Tumor necrosis factor-α, TNF receptor, and soluble TNF receptor responses to aerobic exercise in the heat.

The purpose of this study was to evaluate the effects of aerobic exercise in the heat on circulating concentrations of tumor necrosis factor (TNF)-α, soluble TNF receptors (STNFR1&2), and surface expression of TNFR1&2 on monocyte subpopulations. Twelve recreationally active Caucasian men (24.4 ± 3.4 yrs.; 180.0 ± 6.8 cm; 81.5 ± 8.0 kg; 47.2 ± 4.8 mL·kg-1·min-1) completed an exercise protocol in three environmental conditions: high temperature/low humidity [HTLH; 35 °C, 20% relative humidity (RH)]; high temperature/moderate humidity (HTMH; 35 °C, 45%RH); and moderate temperature/moderate humidity (MTMH; 22 °C, 45%RH). Each protocol consisted of a 60-minute cycling trial at 60% VO2max, a 15-minute rest, and a time-to-exhaustion trial at 90% VO2max (TTE). Blood was sampled before (PRE), immediately after (POST) the 60-minute trial, immediately post-TTE (PTTE), and one-hour post-TTE (REC). Circulating TNF-α and STNFR1&2 were assayed. TNFR1&2 expression on monocyte subsets was measured by flow cytometry on a subset of participants (n = 8). TNF-α area under the curve with respect to increase (AUCi) was greater during HTMH compared to MTMH and HTLH. STNFR1 concentration was greater during HTMH compared to MTMH. With all trials combined, STNFR1 concentration increased from PRE to POST, PTTE, and REC. TNFR1 expression on non-classical monocytes was greater during HTMH compared to HTLH while TNFR2 expression was lower during HTLH compared to both MTMH and HTMH. Data suggest that exercise in the heat increases circulating TNF-α and STNFR1 concentration concomitantly. Furthermore, non-classical monocyte expression of TNFRs are impacted by temperature and humidity during exercise.

Investigating Effects of Cold Water Hand Immersion on Selective Attention in Normobaric Hypoxia.

This study investigated the effect of cold-water hand immersion on selective attention as measured by the Stroop Color Word Test in nomorbaric normoxia and hypoxia. Ten healthy men rested for 60 min, after which they immersed their non-dominant hand into 5 °C water for 15 min. The interference score of the Stroop Color Word Test and thermal sensation were measured at baseline in the final 5 min of resting and in the final 5 min of cold water hand immersion. The interference score was not influenced by hypoxia but was found to be significantly improved compared to resting in both conditions during cold water hand immersion. Selective attention improved during 15 min of cold-water hand immersion, with increased thermal sensations rated as "very cool" of the immersed arm. Cold-water hand immersion may be helpful in improving cognitive function in normoxia and normobaric hypoxia.

Cold-induced vasodilation responses before and after exercise in normobaric normoxia and hypoxia.

PURPOSE: Cold-induced vasodilation (CIVD) is known to protect humans against local cold injuries and improve manual dexterity. The current study examined the effects of metabolic heat production on cold-induced vasodilation responses in normobaric hypoxia and normoxia. METHODS: Ten participants immersed their non-dominant hand into 5 °C water for 15 min. Minimum finger temperature (Tmin), maximum finger temperature (Tmax), onset time, amplitude, and peak time were measured before and after exercise under normoxia (21% O2) and two levels of normobaric hypoxia (17% O2 and 13% O2). RESULTS: Neither Tmin nor amplitude was affected by hypoxia. However, Tmax was significantly decreased by hypoxia while reduction in onset time and peak time trended towards significance. Tmin, Tmax, and amplitude were significantly higher during post-exercise CIVD than pre-exercise CIVD. CONCLUSION: The CIVD response may be negatively affected by the introduction of hypoxia whereas metabolic heat production via exercise may counteract adverse effects of hypoxia and improve CIVD responses.

Intake of caffeine from all sources and reasons for use by college students.

