Corey A. Peacock

The effect of three different energy drinks on oxygen consumption and perceived exertion during treadmill exercise

Methods Fifteen (22.1 ± 2.7 years old) participants completed the study. Maximal oxygen consumption (VO2 max) was initially measured to establish each participant’s exercise for the 70% treadmill exercise protocol after ingesting an energy drink. Following VO2 max testing, all participants completed a total of four conditions. Each condition required a participant to ingest an energy drink then rest in a seated position for one hour. Following one hour of rest, participants exercised for a total of 15 minutes on a treadmill at 70% of their VO2 max. For each condition, participants blindly ingested one of four price-matched beverages (12 oz. placebo (Squirt), 8.4 oz. Red Bull, 16 oz. Monster Energy , 2 oz. 5-hour ENERGY). Relative VO2 (ml.kg min) and RPE (6-20 Borg Scale) were recorded each minute during the treadmill exercise and averaged in five-minute increments and as an average for each 15-minute condition.

Comparing Acute Bouts of Sagittal Plane Progression Foam Rolling vs. Frontal Plane Progression Foam Rolling

Abstract Peacock, CA, Krein, DD, Antonio, J, Sanders, GJ, Silver, TA, and Colas, M. Comparing acute bouts of sagittal plane progression foam rolling vs. frontal plane progression foam rolling. J Strength Cond Res 29(8): 2310–2315, 2015—Many strength and conditioning professionals have included the use of foam rolling devices within a warm-up routine prior to both training and competition. Multiple studies have investigated foam rolling in regards to performance, flexibility, and rehabilitation; however, additional research is necessary in supporting the topic. Furthermore, as multiple foam rolling progressions exist, researching differences that may result from each is required. To investigate differences in foam rolling progressions, 16 athletically trained males underwent a 2-condition within-subjects protocol comparing the differences of 2 common foam rolling progressions in regards to performance testing. The 2 conditions included a foam rolling progression targeting the mediolateral axis of the body (FRml) and foam rolling progression targeting the anteroposterior axis (FRap). Each was administered in adjunct with a full-body dynamic warm-up. After each rolling progression, subjects performed National Football League combine drills, flexibility, and subjective scaling measures. The data demonstrated that FRml was effective at improving flexibility (p ⩽ 0.05) when compared with FRap. No other differences existed between progressions.

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 subjects tolerance to LBNP.

Effects of an Exercise Intervention on Body Composition in Older AdultMales Diagnosed with Parkinsons disease: A Brief Report

The investigation examined the value of a multifaceted exercise intervention on body composition and strength, in those diagnosed with Parkinson’s disease (PD). 8 males subjects diagnosed with PD (69.13 ± 6.20 years) completed a previously introduced, 8-week, 24-session exercise intervention. A repeated-measures analysis of variance (ANOVA) demonstrated improvements in body composition and muscular strength following the exercise intervention. The data suggests the multifaceted exercise intervention is an effective tool for improving strength and body composition in males diagnosed with PD.

Assessing a Monitoring Scale of Physiological Health and Risk Assessment Among Those Exposed to Heated Environments: A Brief Report

Background: Prevention of heat illness is of considerable medical interest within the field of occupational work. There are many established methods of perceptual health assessment; however, many are rather unpractical and timely. The objective was to improve the practicality and timeliness of perceptual physiological monitoring; a Heat Thermal Sensation scale has been developed. The usefulness of the scale was assessed on its ability to monitor physiological variable. Materials and Methods: Ten apparently healthy individuals performed physically exerting activity while exposed to 37 C. Sensation and physiology were measured throughout. Results: The perceptual monitoring scale demonstrated weak positive correlations with human physiological variables including cardiorespiratory stresses. It demonstrated no correlation with thermoregulation stress. Conclusion: The scale needs further development to better improve heat illness practices to those commonly exposed in extreme heat during occupational work.

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

IntroductionDehydration 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.PurposeThe 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.MethodsTen 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.ResultsDuring 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.ConclusionThe 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.

Bilateral Asymmetries in Ultrasound Assessments of the Rectus Femoris throughout an NCAA Division I Volleyball Preseason

The purpose of the study was to assess glycogen content of the rectus femoris (RF) muscles utilizing high-frequency ultrasound throughout an intensive, nine-day preseason training period in NCAA division I volleyball athletes. In the morning prior to the beginning of practice, athletes (n = 13) left and right RF muscles were assessed via ultrasound to quantify muscle fuel ratings (0–100 score range). The recommended location of the RF ultrasound scans were based on manufacturer guidelines, and the same technician recorded the daily measurements. To assess daily training load, session ratings of perceived exertion (s-RPE) were utilized. A paired t-test revealed a large significant difference between left (51.7 ± 17.9) and right (32.8 ± 17.4) RF muscle fuel ratings (p < 0.001). There was also a major effect of time on s-RPE (p < 0.001) and left (dominant) RF fuel rating (p = 0.001). s-RPE decreased from the beginning to the end of the training camp. However, left RF fuel ratings increased from the first to the second day, then remained elevated all throughout the preseason. In conclusion, all athletes were left-leg dominant and had a 57.6% bilateral asymmetry between their left and right RF muscle fuel ratings despite changes in training load. High-frequency ultrasounds are a noninvasive assessment tool that can determine glycogen replenishment asymmetries in the RF.

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.

The effects of heavy resistance training and a high protein diet (3.4g/kg/d) on body composition, exercise performance and indices of health in resistance-trained individuals - a follow-up investigation

Background The consumption of a high protein diet (> 4g/kg/d) in trained men and women who did not alter their training program has been previously shown to have no significant effect on body composition. Thus, the purpose of this investigation was to determine if a high protein diet in conjunction with a body part, split-routine heavy resistance training program would affect indices of body composition, performance and health.