Contents
- 1 Abstract
- 2 Introduction
- 3 Methods
- 3.1 Participants.
- 3.2 Experimental design.
- 3.3 Procedures.
- 3.4 Exercise dehydration protocol.
- 3.5 Physiological variables at rest.
- 3.6 Cognitive test battery.
- 3.7 Cognitive testing at rest.
- 3.8 Scanning visual vigilance task.
- 3.9 PVT.
- 3.10 Four-choice visual reaction time test.
- 3.11 Matching to sample test.
- 3.12 Repeated acquisition test.
- 3.13 Grammatical reasoning.
- 3.14 POMS questionnaire.
- 3.15 VAS.
- 3.16 Cognitive testing during exercise.
- 3.17 Statistical methods.
- 4 Results
- 5 Discussion
- 6 Acknowledgments
- 7 Literature Cited
- 8 Abbreviations
- 9 Author notes
Abstract
limited information is available regarding the effects of balmy dehydration on cognitive function. therefore, meek dehydration was produced by intermittent chasten use without hyperthermia and its effects on cognitive function of women were investigated. twenty-five females ( senesce 23.0 ± 0.6 yttrium ) participated in three 8-h, placebo-controlled experiments involving a different hydration state of matter each day : exercise-induced dehydration with no diuretic drug ( DN ), exercise-induced dehydration plus diuretic drug ( DD ; furosemide, 40 milligram ), and euhydration ( EU ). cognitive operation, temper, and symptoms of dehydration were assessed during each experiment, 3 times at rest and during each of 3 drill sessions. The DN and DD trials in which a unpaid attained a ≥1 % flush of dehydration were pooled and compared to that volunteer ‘s equivalent EU trials. Mean dehydration achieved during these DN and DD trials was −1.36 ± 0.16 % of soundbox mass. significant adverse effects of dehydration were present at rest and during exercise for vigor-activity, fatigue-inertia, and sum climate perturbation scores of the Profile of Mood States and for job trouble, concentration, and headache as assessed by questionnaire. Most aspects of cognitive performance were not affected by dehydration. Serum osmolality, a marker of hydration, was greater in the entail of the dehydrate trials in which a ≥1 % charge of dehydration was achieved ( P = 0.006 ) compared to EU. In decision, degraded mood, increased sensing of tax difficulty, lower concentration, and concern symptoms resulted from 1.36 % dehydration in females. Increased emphasis on optimum hydration is warranted, specially during and after chasten use .
Introduction
Adequate fluid intake and homeostasis of full body urine is essential for human health and survival, including maintaining brain routine. dangerous dehydration clearly produces decrements in cognitive serve ( 1, 2 ). For exemplar, clinical observations demonstrate severe dehydration results in acute confusion and craze ( 3 ). however, insufficient research has been conducted to determine if meek dehydration, at levels that may occur in healthy individuals during their ordinary daily activities, degrades cognitive performance, alters mood, or produces adverse symptoms. many studies use heat and practice to produce dehydration. One of the most comprehensive examination ( ambient temperature of 45°C with 30 % RH8 ) assessed the effects of dehydration ranging from 1 to 4 % in 1 % increments in 11 goodly, young males aged 20–25 yttrium ( 4 ). A serial summation test, son recognition test, and trail-making test were administered ; all detected deterioration at 2–4 % dehydration. A exchangeable cogitation ( 5 ) assessed the effects of dehydration at ~1, 2, and 3 % consistency aggregate loss in 8 young males. Moderate exercise in the heat induce dehydration and behavioral quiz was conducted in three environments : thermoneutral ( 37°C, 50 % RH ), hot dry ( 45°C, 30 % RH ), and hot humid ( 39°C, 60 % RH ). Tests included symbol substitution, concentration, and eye-hand coordination. Effects of dehydration were observed in two of three tests at 2 and 3 % dehydration, but, in the symbol substitution examination, effects were observed entirely at 3 % dehydration ( P < 0.05 ). other studies assessed data work during simulate sporting events with exchangeable outcomes ( 6 – 8 ) ; dehydration ( from −1 to −4 % body mass ) impaired mood, choice reaction time, and watchfulness. jointly, these studies provide insight into the effects of mild-to-moderate dehydration on cognitive performance but not a clear indication of which aspects of cognitive performance are most affect by dehydration or its effects on temper, perceived feat, or symptoms. furthermore, the high levels of heating system used to induce dehydration may have interacted with dehydration to exacerbate degradation of cognitive performance ( 1 ).
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The present investigation used a battery of tests of cognitive performance, temper, perceived effort, and symptoms sensitive to versatile environmental and nutritional factors, including balmy dehydration ( 9 – 11 ). To avoid confounding effects of high heat exposure, mild dehydration was induced by mince exercise in a moderately warm environment ( mean ± SD, 27.6 ± 0.8°C ). physiologic variables associated with hydration country were besides assessed. Volunteers were healthy, young females. A problem with previous work in this area is the difficulty designing a double-blind study of dehydration ( 1 ). consequently, this report disguised the treatment conditions from volunteers and investigators creditworthy for testing by using several procedures. inclusion of a positive control condition, dehydration induced by combination of a diuretic drug and exercise, disguised the experimental conditions, because in one of two dehydration experiments, volunteers lost significant fluid in urine. To far blind the experimental conditions, a pill ( either diuretic drug or placebo ) was administered prior to every experiment and some fluid, with the volume disguised, was consumed. We hypothesized meek dehydration would primarily affect temper and symptoms of dehydration and have meek effects on cognitive function.
Methods
Participants.
twenty-five females ( age, 23.0 ± 0.6 yttrium ; body mass, 63.0 ± 10.3 kilogram ) attended an informational briefing and gave informed voluntary accept to participate in this study, which was approved by the University of Connecticut Institutional Review Board for Human Studies. The women were selected from 30 volunteers. Any womanhood who consumed an extreme diet, had testify of broken feed, was taking medications that altered fluid-electrolyte remainder, was restricting thermal intake, or had a chronic disease ( for example, nephritic dysfunction ) was excluded from participation. Use of oral contraceptives for at least three consecutive months prior to this investigation was an inclusion body standard. Test participants were physically fit ( i.e., could complete three walking exercise sessions/d ) but were neither highly prepare nor wholly sedentary. prior to this probe, most participated in 30–60 min of exercise on 2–4 d/wk. All participants spoke English as their primary coil lyric.
Experimental design.
