Sports Sciences Commons^™

The Effects Of Two Post-Activation Potentiation Methods On Muscular Activation, Ileana A. Jarquin, Samuel Montalvo, Daniel Conde, Gabriel Ibarra-Mejia, Sandor Dorgo

International Journal of Exercise Science: Conference Proceedings

Post Activation Potentiation (PAP) is an exercise concept based on utilizing a maximal voluntary contraction of the muscles at task to potentiate a dynamic muscular contraction of the same muscles. It is well established that PAP is modulated between performance readiness and muscular fatigue. Heart Rate percentage (HR%) has been used as an indicator of performance readiness and muscular fatigue. PURPOSE: To examine different muscular activation (μV) in response to two different PAP protocols during the vertical jump exercise. METHODS: 8 participants (5 males and 3 females; mean ± SD: Age = 22.6 ± 1.76 years; Height …

Exercise Cerebral Blood Flow Hemodynamics Differ In Hot Dry And Humid Conditions, Julianna J. Kilpatrick, Paolo Miguel Salvador, Kyleigh Allie, Eric Rivas

International Journal of Exercise Science: Conference Proceedings

Passive and exercise-heat stress have been reported to cause reductions in cerebral blood flow (CBF); however, it is unknown if CBF velocity is different under hot dry and humid conditions. PURPOSE: This project tested the hypothesis that upright rest and exercise-heat stress in hot dry and humid conditions result in similar CBF reductions. METHODS: Seven healthy active (7 day activity: 9887±3564 steps/day; VO₂max: 52±10 mL/kg/min) subjects (5M/2F, 24±9y, 171±6cm, 68±7kg) completed a 30 min baseline rest followed by 60 min of exercise at a rate of perceived exertion (RPE) of 12 (between light and somewhat hard) on a …

Similarities In Vasoconstrictor Responsiveness To Exogenous Norepinephrine In The Cutaneous Circulation Between Young Black And White Men, Rauchelle E. Richey, John Akins, Jeremiah Campbell, Guillermo Olvera, Zachary Martin, R Matthew Brothers

International Journal of Exercise Science: Conference Proceedings

Black (BL) men have an increased risk of hypertension and CVD compared to white (WH) men which is partially related to vascular dysfunction. In particular, elevated vascular resistance and increased sympathetic vascular transduction (SVT; greater constrictor and blood pressure responses for a burst of sympathetic nerve activity) may be a contributing factor. Previous reports indicate that BL men have exaggerated responses to a variety of stressors including cold pressor, orthostasis, and exercise; while also exhibiting increased SVT at rest. Additionally, rodent models indicate that oxidative stress contributes to heightened SVT. For example, hypertensive rats have elevated SVT which is attenuated …

Impact Of Time Restricted Feeding On Markers Of Cardiometabolic Health, Liliana I. Renteria, Elias Villalobos, Hunter S. Waldman, Matthew J. Mcallister

International Journal of Exercise Science: Conference Proceedings

Time restricted feeding (TRF) is a form of intermittent fasting in which all calories are consumed within a certain amount of time (i.e. 6-8 hrs) only water is ingested for the remainder of the day. Previous research shows improvements in body composition and some markers of cardiometabolic health, but it is not clear if these results were due to the decreased eating window, or due to a decrease in caloric intake that typically occurs with fasting protocols. PURPOSE: to assess whether a caloric deficit is necessary to achieve improvements in cardiometabolic health as well as evaluate the impact TRF has …

The Effect Of Neuromuscular Electrical Stimulation On Metabolic Changes In A Sedentary Population: A Pilot Study, Michelle Galvan, Jasmin Jenkins, Sudip Bajpeyi

International Journal of Exercise Science: Conference Proceedings

The Centers for Disease Control and Prevention (2015) declared that 80% of U.S. adults do not meet exercise recommendations by ACSM. Skeletal muscle contraction has been shown to increase mitochondrial content (energy production) and glucose uptake (decreased insulin resistance). Neuromuscular Electrical Stimulation (NMES) utilizes electrical impulses to induce muscle contractions and can be used as an alternate strategy to induce muscle contraction in sedentary adults. However, it is not clear if NMES induced muscle contraction may improve insulin sensitivity and metabolic health. PURPOSE: The purpose of this study was to investigate the effects of two weeks of NMES on …

