±
21.06 bpm). These data are shown in Table II.
Additionally,
the percentage area of HRmax reached during the practice of exergames was
higher than 70% for both women and men. Boxing was the game that showed the
highest values, 78% and 76% of the HRmax for males and females respectively
(Table II).
Tables III and
IV show the comparison between metabolic parameters, measured during rest and
game session for males and females, respectively. There was a significant
increase in resting values during the game session for EE (male: 467.52%; p
< 0.001; female: 393.72%; p < 0.001), VO2/kg (male: 453.97%; p
< 0.01; female: 384.74%; p < 0.001), METs (male: 457.0%; p < 0.001;
female: 384.74%; p < 0.001) and HR (male: 95.10%; p < 0.001; female:
92.26; p < 0.001). The effect size was high for all variables (d ≥
0.80).
Table III - Comparison of metabolic
parameters measured during rest and exergames: data for men. Florianópolis, Santa Catarina, Brazil, 2014 (n = 52)
SD = standard
deviation; CI = confidence interval; EE = energy expenditure; VO2 =
oxygen consumption; METs = metabolic equivalent; HR = heart rate; bpm = beats
per minute; % = percentage; ES = effect size
Table IV - Comparison of metabolic
parameters measured during rest and exergames: data for women. Florianópolis, Santa Catarina, Brazil, 2014 (n = 50)
SD = standard
deviation; CI = confidence interval; EE = energy expenditure; VO2 =
oxygen consumption; METs = metabolic equivalent; HR = heart rate; bpm = beats
per minute; % = percentage; ES = effect size
Figure 1 shows
the comparisons between sexes during rest and practice of exergames. EE showed
a significant difference during rest (95%CI = -0.043; -0.09) and games (95%CI =
-12.53; -6.67) between men and women, indicating higher values for males. In
resting conditions, there were no differences between sexes for VO2/kg
and METs. During the session of exergames, men showed significantly higher
values compared to women in VO2/kg (95%CI = -4.01; -0.80) and METs
(95%CI = -1.18; 0.27). Women showed higher HR values than men did at rest
(95%CI = 1.85; 13.1).
Energy expenditure
according to condition and sex – rest/exergames – men/women
Heart rate according to
condition and sex – beats per minute – rest/exergames – men/women
Oxygen consumption rate
according to condition and sex – rest/exergames – men/women
Metabolic equivalent of
task according to condition and sex – rest/exergames – men/women
Figure 1 - Energy expenditure, oxygen
consumption rate, metabolic equivalent of task and heart rate at rest and
during the exergame session: comparison between sex performed with Student’s
t-test for independent samples
The results
showed that the practice or exergames increase EE, VO2/kg, METs and
HR values, when compared to resting conditions. Among the games performed,
boxing was the one that enabled the highest increase in such parameters in both
sexes.
The increase in
metabolic parameters in response to the practice of exergames has been found by
other authors [9,21,22,23] and it can be explained by the increase in the
metabolic demands of muscles activated when body movements are performed [23].
In the present
study, EE increased approximately 460% during exergames, compared to the
resting condition. This significant increase was like that found by Siegel et
al. [9] in a study performed with young adults and higher than those of other
studies conducted with adults [21,22,23]. The differences between studies can be
explained by the characteristics of each sample, in addition to the game type
and duration. In the study performed by Lyons et al. [24], apart from
participants’ mean age being lower than that of the present study, the
exergames selected were as follows: Dance Dance
Revolution (dance), Medal Honor and Resident Evil (shooting), Guitar Hero and
Rock Band (bands) and Wii Fit (physical activities).
VO2/kg
increased significantly during the practice of exergames, when compared to the
resting period. Other authors [21,22,24,25] also reported an increase in this
parameter in response to the practice of exergames, although on a lower level.
The differences
in VO2/kg pointed out between studies can be explained by the
participant characteristics [26]. In the study conducted by Noah et al.
[21], most participants were female, a factor that influenced the lower VO2/kg
values. On the other hand, the study conducted with young adult males showed
greater increases in VO2/kg during the practice of X-box [27], when
compared to the results of the present study.
Sex explains the
difference in values found in the studies, as males showed higher VO2/kg
values when compared to females [28], mainly due to men’s greater muscle mass
[29].
