No Performance or Affective Advantage of Drinking versus Rinsing with Water during a 15-km Running Session in Female Runners

Abstract

The advantage of ingesting fluids during endurance exercise lasting < 90 min has recently been challenged, but literature confirming or disputing this case is limited, particularly for female athletes. This study examined the effects of consuming water versus mouth rinsing with water during a running time trial. Recreationally active female runners (n = 19) completed two, 15-km time trials on an outdoor course in temperate environment (~20ºC; 87% RH) separated by at least one week in a randomized cross-over study design. Participants consumed 355 ml of water (DW) during their run or mouth rinsed (MR) with water from a handheld water bottle every 3 km for 5 s with physiological, perceptual, and affective variables assessed. DW or MR did not affect completion time (79.8 ± 8.1 min and 79.2 ± 8.2 min, p = 0.23), HR (p = 0.35), or RPE (p = 0.73), respectively. Sweat losses were greater (p = 0.03) for DW: 1.47 ± 0.34 L compared to MR: 1.28 ± 0.27 L; however, thirst sensation was not significantly different for MR: 6.7 ± 1.4 compared to DW: 6.2 ± 1.6. A significant effect was exhibited for time (p < 0.01) but not condition for Feeling Scale and Felt Arousal Scale or Energetic and Tense Arousal. Carrying only one smaller fluid container for MR versus a larger or multiple water bottles/backpack systems used for water consumption can reduce fluid load carried during extended duration runs without altering performance or affect for runs of 1.0-1.5 h. MR may also be beneficial to decrease thirst without ingesting fluid for runners that limit exercise fluid consumption because of gastrointestinal discomfort concerns.

Full text

Original Research
No Performance or Affective Advantage of Drinking versus Rinsing with Water
during a 15-km Running Session in Female Runners
LAUREN N. SHAVER*1, ERIC. K. O’NEAL‡2, ERIC E. HALL‡1, and SVETLANA
NEPOCATYCH‡1
1Department of Exercise Science, Elon University, Elon, NC, USA; 2Department of Health,
Physical Education and Recreation, University of North Alabama, Florence, AL, USA
*Denotes undergraduate student author, ‡Denotes professional author
ABSTRACT
International Journal of Exercise Science 11(2): 910-920, 2018. The advantage of ingesting fluids during
endurance exercise lasting < 90 min has recently been challenged, but literature confirming or disputing this case
is limited, particularly for female athletes. This study examined the effects of consuming water versus mouth
rinsing with water during a running time trial. Recreationally active female runners (n = 19) completed two, 15-km
time trials on an outdoor course in temperate environment (~20ºC; 87% RH) separated by at least one week in a
randomized cross-over study design. Participants consumed 355 ml of water (DW) during their run or mouth rinsed
(MR) with water from a handheld water bottle every 3 km for 5 s with physiological, perceptual, and affective
variables assessed. DW or MR did not affect completion time (79.8 ± 8.1 min and 79.2 ± 8.2 min, p = 0.23), HR (p =
0.35), or RPE (p = 0.73), respectively. Sweat losses were greater (p = 0.03) for DW: 1.47 ± 0.34 L compared to MR:
1.28 ± 0.27 L; however, thirst sensation was not significantly different for MR: 6.7 ± 1.4 compared to DW: 6.2 ± 1.6.
A significant effect was exhibited for time (p < 0.01) but not condition for Feeling Scale and Felt Arousal Scale or
Energetic and Tense Arousal. Carrying only one smaller fluid container for MR versus a larger or multiple water
bottles/backpack systems used for water consumption can reduce fluid load carried during extended duration runs
without altering performance or affect for runs of 1.0-1.5 h. MR may also be beneficial to decrease thirst without
ingesting fluid for runners that limit exercise fluid consumption because of gastrointestinal discomfort concerns.
KEY WORDS: Hydration, endurance performance, affect, perceived exertion
INTRODUCTION
There is considerable debate over the most appropriate fluid intake strategies for endurance
athletes (2, 25). The American College of Sports Medicine (ACSM) guidelines recommend
individuals drink to avoid losing more than 2% of body mass during endurance exercise (25).
