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Natick, MA, United States

Emmanuel H.,University of Connecticut | Casa D.J.,University of Connecticut | Beasley K.N.,USARIEM | Lee E.C.,University of Connecticut | And 4 more authors.
Journal of Strength and Conditioning Research

Emmanuel, H, Casa, DJ, Beasley, KN, Lee, EC, McDermott, BP, Yamamoto, LM, Armstrong, LE, and Maresh, CM. Appearance of D2O in sweat after oral and oral-intravenous rehydration in men. J Strength Cond Res 25(8): 2092-2099, 2011-Intravenous (IV) rehydration is common in athletics, but its thermoregulatory benefits and ergogenicity have not been elucidated. Availability of orally ingested fluid is dependent on gastric emptying and intestinal absorption rate. Deuterium oxide (D2O) has been used to demonstrate that fluid ingested during exercise appears in sweat within 10 minutes. The purpose of this study was to determine the effect of concurrent IV rehydration on D2O appearance in sweat samples after per ora rehydration with D2O labeled fluid. We hypothesized that the combination method would not be superior to the oral method. Ten fit men (age 23 ± 4, V̇O2max 59.49 ± 4.09 L·min -1) underwent 20 hours of fluid restriction resulting in 1.95 ± 0.25% body weight loss before beginning treadmill exercise and cycling. Exercise was performed in an environmental chamber (35.6 ± 0.2°C, 35.0 ± 1.8% relative humidity) for 2 hours at 55% V̇O2max, and the participants exhibited a mean body weight deficit of 4.50 ± 0.04%. Thermoregulatory measures were recorded while subjects were rehydrated with oral (OR) or oral combined with intravenous (IVO) fluid traced with D 2O. After 30 minutes of rehydration and 30 minutes of seated recovery, the subjects began treadmill exercise at 55-60% V̇O 2max. Forehead sweat samples were collected 0, 5, 10, 20, and 75 minutes from the start of rehydration. The samples were analyzed for D 2O via isotope ratio mass spectrometry. D2O did not appear in the sweat within 20 minutes of rehydration; however, it did appear during the subsequent exercise bout. There was no significant difference between rehydration modes. Plasma volume increases and decreased volume of orally ingested fluid did not significantly alter transit time from ingestion to appearance in excreted sweat. The IVO method does not appear to be superior to the traditional OR method of rehydration. © 2011 National Strength and Conditioning Association. Source

Helfer B.S.,Lincoln Laboratory | Quatieri T.F.,Lincoln Laboratory | Williamson J.R.,Lincoln Laboratory | Keyes L.,Lincoln Laboratory | And 8 more authors.
Proceedings of the Annual Conference of the International Speech Communication Association, INTERSPEECH

Speech analysis has shown potential for identifying neurological impairment. With brain trauma, changes in brain structure or connectivity may result in changes in source, prosodic, or articulatory aspects of voice. In this work, we examine the articulatory components of speech reflected in formant tracks, and how changes in track dynamics and coordination map to cognitive decline. We address a population of athletes regularly receiving impacts to the head and showing signs of preclinical mild traumatic brain injury (mTBI), a state indicated by impaired cognitive performance occurring prior to concussion. We hypothesize that this preclinical damage results in 1) changes in average vocal tract dynamics measured by formant frequencies, their velocities, and acceleration, and 2) changes in articulatory coordination measured by a novel formant-frequency cross-correlation characterization. These features allow machine learning algorithms to detect preclinical mTBI identified by a battery of cognitive tests. A comparison is performed of the effectiveness of vocal tract dynamics features versus articulatory coordination features. This evaluation is done using receiver operating characteristic (ROC) curves along with confidence bounds. The articulatory dynamics features achieve area under the ROC curve (AUC) values between 0.72 and 0.98, whereas the articulatory coordination features achieve AUC values between 0.94 and 0.97. Copyright © 2014 ISCA. Source

Sharp M.A.,USARIEM | Hendrickson N.R.,USARIEM | Staab J.S.,USARIEM | Mcclung H.L.,USARIEM | And 2 more authors.
Journal of Strength and Conditioning Research