BACKGROUND & AIMS: Caffeine intake in a convenience sample of U.S. college students (N = 1248) was surveyed at five geographically-dispersed United States (U.S.) universities. METHODS: Intake from coffee, tea, soft drinks, energy drinks, gums, and medications was assessed. Associations between caffeine intake and demographic variables including sex, age, race/ethnicity, family income, general health, exercise, weight variables and tobacco use were examined. Reasons for use of caffeine-containing products were assessed. RESULTS: Caffeine, in any form, was consumed by 92% of students in the past year. Mean daily caffeine consumption for all students, including non-consumers, was 159 mg/d with a mean intake of 173 mg/d among caffeine users. Coffee was the main source of caffeine intake in male (120 mg/d) and female (111 mg/d) consumers. Male and female students consumed 53 vs. 30 mg/d of caffeine in energy drinks, respectively, and 28% consumed energy drinks with alcohol on at least one occasion. Students provided multiple reasons for caffeine use including: to feel awake (79%); enjoy the taste (68%); the social aspects of consumption (39%); improve concentration (31%); increase physical energy (27%); improve mood (18%); and alleviate stress (9%). CONCLUSIONS: As in the general U.S. population, coffee is the primary source of caffeine intake among the college students surveyed. Energy drinks provide less than half of total daily caffeine intake but more than among the general population. Students, especially women, consume somewhat more caffeine than the general population of individuals aged 19-30 y but less than individuals aged 31-50 y.

Acute Mountain Sickness is Reduced Following 2 Days of Staging During Subsequent Ascent to 4300 m.

OBJECTIVE: To determine whether 2 days of staging at 2500-3500 m, combined with either high or low physical activity, reduces acute mountain sickness (AMS) during subsequent ascent to 4300 m. METHODS: Three independent groups of unacclimatized men and women were staged for 2 days at either 2500 m (n = 18), 3000 m (n = 16), or 3500 m (n = 15) before ascending and living for 2 days at 4300 m and compared with a control group that directly ascended to 4300 m (n = 12). All individuals departed to the staging altitudes or 4300 m after spending one night at 2000 m during which they breathed supplemental oxygen to simulate sea level conditions. Half in each group participated in ∼3 hours of daily physical activity while half were sedentary. Women accounted for ∼25% of each group. AMS incidence was assessed using the Environmental Symptoms Questionnaire. AMS was classified as mild (≥0.7 and <1.5), moderate (≥1.5 and <2.6), and severe (≥2.6). RESULTS: While staging, the incidence of AMS was lower (p < 0.001) in the 2500 m (0%), 3000 m (13%), and 3500 m (40%) staged groups than the direct ascent control group (83%). After ascent to 4300 m, the incidence of AMS was lower in the 3000 m (43%) and 3500 m (40%) groups than the 2500 m group (67%) and direct ascent control (83%). Neither activity level nor sex influenced the incidence of AMS during further ascent to 4300 m. CONCLUSIONS: Two days of staging at either 3000 or 3500 m, with or without physical activity, reduced AMS during subsequent ascent to 4300 m but staging at 3000 m may be recommended because of less incidence of AMS.

The effects of a 12-week worksite physical activity intervention on anthropometric indices, blood pressure indices, and plasma biomarkers of cardiovascular disease risk among university employees.

BACKGROUND: To determine the effectiveness of a low-cost 12-week worksite physical activity intervention targeting a goal of 10,000 steps per day on reducing anthropometric indices, blood pressure indices, and plasma biomarkers of cardiovascular disease (CVD) risk among the employees of a major university. METHODS: Fifty university employees (n = 43 female, n = 7 male; mean age = 48 ± 10 years) participated in the 12-week physical activity intervention (60 min, 3 day/week). Each session included both aerobic (cardiorespiratory endurance) and muscle-strengthening (resistance) physical activity using existing university facilities and equipment. Anthropometric indices, blood pressure indices, and plasma biomarkers of CVD risk assessed included those for obesity (body mass index), hypertension (systolic blood pressure, SBP; diastolic blood pressure, DBP), dyslipidemia (high-density lipoprotein, HDL; low-density lipoprotein, LDL; total serum cholesterol), and prediabetes (impaired fasting glucose, IFG). Steps per day were assessed using a wrist-worn activity monitor. Participants were given the goal of 10,000 steps per day and categorized as either compliers (≥ 10,000 steps per day on average) or non-compliers (< 10,000 steps per day on average) based on their ability to achieve this goal. RESULTS: Overall, 34% of participants at baseline were already at an elevated risk of CVD due to age. On average, 28% of participants adhered to the goal of 10,000 steps per day. After 12-weeks, participants in both groups (compliers and non-compliers) had lower BMI scores (p < 0.001), lower HDL scores (p < 0.034), and higher IFG scores (p < 0.001). The non-compliers had a greater reduction of BMI scores than the compliers (p = 0.003). Participants at risk for CVD had greater reductions than those not at risk for several risk factors, including SBP (p = 0.020), DBP (p = 0.028), IFG (p = 0.002), LDL (p = 0.006), and total serum cholesterol (p = 0.009). CONCLUSION: While the physical activity intervention showed mixed results overall with both favorable changes in anthropometric indices yet unfavorable changes in plasma biomarkers, it was particularly beneficial in regards to both blood pressure indices and plasma biomarkers among those already at risk of CVD. Trial registration ClinicalTrials.gov NCT03385447; retrospectively registered.