However, the results of a meta-analysis by Goulet et al. (15) contends that a loss in up to 4%
body mass does not mitigate cycling time trial performance in ecologically valid conditions (15).
In temperate, and even hot environmental settings, most runners attain sweat losses
significantly exceeding 2% body mass (20, 21), but are unlikely to surpass 4% loss in body mass
for events of half-marathon distance (19). Training or competition scenarios in this 2-4% body

Int J Exerc Sci 11(2): 910-920, 2018
International Journal of Exercise Science http://www.intjexersci.com
911
mass loss range create the most confusion in giving appropriate advice to runners to optimize
performance.
Dion et al. (12) demonstrated that although consuming water to maintain < 2% body mass loss
provides cardiovascular and thermoregulatory advantages, this strategy does not improve half-
marathon treadmill running performance in the heat (30 °C) compared to drinking ad libitum.
The volume of water ingested when limiting body mass loss to < 2% was 3.5 times greater than
consumed when runners drank ad libitum (12). Carrying the volume of fluid required by Dion
et al. (12) to meet suggested ACSM guidelines would require a considerable number of water
bottles to be carried or a backpack style hydration vest for an unassisted run. Likewise, ingesting
close to 2 L of fluid from standard 237 mL race aid stations style cups during competition would
be untenable for most runners without pace mitigation. Both strategies would likely inhibit
optimal running economy and performance, however a handheld water bottle could be a
practical alternative.
When less than optimal fluid intake is incurred between training bouts, thirst sensation increases
and performance decreases during runs in warm environments (9, 10). It is unknown if mouth
rinsing alone would alleviate thirst/mouth dryness and curtail performance decrement under
these conditions. However, if runners begin training bouts or competition expected to elicit 2-
4% body mass loss euhydrated, simply using carried fluid to rinse in the mouth to reduce thirst
sensation might be sufficient to maintain optimal performance and easy to carry. There appears
to be only one investigation that has examined the effects of rinsing versus ingesting water
during endurance exercise. Arnaoutis et al. (3) found that consuming 100 mL of water improved
cycling time to exhaustion performance when compared to mouth rinsing or a control treatment,
despite no physiological or perceptual benefit. On the other hand, Backhouse et al. (4) found
that consuming water before and every 20 minutes during a 90 min run at 70% VO2 max resulted
in a trend of increasing perceived pleasure from pre-run versus a pattern of increasing
displeasure when no water was consumed. Like Arnaoutis et al. (3), heart rate and RPE were
not different between sessions despite the prolonged duration of exercise, but thirst rating
increased at 40 min of exercise for the no consumption group versus ingestion trial (4).
The effects of rinsing versus ingesting water are not well understood, therefore, the purpose of
the study was to examine 15-km time trial performance and physiological and affective domain
outcomes when consuming versus mouth rinsing with water in female runners in which
environmental conditions and run duration were expected to elicit sweat losses between 2-4%
of body mass. An additional aim of this study was to further examine the accuracy in which
female runners estimate their sweat losses.
METHODS
Participants
Recreationally trained female runners (n = 23) between the ages of 18 and 45 (26 ± 6.5 y) who
completed 34 ± 11 km of running per week with an average best time of 116 ± 9 min (n = 17) for
half marathon (21.1 km) were recruited for this study. However, data from 4 participants were
excluded from further analysis due to significant environmental and sweat loss differences

Int J Exerc Sci 11(2): 910-920, 2018
International Journal of Exercise Science http://www.intjexersci.com
912
between outdoor running trials. Each participant read and signed an informed consent form
prior to participation. All procedures were approved by the local Institutional Review Board
prior to participants signing informed consent. During the screening session height (165 ± 5 cm)
and weight (60.3 ± 7.1 kg) were measured (Seca 700, Chion, CA). Body fat % (22 ± 4%) was
estimated using bioelectrical impedance analysis (BF 306, OMRON, Bannockburn, IL).