In this crossover voter study, women participated in 3-day-long testing ground experiments : 1 ) exercise-induced dehydration plus placebo encapsulate containing no diuretic drug ( DN ) ; 2 ) exercise-induced dehydration plus a diuretic drug capsule ( DD ) ; and 3 ) euhydration plus placebo space capsule ( EU ). The order of assignment to each of the experiments was randomized. All experiments involved an identical exercise regimen, described below. A third gear party, not involved in data solicitation, randomized and counterbalanced the order of experiments. Test participants ampere well as investigators in the environmental bedroom were unaware of the treatments, but an detective who monitored water system administration was not. The 3 experiments were conducted ~28 five hundred aside during the 7-d placebo phase of each woman ‘s oral contraceptive schedule. Prior to each experiment, participants presented their vacate oral contraceptive pill packs to a female detective to verify they were in the placebo phase of their contraceptive schedule. Because experiments were separated by 28 d to control for the menstrual bicycle, males were not tested in this study. however, a disjoined study of males was conducted using a exchangeable protocol during a different period of time.
Procedures.
To become familiar with learn procedures, each participant visited the testing ground for 3–5 preliminary sessions to exercise cognitive tests and behavioral testing on a desktop calculator while sitting at a workstation and a laptop computer while walking on a treadmill. When a woman ‘s cognitive performance reached an asymptote on 2 consecutive days, she could participate in experiments. Participants were instructed regarding adequate fluid intake and sleep anterior to each experiment and refrained from consuming caffeine and alcohol for 12 h prior to each. To ensure all participants began each experiment in a euhydrated country, they consumed 240 milliliter of auxiliary mineral water ( i.e., above their usual/habitual water consumption ) on the night before testing and 240 milliliter of mineral water upon waking on the good morning of testing. This was supplied as Volvic Natural Mineral Water ( Danone ), which contained the following dissolved substances ( mg/L ) : calcium, 10 ; chloride, 8 ; bicarbonate, 65 ; magnesium, 6 ; nitrate, 1 ; potassium, 6 ; silica, 30 ; sodium, 9 ; and sulfates, 7 ( 109 mg/L of sum dissolve solids ). The mineral water besides was consumed with a standardized breakfast and during the experiments ( see below ). Further, participants consumed the like meals for 24 h prior to each experiment to reduce the effects of variation in nutritional inhalation on consequence variables. The foods and beverages consumed prior to the beginning experiment ( i, self-selected by each player ) were duplicated for the second and third experiments. conformity was verified with dietary records of all food and beverages consumed during the 24 hydrogen before each experiment. On the good morning of each experiment, participants reported to the testing ground at 0800 or 0900 planck’s constant and, after a rake sample was collected, consumed one capsule under the supervision of an research worker. Capsules were prepared by a license pharmacist ( compound Solutions in Pharmacy ), were identical in appearance, and contained either a diuretic drug ( 40 milligram furosemide ; Lasix ) or placebo. Volunteers reported at two unlike times so testing could be staggered ( times provided in the textbook are for women starting at 0800 heat content ). Participants rested quietly in an anteroom adjacent to the test rooms and consumed no food until 1000 h when a standardized breakfast was provided ; it contained ~700 kcal ( 2929 kJ 9 ) + 174 milliliter mineral water. They besides consumed two small food bars as snacks [ 210 kcal ( 879 kJ ) /feeding ] immediately after the first ( 1350 heat content ) and second gear ( 1550 heat content ) cognitive test batteries. A blood sample was besides collected at 1750 h. At 1200, 1400, and 1600 planck’s constant, participants entered the environmental chamber and began 40 min of dehydrating drill ( described below ) then rested for 20 min. Participants began identical cognitive test batteries at 1300, 1500, and 1700 h. In the DN and DD experiments, the women consumed no water to replace water passing in urine or effort, except for 50 mL after completing the first and second cognitive trial batteries, to wet their palates and disguise the experimental condition. Procedures in the EU experiment were identical to the DN and DD experiments except fluid lost in urine and perspiration was replaced by consuming an equal bulk of mineral body of water during and after each practice bout based on the individual ‘s loss during that school term. Ambient lab environmental conditions were controlled and monitored. In the anteroom outside the environmental chamber and in the cognitive test room, breeze temperature was maintained at 23.0°C. fluid lost in urine during the experiment was assessed by collecting each woman ‘s total urine output. Sweat passing was calculated as the remainder in body aggregate, corrected for urine production and fluid consumption.
Exercise dehydration protocol.
Participants performed 40 min of treadmill walking ( 5.6 kilometers per hour, 5 % class ) in a moderate-warm environment to produce body mass passing without inducing hyperthermia. Inside the environmental chamber, where dehydrating exercise sessions were conducted, the air temperature was 27.6 ± 0.8°C, the RH was 49.4 ± 6.9 %, and the scent rush was 3.5 m/s as provided by a floor winnow. Body mass was measured ( ±50 thousand ) every 13 min during exercise when participants briefly stepped off the treadmill onto a floor scale ( Healthometer model 349KLX ). Heart rate was measured every 10 minute with a chest of drawers cardiotachometer ( model S150, Polar Instruments ). The Tgi was measured every 10 minute of practice by using an ingestible temperature detector ( CorTemp, HQ ). On the good morning of each experiment, each player swallowed the detector upon arrival to the lab. After every exercise session, participants left the environmental chamber, moved to a comfortable room ( 23.0°C, pallidly light, lull ), dried their skin and hair with a towel, and rested on a moderate for 20 min. The rating of sensed effort scale [ 6–20 point scale ( 12 ) ] was administered at 40 min of use ; the extreme options on this scale were “ very, very inner light ” and “ very, very hard. ” At the same time, a perceive leg muscle pain volume rat was obtained from each womanhood ( 13 ). This scale ranged from 0 ( “ no annoyance at all ” ) to 10 ( “ extremely intense pain, about intolerable ” ) and offered one countless evaluation option beyond 10 ( “ intolerable trouble ” ). To disguise the experimental condition, participants were unaware of their body multitude, urine volume, and absorb fluid bulk during experiments. This was accomplished by obscuring the torso multitude scale dial, collecting urine in person aliquots and removing these samples from the room before placement in the urine collection container, and by providing mineral water in opaque, covered containers. In hurt of these efforts, differences in urine menstruate between conditions may have been detectable by the women. however, upon completion of all test, volunteers were not able to distinguish between the hydrated and dehydrated experiments.
