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The stress of chess players as a model to study the effects of psychological stimuli on physiological responses: An example of substrate oxidation and heart rate variability in man

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We have studied the physiological consequences of the tension caused by playing chess in 20 male chess players, by following heart rate, heart rate variability, and respiratory variables. We observed significant increase in the heart rate (75-86 beats/min), in the ratio low frequency (LF)/high frequency (HF) of heart rate variability (1.3-3.0) and also a decrease in mean heart rate variability with no changes in HF throughout the game. These results suggest a stimulation of the sympathetic nervous system with no changes in the parasympathetic system. The respiratory exchange ratio was rather elevated (over 0.89) at the start and significantly decreased during the game (0.75 at the end), indicating that energy expenditure progressively switched from carbohydrate to lipid oxidation. The changes in substrate oxidation and the sympathetic system seem to be due to high cognitive demands and bring new insight into adaptations to mental strain.
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The stress of chess players as a model to study the effects
of psychological stimuli on physiological responses: an example
of substrate oxidation and heart rate variability in man
Nicolas Troubat ÆMarie-Agnes Fargeas-Gluck Æ
Mikko Tulppo ÆBenoit Dugue
Accepted: 15 October 2008 / Published online: 6 November 2008
ÓSpringer-Verlag 2008
Abstract We have studied the physiological conse-
quences of the tension caused by playing chess in 20 male
chess players, by following heart rate, heart rate variability,
and respiratory variables. We observed significant increase
in the heart rate (75–86 beats/min), in the ratio low fre-
quency (LF)/high frequency (HF) of heart rate variability
(1.3–3.0) and also a decrease in mean heart rate variability
with no changes in HF throughout the game. These results
suggest a stimulation of the sympathetic nervous system
with no changes in the parasympathetic system. The
respiratory exchange ratio was rather elevated (over 0.89)
at the start and significantly decreased during the game
(0.75 at the end), indicating that energy expenditure pro-
gressively switched from carbohydrate to lipid oxidation.
The changes in substrate oxidation and the sympathetic
system seem to be due to high cognitive demands and bring
new insight into adaptations to mental strain.
Keywords Chess Heart rate variability
Indirect calorimetry Psychological crossover concept
Psychological stress Substrate oxidation
Traditionally, the effects of psychological stress in man
have been investigated using two different kinds of situa-
tions: laboratory experiments and real-life stressors.
Laboratory tests (e.g. speech tasks, arithmetic tasks, Stroop
test, etc.) consist of a stimulus of short duration and of
limited potency. Investigations using real-life stressors can
be divided into those using chronic stressors (e.g.
bereavement, unemployment, divorce, caring for patients
with Alzheimer’s disease, etc.) and acute stressors (e.g.
academic exams). One advantage of using arranged stress
situations (laboratory tests and real-life stressors) is that
one can easily use each individual as his or her own con-
trol. However, because of ethical and legal considerations,
it is difficult to experimentally induce pure psychological
stress. Also, it is difficult to avoid unnatural and artificial
arrangements (Dugue
´et al. 1992,2001).
Stress is often defined as a threat (real or implied) to
homeostasis (McEwen and Wingfield 2003) and is known
to stimulate the autonomic nervous system, which in turn
stimulates the cardiovascular system and the metabolism.
Mental effort induces the mobilization of energy for cog-
nitive purposes and induces a compensatory strategy to
protect performance in the presence of augmented request
tasks and psychological stressors (Gaillard 1993,2001).
Though it is well known that glucose is used as a primary
fuel for energy generation in the brain during psychological
stress or mental effort (Rao et al. 2006; Fairclough and
Houston 2004; Sourkes 2006), very little information is
available concerning the global metabolism of substrates
during mental strain. This lack of exploration may be the
result of drawbacks to the available techniques that disturb
the subject during investigation, of difficulties in applying
these techniques, and of continuously monitoring subjects
N. Troubat M.-A. Fargeas-Gluck B. Dugue
UFR Sciences du Sport de l’Universite
´de Poitiers et Laboratoire
des Adaptations, Physiologiques aux Activite
´s Physiques
(EA 3813), 4 alle
´e Jean Monnet, 86000 Poitiers, France
M.-A. Fargeas-Gluck
Department of Sport Sciences,
University of Limoges, Limoges, France
M. Tulppo
Department of Physical Rehabilitation, Verve, Oulu, Finland
Eur J Appl Physiol (2009) 105:343–349
DOI 10.1007/s00421-008-0908-2
through a mental challenge. However, with the develop-
ment of new generation of portable metabolic systems, it is
now possible to monitor cardio-respiratory variables during
a challenging situation with only minor disturbances.
A chess game represents a legitimate psychological
stress. It is a strategic and high cognitive demand task.
Players have to think through a wide range of move
sequences to find the best choice. This very challenging
and interesting situation has not been thoroughly explored,
and to date, most of the reports have concentrated on
psychological measurements and not on physiological
outcomes. The only available study in that field was the
one of Schwarz et al. (2003).
Accordingly, we studied the effect of the tension caused
by playing a chess game on heart rate, heart rate variability,
and respiratory variables. Using indirect calorimetry, we
deduced the oxidation rate of lipids and carbohydrates and
also total energy expenditure during the challenge. More-
over, we investigated the influences of the expertise of the
players on the physiological responses in this atypical
Subjects and methods
A total of 20 male chess competitors of national and
international level (age: 42 ±13 years; height: 178 ±
4 cm; weight: 76 ±9 kg; BMI: 24 ±3kgm
) partici-
pated in our study. They were subjectively healthy, and
none were on medication. The experiment was conducted
in accordance with the Declaration of Helsinki, and all the
procedures were carried out with written informed consent
of the participants. Volunteers were classified according
their ELO score (official rating of the International Chess
Association). The group of our subjects had an ELO (mean
and extreme values) of 1,757 (1,250–2,170).
Study design
The experiment started with the lunch (standardized) of the
participants, which was taken between 12.00 and 13.00.