The Effects Of Combined Exercise Training On Flow-Mediated Dilation And C-Reactive Protein In Overweight, Postmenopausal Women, Carmen A. Cook, Andreas Kreutzer, Michael M. Levitt, Maria A. Cardenas, Gail Teagle, Kirby Thames, Dennis J. Cheek, Melody D. Phillips

International Journal of Exercise Science: Conference Proceedings

Obesity-related inflammation, especially coupled with a decline in estrogen post menopause, leads to endothelial dysfunction where the endothelium is unable to adequately dilate in response to sheer stress. C-Reactive Protein (CRP) may cause endothelial dysfunction through superoxide production and downregulation of endothelial nitric oxide synthase leading to decreased nitric oxide production. Exercise training improves endothelial function through adaptations to increase nitric oxide bioavailability and regulation of superoxide production. PURPOSE: To determine the influence of acute and chronic combined resistance and aerobic exercise on flow-mediated dilation (FMD) and CRP in overweight to obese, postmenopausal women, as well as determining potential …

Transcranial Direct Current Stimulation Of Motor Cortex Enhances Running Performance., Seung-Bo Park, Dong Jun Sung, Bokyung Kim, Sojung Kim, Joung-Kyue Han

College of Science & Mathematics Departmental Research

Transcranial direct current stimulation (tDCS) is a technique used to modulate neuronal excitability through non-invasive brain stimulation that can enhance exercise performance. We hypothesize that tDCS would improve submaximal running time to exhaustion (TTE) and delay the increase in the rating of perceived exertion (RPE) over time. We also hypothesize that tDCS would not lead to difference in cardiorespiratory responses. We employed a randomized, single-blinded, and counterbalanced design in which 10 trained men participated. After receiving either 20 min of 1.98 mA anodal tDCS applied over the primary motor cortex (M1) or sham-operated control on separate days, participants completed a …

Pacing Strategies In The 200 Yard Freestyle By Collegiate Men, Peter Robinson, Scott P. Mclean

International Journal of Exercise Science: Conference Proceedings

ABSTRACT

Examination of components of a 200 yd freestyle race may provide useful information for understanding how pacing strategy contributes to successful performance. PURPOSE: To compare 50-yd splits of a 200-yd freestyle race in higher performing and lower performing swimmers to assess if pacing strategy differs between groups. METHODS: An ex post facto design was used employed to create a dataset of 200 yd freestyle results. Split times were generated for each 50 yard segment of a 200 yd race for two performance groups of swimmers; the first and last four finalists in eight conference championships each for NCAA Division …

A Family History Of Type 2 Diabetes Does Not Impact Skeletal Muscle Lipid Content, Jasmin Jenkins, Sudip Bajpeyi

International Journal of Exercise Science: Conference Proceedings

A high intramyocellular lipid (IMCL) has been associated not only with insulin resistance, obesity, and type 2 diabetes; but also in insulin sensitive endurance trained athletes – known as “athlete’s paradox”. A family history of type 2 diabetes (FH+) has been shown as a risk factor for the development of insulin resistance and type 2 diabetes (T2D). However, it is unclear whether a FH+ affects IMCL content and exercise induced changes in IMCL when compared to those without a family history of type 2 diabetes (FH-). PURPOSE: The purpose of this study were 1) to compare IMCL content between …

Walking With Leg Blood Flow Restriction: Wide-Rigid Cuffs Vs. Narrow-Elastic Bands, Sten Stray-Gundersen, Savannah V. Wooten, Hirofumi Tanaka

International Journal of Exercise Science: Conference Proceedings

Blood flow restriction (BFR) training has become a popular form of exercise in recent years. The concept is that light-load exercise with BFR elicits similar adaptations achieved with heavy-load exercise. Walking exercise in combination with pressurized wide-rigid (WR) cuffs has been shown to elicit higher cardiac workload and a vascular dysfunction due presumably to reperfusion injury to the endothelium. In contrast, narrow-elastic (NE) BFR bands may elicit different hemodynamic effects, as the limb is able to increase in diameter with increased blood flow accompanying exercise. PURPOSE: To compare two distinct forms of BFR bands during light-intensity exercise on cardiovascular …

Attenuated Pulsatile Load During Metaboreflex Activation Is Associated With Excess Adiposity In Dynapenic Postmenopausal Women, Arun Maharaj, Salvador Jaime, Stephen Fischer, Arturo Figueroa

