Exercise Science Commons^™

Evidence For The Use Of Dynamic Maximum Normalization Method Of Muscle Activation During Weight Back Squats, Eva Maddox, Hunter J. Bennett

College of Education & Professional Studies (Darden) Posters

The purpose of this study was to evaluate intra and inter-participant variability and reliability of muscle activations when analyzed using maximum voluntary isometric contractions (MVIC) and dynamic maximum (DMVC) normalization methods. Muscle activations were collected on twenty-seven participants (13 females, 14 males) performing one-repetition maximum (1RM) and submaximum (80%) back squats. Data from submaximum squats were normalized to MVICs and DMVCs. Data were compared using intra-class correlations over two testing days, variance ratio, and coefficients of variation. Mixed-model ANOVAs were used to elucidate the influence on intra- (method) and inter- (sex) subject variability. Reliability levels were good for rectus femoris …

Sexual Dimorphism In Response To Repetitive Bouts Of Acute Exercise In Rodents With Type 1 Diabetes Mellitus, Jordan C. Larocque

Electronic Thesis and Dissertation Repository

The purpose of this study was to examine sex-specific differences in the blood glucose (BG) response to recurrent aerobic exercise in type 1 diabetes. Specifically, we examined the role of peak estrogen (E2) concentrations during proestrus on BG response to prolonged aerobic exercise. To do so, nineteen Sprague-Dawley rats were assigned to four exercised groups: control female (CXF; n = 5), control male (CXM; n = 5), diabetic female (DXF, n = 5) and diabetic male (DXM, n = 4). Diabetes was induced in DX groups via subcutaneous injection of low dose streptozotocin. After four days of exercise, liver glycogen …

Effect Of Strength On Velocity And Power During Back Squat Exercise In Resistance-Trained Men And Women, Andrew T. Askow, Justin J. Merrigan, Jonathan M. Neddo, Jonathan M. Oliver, Jason D. Stone, Andrew R. Jagim, Margaret T. Jones

Faculty Scholarship

The purpose was to examine load-velocity and load-power relationships of back squat in resistance-trained men (n = 20, 21.3 ± 1.4 years, 183.0 ± 8.0 cm, 82.6 ± 8.0 kg, 11.5 ± 5.0% total body fat) and women (n = 18; 20.0 ± 1.0 years; 166.5 ± 6.9 cm; 63.9 ± 7.9 kg, 20.3 ± 5.0% body fat). Body composition testing was performed followed by determination of back squat 1 repetition maximum (1RM). After at least 72 hours of recovery, subjects returned to the laboratory and completed 2 repetitions at each of 7 separate loads (30, 40, 50, …

Fascicle Arrangement In College-Aged Athletes, Jacob Goodin

Electronic Theses and Dissertations

Purpose: To compare muscle architecture variables between sport and sex in competitive athletes, and to compare muscle architecture with performance variables in strong versus weak athletes, and good versus poor jumpers. Methods: The vastus lateralis (VL) and lateral gastrocnemius (LG) muscles of 139 collegiate athletes were collected using ultrasonography to determine muscle thickness (MT), pennation angle (PA), fascicle length (FL), and relative fascicle length (FL_rel). Absolute and relative peak power, absolute and relative isometric peak force, and jump height were measured in a subset of baseball and soccer athletes. A 5x2 factorial analysis of variance (ANOVA) was used …

Role Of Skeletal Muscle Mass In Sex-Dependent Power Output During Flywheel Resistance Training, Paul A. Baker

Theses and Dissertations--Kinesiology and Health Promotion

Background: To determine the role of muscle mass in sex-dependent differences in power output during flywheel resistance training (FRT).