Protocol
A randomized cross-over study design was used for this study. Two treatment sessions that
included a 15-km outdoor time trial separated by 9 ± 3 days were completed. Water was chilled
(5-6° C) before the trials and warmed with the environment during the run with no intervention
to keep the water chilled once running began. During the time trials, participants either
consumed water (DW) or mouth rinsed with water (MR). Participants were instructed to drink
~ 90 ml of water at 3, 6, 9, and 12 kilometers for a total of 355 ml or rinse for 5 s every 3 kilometers
from a hand-held water bottle (Amphipod, Inc., Seattle, WA) without stopping. Before
beginning the run, participants were informed of where they were to drink or rinse using a map.
They were reminded of the specific location after each lap. To help approximate the volume of
water to be consumed, the bottle was demarcated with a marker into 5 even portions.
Participants were allowed to maintain their normal physical activity throughout the study but
were asked to avoid any strenuous exercise that would cause soreness or severe tiredness 24
hours prior each session and refrain from alcohol, and coffee consumption. They were also asked
to consume a similar dinner the night before each trial and 1000 ml of water to ensure similar
euhydration levels the following morning.
All trials commenced between 6:30-9:00 am depending on each individual’s schedule,
approximately 45-60 minutes after the participants consumed a standardized breakfast
consisting of a granola bar, banana, and 500 ml of water at home. After, reporting to the lab
participants provided a urine sample to determine urine specific gravity (USG) and urine color.
Urine color was recorded using an 8-point scale (1) and USG was measured with a manual
refractometer (ATA-2771, ATAGO U.S.A. Inc., Bellevue, WA). After subjects provided a urine
sample, nude body mass was measured to the nearest 0.1 kg (BF-679W/BF-680W, TANITA,
Arlington Heights, IL). Participants were then fitted with a heart rate (HR) monitor (Polar
Team2, Polar Electro, Kempele, Finland) before walking to the start/finish line of the running
course located outside the laboratory. HR was monitored throughout the time trial and session
HR was recorded as participants finished 15-km using the Polar Team2 software system. The 15-
km time trial was performed on a well-marked, mainly flat outdoor 5-km course (3 laps). All of
the run was performed on either concrete walkways or asphalt roads. Temperature and relative
humidity were recorded at the start of each trial using a mobile weather application (The
Weather Chanel App, Atlanta, GA). Time to complete each lap and overall time were assessed
with a standard stopwatch. Participants had five minutes to recover after 15-km time trial before
completing body mass measurement to determine sweat loss. During recovery, participants
walked back to the laboratory and were allowed to stretch keeping it consistent between trials.
Participants completed the Feeling Scale (FS) and Felt Arousal Scale (FAS) before, at the 5-km
and 10-km mark, immediately after finishing, and 15 minutes post-trial. A large FS and FAS was

Int J Exerc Sci 11(2): 910-920, 2018
International Journal of Exercise Science http://www.intjexersci.com
913
visually presented to the participants at the beginning/end of each lap. Participants were
instructed to verbally rate their FS and FAS to investigators as they passed without stopping.
The FS (16) was used to assess the affective valence of participants during exercise on an 11-
point scale (+5 – very good to -5 – very bad and 0 – neutral). The FAS (26) measures arousal on
a 6-point scale (1 – low arousal to 6 – high arousal). The Activation-Deactivation Adjective
Checklist (AD ACL) (27) was administered before and immediately after each trial to assess
levels of activation and arousal using a self-rated test with 20 adjectives on a four point scale (1
– not at all and 4 – very much so). The AD ACL determines two bipolar dimensions: energetic
and tense arousal. The FS and FAS as well as the energetic and tense arousal were used to
measure the circumplex model of affects (24).
Stomach fullness and thirst sensation were collected before and after each trial. Stomach fullness
was measured on a scale 0-10 (0 – empty/extremely hungry and 10 – extremely full) and the
thirst sensation was measured on a scale 0-9 (0 – not thirsty at all and 9 – very, very thirsty) (13).