Physiological variables at rest.
A urine sample distribution was collected curtly after participants arrived at the testing ground ( 0800 heat content ) for evaluation of urine particular gravity via a hand-held refractometer. immediately preceding the final cognitive quiz battery, the Tgi was recorded at rest ( see previous section ). A lineage sample was collected when participants arrived at the lab ( 0800 planck’s constant ) and after the third cognitive screen battery ( 1700 planck’s constant ). Osmolality was measured in both samples ; lactate, glucose, and cortisol were measured in the 1700-h sample. Osmolality was measured in double using a freezing-point depression osmometer ( model 3250, Advanced Instruments ). Lactate and glucose were analyzed ( YSI 2300 Stat Plus ) in duplicate using an automated enzymatic technique. Cortisol was analyzed using a competitive hydrocortisone enzyme immunoassay technique ( ELISA, DSL-10–2000 ; Diagnostic Systems Laboratories ).
Cognitive test battery.
behavioral tasks were selected that assessed a broad spectrum of cognitive functions, from simpleton abilities to complex skills, including watchfulness, reaction time, learning, working memory, and legitimate reasoning. Mood states and symptoms were besides assessed. Testing was conducted 20 min after completing each exercise session in a tranquillity, dimly ignite room ( 23.0°C ) and took 45–50 min to complete. Computerized tasks ( NTT Systems ; Cognitive Test Software, interpretation 1.2.4 ) were administered in the lapp order during each experiment.
Cognitive testing at rest.
Testing at respite was conducted using desktop calculator systems running the Windows function organization. ocular stimuli were presented on 49-cm ( solidus ) LCD monitors ( Acer model A1716F ). participant responses were stimulation using keyboards ( Razer Tarantul, model RZ03–00070100-R2U1 ) that recorded responses with a 1-ms response latency.
Scanning visual vigilance task.
This test is medium to a wide diverseness of environmental conditions, nutritional factors, rest personnel casualty, and very low doses of hypnotic drugs and stimulants ( 14, 15 ). The player endlessly scans a calculator screen to detect the occurrence of stimuli that are infrequent and difficult to detect. The volunteer detects a faint stimulation that appears randomly on a calculator sieve, approximately once per minute, then presses the space bar on the keyboard vitamin a quickly as possible. The computer records whether or not a stimulation is detected and the answer clock ( in milliseconds ). Responses made > 2 sulfur after a stimulation was presented were recorded as false alarms. During the preliminary commit sessions, each tennessean ‘s operation was adjusted to a standard of ~60 % right detections.
PVT.
This is a test of elementary ocular reaction clock ( 16 ). A series of stimuli are presented at random intervals on a screen and the player responds deoxyadenosine monophosphate quickly as potential when a stimulation appears. reaction time, fake alarms, and number of lapses ( hanker duration responses ) are recorded. The test requires sustained care and responses, performed by pressing a button in a seasonably manner, in reaction to a randomly appearing stimulation on the calculator screen. This is the only helping of the cognitive test battery that was administered during treadmill practice.
Four-choice visual reaction time test.
Choice reaction time tasks are sensitive to the effects of nutritional factors on cognitive performance ( 10, 17 – 19 ). Volunteers are presented with a serial of ocular stimulation at one of four different spatial locations on a calculator riddle. They indicate the adjust spatial localization of each stimulation by pressing one of four adjacent keys on the computer keyboard. correct responses, wrong responses, response rotational latency, previous errors, and time-out errors ( i.e., response rotational latency > 1 s ) are recorded for each test administration.
Matching to sample test.
This test assesses short-run spatial memory ( working memory ) and blueprint recognition skills ( 17, 20 ). The volunteer is presented with a matrix of a red and green checkerboard on a coloring material screen. The matrix appears on the sieve for 4 s, then is removed during a variable star delay involving a space screen. After the check, two matrices are presented on the screen : the original sample matrix and a second gear matrix that differs slenderly ( i, the color sequence of two of the squares is reversed ). The volunteer selects the comparison matrix by touching keys that match the original sample distribution matrix. The task lasts ~5 min. If a reception is not made within 15 s, a time-out error is recorded. correct responses and the answer time to choose a matrix besides are recorded.
Repeated acquisition test.
This test assesses learning and short-run memory ( 17 ). The volunteer is required to learn a sequence of 12 key presses on the four arrow keys of a calculator ; this job requires ~10 minute. The draft of a rectangle is presented on the screen at the begin of a test. Each correct response fills in a part of the rectangle with a solid scandalmongering coloring material, from left to right. Each incorrect reaction blanks the screen for 0.5 s. When the screen door returns, the tennessean is at the lapp point in the succession as before the incorrect response. The volunteer has to learn the correct sequence by test and error. When a sequence is correctly completed, the rectangle fills, the sieve blanks, and another empty rectangle reappears for the following test. A trial ends when the volunteer completes 15 right sequences. Each test consists of a new sequence that is randomly selected from a number of 32 different sequences. incorrect responses and time to complete each test are recorded.
Grammatical reasoning.
This 5-min test assesses language-based legitimate reasoning and has been used to assess the effects of assorted treatments on cognitive function ( 21 ). On each quiz, a coherent statement, such as “ A is preceded by B, ” is followed by the letters AB or BA. The volunteer decides whether each statement correctly describes the club of the two letters. The “ T ” key on the keyboard is pressed to indicate that a statement is true and the “ F ” key is pressed to indicate that a statement is false.
POMS questionnaire.
The POMS is a wide used, brief, standardize inventory of mood states ( 22 ). It is sensitive to a wide variety show of nutritional manipulations, environmental factors, sleep loss, and subclinical drug doses ( 14, 17 – 20, 23 ). The volunteers pace a serial of 65 mood-related adjectives on a five-point scale, in response to the doubt, “ How are you feeling right now ? ” The adjectives factor into six temper subscales ( tension-anxiety, depression-dejection, anger-hostility, vigor-activity, fatigue-inertia, and confusion-bewilderment ). A computerize adaptation of the POMS was administered during treadmill drill and during seated rest.
VAS.
To complete these scales, the participant placed a set on a 100-mm wrinkle between extreme answers at antonym ends of the cable. The extreme answers were “ very strong ( ly ) ” and “ not at all strong ( ly ). ” The questions were, “ How hard was the campaign required to complete these tests ?, ” and “ How hard did you have to concentrate to accomplish the tasks successfully ? ” Headache symptoms besides were evaluated at the end of each cognitive examination test by rating the statement, “ I have a headache. ”
Cognitive testing during exercise.