The Effect of Inspiratory Resistance on Exercise Performance and Perception in Moderate Normobaric Hypoxia.

Seo, Yongsuk, Jeremiah Vaughan, Tyler D. Quinn, Brittany Followay, Raymond Roberge, Ellen L. Glickman, and Jung-Hyun Kim. The effect of inspiratory resistance on exercise performance and perception in moderate normobaric hypoxia. High Alt Med Biol. 18:417-424, 2017. PURPOSE: Respirators are simple and efficient in protecting workers against toxic airborne substances; however, their use may limit the physical performance of workers. The purpose of this study was to determine the effect of inspiratory resistance on physical performance and breathing perception in normobaric hypoxia. METHOD: Nine healthy men wore a tight-fitting respiratory mask outfitted with one of four different inspiratory resistors (R) (0, 1.5, 4.5, 7.5 cm H2O/L/Sec) while exercising at normobaric hypoxia (17% O2) at submaximal exercise workloads of 50, 100, and 150 W on a cycle ergometer for 10 minutes each, followed by a maximal oxygen uptake (VO2max) test to exhaustion. RESULTS: Maximal power output at R7.5 was significantly lower than R0 (p = 0.016) and R1.5 (p = 0.035). Respiration rate was significantly reduced at R4.5 (p = 0.011) and R7.5 (p ≤ 0.001) compared with R0. Minute ventilation was significantly decreased in R7.5 compared with R0 (p = 0.003), R1.5 (p = 0.010), and R4.5 (p = 0.016), whereas VO2 was not significantly changed. Breathing comfort (BC) and breathing effort (BE) were significantly impaired in R7.5 (BC: p = 0.025, BE: p = 0.001) and R4.5 (BC: p = 0.007, BE: p = 0.001) compared with R0, but rating of perceived exertion (RPE) remained unchanged. CONCLUSIONS: Added inspiratory resistance limited maximal power output and increased perceptions of BC and BE in normobaric hypoxia. However, low-to-moderate inspiratory resistance did not have a deleterious effect on VO2 or RPE at submaximal or maximal exercise. Perceptual and physiological characteristics of respirators of varying inspiratory resistances should be considered by manufacturers and end users during design and respirator selection processes.

The Effect of Psychomotor Performance, Cerebral and Arterial Blood Saturation between African-American and Caucasian Males Before, During and After Normobaric Hypoxic Exercise.

To further elucidate physiological and cognitive performance differences between African-American (AA) and Caucasian individuals (CAU) before, during or after hypoxic and normoxic exercise. Twelve college aged (18-25) apparently healthy African-American (six volunteers) and Caucasian (six subjects) males took part in two trials consisting of normobaric normoxia and normobaric hypoxia (12% oxygen). Each subject cycled at 50% of their altitude adjusted VO2max (-26% of normoxia VO2max) for one hour after a two-hour baseline. Subjects were monitored for cerebral and arterial O2 saturation, as well as the Trail Making Test A and B (TMT) psychomotor performance. Arterial saturation proved to be significantly higher in AA (86.0±4.7) compared to CAU (79.5±4.8) during the first 60 minutes of exposure to hypoxia at rest (p=0.039), but not during exercise. However, cerebral oxygenation to the left frontal lobe was decreased near the conclusion and in 30 minutes after normoxic exercise. TMT B data revealed that CAU (79±12.7) had faster scores than the AA subjects (98±25.1) at all time points and was significantly different at the 115-minute time point of the hypoxic trial (p=0.024). The data suggests that before, during and after normobaric normoxia and hypoxia trial there is a differential response between AA and CAU in regards to arterial and cerebral oxygenation, as well as psychomotor tests.