Then at 16.30, the participants started their chess session.
Before the start of the experiment, instructions were given
to the participants about the procedures and protocol
requirements during the test. In order to make the partici-
pants comfortable, they were asked to relax in a supine
position for 15 min. Moreover, all participants underwent a
familiarization period with the equipment required for
testing. The experimental room was calm (no more than 2
observers and the player) and light and temperature (18°C)
were continuously regulated.
Chess game
The participants played a chess game against a computer
with software that mimed a level of expertise which was
similar to the player’s level (Chessmaster 9th edition,
2004). This software was used because of the ability to
select a wide range of ELO levels. In fact, without telling
the participants, we set the program at a slightly higher
level (?100 ELO points) than the level of the player. A
laboratory assistant who was familiar with chess was
always present during experiments. He performed the
moves indicated by the computer on the chess board, and
he also served as the human presence in front of the par-
ticipants. One hour was allotted for each player (an
electronic clock was used to control the time). Cardio-
respiratory variables were continuously recorded until the
chess game were over (approximately 90 min, the com-
puter also needed some time before indicating its move).
Psychological measurements
This test presents 20 adjectives, 10 that assess positive
affectivity (e.g., excited) and 10 that assess negative
affectivity (e.g., upset) (Watson et al. 1988). These adjec-
tives describe different feelings and emotions. Participants
described their present feelings on a five point scale,
ranging from ‘‘very slightly’’ (1) to ‘‘extremely’’ (5).
Brief COPE (dispositional version of trait anxiety)
This test is the abridged version of the COPE inventory
(Carver et al. 1989) and presents 14 scales that assess dif-
ferent coping dimensions: active coping, planning, using
instrumental support, using emotional support, venting,
behavioral disengagement, self-distraction, self-blame,
positive reframing, humor, denial, acceptance, religion, and
substance use. Each seven point scale, ranging from ‘‘never’
(1) to ‘‘always’’ (7), contains two items (28 items altogether).
Both questionnaires were presented before the start of
the experiment.
Physiological measurements
A portable metabolic measurement system (Vmax ST;
Sensor Medics, Germany) and a heart rate monitor (Polar
S810, Finland) were used to measure the cardio-respiratory
responses and heart rate variability. The gas analyzer sys-
tem was calibrated before each subject session using gases
of known concentrations and used thereafter as previously
described (Brehm et al. 2004; Laurent et al. 2008). The
following variables were recorded throughout the game:
344 Eur J Appl Physiol (2009) 105:343–349
heart rate (HR), ventilatory flow (VF), tidal volume (Vt),
breath frequency (bF), O
consumption ð_
duction ð_
VCO2Þ;respiratory exchange ratio (RER), and the
following indices were analyzed after the test: mean R–R,
low frequency (LF), high frequency (HF)—an index of the
activity of the parasympathetic branch of the autonomic
nervous system, LF/HF ratio (LF/HF)—an index of the
activity of the sympathetic branch of the autonomic ner-
vous system, carbohydrate oxidation rate (CHO), lipid
oxidation rate (FAT), and energy expenditure (EE). The
baseline measurements were carried out before the begin-
ning of the match in sitting posture during 3 min.
Data processing
The R–R intervals were recorded (Polar S810, Finland) at a
frequency of 1,000 Hz (Ruha et al. 1997) and saved in a
computer for further analysis of HR variability from the R–
R interval tachogram with Heart Signal software (Kempele,
Finland). All the R–R intervals were edited by visual
inspection, to exclude all the undesirable beats, which
accounted for \1% in every subject. The details of this
analysis and the filtering technique have been described
previously (Huikuri et al. 1992,1996). The mean R–R and
the standard deviation of all R–R intervals were used as
time domain analysis methods. An autoregressive model
(model order 20) was used to estimate the power spectrum
densities of heart rate variability. The power spectra were
quantified by measuring the area under the whole fre-
quency band (total power) and under two frequency bands:
LF power, from 0.04 to 0.15 Hz; and high-frequency
power (HF), from 0.15 to 0.4 Hz. We also calculated LF
and HF in normalized units (n.u) with the same algorithm.
Series of 300 s or approximately 256 consecutive R–R
intervals (which is a minimal time requirement) were
extracted 5 min before the game, at the beginning, at the
middle, and at the end of each game. The same periods were
analyzed for respiratory measurements. Indirect calorimetry
was used to calculate the carbohydrate (CHO) and lipid
oxidation (FAT), and total energy expenditure during the
match. We used stoichiometric equations and appropriate
caloric equivalents (Peronnet and Massicotte 1991), with the
assumption that the nitrogen excretion rate was 135 lg
(Romijn et al. 1993). The equations were:
CHO rate oxidation (g min1Þ
¼ð4:585 _
VCO2Þð3:226 _
Fat rate oxidation (g min1Þ¼ð1:695 _
ð1:701 _
Mass was expressed in grams per minute and gas
volume in liters per minute. _
VO2and _
VCO2values were
averaged every minute.
Total energy expenditure ¼½ð%CHO=100Þ _
5:05 kcal L1
þ½ð%Fat=100Þ _
4:7 kcal L1
The percentages of carbohydrates and lipid oxidations
were calculated by using the following equations:
%CHO ¼½ðRER 0:71Þ=0:29100
%Fat ¼½ð1RERÞ=0:29100:
All the statistical analyses were completed using Statistica
5.5 software. Results are presented as their mean ±SD or
extreme values. ANOVA for repeated measurements and
Tukey post hoc tests were used to analyze the data.
Spearman correlation test was also used. Significance was
set at P\0.05.