In summation to cognitive testing at rest, during each treadmill walking school term, three tests, the POMS, VAS, and PVT, were administered on a laptop calculator ( Sony, Vaio, model PCG-5G3L ) placed on a stationary platform suspended in presence of the participant while she walked at the ask footstep. Participants responded using a Razer DeathAdder mouse ( model RZ01–00150100-R3M1 ) with a 1-ms reaction time.
Statistical methods.
statistical analyses were performed using IBM SPSS Statistics v19.0. Due to variability in rate and extent of dehydration over the naturally of the DN and DD experiments, statistical comparisons for all dependent variables were conducted only when a unpaid attained a flat of dehydration ≥ 1 % body mass passing. A standard of 1 % was established, because this is the lowest level of dehydration that has been suggested as adequate to of altering cognitive function ( 1, 4, 5 ). Variability was expected, because dehydration was induced by moderate exercise in a moderate environment in the absence of hyperthermia. To determine whether levels of dehydration induced during DD trials compared to DN trials of ≥1 % body mass loss were different, a copulate triiodothyronine test was conducted comparing the exchange of plasma osmolality, a standard measure of hydration condition, of these conditions at the completion of testing. The addition in osmolality from the begin to end of the test day was closely identical in the DN ( 11 ± 9 mOsm/kg ) and DD ( 10 ± 6 mOsm/kg ; P = 0.58 ) trials. In addition, a CI-based comparison screen demonstrated that the little deviation in percentage body mass changes in DN ( −1.38 ± 0.20 % ) compared to DD ( −1.37 ± 0.17 % ) were equivalent ( < 0.2 % ; P = 0.93 ). consequently, data from the DN and DD conditions were pooled for analysis. Results from cognitive tests in which participants had ≥1.0 % consistency mass loss were combined, careless of whether the dehydration occurred in the DN or DD trial, and were compared using a mated samples thyroxine test to the mean of the correspond EU tests. This routine resulted in ≤25 data pairs. A P respect of ≤0.05 ( 2-tailed ) was the standard for significance. Values in the text are means ± SD.
Results
When participants reported for testing at 0800 hydrogen each day, there were no differences between treatment conditions in body mass, urine specific gravity, or self-reported rest duration ( table 1 ).
TABLE 1
Physiological variables .EU .≥1% .P value2 .Body mass, kg 63.0 ± 10.5 63.4 ± 10.5 0.13 Urine specific gravity 1.014 ± 0.009 1.012 ± 0.006 0.31 Previous night’s sleep, h 7.6 ± 0.9 7.7 ± 0.5 0.66 Physiological variables .EU .≥1% .P value2 .Body mass, kg 63.0 ± 10.5 63.4 ± 10.5 0.13 Urine specific gravity 1.014 ± 0.009 1.012 ± 0.006 0.31 Previous night’s sleep, h 7.6 ± 0.9 7.7 ± 0.5 0.66
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TABLE 1
Physiological variables .EU .≥1% .P value2 .Body mass, kg 63.0 ± 10.5 63.4 ± 10.5 0.13 Urine specific gravity 1.014 ± 0.009 1.012 ± 0.006 0.31 Previous night’s sleep, h 7.6 ± 0.9 7.7 ± 0.5 0.66 Physiological variables .EU .≥1% .P value2 .Body mass, kg 63.0 ± 10.5 63.4 ± 10.5 0.13 Urine specific gravity 1.014 ± 0.009 1.012 ± 0.006 0.31 Previous night’s sleep, h 7.6 ± 0.9 7.7 ± 0.5 0.66
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For the DN and DD trials that resulted in a ≥1 % weight unit loss, mean body mass decreased ( −1.36 ± 0.16 % ). For the EU experiments, the fluid substitution regimen was deemed successful, because body bulk declined very little ( −0.12 ± 0.05 % ) ; for our test participants, this difference was equivalent to 48 milliliter of water in a total soundbox water of 39.69 L ( 24 ). cognitive performance was for the most separate not affected by meek dehydration. There were no meaning changes in the scanning ocular watchfulness undertaking with one exception ( false alarms ), PVT, four-choice reaction time test, matching to sample, reprise skill, and grammatical argue undertaking ( table 2 ) at rest. The individual aspect altered on the scanning ocular watchfulness job was false alarm errors ( P = 0.02 ), which slightly increased in the dehydrate condition ( table 2 ). During exercise on the treadmill, performance on the PVT was not affected by dehydration ( table 3 ).