Cerebral Hemodynamics and Executive Function During Exercise and Recovery in Normobaric Hypoxia.

BACKGROUND: Hypoxia and exercise each exhibit opposing effects on executive function, and the mechanisms for this are not entirely clear. This study examined the influence of cerebral oxygenation and perfusion on executive function during exercise and recovery in normobaric hypoxia (NH) and normoxia (N). METHODS: There were 18 subjects who completed cycling trials in NH (12.5% FIo2) and N (20.93% FIo2). Right prefrontal cortex (PFC) oxyhemoglobin (O2Hb) and middle cerebral artery blood velocity (MCAbv) were collected during executive function challenges [mathematical processing and running memory continuous performance task (RMCPT)] at baseline, following 30 min of acclimation, during 20 min of cycling (60% Vo2max), and at 1, 15, 30, and 45 min following exercise. RESULTS: Results indicated effects of time for Math, RMCPT, and O2Hb; but not for MCAbv. Results also indicated effects of condition for O2Hb. Math scores were improved by 8.0% during exercise and remained elevated at 30 min of recovery (12.5%), RMCPT scores significantly improved at all time points (7.5-11.9%), and O2Hb increased by 662.2% and 440.9% during exercise in N and NH, respectively, and remained elevated through 15 min of recovery in both conditions. DISCUSSION: These results support the influence of PFC oxygenation and perfusion on executive function during exercise and recovery in N and NH.Stavres J, Gerhart HD, Kim J-H, Glickman EL, Seo Y. Cerebral hemodynamics and executive function during exercise and recovery in normobaric hypoxia. Aerosp Med Hum Perform 2017; 88(10):911-917.

"Pokémon Go!" May Promote Walking, Discourage Sedentary Behavior in College Students.

OBJECTIVE: To assess self-reported walking and sedentary behavior in young adults before and after downloading "Pokémon Go!". MATERIALS AND METHODS: In September 2016, a sample of 358 (19.8 ± 2.1 years old, n = 187 females) college students who had downloaded "Pokémon Go!" on their cellular telephones (i.e., cell phones) were surveyed for weekly walking and sedentary behavior via the International Physical Activity Questionnaire. A single interview was administered to participants who estimated their walking and sedentary behavior at three time points: the week immediately preceding their download of "Pokémon Go!" (Baseline), the first week after downloading the game (Time 1), and the week the survey was completed (Time 2). Differences in self-reported physical activity and sedentary behavior across the three time points and across the two genders were compared via analyses of variance. RESULTS: There was a significant main effect of time (F ≥ 49.3, P ≤ 0.001) for walking and sedentary behavior. Participants reported greater (t ≥ 9.5, P < 0.001) daily walking during Time 1 (218.6 ± 156.3 minutes) and Time 2 (182.7 ± 172.1 minutes) versus the baseline (108.5 ± 110.8 minutes). Walking behavior was also significantly greater (t = 4.1, P < 0.001) at Time 1 versus Time 2. Participants reported greater (t ≥ 6.5, P < 0.001) daily sedentary behavior during baseline (346.6 ± 201.3 minutes) versus both Time 1 (261.7 ± 172.4 minutes) and Time 2 (284.3 ± 175.4 minutes). Sedentary behavior was also significantly greater (t = 2.6, P = 0.03) at Time 2 versus Time 1. There were no effects of gender (F ≤ 1.8, P ≥ 0.17). CONCLUSION: Playing "Pokémon Go!" was associated with increased self-reported walking and decreased sedentary behavior. Such games hold promise as technology that may promote physical activity and discourage sedentary behavior.

Normobaric Hypoxia and Submaximal Exercise Effects on Running Memory and Mood State in Women.