The PANAS gave a positive affect of 3.2 (2.3–4.3) and a
negative affect of 1.3 (1–1.8). The brief COPE showed an
active coping score of 3 (1–4), planning of 2.9 (1–4),
positive reframing of 2.8 (1.5–3.5), acceptance of 2.7
(1–4), self-distraction of 2.6 (1–4), using instrumental
support of 2.4 (1–4), middle level of humor of 2.2 (1–4),
using emotional support of 2.2 (1–4), self-blame of 2.1
(1.5–3), venting of 2 (1–3), low level of behavioral
disengagement of 1.3 (1–2.5), denial of 1.3 (1–3.5),
substance use of 1.3 (1–3), and religion of 1.2 (1–2).
We observed a significant increase in heart rate right at
the beginning of the contest and the rate stayed elevated
until the end of the game (Fig. 1). Significant increases
both in LF and in the LF/HF ratio (Fig. 1) and a significant
decrease in the mean R–R were also observed (Table 1).
No changes in HF and HF n.u. were found. The CO
release and the respiratory exchange ratio significantly
decreased during the game (Fig. 2). When calculating the
oxidation rate, lipid oxidation was found to significantly
increase, whereas glucose oxidation significantly decreased
(Fig. 2). At the 25 min time point, the two oxidation curves
crossed each other. No significant changes were noted in
VO2;EE, VF, Vt, and bF.
In addition, no significant correlation was found
between the outcome of the PANAS and brief COPE tests
and any of the physiological variables. All participants lost
their game and reported that their level of effort was sim-
ilar to a tiring, serious match. All of the data concerning
physiological variables before and during chess play are
presented in Table 1. The overall energy expenditure in our
Eur J Appl Physiol (2009) 105:343–349 345
players during the entire game was of 138 kcal (extreme
values 102–198 kcal).
We have studied the effects of playing chess in chess
competitors (national and international level) on a series of
cardio-respiratory and metabolic variables.
The evaluation of our subjects through the PANAS and
the Brief COPE tests before the chess contest showed that
their basal amount of perceived stress was rather low and
they were psychologically healthy. Also, all of our subjects
reported that the contest was as challenging and tiring as a
regular match. Therefore, artifacts due to specific psycho-
logical state or trait do not seem to generate bias in the
stress-induced physiological responses of our subjects.
Before the beginning of the contest, the heart rate was
rather elevated. Such observations indicate that our par-
ticipants were reacting to the start of the game via
anticipatory mechanisms (Wirtz et al. 2006). At the start of
the game, both heart rate and RER slightly increased. Such
elevated levels could indicate that substrate oxidation
mainly involved carbohydrates. However, the transient
increase in RER may also reflect changes in respiratory
phenomena. Only a slight increase (not significant) in the
ventilation rate was observed at the beginning of the game.
In any case, this indicates that the players were very
reactive. Such changes are certainly under sympathetic
control, and may be related to unspecific stress responses
(Selye 1951). Many studies in humans have documented an
increase in SNS activation during mental stress (e.g. See-
matter et al. 2000; Garde et al. 2002). In fact, the heart rate
variability measurements in our participants at the begin-
ning of the game revealed a significant increase both in LF
and in the LF/HF ratio, a decrease in mean R–R and no
changes in HF, indicating an activation of the sympathetic
system (Montano et al. 1994; Pagani et al. 1991) with no
changes in the parasympathetic system (Hayano et al.
1991). It is well known that Vt and bF have a large impact
on the HRV indices, especially in the vagally mediated HF
spectral band (Hirsch and Bishop 1981). Both Vt and bF
were measured continuously during the study, and we did
not observe any significant changes in breathing pattern.
These results indicate that the changes in the spectral
component of the R–R intervals are due to increased
sympathetic stimulation rather than to changes in respira-
tion pattern or in vagal activation. During the game, we
initially observed stabilization in the heart rate, followed
by a significant increase through the end of the game.
During that time, the CO
release significantly decreased,
whereas oxygen consumption stayed stable. This led to a
significant decrease in the RER. One possible explanation
could again be hyperventilation, which could eventually
lead to a relative lowering in CO
production (hypocapnia)
related to O
consumption. However, no hyperventilation
Fig. 1 Indexes of sympathetic involvement before and during a chess
game: aHeart rate; bLF/HF ratio (number of subject =20);
*P\0.05. LF/HF Ratio between the low and high frequency band
Fig. 2 Indexes of substrate utilization before and during a chess
game: aRER; bCHO and FAT oxidation rate (%) (number of
subject =20); * P\0.05. RER Respiratory exchange ratio; CHO
carbohydrate oxidation rate; FAT lipid oxidation rate
346 Eur J Appl Physiol (2009) 105:343–349
was noticed during the course of our study. Therefore, a
significant increase in lipid oxidation and a dramatic
decrease in carbohydrate metabolism may have occurred
during the match.
At the end of the game, the oxidation of carbohydrates
was very low, and the participants were almost exclusively
oxidizing lipids. During the whole game, the total energy
expenditure remained constant, but was more elevated than
during resting time (Levine et al. 2000; Levine 2005).
However, we cannot exclude that we might have observed
a transient increase in carbohydrate consumption at the
beginning of the game and then a return to resting condi-
tion. During the game, the levels of LF and the LF/HF ratio
were elevated and were significantly higher than before the
start of the game. The HF level did not change during the
game. Therefore, the sympathetic system seems to be
stimulated during the course of the contest, with no chan-
ges in the parasympathetic system. However, it has
previously been demonstrated that brief exposure to psy-
chological stressors may lead to both an increase in LF and
in the LF/HF ratio with a reduction of the HF level,
indicating increased sympathetic activity along with with-
drawal of the parasympathetic system (e.g. Delaney and
Brodie 2000). Somehow, our results with respect to the
absence of any parasympathetic withdrawal during the
course of the game are at variance with those reported in
the literature. However, the nature of the stimulus was
different, and the mental workload might have been lower
in our study as our volunteers were well trained in handling
such stimuli. Furthermore, the interplay between the sym-
pathetic and vagal regulation of HR is not always
organized in a reciprocal fashion, wherein increased
activity in one system is accompanied by decreased activity
in the other. A simultaneous sympathetic and vagal acti-
vation has been observed during cold face immersion
(Tulppo et al. 2005), and also in other circumstances in
healthy subjects (Mourot et al. 2007). It is highly possible
that increased sympathetic activation occurs without any
change in vagal outflow during a demanding mental stress
situation without exercise or body position changes, as in
the present study.