Methods: Twenty recreationally active (≥ 2 resistance exercise bouts per week), subjects (10 M, 10 F) completed 2 bouts of resistance exercise using a flywheel resistance training (FRT) device (Exxentric kbox 4 Pro) separated by at least one week. Each session consisted of 3 sets of 4 exercises (squat, bent-over row, Romanian deadlift, and biceps curl) with varying moments of inertia (0.050, 0.075, and 0.100 kg/m², respectively) in random order. Each set consisted of 5 maximal effort repetitions with …

Sex Differences In Neuromuscular Fatigability Of The Knee Extensors Post-Stroke, Meghan Kirking, Reivian B. Barillas, Philip A. Nelson, Sandra K. Hunter, Allison Hyngstrom

Exercise Science Faculty Research and Publications

Background and Purpose: Despite the implications of optimizing strength training post-stroke, little is known about the differences in fatigability between men and women with chronic stroke. The purpose of this study was to determine the sex differences in knee extensor muscle fatigability and potential mechanisms in individuals with stroke. Methods: Eighteen participants (10 men, eight women) with chronic stroke (≥6 months) and 23 (12 men, 11 women) nonstroke controls participated in the study. Participants performed an intermittent isometric contraction task (6 s contraction, 3 s rest) at 30% of maximal voluntary contraction (MVC) torque until failure to maintain the target …

Rates Of Performance Loss And Neuromuscular Activity In Men And Women During Cycling: Evidence For A Common Metabolic Basis Of Muscle Fatigue, Christopher W. Sundberg, Sandra K. Hunter, Matthew W. Bundle

Exercise Science Faculty Research and Publications

The durations that muscular force and power outputs can be sustained until failure fall predictably on an exponential decline between an individual’s 3-s burst maximum to the maximum performance they can sustain aerobically. The exponential time constants describing these rates of performance loss are similar across individuals, suggesting that a common metabolically based mechanism governs muscle fatigue; however, these conclusions come from studies mainly on men. To test whether the same physiological understanding can be applied to women, we compared the performance-duration relationships and neuromuscular activity between seven men [23.3 ± 1.9 (SD) yr] and seven women (21.7 ± 1.8 …

Fast Men Slow More Than Fast Women In A 10 Kilometer Road Race, Robert O. Deaner, Vittorio Addana, Rickey E. Carter, Michael J. Joyner, Sandra K. Hunter

Exercise Science Faculty Research and Publications

Background. Previous studies have demonstrated that men are more likely than women to slow in the marathon (footrace). This study investigated whether the sex difference in pacing occurs for a shorter race distance.

Materials & Methods.Data were acquired from the Bolder Boulder 10 km road race for the years 2008–2013, which encompassed 191,693 performances. There were two pacing measures, percentage change in pace of the first 3 miles relative to the final 3.2 miles and percentage change in pace of the first mile relative to the final 5.2 miles. Pacing was analyzed as a continuous variable and as two …

Invited Review: Heat Shock Proteins And Exercise: A Primer, Earl Noble, Kevin Milne, C.W. Melling

Jamie Melling

Heat shock proteins (HSPs) are, in general, prosurvival molecules within the cellular environment, and the overexpression of even just 1 family of HSPs can lead to protection against and improvements after a variety of stressors. Not surprisingly, a fertile area of study has grown out of effors to exploit the innate biologic behaviour of HSPs. Exercise, because of the inherent physiologic stresses associated with it, is but 1 stimulus that can result in a robust increase in various HSPs in several tissues, not the least of which happen to be the heart and skeletal muscle. The purpose of this review …

Technique And Performance Level Comparisons Of Male And Female Hammer Throwers, Suzanne M. Konz

Theses and Dissertations

The aim of this study was two-fold: 1) what the hammer throwing technique differences between sexes are and 2) what technique parameters help determine throw distance. The performances of the top 16 male and female throwers at the 2003 World Athletic Final and the top 13 male and female throwers from the 2003 USA Track and Field Nationals were examined. Video was captured using three Canon 60 Hz cameras. The best throws of each athlete were digitized and analyzed using the Peak Motus 8.2 motion analysis system. T-tests revealed that athlete mass, athlete height, velocity at release, timing components, and …