BACKGROUND: An acute bout of exercise can improve cognitive function in normoxic and hypoxic conditions. However, limited research supports the improvement of cognitive function and mood state in women. The purpose of this study was to examine the effects of hypoxia and exercise on working memory and mood state in women. METHODS: There were 15 healthy women (age = 22 ± 2 yr) who completed the Automated Neuropsychological Assessment Metrics-4th Edition (ANAM), including the Running Memory Continuous Performance Task (RMCPT) and Total Mood Disturbance (TMD) in normoxia (21% O2), at rest in normoxia and hypoxia (12.5% O2), and during cycling exercise at 60% and 40% Vo2max in hypoxia. RESULTS: RMCPT was not significantly impaired at 30 (100.3 ± 17.2) and 60 (96.6 ± 17.3) min rest in hypoxia compared to baseline in normoxia (97.0 ± 17.0). However, RMCPT was significantly improved during exercise (106.7 ± 20.8) at 60% Vo2max compared to 60 min rest in hypoxia. Following 30 (-89.4 ± 48.3) and 60 min of exposure to hypoxia (-79.8 ± 55.9) at rest, TMD was impaired compared with baseline (-107.1 ± 46.2). TMD was significantly improved during exercise (-108.5 ± 42.7) at 40% Vo2max compared with 30 min rest in hypoxia. Also, RMCPT was significantly improved during exercise (104.0 ± 19.1) at 60% Vo2max compared to 60 min rest in hypoxia (96.6 ± 17.3). DISCUSSION: Hypoxia and an acute bout of exercise partially influence RMCPT and TMD. Furthermore, a moderate-intensity bout of exercise (60%) may be a more potent stimulant for improving cognitive function than low-intensity (40%) exercise. The present data should be considered by aeromedical personnel performing cognitive tasks in hypoxia.Seo Y, Gerhart HD, Stavres J, Fennell C, Draper S, Glickman EL. Normobaric hypoxia and submaximal exercise effects on running memory and mood state in women. Aerosp Med Hum Perform. 2017; 88(7):627-632.

Does Acute Normobaric Hypoxia Induce Anapyrexia in Adult Humans?

Seo, Yongsuk, Hayden D. Gerhart, Jeremiah Vaughan, Jung-Hyun Kim, and Ellen L. Glickman. Does acute normobaric hypoxia induce anapyrexia in adult humans? High Alt Med Biol. 18:185-190, 2017.-Exposure to hypoxia is known to induce a reduction in core body temperature as a protective mechanism, which has been shown in both animals and humans. The purpose of this study was to test if acute exposure to normobaric hypoxia (NH) induces anapyrexia in adult humans in association with decreased peripheral oxygen saturation (SpO2). Ten healthy male subjects were seated in atmospheres of normobaric normoxia 21% (NN21), NH 17% (NH17), and 13% (NH13) O2 for 60 minutes in a counterbalanced manner. Rectal temperature (Tre) was continuously monitored together with the quantification of metabolic heat production (MHP) and body heat storage (S). Baseline physiological measurements showed no differences between the three conditions. SpO2 was significantly decreased in NH17 and NH13 compared with NN21 (p ≤ 0.001). Tre decreased following 60 minutes of resting in all conditions, but, independent of the conditions, showed no association between Tre and levels of hypoxic SpO2. There was also no significant difference in either MHP or S between conditions. The present results showed no evidence of hypoxia-induced anapyrexia in adult humans during 1 hour of resting after exposure to NH either at 13% or 17% O2.

Pilot physiology, cognition and flight performance during flight simulation exposed to a 3810-m hypoxic condition.

BACKGROUND: Hypoxia is a physiological state defined as a reduction in the distribution of oxygen to the tissues of the body. It has been considered a major factor in aviation safety worldwide because of its potential for pilot disorientation. Pilots are able to operate aircrafts up to 3810 m without the use of supplemental oxygen and may exhibit symptoms associated with hypoxia. OBJECTIVE: To determine the effects of 3810 m on physiology, cognition and performance in pilots during a flight simulation. METHODS: Ten healthy male pilots engaged in a counterbalanced experimental protocol comparing a 0-m normoxic condition (NORM) with a 3810-m hypoxic condition (HYP) on pilot physiology, cognition and flight performance. RESULTS: Repeated-measures analysis of variance demonstrated a significant (p ≤ 0.05) time by condition interaction for physiological and cognitive alterations during HYP. A paired-samples t test demonstrated no differences in pilot performance (p ≥ 0.05) between conditions. CONCLUSION: Pilots exhibited physiological and cognitive impairments; however, pilot performance was not affected by HYP.