Session rate of perceived exertion (RPE) was measured immediately after the run was completed
on a 6-20 scale (6).
After each trial, participants were asked to verbally estimate how much sweat they thought they
lost during the run rounded to the nearest 30 mL. Participants were presented with an empty
experimental water bottle and informed that the water bottle used during the run held 360 mL
of water for a visual reference.
Statistical Analysis
Repeated measures ANOVA (time to complete each 5-km loop, thirst sensation, stomach
fullness, FS and FAS) and paired-samples t-test were used to analyze differences in dependent
variables (USG, urine color, body weight, total running time, HR, session RPE, sweat rate and
sweat loss) between DW or MR. All statistical analyses were performed using SPSS Version 22.0
(SPSS Inc., Chicago, IL, USA). Mauchlys’s Test of Sphericity was used to test the assumption of
sphericity. Data are presented as mean ± standard deviation, with the significance level set at p
< 0.05.
RESULTS
Runners reported to the laboratory equally euhydrated based on USG (DW = 1.010 ± 0.007; MR
=1.008 ± 0.006; p = 0.21 and urine color (DW = 2.8 ± 1.3; MR =2.5 ± 1.3; p = 0.13). Pre-run body
mass was lower for the DW session (DW = 59.7 ± 7.1; MR = 60.0 ± 7.1 kg; p = 0.03). There was no
significant difference in temperature (20.1 ± 3.0 ºC and 19.8 ± 2.6 ºC, p = 0.68), relative humidity
(85.3 ± 9.4% and 86.6 ± 10.4%, p = 0.68), session HR (180 ± 16 bpm and 178 ± 14 bpm, p = 0.35),
or session RPE (16.0 ± 2.0 and 16.4 ± 1.7, p = 0.73) between DW and MR conditions respectively.
Likewise, there were no differences in overall time trial performance (79.8 ± 8.1 and 79.2 ± 8.2
min, p = 0.23) for DW and MR conditions, respectively. Individual 15-km time trial results are
displayed in Figure 1. Individual data indicated that there were 4 runners that ran 2% faster
during drinking and 8 runners that ran 2% faster during rinsing. There was no significant
treatment effect (p = 0.23) for 5-km split times; however, the main effect for lap number
approached significance (p = 0.07) for individual 5-km split times at 1st 5-km (26.2 ± 2.6 and 26.1

Int J Exerc Sci 11(2): 910-920, 2018
International Journal of Exercise Science http://www.intjexersci.com
914
± 2.7), 2nd 5-km (26.4 ± 3.1 and 26.1 ± 2.9) or 3rd 5-km (27.1 ± 3.0 and 26.8 ± 2.9) for DW and MR
conditions, respectively.
Figure 1. 15-km Time trial individual data (n = 19). DW – drinking water, MR – mouth rinsing. Solid lines represent
<2% change in performance between trials. Long dash, solid fill marker represent >2% decrease in performance
during MR versus DW. Short dash, no fill markers represent >2% decrease in performance during DW versus MR.
Participants experienced significantly greater sweat loss (p = 0.03), sweat rate (p = 0.03) and %
body weight loss (p = 0.01) during DW (Table 1). There was no significant difference in
estimated absolute sweat loss (p = 0.34) or percent of actual sweat loss (p = 0.57) between DW
and MR conditions; however, participants significantly (p < 0.001) underestimated how much
sweat they actually lost in each treatment session (Table 1).
Table 1. Hydration and sweat loss estimate outcomes (n = 19; M ± SD).