TABLE 2
Cognitive tests and their components .EU .≥1% .P value2 .Scanning visual vigilance Correct responses, n 16.9 ± 4.4 16.5 ± 3.9 0.66 Reaction time, s 0.96 ± 0.20 1.00 ± 0.18 0.31 False alarms, n 2.6 ± 1.9 3.5 ± 2.9 0.02 Psychomotor vigilance test Correct hits, n 71.1 ± 2.0 70.8 ± 1.5 0.51 Premature errors, n 1.5 ± 1.1 1.3 ± 0.8 0.49 Reaction time, s 0.33 ± 0.05 0.33 ± 0.03 0.74 Four-choice reaction time Reaction time, s 0.36 ± 0.05 0.36 ± 0.04 0.94 Incorrect responses, n 3.6 ± 3.7 3.2 ± 4.1 0.42 Time-out errors, n 0.10 ± 0.20 0.24 ± 0.56 0.24 Matching to sample Correct responses, n 8.2 ± 1.7 8.0 ± 1.3 0.57 Time-out errors, n 0.39 ± 0.61 0.61 ± 0.59 0.16 Reaction time, s 3.9 ± 1.0 3.7 ± 0.9 0.40 Repeated acquisition Incorrect responses, n 19.1 ± 4.6 19.0 ± 3.8 0.90 Time to complete, s 12.7 ± 3.8 12.0 ± 3.9 0.23 Grammatical reasoning Correct responses, n 29.8 ± 2.2 29.5 ± 1.5 0.44 Incorrect responses, n 2.2 ± 2.2 2.5 ± 1.5 0.45 No response, n 0.04 ± 0.20 0.05 ± 0.20 0.33 Reaction time, s 2.5 ± 0.8 2.6 ± 0.9 0.45 POMS Tension-anxiety 9.3 ± 3.5 10.4 ± 2.8 0.14 Depression-dejection 17.7 ± 3.7 18.7 ± 4.5 0.33 Anger-hostility 14.5 ± 3.3 15.6 ± 3.1 0.04 Vigor-activity −16.1 ± 4.7 −14.2 ± 2.4 0.03 Fatigue-inertia 14.6 ± 3.1 17.1 ± 2.5 0.003 Confusion-bewilderment 6.7 ± 2.6 7.7 ± 1.7 0.06 Total mood disturbance 46.6 ± 15.4 55.4 ± 15.1 0.01 VAS Task difficulty 1.9 ± 1.4 3.0 ± 1.5 0.004 Concentration 2.9 ± 2.1 4.2 ± 1.6 0.01 Headache 1.1 ± 1.8 2.3 ± 2.2 0.05 Cognitive tests and their components .EU .≥1% .P value2 .Scanning visual vigilance Correct responses, n 16.9 ± 4.4 16.5 ± 3.9 0.66 Reaction time, s 0.96 ± 0.20 1.00 ± 0.18 0.31 False alarms, n 2.6 ± 1.9 3.5 ± 2.9 0.02 Psychomotor vigilance test Correct hits, n 71.1 ± 2.0 70.8 ± 1.5 0.51 Premature errors, n 1.5 ± 1.1 1.3 ± 0.8 0.49 Reaction time, s 0.33 ± 0.05 0.33 ± 0.03 0.74 Four-choice reaction time Reaction time, s 0.36 ± 0.05 0.36 ± 0.04 0.94 Incorrect responses, n 3.6 ± 3.7 3.2 ± 4.1 0.42 Time-out errors, n 0.10 ± 0.20 0.24 ± 0.56 0.24 Matching to sample Correct responses, n 8.2 ± 1.7 8.0 ± 1.3 0.57 Time-out errors, n 0.39 ± 0.61 0.61 ± 0.59 0.16 Reaction time, s 3.9 ± 1.0 3.7 ± 0.9 0.40 Repeated acquisition Incorrect responses, n 19.1 ± 4.6 19.0 ± 3.8 0.90 Time to complete, s 12.7 ± 3.8 12.0 ± 3.9 0.23 Grammatical reasoning Correct responses, n 29.8 ± 2.2 29.5 ± 1.5 0.44 Incorrect responses, n 2.2 ± 2.2 2.5 ± 1.5 0.45 No response, n 0.04 ± 0.20 0.05 ± 0.20 0.33 Reaction time, s 2.5 ± 0.8 2.6 ± 0.9 0.45 POMS Tension-anxiety 9.3 ± 3.5 10.4 ± 2.8 0.14 Depression-dejection 17.7 ± 3.7 18.7 ± 4.5 0.33 Anger-hostility 14.5 ± 3.3 15.6 ± 3.1 0.04 Vigor-activity −16.1 ± 4.7 −14.2 ± 2.4 0.03 Fatigue-inertia 14.6 ± 3.1 17.1 ± 2.5 0.003 Confusion-bewilderment 6.7 ± 2.6 7.7 ± 1.7 0.06 Total mood disturbance 46.6 ± 15.4 55.4 ± 15.1 0.01 VAS Task difficulty 1.9 ± 1.4 3.0 ± 1.5 0.004 Concentration 2.9 ± 2.1 4.2 ± 1.6 0.01 Headache 1.1 ± 1.8 2.3 ± 2.2 0.05
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TABLE 2
Cognitive tests and their components .EU .≥1% .P value2 .Scanning visual vigilance Correct responses, n 16.9 ± 4.4 16.5 ± 3.9 0.66 Reaction time, s 0.96 ± 0.20 1.00 ± 0.18 0.31 False alarms, n 2.6 ± 1.9 3.5 ± 2.9 0.02 Psychomotor vigilance test Correct hits, n 71.1 ± 2.0 70.8 ± 1.5 0.51 Premature errors, n 1.5 ± 1.1 1.3 ± 0.8 0.49 Reaction time, s 0.33 ± 0.05 0.33 ± 0.03 0.74 Four-choice reaction time Reaction time, s 0.36 ± 0.05 0.36 ± 0.04 0.94 Incorrect responses, n 3.6 ± 3.7 3.2 ± 4.1 0.42 Time-out errors, n 0.10 ± 0.20 0.24 ± 0.56 0.24 Matching to sample Correct responses, n 8.2 ± 1.7 8.0 ± 1.3 0.57 Time-out errors, n 0.39 ± 0.61 0.61 ± 0.59 0.16 Reaction time, s 3.9 ± 1.0 3.7 ± 0.9 0.40 Repeated acquisition Incorrect responses, n 19.1 ± 4.6 19.0 ± 3.8 0.90 Time to complete, s 12.7 ± 3.8 12.0 ± 3.9 0.23 Grammatical reasoning Correct responses, n 29.8 ± 2.2 29.5 ± 1.5 0.44 Incorrect responses, n 2.2 ± 2.2 2.5 ± 1.5 0.45 No response, n 0.04 ± 0.20 0.05 ± 0.20 0.33 Reaction time, s 2.5 ± 0.8 2.6 ± 0.9 0.45 POMS Tension-anxiety 9.3 ± 3.5 10.4 ± 2.8 0.14 Depression-dejection 17.7 ± 3.7 18.7 ± 4.5 0.33 Anger-hostility 14.5 ± 3.3 15.6 ± 3.1 0.04 Vigor-activity −16.1 ± 4.7 −14.2 ± 2.4 0.03 Fatigue-inertia 14.6 ± 3.1 17.1 ± 2.5 0.003 Confusion-bewilderment 6.7 ± 2.6 7.7 ± 1.7 0.06 Total mood disturbance 46.6 ± 15.4 55.4 ± 15.1 0.01 VAS Task difficulty 1.9 ± 1.4 3.0 ± 1.5 0.004 Concentration 2.9 ± 2.1 4.2 ± 1.6 0.01 Headache 1.1 ± 1.8 2.3 ± 2.2 0.05 Cognitive tests and their components .EU .≥1% .P value2 .Scanning visual vigilance Correct responses, n 16.9 ± 4.4 16.5 ± 3.9 0.66 Reaction time, s 0.96 ± 0.20 1.00 ± 0.18 0.31 False alarms, n 2.6 ± 1.9 3.5 ± 2.9 0.02 Psychomotor vigilance test Correct hits, n 71.1 ± 2.0 70.8 ± 1.5 0.51 Premature errors, n 1.5 ± 1.1 1.3 ± 0.8 0.49 Reaction time, s 0.33 ± 0.05 0.33 ± 0.03 0.74 Four-choice reaction time Reaction time, s 0.36 ± 0.05 0.36 ± 0.04 0.94 Incorrect responses, n 3.6 ± 3.7 3.2 ± 4.1 0.42 Time-out errors, n 0.10 ± 0.20 0.24 ± 0.56 0.24 Matching to sample Correct responses, n 8.2 ± 1.7 8.0 ± 1.3 0.57 Time-out errors, n 0.39 ± 0.61 0.61 ± 0.59 0.16 Reaction time, s 3.9 ± 1.0 3.7 ± 0.9 0.40 Repeated acquisition Incorrect responses, n 19.1 ± 4.6 19.0 ± 3.8 0.90 Time to complete, s 12.7 ± 3.8 12.0 ± 3.9 0.23 Grammatical reasoning Correct responses, n 29.8 ± 2.2 29.5 ± 1.5 0.44 Incorrect responses, n 2.2 ± 2.2 2.5 ± 1.5 0.45 No response, n 0.04 ± 0.20 0.05 ± 0.20 0.33 Reaction time, s 2.5 ± 0.8 2.6 ± 0.9 0.45 POMS Tension-anxiety 9.3 ± 3.5 10.4 ± 2.8 0.14 Depression-dejection 17.7 ± 3.7 18.7 ± 4.5 0.33 Anger-hostility 14.5 ± 3.3 15.6 ± 3.1 0.04 Vigor-activity −16.1 ± 4.7 −14.2 ± 2.4 0.03 Fatigue-inertia 14.6 ± 3.1 17.1 ± 2.5 0.003 Confusion-bewilderment 6.7 ± 2.6 7.7 ± 1.7 0.06 Total mood disturbance 46.6 ± 15.4 55.4 ± 15.1 0.01 VAS Task difficulty 1.9 ± 1.4 3.0 ± 1.5 0.004 Concentration 2.9 ± 2.1 4.2 ± 1.6 0.01 Headache 1.1 ± 1.8 2.3 ± 2.2 0.05