All of our observations indicated that the chess players
were very stimulated during the game, but the nature of the
stimuli might have been different during the contest com-
pared to the stimuli that occurred before and at the
beginning of the game. Interestingly, the two oxidation
curves (lipid and carbohydrate) crossed each other 25 min
after the start of the contest. Such changes observed during
the game may reflect an adjusted response to the real
demands of the task. After the more acute response that
was observed right at the beginning of the game, the sub-
ject may have been adjusting to a longer lasting effort.
It is not clear why there could be a switch in substrate
oxidation during a lasting mental challenge. Numerous
studies have shown that different kinds of stressors
(examination, environmental stressors, and laboratory-
Table 1 Heart rate, gas and metabolic variations during the chess match in experienced chess players (n=20)
Parameters Units Before Beginning Middle End
HR beats min
75 (60–101) 81 (59–108)* 79 (65–95) 86 (65–120)*
Mean R–R ms 877 (585–1,210) 819 (666–1,022)* 779 (639–930)* 766 (556–953)*
LF ln ms
6.3 (4.2–8.0) 6.7 (5.2–8.1)* 6.8 (4.9–8.2)* 6.6 (4.0–8.2)*
HF ln ms
5.7 (3.8–7.3) 6.1 (3.6–7.3) 5.8 (3.6–7.6) 5.7 (2.1–7.4)
HF n.u 33.5 (22–44.6) 32.3 (18.9–51.5) 30.8 (13.6–44.3) 31.4 (13.1–50.2)
LF/HF 1.3 (0.2–5.1) 2.4 (0.5–5.1)* 3.3 (0.8–8.1)* 3.0 (1.0–7.0)*
Vt ml min
0.59 (0.40–0.79) 0.63 (0.44–0.82) 0.55 (0.38–0.80) 0.58 (0.43–0.80)
bF cycle min
15.99 (10.97–20.40) 15.94 (10.86–22.20) 15.94 (10.50–21.40) 16.29 (10.70–22.30)
VF l min
9.61 (6.87–13.38) 10.32 (6.62–13.55) 9.06 (5.95–13.15) 9.52 (5.59–13.30)
VO2ml min kg
4.18 (2.36–6.71) 4.51 (2.59–5.80) 4.32 (2.78–5.89) 4.41 (2.59–6.34)
VCO2ml min kg
3.57 (2.37–5.45) 3.94 (2.23–5.27) 3.04 (1.95–4.37)* 3.11 (1.72–4.65)*
RER 0.89 (0.79–1.03) 0.92 (0.81–1.07) 0.75 (0.67–0.81)* 0.74 (0.65–0.89)*
CHO g min
0.22 (0.10–0.51) 0.27 (0.11–0.74) 0.01 (0.00–0.16)* 0.002 (0.00–0.32) *
FAT g min
0.08 (0.04–0.21) 0.07 (0.02–0.15) 0.16 (0.09–0.22)* 0.16 (0.07–0.24) *
EE kcal min
1.53 (1.14–2.00) 1.67 (1.18–2.20) 1.53 (1.17–2.01) 1.55 (1.14–2.04)
Results are expressed as mean and extreme values in brackets
HR Heart rate; Mean R–R mean values of heart rate variability; LF low frequency; HF high frequency; LF/HF ratio between the low and high
frequency band; _
consumption; _
production; RER respiratory exchange ratio; bF respiratory frequency; VF ventilatory flow; Vt
tidal volume; CHO carbohydrate oxidation rate; FAT lipid oxidation rate; EE energy expenditure
*P\0.05 compared to the data obtained before the contest
Eur J Appl Physiol (2009) 105:343–349 347
based stressors) may influence metabolism and the con-
centration of lipids in blood (Stoney et al. 1997,1999;
Niaura et al. 1992). However, not much is known con-
cerning the use of substrates during mental challenge.
Interestingly, similar kinds of adaptations have been
reported in exercise physiology. Moderate physical exer-
cise is generally associated with the preponderant
utilization of lipids, whereas acute and intensive physical
exercises are under carbohydrate metabolism. The shift in
substrate oxidation has been described as the ‘‘crossover
concept’’ and depends on the relative intensity of the
exercise and therefore on the endurance training of the
subjects (Brooks and Mercier 1994). Similarly, this may
apply to psychological stress physiology. However, to
validate such a psychological crossover concept, one
should be able to quantify the intensity of psychological
stress and relate it to substrate oxidation. Another inter-
esting feature in this context is that training (endurance
training?) of the subject could influence substrate oxidation
during a mental challenge. One could therefore speculate
that specific training could be designed for chess players.
However, to validate such a new approach, further inves-
tigations are required.
In summary, we herein described an interesting real-life
stressor that seems to be a useful stress model in that it
had significant effects on heart rate variability and
Acknowledgments The study was partly supported by the Chess
League of Limousin, France. The authors are very grateful for the
volunteers who were all very excited to participate and the League of
Limousin that encouraged this research. The Conseil Ge
´ral de la
Vienne is also thanked for inspiring our collaboration with research
laboratories of the Oulu region (Finland) and for giving a traveling
grant (BD).
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... RER has been studied to determine energy expenditure in demanding situations (Troubat et al. 2008). RER is the ratio between the amount of CO2 produced in metabolism and O2 used. ...
... While higher demand are clearly marked by faster respiratory rate and higher minute ventilation, the breathing amplitude seems to remain stable also the mean inspiratory flow rate (Wientjes et al. 1998) and %RCi (Vlemincx 2010) seems to increase. Besides that, CO2 release and petCO2 significantly decreased, whereas oxygen consumption stayed stable (Grassmann et al. 2017;Troubat et al. 2008) ...