Sweat Loss (L)
Sweat Rate (L/h)
Post-run Sweat Loss Estimation
Body mass loss (%)
Absolute (L)
% of Actual Sweat Loss
DW
1.44±0.34*
1.05±0.24*
2.4±0.6*
0.69±0.92†
47.8±56.0
MR
1.23±0.28
0.93±0.23
2.1±0.5
0.54±0.58†
42.8±44.1
DW – drinking water, MR – mouth rinsing. *Significantly different from MR p < 0.05. †Significantly different
within treatment versus actual sweat loss p < 0.05
60
65
70
75
80
85
90
95
100
DW MR
Finishing Time (min)

Int J Exerc Sci 11(2): 910-920, 2018
International Journal of Exercise Science http://www.intjexersci.com
915
There was a significant main effect for time (p < 0.001) but not for treatment (p = 0.10) or
interaction time by treatment (p = 0.70) observed for thirst sensation (Table 2). Thirst did not
differ between pre- or post-run between treatments, however, thirst ratings increased with time
as would be expected. There was a significant main effect for time (p < 0.001) but not for
treatment (p = 0.92) observed for stomach fullness (Table 2). Stomach fullness did not differ
between DW and MR treatment conditions, however, it decreased over time. In addition, a
significant time by treatment interaction was observed (p = 0.04) where greater decrease in
stomach fullness was observed in MR conditions compared to DW.
There were no significant differences in condition or condition by time effect for FS and FAS;
however, there was a significant time effect (p < 0.001). Univariate analyses revealed that this
was due to changes in both FS (p <0 .001) as well as FAS (p < 0.001). For the FS, compared to
baseline there was a non-significant trend towards an increase in negative valence at 10-km (p =
0.06) and 15-km (p = 0.08), but affect valence became more positive at 15 min post-run (p = 0.003).
FAS was found to increase at every time point following baseline (p < 0.001). See Figure 1 for a
graphical depiction of the results for FS and FAS. Energetic and tense arousal exhibited no
significant condition or condition by time interaction, but the main effect for time was significant
(p < 0.001). This was a result of significant changes in energetic arousal (p < 0.001) and tense
arousal (p = 0.01) over time. When plotted on the circumplex model there was a significant
increase in valence and arousal (see Figure 2).
Table 2. Thirst and stomach fullness responses (n = 19; M ± SD).
DW
MR
Pre
Post
Pre
Post
Thirst Sensation
3.6±1.9
6.2±1.6†
4.1±1.6
6.7±1.4†
Stomach Fullness
6.7±1.4
5.2±1.8†
7.2±1.4
4.6±1.3†
DW – drinking water; MR – mouth rinsing; Thirst Sensation Scale (0-7); Stomach Fullness Scale (0-10).
†Significantly different within treatment from pre-run p < 0.05
Figure 2. Feeling Scale (FS) and Felt Arousal
Scale (FAS) responses to drinking vs rinsing
over time. Solid and dashed line represents MR
- mouth rising and DW - water drinking,
respectively.

Int J Exerc Sci 11(2): 910-920, 2018
International Journal of Exercise Science http://www.intjexersci.com
916
DISCUSSION
It is unequivocal that regardless of environmental conditions during longer races (e.g. the
marathon), where sweat losses can easily exceed 4% body mass, that nearly all runners will
choose to and should drink during competition. This is also true during shorter distance races
such as a half-marathon that are conducted in the heat (7, 12, 19). However, during running
bouts that will elicit greater than 2% loss in body mass, but not more than 4% loss in body mass,
the efficacy for fluid ingestion to improve endurance performance is unclear. Thus, the purpose
of this study was to examine differences in physiological and affective responses and
performance under such training conditions for well-trained but recreational female runners
when drinking versus mouth rinsing with water. The main finding of the current study was that
ingestion of fluid was not advantageous compared to mouth rinsing during a 15-km outdoor
running time trial (Figure 1).