International Journal of Exercise Science: Conference Proceedings

The age-related loss in muscle strength (dynapenia) is associated with elevated blood pressure (BP) and fat mass (FM). Aortic pulse pressure (PP), rather than brachial PP, more closely relates to cardiovascular events because it represents left ventricular pulsatile load, which is particularly important in older women. Purpose: To examine the impact of dynapenia and adiposity on aortic BP responses to metaboreflex activation (post-exercise muscle ischemia, PEMI) in postmenopausal women. Methods: 71 postmenopausal women [(dynapenic, n=41, 57±1 years), (non-dynapenic, n=30, 59±1 years)] were included in this study. FM, percent body fat (BF%) and percent lean mass (LM%) were measured using Dual …

Lower Leg Lean Mass Is Associated With Reduced Pulse Pressure Amplification In Postmenopausal Women, Stephen M. Fischer, Salvador J. Jaime, Arun Maharaj, Arturo Figueroa

International Journal of Exercise Science: Conference Proceedings

Sarcopenia, the age-related loss of skeletal muscle mass, has been associated with increased arterial stiffness (pulse wave velocity, PWV). Lower leg muscle mass has been associated with increased brachial-ankle PWV (baPWV), a measure of systemic arterial stiffness. Pulse pressure (PP) is lower in the aorta compared to the brachial artery (PP amplification, PPA), in healthy individuals. PPA decreases with aging due to increased aortic stiffening. Lower PPA is an independent predictor of cardiovascular death. It is unknown whether leg muscle mass is associated with lower PPA in postmenopausal women. Purpose: To examine relationships between leg lean mass (LegLM), PPA, and …

Low Intensity Exercise Has Greater Acute Vascular Benefits For Reducing Arterial Stiffness In Hot Compared To Neutral Conditions, Kyleigh N. Allie, Julianna Kilpatrick, Paolo Salvador, Eric Rivas

International Journal of Exercise Science: Conference Proceedings

Both exercise and passive heating cause acute reductions in blood pressure. It is unknown if exercise-heat stress causes likewise reductions or greater when combined. PURPOSE: This project tested the hypothesis that the resting and exercise-heat stress cause hypotension and improvements in arterial stiffness. METHODS: Seven healthy active (7 day activity: 9887±3564 steps/day; VO2max: 52±10 mL/kg/min ) subjects (5M/2F, 24±9y, 171±6cm, 68±7kg) completed a 30 min baseline rest followed by 60 min at an exercise intensity of their choice that represented their perceived exertion (RPE) of 12 (between light and somewhat hard) on a 20-point rating scale while being blinded to …

The Effects Of A Single Bout Of Endurance Exercise On Glucose Transporter-4 (Glut-4) Content, Manuel Gomez, Sudip Bajpeyi

International Journal of Exercise Science: Conference Proceedings

Glucose Transporter protein-4 (GLUT-4) is considered the predominant glucose transporter in skeletal muscle. Exercise has been shown to increase glucose uptake and GLUT-4 protein content in skeletal muscle following muscle contraction. PURPOSE: To determine the acute effects of a single bout of moderate intensity endurance exercise on skeletal muscle GLUT-4 content. METHODS: 10 healthy male volunteers (age: 24.4 ± 1.3 years; BMI 23.16 ± 0.60 kg/m²) participated in a single bout of endurance exercise on a cycle ergometer at 65% maximal aerobic capacity (VO_2max) for 1.5 – 2.0 hours (650kcal). Muscle biopsies were obtained from the vastus …

Intra-Day Variation In Lean Body Mass And Skeletal Muscle Mass Measures: A Pilot Study, Noe Deanda, Jordan B. Wainwright, Jeb F. Struder, Daniel Newmire

International Journal of Exercise Science: Conference Proceedings

Lean body mass (LBM) and its estimated measure of skeletal muscle mass (SKMM) is ~30 to ~40 % of total body weight. Measuring SKMM is an important assessment for both exercise and nutritional research. There is biological variation in dual X-ray absorptiometry (DXA) estimates related to subject presentation, changes in tissue hydration, as well as GI tract contents. PURPOSE: The purpose of this study is to examine how normal activities (e.g. eating, sleeping, exercise) influence LBM and SKMM measures using DXA in college students. METHODS: (Mean ± SEM; n = 42; Age: 26.9 ± 0.4 y; ht: 169.2 …