... Proceedings of the International Conference on Industrial Engineering and Operations Management Sao Paulo, Brazil, April 5 -8, 2021 Roscoe (1992) v v v Wilson (1993) v v Backs and Seljos (1994) v v v Brookings et al. (1996) v v Veltman and Gailllard (1998) v v v Wientjes et al. (1998) Fournier et al. (1999) v v Bernadi et al. (2000) v v Houtven et al. (2002) v v Veltman (2002) v v Fairclough et al. (2005) v Beda et al. (2007) v v v Schleifer et al. (2008) v v Troubat et al. (2008) v Roscoe 1992;Fournier et al. 1999;Veltman and Gailllard 1996;Veltman and Gailllard 1998;Wang et al. 2015;Fairclough et al. 2008;Bruna et al. 2018;Karavidas et al. 2010 Non spesific domain Backs and Seljos 2002;Wientjes et al. 1998;Bernadi et al. 2000;Houtven et al. 2002;Beda et al. 2007;Troubat et al. 2008;Vlemincx et al. 2010;Hogervorst et al. 2014;Kodesh and Kizony 2014;Kuehl et al. 2015;Nagasawa and Hagiwara 2016;Bruder et al. 2019 12 Wilson 1993;Grassmann et al. 2016;Backs and Seljos 1994;Brookings et al. 1996;Fournier et al. 1999;Fairclough et al. 2005;Mehler et Respiratory is a physiological process mainly related to the exchange of O2 and CO2 from body tissues to the air. Respiration is measured using two elastic belts which placed around the chest and abdomen. ...
... Whereas, Kocak [19] showed that amateur e'athletes expend 40% more energy or 1.9 METs during gameplay when compared to rest, which could be classi ed as light physical activity. Within other sedentary environments, high level chess players show no signi cant changes in VȮ 2 , energy expenditure, breathing frequency, tidal volume, or ventilatory ow, during gameplay [20]. However, the authors observed an initial increase in RER which gradually decreased during the game, indicating a shift in carbohydrate to lipid oxidation [20]. ...
... Within other sedentary environments, high level chess players show no signi cant changes in VȮ 2 , energy expenditure, breathing frequency, tidal volume, or ventilatory ow, during gameplay [20]. However, the authors observed an initial increase in RER which gradually decreased during the game, indicating a shift in carbohydrate to lipid oxidation [20]. Differences across studies may be due to differences in settings, level of expertise, various game titles, and/or different competitive settings which highlights that the physiological demands of esports are not yet fully understood. ...
... These results are supported by a non-signi cant difference in ventilation between testing conditions which highlights that the increase in RER is due to carbohydrate oxidisation and not hyperventilation. These results are different to previous studies as Zimmer et al., [18] and Troubat et al., [20] who demonstrated a signi cant time effect on RER, with signi cantly lower values in the post-phase of gaming. When converting the RER values observed within our study into a percentage of energy derived from carbohydrate oxidation, differences across conditions were 48.3% carbohydrate oxidation in the RMR to 71.9% carbohydrate oxidation in the GMR condition [37]. ...
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Background Research into esports suggests that e’athletes experience multiple physiological stressors and demands during competition and training. The physiological demands of esports are poorly understood and need to be investigated further to inform future training guidelines, optimise performance outcomes, and manage e’athlete wellbeing. The aim of this research was to quantify the metabolic rate of esports gameplay and compare this outcome with heart rate variability within expert e’athletes. Results Thirteen healthy male participants ranked within the top 10% of their game respective esports title participated within the study (age = 20.7 ± 2.69 years; BMI = 24.6 ± 5.89 kg·m− 2). Expired gas analysis indirect calorimetry measured gas exchange during rest and gaming. Compared to resting conditions, competitive esports gameplay significantly increased median energy expenditure (1.28 (IQR 1.16–1.49) kcal·min− 1 vs. 1.45 (IQR 1.20–1.77) kcal·min− 1, p = .02), oxygen consumption (0.27 (IQR 0.24–0.30) L·min− 1 vs. 0.29 (IQR 0.24–0.35) L·min− 1, p = .02) and carbon dioxide production (0.20 (IQR 0.19–0.27) L·min− 1vs. 0.27 (IQR 0.24–0.33 ) L·min− 1, p = .01). Competitive gameplay also resulted in a significant increase in heart rate (84.5 (IQR 74.1–96.1) bpm vs. 87.1 (IQR 80.3–104) bpm, p = .01) and decrease in R-R interval’s (710 (IQR 624–810) ms vs. 689 (IQR 579–747) ms, p = .02) when compared to rest. However, there was no significant differences in time or frequency measures of heart rate variability. Conclusions The data reveal there are increased physiological responses to metabolic rate, energy expenditure and cardiovascular function to esports game play within expert e’athletes. Further physiological research into the physical demands on e’athletes, the influence of different training programs to esport performance, and the added multivariate determinants to elite level esport performance are warranted.
... Our study results showed a significant increase in serum Hcy levels after 40-min aerobic running, chess, or [37]. Chess is a strategy game that requires to respond high cognitive demand tasks. ...
... An interesting finding of our study is the increased serum Hcy levels after chess exercise. According toTroubat et al. (2009), chess games are considered a mental stressor ...