The current authors are aware of only one other investigation (3) in which water ingestion versus
mouth rinse has been examined. Arnaoutis et al. (3) found improved cycling performance in 10
trained, but non-elite men when consuming only 100 ml of water compared to rinsing with
water. Arnaoutis et al. (3) postulated the act of swallowing and ingestion of chilled fluids could
activate oral-pharyngeal receptors and in turn prolong exercise capacity. While the authors’
hypothesis was confirmed in contrast to the findings of the current investigation, it is critical to
examine methodological differences implemented. Arnaoutis et al. (3) study completed their
performance task following a 10-hour fast and a pre-performance test that consisted of 4 bouts
of low intensity running or cycling for 25 min followed by 5 min of passive rest to elicit 2%
dehydration prior to performance testing (3). In total, the dehydration protocol included 100
min of exercise and 20 minutes of passive rest in a hot environment (31 ˚C). The performance
task conducted was also a time trial to exhaustion which have been shown to have much higher
Figure 3. Energetic Arousal (EA) and Tense
Arousal (TA) responses to drinking vs rinsing
over time. Solid and dashed line represents MR
- mouth rising and DW - water drinking,
respectively.

Int J Exerc Sci 11(2): 910-920, 2018
International Journal of Exercise Science http://www.intjexersci.com
917
coefficient of variations than simple time trials (18). In contrast, the present study attempted to
replicate a more ecologically valid scenario in regards to training or competition conditions.
Sweat losses were induced during the simulated competition protocol only. Runners also began
exercise euhydrated and consumed a light breakfast 45-60 minutes before the run. Although
the time trial to exhaustion in (3) was not performed under hot conditions, it is plausible the 2 h
of thermoregulatory challenge prior to the performance task initiated an increased central drive
attributed to an oral-pharyngeal response of cold fluid ingestion. However, under such training
or race conditions it seems unlikely most runners would fail to ingest fluids if available, but
there is no evidence that this ergogenic effect exists during hard runs of 70-90 min in temperate
environmental conditions.
A concerted effort was made to create a drinking volume that would optimize the opportunity
for fluid ingestion to improve performance while limiting risk of stomach discomfort. The
volume of fluid selected was also chosen to minimize running economy and kinematic impact
from carrying a greater fluid mass. Dion et al. (12) found considerably greater abdominal
discomfort when participants consumed water ad libitum versus drinking to keep body mass
loss below 2% during a treadmill half-marathon in the heat (12). As would be expected,
participants felt less stomach fullness from the beginning to the end of the running session
regardless of treatment difference (Table 2). The faster pace of the male runners in (12) resulted
in similar duration of exercise to the current study. Despite drinking on average 225 mL and
1,705 mL more compared to the present study in the to-thirst and maintaining less than 2% body
weight loss, respectively, Dion et al. (12) did not find a significant difference in perceived thirst
until the 20-km mark of the half marathon. Likewise, simply rinsing fluids resulted in no
difference in thirst sensation difference (Table 2) in the current study. Akin to thirst sensation
and stomach discomfort, fluid ingestion failed to reduce cardiovascular drift or increase session
RPE in the present study. These results support previous investigations that suggest fluid intake
has little to no effect on cardiovascular responses or perceived exertion under similar exercise
tasks and conditions (3, 5, 8, 14, 23).
A study by de Araujo et al. (11) demonstrated that water activates both the primary and
secondary taste cortex. When individuals are thirsty, both consuming water and delivering
water into the mouth produced feelings of pleasantness and showed activation in the
orbitofrontal cortex (11). Thus, the reward of both drinking water and rinsing with water
activate the same part of the brain. This may help to explain why participants did not feel
different during the run, which may have a positive impact on performance as well. Similar to
Hall et al. (16), participants tended to feel worse and more aroused during exercise (16). After
exercise, participants felt better and levels of arousal decreased with ingestion resulting in no
improvement in affective domain responses (Figures 2 and 3).
Application of nearly all of the current guidelines for hydration strategies promoted by the
ACSM (25) require accurate estimation of sweat losses assessed by change in pre- to post-
exercise body mass, but this practice is not common in the running community (22). Previous
studies suggest that most, but not all runners will adequately rehydrate between training bouts
and that the majority of runners underestimate their sweat losses by ~50% (20,21). This

Int J Exerc Sci 11(2): 910-920, 2018
International Journal of Exercise Science http://www.intjexersci.com
918
phenomenon was further confirmed in the current study with nearly identical levels of
underestimation of sweat losses (Table 1) in a large group of trained but non-elite female runners
and highlights the need for greater promotion of the concept of implementing sweat loss
assessment techniques to optimize between bout fluid intake strategies and prevent over or
underestimation of fluids during long duration runs.