A Clinical Teaching Of Hamstring Strains, Josey Meyer, Chuck Ruot, Lindsay Edwards

International Journal of Exercise Science: Conference Proceedings

CLINICAL PRESENTATION & EXAM: A patient with a hamstring strain will have pain and tenderness on his or her posterior thigh. The patient may also complain of difficulty extending the knee and sitting comfortably. Depending on the severity of the injury, there could be bruising and swelling in the thigh area causing a loss of hamstring strength. If one of the hamstring muscles is completely torn; the patient would feel a “popping” sensation upon injury. Thus, the patient would be unable to use the injured leg. A hamstring strain typically comes from muscle overload during an eccentric contraction. A …

Exercise Leads To Increase In Smaller Lipid Droplet Morphology In Peripheral Region Of Muscle Fiber, Victoria Rosas

International Journal of Exercise Science: Conference Proceedings

In a previous study, we have shown that high fat overfeeding results in decreased smaller lipid droplet density in the peripheral region of skeletal muscle fiber. This decrease was associated with high fat overfeeding induced weight gain and insulin resistance. However, it is not clear whether an acute bout of exercise (elevated fat oxidation state) affects lipid droplet size. PURPOSE: To determine the effects of a single bout of endurance exercise on skeletal muscle lipid content and lipid droplet size. METHODS: Ten healthy male volunteers (Mean ± SEM; age: 23.11 ± 0.98; BMI: 23.27 ± 0.50 kg/m²) participated …

The Impact Of Kinetic Energy Factors On Pitching Performance Of Ncaa Baseball Players, Blake George, Andrew A. Wolfe, Joe W. Priest, Randy Martin, Matt Laurent, Kayla Peak

International Journal of Exercise Science: Conference Proceedings

Kinetic energy is established by a mathematical equation involving the mass of an object and the speed at which the object travels, and is a relevant measure in regards to athletic performance due to frequent transfer of energy during sport (i.e. athlete to athlete (tackling), athlete to object (throwing), object to object (tennis/baseball hitting)). Previous research has utilized the 60-yd run-shuttle to examine kinetic energy factors (k-factor) of difference sports, recognizing significant differences in energy capability between gender, sport teams, and individual sport positions. The utilization of k-factor, pertaining to baseball, has distinguished significant positional (i.e. infielder, outfielder, catcher, pitcher) …

Persistent Neurovascular Coupling Dysregulation During Subacute Recovery Phase Following Concussion, Sydney H. Lyng, Emma-Kate Brown, Tonia Sabo, Kathleen R. Bell, Sushmita Purkayastha

International Journal of Exercise Science: Conference Proceedings

Concussion diagnosis is characterized by a lack of objective markers, as there is a paucity of better understanding of the pathophysiology. Neurovascular coupling (NVC), an important factor in cerebral blood flow (CBF) regulation, is a tight temporal relationship between neuronal activity and CBF in order to meet cerebral metabolism. PURPOSE: To examine NVC on Day-3, Day-21, and Day-90 following a concussion in comparison to the non-injured healthy controls. METHODS: Twenty-nine male and female collegiate athletes (20±1years) sustaining a sports-related concussion were enrolled in a longitudinal study. For the concussed athletes, data were obtained on Day-3 (N=29), Day-21 (N=26), …

A Comparison Of High-Intensity Interval Exercise And Continuous Moderate-Intensity Exercise On Postprandial Metabolism: A Pilot Analysis., David J. Buckley, Broderick L. Dickerson, James R. Rowe Jr

International Journal of Exercise Science: Conference Proceedings

Both moderate-intensity continuous exercise (MICE) (performed for ≥ 1 hour) and high-intensity interval exercise (HIIE) (performed for ≤ 30 minutes) has been reported to reduce the magnitude of postprandial lipemia and glycemia. It is unclear if low-volume MICE and HIIE performed for a similar duration and expending similar amounts of energy would have a comparable or different effect on postprandial lipemia or glycemia. PURPOSE: Examine the effects of low-volume MICE and HIIE on postprandial glucose, insulin, and triglyceride (TG) concentration following a mixed meal (MM) ingested at 0.5 hours and 15.5 hours post-exercise. METHODS: Recreationally active men (n = …