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This study aimed to investigate acute effects of table tennis (physical+cognitive exercise), aerobic running (physical exercise), and chess (cognitive exercise) exercise sessions of veteran male athletes in their branches on the serum homocysteine (Hcy), insulin growth factor-1 (IGF-1), and cortisol (Cor) levels. Thirty veteran athletes [10 table tennis players (TT), 10 long-distance runners (LR), 10 chess players (CP)] and 10 sedentary controls (SC) between 50 and 65 years of age participated in the study. Blood samples were obtained before and immediately after exercise to determine serum Hcy, IGF-1, and Cor levels. According to their branch, each veteran athlete performed exercise sessions (70-75% of the participants' heart rate reserve) of 10-min of warm-up followed by 40-min of table tennis, aerobic running, or chess. TT and LR groups demonstrated significant increases in the serum IGF-1, Cor, and Hcy levels from pre to post-exercise (p<0.05). In contrast, the CP group showed significant increases only in the serum Hcy levels (p<0.05). Serum IGF-1 and Hcy, in response to exercise, were not significantly different between exercise groups (p>0.05). LR group had a greater serum Cor increase than all exercise groups (p<0.05). The TT group showed significantly greater changes in serum Cor levels than the CP group (p<0.05). In conclusion, although a single bout of aerobic running and table tennis exercise induces a remarkable increase in all measured biomarkers, chess exercise only elicits an increase in Hcy levels. Although aerobic running is more effective in increasing Cor levels than other types of exercise, the current study's findings suggest that serum Hcy and IGF-1 levels in veteran male athletes are not affected by the type of exercise.
... Looking at other sports like chess, which are mentally but not physically demanding, studies found an increased sympathetic activation for professional and amateur players (Troubat et al., 2009;Fuentes-García et al., 2019). Competitive, performanceoriented esports shows very similar tendencies: Looking at professional esports players in a tournament situation, there is an increase in HR and trends toward a heightenedQ, which implies a high sympathetic activation (Behnke et al., 2019). ...
... In studies on other cognitively oriented sports such as chess, no increased metabolic response could be observed in the professional and amateur levels. However, studies have found an increased stress response in chess players of different performance levels despite the unchanged metabolic response (Troubat et al., 2009;Fuentes-García et al., 2019). At the moment, there is no literature data in the competitive esports area for comparison, but in the CG sector, the same tendencies can be observed in the metabolic reaction, as shown in this study. ...
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Introduction: Esports is practiced by millions of people worldwide every day. On a professional level, esports has been proven to have a high stress potential and is sometimes considered equivalent to traditional sporting activities. While traditional sports have health-promoting effects through muscle activity and increased energy expenditure, amateur esports could represent a purely sedentary activity, which would carry potentially harmful effects when practiced regularly. Therefore, this study aims to investigate the acute effects of esports on the cardiovascular system and energy expenditure in amateur esports players to show whether esports can be considered as physical strain or mental stress or whether amateur esports has to be seen as purely sedentary behavior. Methods: Thirty male subjects participated in a 30-min gaming session, playing the soccer simulation game FIFA 20 or the tactical, first-person multiplayer shooter Counter-Strike: Global Offensive. Respiratory and cardiovascular parameters, as well as energy expenditure, blood glucose, lactate, and cortisol, were determined pre-, during, and post-gaming. Results: There were no significant changes in oxygen uptake, carbon dioxide output, energy expenditure, stroke volume, or lactate levels. Heart rate, blood glucose and cortisol decreased through the intervention until reaching their minimum levels 10 min post-gaming (Cortisol pre : 3.1 ± 2.9 ng/ml, Cortisol post : 2.2 ± 2.3 ng/ml, p < 0.01; HR min0.5 : 82 ± 11 bpm, HR post : 74 ± 13 bpm, p < 0.01). Conclusion: A 30-min esports intervention does not positively affect energy expenditure or metabolism in amateur esports players. Therefore, it cannot provide the same health-promoting effects as traditional sports participation, but could in the long-term rather cause the same potentially health-damaging effects as purely sedentary behavior. However, it does not trigger a negative stress response in the players. Deliberate physical activity and exercise routines adapted to these demands should therefore be part of the daily life of amateur esports players.
... Previous studies have explored the mental demands and cognitive domains of the sport of chess [1,2]. Previous studies have explored the mental load and the brain activation areas during chess games [3,4]. ...
The study of mental load is an emerging research topic in the field of sport sciences. In the sport of chess, there is a need to understand the mental demands of the sport of chess in order to manage training loads. The present study aimed to analyze the electrical brain pattern of an elite chess player during different chess games: 15 + 10, blindfold 15 + 10, lightning game, and problem-solving chess tasks. The participant was a male 33-year-old chess player with 2562 points of ELO and more than 26 years of chess experience, training between 3 and 4 h a day. The 15 + 10 game consisted of 15 minutes + 10 seconds increment per move. In the blindfold game, the participant cannot see the positions of the pieces and does not touch them. In the lightning game, the participant played four consecutive one minute game. In addition, two high-level, two low-level, and two medium-level chess problems were performed. Electroencephalographic (EEG) and heart rate variability (HRV) responses were measured to assess the electrical brain pattern and autonomic modulation respectively. The participant won both games at 15 + 10 (normal and blindfold), lost three and drew one of the four lightning games, solved the two low-level and the two medium-level problems and solved one of the two high-level problems. Although in both games the player achieved victory the average player move quality measured with both pure analysis and analysis with additional limitations were lower in 15 + 10 blindfold game than in 15 + 10 game. Increments in theta and alpha power spectrums can be observed during the most demanding chess games (blindfold chess, lightning game, and the chess problem at difficult- level). Furthermore, the highest alpha power spectrum values can be observed during blindfold chess. In conclusion, this is the first study investigating the EEG pattern of a International Chess Grandmaster during a blindfold chess game. We found that in the chess games where lower performance is exhibited, theta and alpha power spectrums increased.
... Ziomkiewicz et al. (2021) found that maternal response to stress is associated with neuroendocrine alterations and breast milk changes. Moreover, chronic stress leads to lipid oxidation (Troubat et al. 2009), with breastfeeding and cortisol levels responding to relaxation interventions (Mohd Shukri et al. 2019). ...