The major limitation of this study is that environmental conditions could not be standardized
between trials. However, the exclusion of data from participants that ran under significantly
different temperatures and humidity has hopefully mitigated this limitation. Specific dietary
and training habits may not have been similar between trials, as participants were not asked to
record to ensure compliance. Participants did not engage in formal 15-km training nor ran the
distance very often, which could have affected the results. In addition, some participants had
only 6-7 days to recover in between the trials, however, similar recovery time was previously
used for a half marathon distance by Dion et al. (12). Therefore, considering a shorter distance
in the present study the time in between the trials would be sufficient enough to recover for
most participants and would not have an effect on performance. Lastly, the inability to monitor
whether participant consumption of water during the rinsing trial may have influenced their
physiological and psychological responses.
In conclusion, ingestion of fluid during runs of 70-90 min that produce greater than 2 but less
than 4% loss in body mass from sweating did not improve run performance, alter heart rate,
stomach discomfort, and thirst sensation, or improve affective domain responses versus rinsing
when runners began exercise in a euhydrated state. Carrying fluid for rinsing versus
consumption can reduce the volume of fluid to be transported by the runner. Assessment of
change in body mass during runs can help runners identify their fluid consumption needs
between training bouts. All runners in this investigation began exercise euhydrated. Future
investigations examining the effects of mouth rinsing versus fluid ingestion when inadequate
between bout fluid replacement takes place is warranted.
ACKNOWLEDGEMENTS
The authors would like to thank all of the participants who kindly donated their time to
participate in the study. Elon University helped to make this study possible by providing
resources and opportunity.
REFERENCES
1. Armstrong L, Maresh C, Castellani J, Bergeron M, Kenefick R, LaGrasse K, et al. Urinary indicies of hydration
status. Int J Sport Nutr 4(3): 265–279, 1994.
2. Armstrong LE, Casa DJ, Emmanuel H, Ganio MS, Klau JF, Lee EC, et al. Nutritional, Physiological, and Perceptual
Responses During a Summer Ultraendurance Cycling Event: J Strength Cond Res 26(2): 307–318, 2012.
3. Arnaoutis G, Kavouras SA, Christaki I, Sidossis LS. Water Ingestion Improves Performance Compared with
Mouth Rinse in Dehydrated Subjects: Med Sci Sport Exerc 44(1): 175–179, 2012.

Int J Exerc Sci 11(2): 910-920, 2018
International Journal of Exercise Science http://www.intjexersci.com
919
4. Backhouse SH, Biddle SJH, Williams C. The influence of water ingestion during prolonged exercise on affect.
Appetite 48(2): 193–198, 2007.
5. Beelen M, Berghuis J, Bonaparte B, Ballak SB, Jeukendrup AE, van Loon LJC. Carbohydrate mouth rinsing in the
fed state: lack of enhancement of time-trial performance. Int J Sport Nutr Exerc Metab 19(4): 400–409, 2009.
6. Borg GA. Psychophysical bases of perceived exertion. Med Sci Sports Exerc 14(5): 377–381, 1982.
7. Byrne C, Lee JKW, Chew SAN, Lim CL, Tan EYM. Continuous thermoregulatory responses to mass-participation
distance running in heat. Med Sci Sports Exerc 38(5): 803–810, 2006.
8. Carter JM, Jeukendrup AE, Jones DA. The effect of carbohydrate mouth rinse on 1-h cycle time trial performance.
Med Sci Sports Exerc 36(12): 2107–2111, 2004.
9. Casa DJ, Stearns RL, Lopez RM, Ganio MS, McDermott BP, Walker Yeargin S, et al. Influence of Hydration on
Physiological Function and Performance During Trail Running in the Heat. J Athl Train 45(2): 147–156, 2010.