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TABLE 3
Cognitive tests and their components .EU .≥1% .P value3 .Psychomotor vigilance test Correct hits, n 72.1 ± 1.4 72.0 ± 1.8 0.73 Premature errors, n 2.3 ± 1.9 2.8 ± 2.3 0.40 Reaction time, s 0.29 ± 0.03 0.29 ± 0.03 0.88 POMS Tension-anxiety 9.8 ± 3.3 11.2 ± 3.8 0.075 Depression-dejection 18.5 ± 4.4 19.9 ± 5.7 0.21 Anger-hostility 15.0 ± 4.4 16.4 ± 5.0 0.23 Vigor-activity −19.3 ± 5.5 −17.4 ± 3.7 0.04 Fatigue-inertia 13.3 ± 3.3 16.0 ± 4.9 0.003 Confusion-bewilderment 6.4 ± 2.2 7.5 ± 2.0 0.05 Total mood disturbance 43.7 ± 19.0 53.5 ± 20.8 0.04 VAS Task difficulty 1.9 ± 1.8 2.8 ± 1.7 0.03 Concentration 2.4 ± 2.1 3.6 ± 1.8 0.02 Headache 1.1 ± 1.7 2.2 ± 2.1 0.03 RPE 11.0 ± 2.0 11.3 ± 2.0 0.24 Pain rating 1.3 ± 1.1 1.4 ± 1.0 0.25 Cognitive tests and their components .EU .≥1% .P value3 .Psychomotor vigilance test Correct hits, n 72.1 ± 1.4 72.0 ± 1.8 0.73 Premature errors, n 2.3 ± 1.9 2.8 ± 2.3 0.40 Reaction time, s 0.29 ± 0.03 0.29 ± 0.03 0.88 POMS Tension-anxiety 9.8 ± 3.3 11.2 ± 3.8 0.075 Depression-dejection 18.5 ± 4.4 19.9 ± 5.7 0.21 Anger-hostility 15.0 ± 4.4 16.4 ± 5.0 0.23 Vigor-activity −19.3 ± 5.5 −17.4 ± 3.7 0.04 Fatigue-inertia 13.3 ± 3.3 16.0 ± 4.9 0.003 Confusion-bewilderment 6.4 ± 2.2 7.5 ± 2.0 0.05 Total mood disturbance 43.7 ± 19.0 53.5 ± 20.8 0.04 VAS Task difficulty 1.9 ± 1.8 2.8 ± 1.7 0.03 Concentration 2.4 ± 2.1 3.6 ± 1.8 0.02 Headache 1.1 ± 1.7 2.2 ± 2.1 0.03 RPE 11.0 ± 2.0 11.3 ± 2.0 0.24 Pain rating 1.3 ± 1.1 1.4 ± 1.0 0.25
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TABLE 3
Cognitive tests and their components .EU .≥1% .P value3 .Psychomotor vigilance test Correct hits, n 72.1 ± 1.4 72.0 ± 1.8 0.73 Premature errors, n 2.3 ± 1.9 2.8 ± 2.3 0.40 Reaction time, s 0.29 ± 0.03 0.29 ± 0.03 0.88 POMS Tension-anxiety 9.8 ± 3.3 11.2 ± 3.8 0.075 Depression-dejection 18.5 ± 4.4 19.9 ± 5.7 0.21 Anger-hostility 15.0 ± 4.4 16.4 ± 5.0 0.23 Vigor-activity −19.3 ± 5.5 −17.4 ± 3.7 0.04 Fatigue-inertia 13.3 ± 3.3 16.0 ± 4.9 0.003 Confusion-bewilderment 6.4 ± 2.2 7.5 ± 2.0 0.05 Total mood disturbance 43.7 ± 19.0 53.5 ± 20.8 0.04 VAS Task difficulty 1.9 ± 1.8 2.8 ± 1.7 0.03 Concentration 2.4 ± 2.1 3.6 ± 1.8 0.02 Headache 1.1 ± 1.7 2.2 ± 2.1 0.03 RPE 11.0 ± 2.0 11.3 ± 2.0 0.24 Pain rating 1.3 ± 1.1 1.4 ± 1.0 0.25 Cognitive tests and their components .EU .≥1% .P value3 .Psychomotor vigilance test Correct hits, n 72.1 ± 1.4 72.0 ± 1.8 0.73 Premature errors, n 2.3 ± 1.9 2.8 ± 2.3 0.40 Reaction time, s 0.29 ± 0.03 0.29 ± 0.03 0.88 POMS Tension-anxiety 9.8 ± 3.3 11.2 ± 3.8 0.075 Depression-dejection 18.5 ± 4.4 19.9 ± 5.7 0.21 Anger-hostility 15.0 ± 4.4 16.4 ± 5.0 0.23 Vigor-activity −19.3 ± 5.5 −17.4 ± 3.7 0.04 Fatigue-inertia 13.3 ± 3.3 16.0 ± 4.9 0.003 Confusion-bewilderment 6.4 ± 2.2 7.5 ± 2.0 0.05 Total mood disturbance 43.7 ± 19.0 53.5 ± 20.8 0.04 VAS Task difficulty 1.9 ± 1.8 2.8 ± 1.7 0.03 Concentration 2.4 ± 2.1 3.6 ± 1.8 0.02 Headache 1.1 ± 1.7 2.2 ± 2.1 0.03 RPE 11.0 ± 2.0 11.3 ± 2.0 0.24 Pain rating 1.3 ± 1.1 1.4 ± 1.0 0.25
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When testing was conducted on a desktop calculator at perch ( i.e., calm room that was adjacent to the environmental chamber, 23.0°C, dimly fall ), 3 of the 6 POMS subscales were adversely affected by dehydration. Participants reported increased anger-hostility ( P = 0.04 ) and fatigue-inertia ( P = 0.003 ) vitamin a well as a decrease in vigor-activity ( P = 0.03 ) ( postpone 2 ) when dehydrated. The aggregate measure of POMS ratings, the entire climate perturbation score besides deteriorated when women were dehydrated ( P = 0.01 ). The 3 VAS administered besides detected adverse effects of dehydration [ perceived task trouble ( P = 0.004 ) ; concentration ( P = 0.01 ) ; concern ( P = 0.05 ) ]. During use, adverse effects of dehydration on the POMS subscales and VAS besides were observed ( P ≤ 0.05 ) ( board 3 ). physiologic measurements revealed that post-exercise Tgi and center rate were greater ( P < 0.001 ) following meek dehydration ( ≥1 % ) ( table 4 ). Resting Tgi, immediately before cognitive examination administration was greater ( P = 0.004 ) when participants were mildly dehydrated. The change of plasma osmolality throughout the experimental day ( 0800 to 1750 planck's constant ) besides was greater during ≥1 % than during EU ( P = 0.006 ) ; however, plasma concentrations of lactate, glucose, and cortisol were alike across these experimental conditions ( Table 4 ).