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Puerperium may lead to memory and executive/attentional complaints that interfere with women’s daily life. This might be prevented by dietary compounds, such as neuroprotective polyphenols. Their bioactivity depends on their effects on lipid metabolism in different tissues, such as the brain, fat, and breast. Thus, a polyphenol-related cognitive improvement may be associated with changes of lipids in human milk, which are key for infant neurodevelopment. A cross-sectional study was conducted on 75 postpartum women from Córdoba (Argentina), involving several neuropsychological tests. Diet was registered to identify polyphenol intake and food pattern adherence, with sociodemographic and other psychological variables (insomnia, stress, subjective cognitive complaints) being also studied. Triacylglycerols, cholesterol, and their oxidative forms were analyzed as milk biomarkers. Multivariate statistical methods were applied. Results confirmed that women who consumed polyphenols presented better executive/attentional performance (i.e., higher correct responses, conceptual level responses, complete categories, verbal fluency; lower attentional interferences, and perseverative errors) and word retention with lower interference. Polyphenols were positively associated with milk lipids, which were higher in women with better cognition. Furthermore, they had lower oxidized triacylglycerols. In conclusion, polyphenolic intake during postpartum may improve executive/attentional functioning, memory, and milk lipid profile.
... Some studies examine the heart rates when subjects are under strain. For instance, Troubat et al. (2009) record changes in heart rate and metabolism among chess players and show heart rate rises during mental stress. ...
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Zihinsel becerinin ön plana çıktığı satranç sporunda oyuncular hem kendi hem de rakibinin hamlelerini tahmin ederek başarı elde etmeyi amaçlamaktadırlar. Bunun yanı sıra turnuva boyunca adaptasyonu ve dayanıklılığı sürdürmek içinde fiziksel uygunluk düzeyi de satranç sporcuları için önem arz etmektedir. Dolayısıyla satranç sporcularının psikolojik ve fiziksel özellikleri dikkat çeken bir durumdur. Buradan hareketle 2022 Türkiye Üniversitelerarası Satranç Turnuvasına katılan 26 profesyonel satranç sporcusu ile yapılan bu çalışmada çeşitli açık uçlu sorular yardımıyla oyuncuların psikolojik ve fiziksel özelliklerinin nitel veri yöntemi ile incelenmesi amaçlanmıştır. Veriler önceden hazırlanmış soruların gönüllü katılımcılarla yapılan odak grup görüşmeleri sırasındaki cevaplarının ses kaydı alınması yolu ile elde edilmiştir. Veri analizi için 3 uzman 1 bilirkişi dahil olmuş ve tüm verilere kod [Kn] verilmiştir. Toplam 5 sorunun her biri kendi içinde tematik içerik analizi yapılarak kategoriler altında incelenerek yorumlanmıştır. Sonuçlar satrancın eğitim ile hem engelleyici hem de destekleyici bir ilişkisi olduğu, müsabakalar anında tüm spor branşları gibi çeşitli duyguların aynı anda yaşanabildiği yönündedir.
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Sport and Exercise Psychology (SEP) often adopts physiological markers in theory and practice, and one measure receiving increasing attention is heart rate variability (HRV). This paper aimed to provide a scoping review of the use of HRV within SEP. The protocol was made available on the Open Science Framework. Study inclusion criteria were examination of HRV in SEP, using athletes or healthy populations, peer-reviewed and published in English. Exclusion criteria were non-peer reviewed work, animal studies, clinical populations, review or conference papers. In February 2022 a systematic search of Web of Science, PubMed and Sport Discus identified 118 studies (4979 participants) using HRV in sport psychology (71) or exercise psychology (47). Risk of bias was assessed via the Mixed Methods Appraisal Tool. A narrative synthesis revealed that HRV was assessed within a range of topics such as stress, overtraining, anxiety, biofeedback, cognitive performance, and sporting performance. Three key limitations within the field were discovered: limited application of theoretical frameworks, methodological issues with HRV measurement, and differing interpretations of HRV results. Future research should use vagally-mediated HRV as a marker of self-regulation and adaptation in SEP, consult relevant HRV theories prior to hypothesis development, and follow methodological guidelines for HRV. ARTICLE HISTORY
A growing literature identifies associations between subjective and biometric indicators of wellbeing. These associations, together with the ability of subjective wellbeing metrics to predict health and behavioral outcomes, have spawned increasing interest in wellbeing as an important concept in its own right. However, some social scientists continue to question the usefulness of wellbeing metrics. We contribute to this literature in three ways. First, we introduce a biometric measure of wellbeing – pulse – that hs been little used. Using nationally representative data on 165,000 individuals from the Health Survey for England and Scottish Health Surveys we show that its correlates are similar in a number of ways to those for happiness, and that it is highly correlated with wellbeing metrics, as well as self-assessed health. Second, we examine the determinants of pulse rates in mid-life (age 42) among the 9,000 members of the National Child Development Study, a birth cohort born in a single week in 1958 in Britain. Third, we track the impact of pulse measured in mid-life (age 42) on health and labor market outcomes at age 50 in 2008 and age 55 in 2013. The probability of working at age 55 is negatively impacted by pulse rate a decade earlier. The pulse rate has an impact over and above chronic pain measured at age 42. General health at 55 is lower the higher the pulse rate at age 42, while those with higher pulse rates at 42 also express lower life satisfaction and more pessimism about the future at age 50. Taken together, these results suggest social scientists can learn a great deal by adding pulse rates to the metrics they use when evaluating people’s wellbeing.
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In recent studies of the structure of affect, positive and negative affect have consistently emerged as two dominant and relatively independent dimensions. A number of mood scales have been created to measure these factors; however, many existing measures are inadequate, showing low reliability or poor convergent or discriminant validity. To fill the need for reliable and valid Positive Affect and Negative Affect scales that are also brief and easy to administer, we developed two 10-item mood scales that comprise the Positive and Negative Affect Schedule (PANAS). The scales are shown to be highly internally consistent, largely uncorrelated, and stable at appropriate levels over a 2-month time period. Normative data and factorial and external evidence of convergent and discriminant validity for the scales are also presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)
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In order to devise and evaluate standardized specimen collection procedures, we studied the influence of psychological stress on the results of commonly analysed blood components: creatine kinase, lactate dehydrogenase, total protein and albumin in serum and blood picture. In addition, serum cortisol was assayed. Two kinds of stress were used: the Stroop test, a colour conflict task, and the thrill caused by the first jump of new parachutists. More changes were observed after the parachutist test than after the Stroop test. There was a difference in the responses of males and females. Females were more sensitive, especially to the parachutist test. Most of the changes observed were interpreted as being caused by haemoconcentration, possibly related to muscular tension. Cortisol, commonly used to indicate the level of stress, did not react much and is therefore not a good index of psychological stress.