The results
showed an increase in the estimates of MET values during exergames, compared to
resting values, as observed by other authors [8,9]. However, data from the
present study were higher than those found in other studies with adults [9,30]
and elderly individuals [31].
The differences
found between studies regarding MET values obtained during exergames [9,31,32]
were probably influenced by the characteristics of samples (sex, age,
ethnicity, and body composition). In the study performed by Taylor et al.
[31], the sample included elderly individuals, which probably explains the
lower MET values found, when compared to those of the present study. Another
factor that could have influenced these differences is the type of game and its
duration. When investigating adults, O’Donavan et
al. [30] found lower MET values than those found in the present study. Such
differences could have occurred due to the game duration, which was shorter in
the present study.
Although not
being the objective of the present study, it should be emphasized that,
according to the recommendations from the American College of Sports Medicine
[33], exergame categories can be classified as moderate (bowling) and vigorous
(boxing, volleyball, and athletics).
The results
showed an increase in HR during the practice of exergames, when compared to
resting values, as observed in other studies [5,6,9,22]. The increase in HR is
the result of autonomous and hemodynamic adaptations that influence the
cardiovascular system [4,34,35].
Other studies
have reported significant increases in HR during the practice of exergames that
were lower than those found in the present study [9,36]. One such study was
that conducted by O’Donavan and Hussey [22], which
showed a significant increase of 86% in HR during the practice of boxing with
Nintendo Wii, with resting values used as reference.
In the present
study, boxing was the exergame category that led to the highest EE, VO2/kg,
METs and HR values. In this game, all body parts are used, although there is a
predominance of the upper limbs. Players move constantly and the pauses during
this game are shorter than those of other categories (volleyball, athletics,
and bowling).
Maddison et
al. [37] explain that exergames using all body parts show higher energy
expenditure, when compared to those involving the upper limbs exclusively.
Graves, Ridgers and Stratton [38] found higher EE values
in games including the upper limbs, when compared to the entire body.
Although bowling
includes the upper limbs, this was the least intense game in the present study.
However, differently from boxing, bowling does not involve a virtual opponent due
to the precision of movements and players perform tasks at a slower speed.
The comparisons
between sexes point to higher EE, VO2/kg and METs values for men
when compared to women during the practice of exergames. The differences
between sexes can be explained by the higher MMI found in males, compared to
females. The more muscle mass, the more contractions are performed and the
higher the effort rate [28].
Differences
between sexes for EE, VO2/kg, METs and HR during the practice of
exergames are controversial. Some authors point out that, during the practice
of exergames, EE values are higher for males [39], while others did not find
differences between women and men [17], although differences in some types of
game were reported [38].
The present
study showed limitations and strong points that should be emphasized. One of
the limitations refers to the intentional sample, as it does not enable data
from the present study to be extrapolated to other populations. Moreover,
although the time set for each game was equal for all participants, individual
motor skills could have interfered with this time.
One of the
strong points was the technique used for data collection (indirect
calorimetry), which enabled accurate and reliable results. Additionally,
another point that stood out was participants’ age. Most of the studies
published to date have been with children, adolescents, and the elderly, with a
gap on the behavior of metabolic parameters during the practice of exergames in
adults. Finally, the sample size must be reported as a positive point, in view
of the quantity if analyzed subjects.
According to the
data obtained in the present study, the practice of exergames could promote a
relevant increase in EE, VO2/kg, METs, and HR values, when compared
to the resting period, in adults of both sexes. Comparisons between sexes
showed higher EE, VO2/kg, METs values for men, when compared to
women, except for HR, which did not show differences between sexes. Thus, such
practices could be improved and used to promote population health through an
increase in physical activity level. Finally, new studies on the implications
of a session of exergames on EE, VO2/kg, METs, and HR of men and
women must be performed, aiming to reduce the inconsistencies found in the
literature.
Conflict of interest
No conflicts of
interest have been reported for this article.
Financing source
This study was financed
in part by the Coordination for the Improvement of Higher Education
Personnel - Brazil (CAPES) - Code Funding 001.
Authors´s contributions
Conception and design
of the research: Krug MM, Barbosa AR; Data collection: Krug MM;
Analysis and interpretation of data: Krug MM; Statistical
analysis: Krug MM; Writing of the manuscript: Krug MM, Barbosa AR;
Critical revision of the manuscript for important intellectual
content: Krug MM, Barbosa AR.