Combined incentives versus no-incentive exercise programs on objectively measured physical activity and health-related variables.

UNLABELLED: Incentivized exercise program interventions have recently led to mixed findings with regard to increasing physical activity, attendance, and improving healthy lifestyles. However, in this area limited research exists on implementing a combined negative reinforcement strategy, using a "buy-in" and positive reinforcement system. PURPOSE: To determine the effect of comparing a non-incentivized reward system with an incentivized reward system using combined positive and negative rewards on physical activity, attendance, and health and performance outcomes. METHODS: 15 Previously sedentary faculty and staff of a large public research university participated in two separate 12-week exercise interventions and wore a program accelerometer throughout the entire day during the 12weeks. During the first intervention, there were no incentives offered to participants. The second intervention consisted of an incentivized program. Positive reinforcements included various rewards for meeting achievements related to physical activity levels. A program rebate worth $25 for achieving 450miles was used as the negative reinforcement "buy-in" incentive. RESULTS: A two-way repeated measures ANOVA demonstrated a main effect of time for percent body fat (p<0.001) and push-ups (p=0.018). All other variables revealed no differences between conditions or from pre to post testing. There was no difference between conditions with physical activity or attendance. CONCLUSION: No differences in physical activity or health-related variables were found within the incentivized and non-incentivized conditions.

Low intensity exercise does not impact cognitive function during exposure to normobaric hypoxia.

Exposure to hypoxia is associated with cognitive impairment, mediated by cerebral deoxygenation. This can be problematic for individuals who perform mental tasks at high altitude. Eight healthy men completed two experimental trials consisting of 5h of exposure to normobaric hypoxia (12.5% O2). In one of the experimental trials (Hypoxia) subjects remained resting in a seated position the entire 5h; in the other experimental trial (Hypoxia and Exercise) subjects rested 2h, cycled for 1h at constant wattage (workload equivalent to 50% of altitude adjusted VO2max), then rested the last 2h. Cerebral oxygenation was measured continuously via near-infrared spectroscopy and cognitive performance was assessed by Trail Making Test A and B. Cerebral oxygenation and cognitive performance both were impaired during exposure to hypoxia. In the Hypoxia and Exercise trial, subjects experienced further declinations in cerebral oxygenation without concomitant decreases in cognitive function. These data demonstrate that cognitive function declines during exposure to normobaric hypoxia and this decline is not exacerbated by low intensity exercise.

The effects of cold and lower body negative pressure on cardiovascular homeostasis.

PURPOSE: The purpose of this study is to determine how cold exposure and lower body negative pressure effected cardiovascular variables. METHODS: Eleven males (20.3 years ± 2.7) underwent two 20-minute exposures to LBNP. During the 2 trials, the subjects were exposed to cold air (10°C) (COLD) and to ambient temperature (23°C) (AMB). The trials consisted of a 100-minute pre-LBNP period followed by a 20-minute exposure to LBNP and then a 15-minute recovery period. Cardiovascular variables were recorded every 30 minutes using bioimpedance. RESULTS: When LBNP was applied during the AMB trials, stroke volume immediately decreased. During the COLD trial, there was a five-minute delay before the decrease in stroke volume. Heart rate increased immediately after LBNP initiation during the AMB trials but there was a delay in the increase during the COLD trials. That same pattern was followed with mean arterial blood pressures. Cerebral oxygenation was significantly lower throughout the COLD trial as compared to the AMB trials. Six subjects reported symptoms of syncope or presyncope during the AMB trials but there were no reports of symptoms during the COLD trials. CONCLUSION: From analysis of this data, cold improved the subject's tolerance to LBNP.

The Effects of a 12-Week Faculty and Staff Exercise Program on Health-Related Variables in a University Setting.