TABLE 4
Physiological measurements .EU .≥1% .P value2 .Postexercise Tgi,3°C 37.8 ± 0.3 38.1 ± 0.2 <0.001 Postexercise heart rate,3bpm 152 ± 15 161 ± 15 <0.001 Resting Tgi,4°C 37.8 ± 0.4 38.1 ± 0.4 0.004 Resting plasma osmolality change,5mOsm/kg 3.5 ± 7.9 10.1 ± 6.1 0.006 Resting plasma lactate,5mmol/L 1.5 ± 0.9 1.2 ± 0.5 0.12 Resting plasma glucose,5mmol/L 4.8 ± 0.4 4.9 ± 0.3 0.15 Resting plasma cortisol,5nmol/L 92.7 ± 43.9 105.4 ± 39.2 0.11 Physiological measurements .EU .≥1% .P value2 .Postexercise Tgi,3°C 37.8 ± 0.3 38.1 ± 0.2 <0.001 Postexercise heart rate,3bpm 152 ± 15 161 ± 15 <0.001 Resting Tgi,4°C 37.8 ± 0.4 38.1 ± 0.4 0.004 Resting plasma osmolality change,5mOsm/kg 3.5 ± 7.9 10.1 ± 6.1 0.006 Resting plasma lactate,5mmol/L 1.5 ± 0.9 1.2 ± 0.5 0.12 Resting plasma glucose,5mmol/L 4.8 ± 0.4 4.9 ± 0.3 0.15 Resting plasma cortisol,5nmol/L 92.7 ± 43.9 105.4 ± 39.2 0.11 Open in new tab
TABLE 4
Physiological measurements .EU .≥1% .P value2 .Postexercise Tgi,3°C 37.8 ± 0.3 38.1 ± 0.2 <0.001 Postexercise heart rate,3bpm 152 ± 15 161 ± 15 <0.001 Resting Tgi,4°C 37.8 ± 0.4 38.1 ± 0.4 0.004 Resting plasma osmolality change,5mOsm/kg 3.5 ± 7.9 10.1 ± 6.1 0.006 Resting plasma lactate,5mmol/L 1.5 ± 0.9 1.2 ± 0.5 0.12 Resting plasma glucose,5mmol/L 4.8 ± 0.4 4.9 ± 0.3 0.15 Resting plasma cortisol,5nmol/L 92.7 ± 43.9 105.4 ± 39.2 0.11 Physiological measurements .EU .≥1% .P value2 .Postexercise Tgi,3°C 37.8 ± 0.3 38.1 ± 0.2 <0.001 Postexercise heart rate,3bpm 152 ± 15 161 ± 15 <0.001 Resting Tgi,4°C 37.8 ± 0.4 38.1 ± 0.4 0.004 Resting plasma osmolality change,5mOsm/kg 3.5 ± 7.9 10.1 ± 6.1 0.006 Resting plasma lactate,5mmol/L 1.5 ± 0.9 1.2 ± 0.5 0.12 Resting plasma glucose,5mmol/L 4.8 ± 0.4 4.9 ± 0.3 0.15 Resting plasma cortisol,5nmol/L 92.7 ± 43.9 105.4 ± 39.2 0.11 Open in new tab
Discussion
When female volunteers, at remainder or during drill, were dehydrated ( mean loss of 1.36 % body mass ), energy, fatigue, and aggregate climate, assessed by total mood affray score, were adversely affected. sensing of job difficulty and headache severity increased and ability to concentrate decreased when volunteers were dehydrated compared to their own EU ( dominance ) trials, at stay, and during exercise. performance on most aspects of cognitive serve assessed, including psychomotor watchfulness, chemical reaction time, working memory, and argue, was not affected during meek dehydration with the exception of a belittled increase in ocular watchfulness faithlessly alarm clock errors. Limited data are available on temper, cognitive performance, ability to concentrate, concern, and percept of undertaking difficulty when volunteers are at rest or actively exercising in a gently dehydrated country. This report demonstrates that, not alone at respite but besides during mince exercise, a across-the-board variety show of adverse changes occur in slightly dehydrated, young, healthy females. These may, in theory, interfere with motivation to continue exert or other activities. Our findings are consistent with a study conducted by Szinnai et alabama. ( 11 ) in which dehydration was induced by fluid limitation for 28 hydrogen, resulting in a intend dehydration tied of 2.6 % body aggregate loss. In that report, aspects of temper similar or identical to those we assessed were degraded, with fatigue increasing and alertness and perceived ability to concentrate declining. As in our discipline, the perceive feat necessity for tax skill increased with dehydration. cognitive performance was not affected in that survey, although some arouse differences in performance were noted ( 11 ). In addition to Szinnai et alabama. ( 11 ), other studies have not found significant changes in cognitive operation at dehydration levels < 2 % body batch loss including one we conducted in men ( 25, 26 ). Our discipline demonstrates that a wide variety show of climate states and symptoms are adversely affected at dehydration of 1.36 % body aggregate loss, which is well less than the 2.6 % induced by Szinnai et alabama. ( 11 ). In addition, we detected adverse effects in < 8 heat content and these effects were present when individuals were both exercising and resting. Information-processing when dehydrated during simulated sporting events has besides been investigated with exchangeable findings ( 6 – 8 ). During such events, dehydration ( −1 to −4 % body mass ) impairs temper, choice reaction clock time, and watchfulness. Although these studies assessed effects of mild-to-moderate dehydration on cognitive operation during simulated sporting events, they did not determine which aspects of cognitive operation are most affect, nor did they assess sensed attempt or symptoms of dehydration. The physiological mechanism ( s ) responsible for deterioration of temper and refer factors due to dehydration is not known. hypothalamic neurons detect dehydration ( 27 ) and may signal higher-order cortical brain regions regulating climate when initial physiologic indicators of dehydration look, resulting in adverse mood and symptoms. In humans, dehydration