Life Sciences Commons^™

Influences On Pulmonary And Muscular V’O2-Kinetics, Uwe Drescher, Uwe Hoffmann

International Journal of Exercise Science: Conference Proceedings

Introduction

Muscular and respiratory V’O2-kinetics are influenced by many factors. At cellular level muscular V’O2 (V’O2musc) is affected by O2-delivery and O2-consumption. Further, these factors can be divided into muscle perfusion, capillary density, enzyme activity, mitochondrial proliferation, muscle fiber composition and some more.

Focusing on the difference between V’O2resp and V’O2musc the venous blood volume, the venous O2-stores and the dynamics of cardiac output can be identified as influences. These influences result in a time delay and a distortion of V’O2resp. Usually exercise step responses are used for estimating V’O2resp-kinetics. But it has to be recognized, that V’O2resp may be …

Blood Volume Unloading Reduces Cerebral Blood Flow, Taylor Drury, Darren Warburton, Aaron Phillips, Shannon Bredin

International Journal of Exercise Science: Conference Proceedings

Introduction: Cerebral autoregulation (CA) has been understood for over 50 years to maintain constant cerebral blood flow (CBF) over a wide range of arterial blood pressures (60-150 mmHg), and blood volumes. The original work, which published this relationship, however, was derived from a limited number of studies focused primarily on clinical populations. Since that time, it has been applied to healthy individuals and is a mainstay of almost all physiology textbooks. Recent evidence, however, has suggested that CBF in healthy individuals is not independent of alterations in blood pressure and volume, indicating a possible absence of cerebral autoregulation. Lower body …

A Description Of Variability Of Pacing In Marathon Distance Running, Tom Haney Jr., John Mercer Dr.

International Journal of Exercise Science

The purpose of this study was twofold: 1) to describe variability of pacing during a marathon and 2) to determine if there is a relationship between variability of pacing and marathon performance. Publically available personal global positioning system profiles from two marathons (Race 1 n = 116, Race 2 n = 169) were downloaded (http://connect.garmin.com) for analysis. The coefficient of variation of velocity (Velcov) was calculated for each profile. Each profile was categorized as finishing in under 3.9 hours, between 3.9 and 4.6 hours, or longer than 4.6 hours. Linear and quadratic lines of best fit were computed to describe …

Low Flow-Mediated Constriction: Prevalence, Impact, And Physiological Determinant, Kristin L. Parkhurst, Michelle Harrison, Takashi Tarumi, Hsin-Fu Lin, Hirofumi Tanaka

International Journal of Exercise Science: Conference Proceedings

Flow-mediated dilation (FMD) is a surrogate marker for endothelial function. In the FMD procedure, arterial response during cuff inflation is not taken into consideration yet studies have demonstrated vasoconstriction, vasodilation, and no change in the brachial artery during cuff inflation. The term low flow-mediated constriction (L-FMC) has been introduced to describe the vasoconstriction that occurs in some individuals during inflation of the cuff. PURPOSE: To determine 1) if brachial artery response during cuff inflation differed in a population with varied coronary artery disease (CAD) risk factor profiles, 2) the impact of this response on the subsequent calculation of FMD, and …

Lipid Profiles Of American Collegiate Football Athletes In Response To Fall Preseason Camp, Dustin Joubert, Stephen F. Crouse, Jonathan M. Oliver, Steven E. Martin, Justin Dobson, Steven E. Riechman, J.P. Bramhall, John S. Green, David Weir, Jon Tanguay

International Journal of Exercise Science: Conference Proceedings

Recent studies show former football athletes, especially football linemen, to be at increased cardiovascular disease risk. However, the lipid profiles of American NCAA Football Bowl Subdivision (FBS) players in response to sport participation are currently unknown. PURPOSE: To quantify the effects of participation in fall preseason football training camp on the blood lipid profiles in NCAA FBS athletes. METHODS: Seated venous blood samples were drawn in the morning after an overnight fast from 51 football players (age = 20 ± 2 yr, weight = 232.8 ± 40.8 lb, height = 73.9 ± 2.6 in) and analyzed for total cholesterol (TC), …

Hemodynamics At Maximum Exercise And Exercise Recovery In Freshman Football Recruits At A Bcs School, Krystal Doughty, Steven Martin, Brad Lambert, Jon Oliver, David Wier, John Tanguay, Justin Dobson, Katie Mccammon, S.F Crouse Facsm, J.S. Green Facsm

International Journal of Exercise Science: Conference Proceedings

To determine if blood pressures assessed during max exercise and exercise recovery differ in Freshman football player recruits classified according to body mass index categories (BMICAT). A group of 107 freshman football recruits (mean age=18.2yrs, mean height=187.2 cm, mean weight = 103.0 kg, mean BMI=27.4 kg/meters squared, mean percent fat= 18.3%.) underwent graded exercise testing on a treadmill. Height and weight were assessed and BMI was calculated as weight (kg) / height (m) squared. All 97 subjects were classified as either “normal weight”(NW) (N=38), “overweight” (OW)(N=41) or “obese” (OB)(N=28) according to the National Institutes of Health guidelines. Body fat percentage …

Artificial Sweetener Sensing In The Human Mouth And Effect On Exercise Performance, James Mock

International Journal of Exercise Science: Conference Proceedings

Many studies have suggested that oral rinsing of a sweet carbohydrate can positively affect exercise performance by stimulating reward centers in the brain. However, few studies have been performed which compared the effects of a sweet carbohydrate with a sweet artificial sweetener. The purpose of this study was to examine the effects of a sweet carbohydrate rinse, an artificial sweetener rinse, and a water rinse on exercise performance. Eight college students completed a ten-minute trial ride and were able to perform significantly more work when rinsing with the carbohydrate or artificial sweetener rinses (Total work= 116.63 (20.3) kJ p=0.003, 117.04 …