The obesity epidemic has grown in the past decade due to physical inactivity (i.e., having a sedentary job) and an increase in caloric intake. This problem combined with the reluctance of many faculty and staff members exercising in the same environment as student's presents a unique challenge in an academic setting. The purpose of this study was to examine the effectiveness of a 12-week exercise program focused toward the faculty and staff in improving several health-related variables such as curl-ups, push-ups, sit-and-reach, and balance. Fifty-seven faculty and staff participated in the current study. Participants engaged in a variety of exercise classes taught by certified instructors three days a week for 12-weeks. Paired samples t-tests illustrated a significant (p < 0.001) decrease in body mass and significant (p ≤ 0.001) improvements in curl-ups, push-ups, sit-and-reach, and balance. This data demonstrates that a 12-week faculty and staff exercise program has the potential to improve performance in several health-related variables such as curl-ups, push-ups, sit-and-reach, and balance. The ability of this program to improve health-related variables and possibly delay or prevent the development of overweight and/or obesity, sarcopenia, and other chronic diseases is encouraging.

Patterns of dietary supplement use among college students.

BACKGROUND & AIMS: Dietary supplements (DS) are popular in many countries but little data are available on their use by sub-populations such as college students. Since students share a variety of characteristics and similar lifestyles, their DS use may differ from the general population. This study assessed DS use, factors associated with DS use, and reasons for use among U.S. college students. METHODS: College students (N = 1248) at 5 U.S. universities were surveyed. Survey questions included descriptive demographics, types and frequency of DS used, reasons for use and money spent on supplements. Supplements were classified using standard criteria. Logistic regression analyses examined relationships between demographic and lifestyle factors and DS use. RESULTS: Sixty-six percent of college students surveyed used DS at least once a week, while 12% consumed 5 or more supplements a week. Forty-two percent used multivitamins/multiminerals, 18% vitamin C, 17% protein/amino acids and 13% calcium at least once a week. Factors associated with supplement use included dietary patterns, exercise, and tobacco use. Students used supplements to promote general health (73%), provide more energy (29%), increase muscle strength (20%), and enhance performance (19%). CONCLUSIONS: College students appear more likely to use DS than the general population and many use multiple types of supplements weekly. Habits established at a young age persist throughout life. Therefore, longitudinal research should be conducted to determine whether patterns of DS use established early in adulthood are maintained throughout life. Adequate scientific justification for widespread use of DS in healthy, young populations is lacking.

Do glucose containing beverages play a role in thermoregulation, thermal sensation, and mood state?

INTRODUCTION: Dehydration limits the appropriate delivery of oxygen and substrates to the working muscle. Further, the brain's ability to function may also be compromised whereby thermal sensation and mood state may be altered. PURPOSE: The purpose of the present investigation was to compare the thermoregulatory, perceptual, and negative mood state profile in glucose (GLU) vs. non-glucose beverage (NON-GLU) condition. METHODS: Ten healthy men volunteered and were counterbalanced either a GLU or NON-GLU containing beverage on separate mornings. In each condition, they were exposed to 37°C, 50% relative humidity (RH) for baseline, exercise, rehydration, and recovery periods. The exercise period elicited the desired level of dehydration (mean of 2.6 ± 0.3% body weight losses). Upon completion of the protracted exercise, participants were administered either a GLU or NON-GLU containing electrolyte based sports drink ad libitum for 30 min, followed by a recovery period of 15 min in 37°C, 50% RH. Rectal (Tre) and mean skin temperatures (Tsk) were continuously monitored. Gagge (TS) and heated thermal sensation (HTS), profile of mood state (POMS) were measure at the end of each period. RESULTS: During recovery after rehydration, Tre was not significantly different between conditions (GLU vs. NON-GLU) (37.4 ± 0.8 vs. 37.0 ± 1.2°C); Tsk was also not affected by rehydration in both conditions (36.0 ± 0.5 vs. 36.0 ± 0.6°C) and, TS and HTS did not differ between conditions (0.9 ± 1.3 vs.1.3 ± 0.7) and (1.0 ± 0.8 vs.0.8 ± 0.3). Total mood disturbance (TMD) score for the POMS was utilized for overall negative mood state and demonstrated a main effect for time (p < 0.05). TMD during recovery was decreased compared to before hydration in both conditions. CONCLUSION: The non-glucose containing beverage maintained plasma volume and was effective at maintaining body temperature homeostasis in a similar fashion compared to the glucose containing beverage. Furthermore, negative mood state was not different between the two conditions. The non-glucose beverages can serve a valuable role in the exercise environment depending upon the sport, the ambient temperature, the individual, duration of the exercise, the age and training states of the individual.