induced by thermal stress in the lapp range as this analyze modified fronto-parietal blood oxygen level-dependent response assessed by functional MRI without affecting cognitive performance ( 26 ). Given the critical physiological importance of maintaining hydration, adverse changes in climate and relate perceptions may serve as a signal that evolved to alert humans before more hard consequences occur, such as degradation in operation. once cognitive or physical operation is degraded, survival may be affected, because the ability to find water or answer to threats is diminished. This discipline has a issue of virtual implications. Although cognitive operation was not well impaired in healthy, young females who were mildly dehydrated, key climate states including energy, fatigue, perception of tax trouble, assiduity, and headache were adversely affected by a humble change in hydration. All these adverse effects were stage during respite and moderate exercise. therefore, at least in females, care of optimum hydration is substantive to ensure optimum temper and reduce symptoms, both at remainder and during tone down practice. Healthy females may lose lone 1.36 % of body batch during daily activities if they are not actively and regularly hydrate or are participating in use or sports, specially in a ardent or hot environment ( 28, 29 ). Females may besides be more readily affected by minor levels of dehydration during phases of the menstrual cycle that interrupt fluent balance and alter mood ( 30, 31 ). Changes in mood associated with premenstrual syndrome may be influenced by fluid shifts and the present data support this hypothesis ( 32 ). In summation, individuals at gamble of dehydration due to age, infirmity, or medical conditions associated with dehydration such as diabetes may experience adverse moods, increased perception of campaign, and concern when minimally dehydrated ( 33 – 35 ). The findings of the present investigation are improbable to result from confounding factors, such as an arithmetic mean of adverse effects of dehydration by volunteers or duration of photograph to exercise and stress, because these were cautiously controlled. Procedures were implemented to ensure that volunteers and investigators were unaware of each test condition, including an active dehydrate drug treatment and placebo, adenine well as administration of a minor bulk of mineral water in all experiments. During a poststudy consultation, volunteers could not identify examination conditions. The within-participant design compared a woman 's dehydrate behavioral data to her own hydrate experiment and controlled for the confuse effects of exert duration or fourth dimension of day. The effectiveness of the experimental manipulations to induce dehydration was confirmed by solid increases in plasma osmolality during dehydration ( table 4 ). Osmolality is a widely used physiological marker of hydration express in research studies and clinical settings ( 28, 36 ). however, other physiological changes due to mild dehydration ( Tgi change of 0.3°C, center rate deepen of 9 beats per minute ) ( mesa 4 ) were minimal, making it improbable that these factors affected climate ( 37 ). In stopping point, this discipline demonstrates that, in healthy young women, mild levels of dehydration solution in adverse changes in key mood states such as energy and fatigue duty deoxyadenosine monophosphate well as increased headaches and difficulty centralize, without substantially altering identify aspects of cognitive performance. future studies should determine the level of dehydration ( i.e., > 1.36 % aggregate loss ) at which cognitive performance initially is degraded in females and which aspects of cognition are most readily affected. We besides recommend that the effects of dehydration on cognition be examined in young men and at-risk populations such as children, aged individuals, and those with diabetes or stroke, because those medical conditions can result in dehydration ( 33 – 35, 38 ).
Acknowledgments
The authors thank Dr. Matthew Kramer and Christina E. Carvey for statistical aid and Lauren A. Thompson for technical aid with manuscript revision and submission. L.E.A., D.J.C., L.J., L.L.B., E.C., and H.R.L. designed research ; L.E.A., M.S.G., D.J.C., E.C.L., B.P.M., and J.F.K. conducted research ; L.E.A., M.S.G., E.C.L., and H.R.L. analyzed data ; and L.E.A., M.S.G., and H.R.L. wrote the manuscript and had primary province for its final examination content. All authors read and approved the final examination manuscript.
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. The hydration determine on the risk of stroke ( THIRST ) sketch. Neurocrit Care. 2009; 10: 187– 94.
Abbreviations
- doctor of divinity dehydration with diuretic drug discussion circumstance
- DN dehydration with no diuretic drug treatment condition
- european union euhydrated treatment circumstance
- pommy profile of Mood States
- PVT psychomotor watchfulness job
- rhesus factor relative humidity
- Tgi gastrointestinal temperature
- department of veterans affairs ocular analogue scale
Author notes
© 2012 American Society for Nutrition