10. Davis BA, Thigpen LK, Hornsby JH, Green JM, Coates TE, O’Neal EK. Hydration kinetics and 10-km outdoor
running performance following 75% versus 150% between bout fluid replacement. Eur J Sport Sci 14(7): 703–710,
2014.
11. de Araujo IE, Kringelbach ML, Rolls ET, McGlone F. Human Cortical Responses to Water in the Mouth, and the
Effects of Thirst. J Neurophysiol 90(3): 267–275, 2003.
12. Dion T, Savoie FA, Asselin A, Gariepy C, Goulet EDB. Half-marathon running performance is not improved by
a rate of fluid intake above that dictated by thirst sensation in trained distance runners. Eur J Appl Physiol 113(12):
3011–320, 2013.
13. Engell, DB, Maller, O, Sawka, MN, Francesconi, RN, Drolet, L, and Young A. Thirst and fluid intake following
graded hypohydration levels in humans. Physiol Behav 40: 229–236, 1987.
14. Gam S, Guelfi KJ, Fournier PA. Opposition of carbohydrate in a mouth-rinse solution to the detrimental effect
of mouth rinsing during cycling time trials. Int J Sport Nutr Exerc Metab 23(1): 48–56, 2013.
15. Goulet EDB. Effect of exercise-induced dehydration on time-trial exercise performance: a meta-analysis. Br J
Sports Med 45(14): 1149–1156, 2011.
16. Hall EE, Ekkekakis P, Petruzzello SJ. The affective beneficence of vigorous exercise revisited. Br J Health Psychol
7(Pt 1): 47–66, 2002.
17. Hardy CJ, Rejeski WJ. Not what, but how one feels: the measurement of affect during exercise. J Sport Exerc
Physiol 11: 304–317, 1989.
18. Laursen PB, Francis GT, Abbiss CR, Newton MJ, Nosaka K. Reliability of time-to-exhaustion versus time-trial
running tests in runners. Med Sci Sports Exerc 39(8): 1374–1379, 2007.
19. Lee JKW, Nio AQX, Lim CL, Teo EYN, Byrne C. Thermoregulation, pacing and fluid balance during mass
participation distance running in a warm and humid environment. Eur J Appl Physiol 109(5): 887–898, 2010.
20. O’Neal EK, Caufield CR, Lowe JB, Stevenson MC, Davis BA, Thigpen LK. 24-h fluid kinetics and perception of
sweat losses following a 1-h run in a temperate environment. Nutrients 6(1): 37–49, 2013.

Int J Exerc Sci 11(2): 910-920, 2018
International Journal of Exercise Science http://www.intjexersci.com
920
21. O’Neal EK, Davis BA, Thigpen LK, Caufield CR, Horton AD, McIntosh JR. Runners greatly underestimate sweat
losses before and after a 1-hr summer run. Int J Sport Nutr Exerc Metab 22(5): 353–362, 2012.
22. O’Neal EK, Wingo JE, Richardson MT, Leeper JD, Neggers YH, Bishop PA. Half-marathon and full-marathon
runners’ hydration practices and perceptions. J Athl Train 46(6): 581–591, 2011.
23. Rollo I, Williams C, Nevill M. Influence of ingesting versus mouth rinsing a carbohydrate solution during a 1-h
run. Med Sci Sports Exerc 43(3): 468–475, 2011.
24. Russell JA. A circumplex model of affect. J Pers Soc Psychol 39(6): 1161–1178, 1980.
25. Sawka MN, Burke LM, Eichner ER, Maughan RJ, Montain SJ. American College of Sports Medicine position
stand. Exercise and fluid replacement. Med Sci Sports Exerc 39(2): 377–390, 2007.
26. Svebak S, Murgatroyd S. Metamotivational dominance: A multi-method validation of reversal theory
constructs. J Personal Psychol 48: 107–116, 1985.
27. Thayer RE. Activation-deactivation adjective check list: Current overview and structural analysis. Psychol Rep
58: 607–614, 1986.