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The purpose of this paper is to point out some limits and inconsistencies in the table of nonprotein respiratory quotient that is universally used. This table, developed by Lusk in 1924, was derived from biochemical and physical data that are now outdated. A new table of nonprotein respiratory quotient, consistent with modern chemical and physical data, is proposed. The revised table is based on (a) the average composition of human triacylglycerol stores, (b) energy potential of fatty acids and glucose, and (c) the volumes occupied by one mole of oxygen or carbon dioxide (which are not ideal gases) under STPD conditions.
We have studied the following stress model: the tension caused by sitting for the theoretical part of the driving license examination. Volunteers were investigated twice, after their driving license examination and after a (stress-free) control session. The effects of the stress were investigated by studying the blood picture (differential counts), serum concentration of cortisol, and cytokine production in stimulated blood cells. Relationships between the subjective perception of stress and the physiological reaction were also investigated.This stress induced significant increase in the concentrations of cortisol and hemoglobin, and in the values of hematocrit and MCV, and in the lipopolysaccharide-induced release of IL-1beta and -6. The subjective feelings of irritability and wakefulness were also significantly higher after the exam. A significant relationship was found between the changes in the stimulated production of IL-1beta and irritability. The responsiveness to psychological stress might be influenced by the temporary mood of the subjects.
In this study, we used spectral analysis of short-term R-R and systolic arterial pressure (SAP) variabilities to estimate the changes in neural control of the circulation produced by psychological stress. The 0.1 Hz low-frequency (LF) component of R-R and SAP variabilities provided a quantitative index of the sympathetic activity controlling heart rate and vasomotion. Conversely the high-frequency (HF) respiratory component of R-R variability provided an index of vagal tone. In conscious dogs we used the seemingly stressful situation of being accompanied for the first time to the experimental laboratory as a stimulus. In human subjects we used mental arithmetic. In both cases LF of R-R and SAP variabilities increased significantly suggesting enhanced sympathetic activity both to the SA node and the vasculature. In man, the index α, a measure of the overall gain of baroreceptor mechanisms, was found to be reduced during mental arithmetic. Spectral analysis of cardiovascular variabilities thus suggests that in man and in conscious dogs psychological challenges induce a profound re-arrangement of neural control of the circulation, which appears to be characterised by sympathetic predominance and which can be monitored by this technique.
We review the recent literature examining lipid changes during stressful experiences, and the psychological and constitutional differences that influence lipid levels at rest and that may modulate lipid response to stress. Mild forms of chronic or episodic stress are apparently not associated with alterations in lipids and lipoproteins, but severe forms of real or perceived stress do appear to alter lipid levels. Acute laboratory stress is frequently associated with short-term alterations in lipids and lipoproteins, but the significance of these changes is unclear. Several individual characteristics, such as heightened neuroendocrine or autonomic reactivity to stressors, Type A component behavior, and other aspects of personality, appear to be associated with an atherogenic lipid profile. Stress may influence lipid concentrations and metabolism through a variety of physiological and behavioral mechanisms, but none have been clearly elucidated. Future research should concentrate on understanding these mechanisms.
Reduced heart rate (HR) variability is associated with increased risk of cardiac arrest in patients with coronary artery disease. In this study, the power spectral components of HR variability and their circadian pattern in 22 survivors of out-of-hospital cardiac arrest not associated with acute myocardial infarction were compared with those of 22 control patients matched with respect to age, sex, previous myocardial infarction, ejection fraction and number of diseased coronary arteries. Survivors of cardiac arrest had significantly lower 24-hour average standard deviation of RR intervals than control patients (29 +/- 10 vs 51 +/- 15 ms, p less than 0.001), and the 24-hour mean high frequency spectral area was also lower in survivors of cardiac arrest than in control patients (13 +/- 7 ms2 x 10 vs 28 +/- 14 ms2 x 10, p less than 0.01). In a single cosinor analysis, a significant circadian rhythm of HR variability was observed in both groups with the acrophase of standard deviation of RR intervals and high-frequency spectral area occurring between 3 and 6 A.M. which was followed by an abrupt decrease in HR variability after arousal. The amplitude of the circadian rhythm of HR variability did not differ between the groups. Thus, HR variability is reduced in survivors of cardiac arrest but its circadian rhythm is maintained so that a very low HR variability is observed in the morning after awakening, corresponding to the time period at which the incidence of sudden cardiac death is highest.
In this study, we used spectral analysis of short-term R-R and systolic arterial pressure (SAP) variabilities to estimate the changes in neural control of the circulation produced by psychological stress. The 0.1 Hz low-frequency (LF) component of R-R and SAP variabilities provided a quantitative index of the sympathetic activity controlling heart rate and vasomotion. Conversely the high-frequency (HF) respiratory component of R-R variability provided an index of vagal tone. In conscious dogs we used the seemingly stressful situation of being accompanied for the first time to the experimental laboratory as a stimulus. In human subjects we used mental arithmetic. In both cases LF of R-R and SAP variabilities increased significantly suggesting enhanced sympathetic activity both to the SA node and the vasculature. In man, the index alpha, a measure of the overall gain of baroreceptor mechanisms, was found to be reduced during mental arithmetic. Spectral analysis of cardiovascular variabilities thus suggests that in man and in conscious dogs psychological challenges induce a profound re-arrangement of neural control of the circulation, which appears to be characterised by sympathetic predominance and which can be monitored by this technique.