Sharp, MA, Hendrickson, NR, Staab, JS, McClung, HL, Nindl, BC, and Michniak-Kohn, BB. Effects of short-term quercetin supplementation on soldier performance. J Strength Cond Res 26(7): S53-S60, 2012 - The purpose was to assess the short-term effects of quercetin supplementation on aerobically demanding soldier performance. In a double-blind crossover study, 16 male soldiers performed 3 days of aerobically demanding exercise under 3 conditions: Baseline (B), Placebo (P), and Quercetin (Q). Day 1 was a treadmill V̇o 2peak test. Days 2 and 3 were identical, consisting of 75 minutes of loaded treadmill marching (LM) and a subsequent cycling time trial (TT) to complete 200 kJ of work. After B condition, the soldiers consumed 2 energy bars, each containing 0 mg (placebo) or 500 mg of quercetin (1,000 mg·d -1) for 8.5 days. Beginning day 6 of supplementation, the soldiers performed the 3 exercise days. There was a significant (p > 0.05) increase in plasma Q after Q supplementation. Repeated measures analyses of variance revealed no differences after P or Q supplementation as compared with B in V̇o 2peak (B = 48.9 ± 1.1, P = 49.3 ± 1.1, Q = 48.8 ± 1.2 ml·kg -1·min -1) or TT time (B = 18.4 ± 1.0, P = 18.5 ± 1.1, Q = 18.3 ± 1.0 minutes [mean day 1 and day 2]). The respiratory exchange ratio during LM did not differ across treatments (B = 0.87 ± 0.03, P = 0.87 ± 0.03, Q = 0.86 ± 0.04 [mean day 1 and day 2]). Ratings of perceived exertion were not affected by Q supplementation during the V̇o 2peak test, LM or TT. Supplementation of 1,000 mg·d -1 of quercetin for 8.5 days had no positive effect on aerobically demanding soldier performance. It is possible that a different dosing regimen, a combination of antioxidants or a different form of quercetin supplementation, may be needed to produce an increase in soldier performance. © 2012 National Strength and Conditioning Association. Source

Quatieri T.F.,Lincoln Laboratory | Williamson J.R.,Lincoln Laboratory | Smalt C.J.,Lincoln Laboratory | Patel T.,Lincoln Laboratory | And 10 more authors.
Proceedings of the Annual Conference of the International Speech Communication Association, INTERSPEECH

Early, accurate detection of cognitive load can help reduce risk of accidents and injuries, and inform intervention and rehabilitation in recovery. Thus, simple noninvasive biomarkers are desired for determining cognitive load under cognitively complex tasks. In this study, a novel set of vocal biomarkers are introduced for detecting different cognitive load conditions. Our vocal biomarkers use phoneme- and pseudosyllable-based measures, and articulatory and source coordination derived from cross-correlation and temporal coherence of formant and creakiness measures. A ~2-hour protocol was designed to induce cognitive load by stressing auditory working memory. This was done by repeatedly requiring the subject to recall a sentence while holding a number of digits in memory. We demonstrate the power of our speech features to discriminate between high and low load conditions. Using a database consisting of audio from 13 subjects, we apply classification models of cognitive load, showing a ~7% detection equal-error rate from features derived from 40 sentence utterances (~4 minutes of audio). Copyright © 2015 ISCA. Source

Bukhari A.,USARIEM | Roberts S.B.,Tufts University | Young A.J.,USARIEM | McGraw S.,USARIEM | And 2 more authors.
Military Medicine

Adult civilian dependents of active duty military personnel (ADMP) may play a central role in influencing the home food environment and the risk of overweight and obesity in American Warfighters and military families. However, there is no information on whether this group would be receptive to weight control programs. We conducted a survey to determine the level of interest of adult civilian dependents of ADMP in participating in a group weight control program. Subjects were a convenience sample of 191 adult civilian dependents of ADMP (94% women, 6% men) based in Massachusetts and aged 33.8 ± 8.4 years, body mass index 25.5 ± 5.5 kg/m2. Overall, there was a significant effect of body mass index on interest in program participation (p = 0.004). Eighty five percent of overweight participants and 100% of obese participants reported being Moderately Likely or Very Likely to participate in a provided weight control program. In overweight and obese survey respondents there was no significant effect of ADMP rank on interest in program participation (p = 0.34). These findings suggest that overweight and obese adult civilian dependents of ADMP may be very receptive targets for programs to control overweight and obesity in military families. © Association of Military Surgeons of the U.S. All rights reserved. Source

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