Life Sciences Commons^™

Pre-Training Muscle Characteristics Of Subjects Who Are Obese Determine How Well Exercise Training Will Improve Their Insulin Responsiveness, Charles A. Stuart, Michelle L. Lee, Mark A. South, Mary E. A. Howell, Brian M. Cartwright, Michael W. Ramsey, Michael H. Stone

Mark A. South

Pre-training muscle characteristics of subjects who are obese determine how well exercise training will improve their insulin responsiveness. J Strength Cond Res 31(3): 798–808, 2017—Only half of prediabetic subjects who are obese who underwent exercise training without weight loss increased their insulin responsiveness. We hypothesized that those who improved their insulin responsiveness might have pretraining characteristics favoring a positive response to exercise training. Thirty nondiabetic subjects who were obese volunteered for 8 weeks of either strength training or endurance training. During training, subjects increased their caloric intake to prevent weight loss. Insulin responsiveness by euglycemic clamps and muscle fiber composition, …

Insulin Responsiveness In Metabolic Syndrome After Eight Weeks Of Cycle Training, Charles A. Stuart, Mark A. South, Michelle L. Lee, Melanie P. Mccurry, Mary E. A. Howell, Michael W. Ramsey, Michael H. Stone

Mark A. South

Introduction Insulin resistance in obesity is decreased after successful diet and exercise. Aerobic exercise training alone was evaluated as an intervention in subjects with the metabolic syndrome.

Methods Eighteen nondiabetic, sedentary subjects, 11 with the metabolic syndrome, participated in 8 wk of increasing intensity stationary cycle training.

Results Cycle training without weight loss did not change insulin resistance in metabolic syndrome subjects or sedentary control subjects. Maximal oxygen consumption (V˙O2max), activated muscle AMP-dependent kinase, and muscle mitochondrial marker ATP synthase all increased. Strength, lean body mass, and fat mass did not change. The activated mammalian target of rapamycin was not …

The Acute Effects Of Whole Body Vibration On Isometric Mid-Thigh Pull Performance, W. Guy Hornsby, Mark A. South, Ashley Kavanaugh, Andrew S. Layne, G. Gregory Haff, William A. Sands, Marco Cardinale, Michael W. Ramsey, Michael H. Stone

Mark A. South

Acute exposure to vibration has been suggested to produce transient increases in muscular strength (1,2,8), vertical jump displacement (4,8), and power output (2,6,7) recorded while performing various tasks. It has been hypothesized that the reported acute vibration induced increases in performance occur as a result of alterations in neuromuscular stimulation (1,3,4). Specifically, most studies have ascribed the observed improvements to the likeliness of Whole Body Vibration (WBV) in producing a “tonic vibration reflex” (TVR) in which the primary nerve endings of the Ia afferents of the muscle spindle are activated. This is thought to result in the excitation of the …

Pkd1 Inhibits Ampk2 Through Phosphorylation Of Serine 491 And Impairs Insulin Signaling In Skeletal Muscle Cells, Kimberly A. Coughlan, Rudy J. Valentine, Bella S. Sudit, Katherine Allen, Yossi Dagon, Barbara B. Kahn, Neil B. Ruderman, Asish K. Saha

Rudy Valentine

Background: Diminished activity of the enzyme AMP-activated protein kinase (AMPK) is associated with impaired insulin signaling.

Results: Protein Kinase (PK)C/D1 activation inhibits AMPK2 via Ser491 phosphorylation; PKD1 inhibition prevents this in skeletal muscle cells.

Conclusion: PKD1 is a novel upstream AMPK-kinase that phosphorylates AMPK on Ser491 and regulates insulin signaling.

Significance: PKD1 inhibition may be a novel strategy for improving insulin sensitivity.

Nutrient Excess And Ampk Downregulation In Incubated Skeletal Muscle And Muscle Of Glucose Infused Rats, Kimberly A. Coughlan, Thomas W. Balon, Rudy J. Valentine, Robert Petrocelli, Vera Schultz, Amana Brandon, Gregory J. Cooney, Edward W. Kraegen, Neil B. Ruderman, Asish K. Saha

Rudy Valentine

We have previously shown that incubation for 1h with excess glucose or leucine causes insulin resistance in rat extensor digitorum longus (EDL) muscle by inhibiting AMP-activated protein kinase (AMPK). To examine the events that precede and follow these changes, studies were performed in rat EDL incubated with elevated levels of glucose or leucine for 30min-2h. Incubation in high glucose (25mM) or leucine (100μM) significantly diminished AMPK activity by 50% within 30min, with further decreases occurring at 1 and 2h. The initial decrease in activity at 30min coincided with a significant increase in muscle glycogen. The subsequent decreases at 1h were …

Whole Egg Consumption Impairs Insulin Sensitivity In Rat Model Of Obesity And Type 2 Diabetes, Cassondra J. Saande, Megan A. Steffes, Joseph L. Webb, Rudy J. Valentine, Matthew J. Rowling, Kevin Schalinske

Rudy Valentine

Background: The literature regarding the relation between egg consumption and type 2 diabetes (T2D) is inconsistent and there is limited evidence pertaining to the impact of egg consumption on measures of insulin sensitivity. Objective: The objective of this study was to investigate the effect of dietary whole egg on metabolic biomarkers of insulin resistance in T2D rats. Downloaded from https://academic.oup.com/cdn/advance-article-abstract/doi/10.1093/cdn/nzz015/5374517 by Iowa State University user on 28 March 2019 Methods: Male Zucker diabetic fatty rats (n=12; 6 wk of age) and their lean controls (n=12; 6 wk of age) were randomly assigned to a casein- or whole egg-based diet. At …

Inhibition Of Triggering Receptor Expressed On Myeloid Cells 1 Ameliorates Inflammation And Macrophage And Neutrophil Activation In Alcoholic Liver Disease In Mice, David Tornai, Istvan Furi, Zu T. Shen, Alexander B. Sigalov, Sahin Coban, Gyongyi Szabo

Gyongyi Szabo

Alcoholic liver disease (ALD) is characterized by macrophage and neutrophil leukocyte recruitment and activation in the liver. Damage- and pathogen-associated molecular patterns contribute to a self-perpetuating proinflammatory state in ALD. Triggering receptor expressed on myeloid cells 1 (TREM-1) is a surface receptor that amplifies inflammation induced by toll-like receptors (TLRs) and is expressed on neutrophils and monocytes/macrophages. We hypothesized that TREM-1 signaling contributes to proinflammatory pathway activation in ALD. Using an in vivo ALD model in mice, we tested the effects of ligand-independent TREM-1 inhibitory peptides that were formulated into human high-density lipoprotein (HDL)-mimicking complexes GF9-HDL and GA/E31-HDL. As revealed …

Effect Of Exercise Position On Percent Changes In Serratus Anterior Muscle Thickness, Joseph M. Day

Joseph M. "Matt" Day

Objective: A reliable method for measuring SA thickness with ultrasound imaging has been reported, yet the ability to detect differences in levels of contractility has yet to be established. The purpose of this study was to determine if there are differences in the percent change in thickness of the SA during four different exercise positions performed by healthy individuals.

Design: Observational study

Setting: Laboratory

Participants: Twenty-eight healthy participants, mean age 26 (SD 4, 57% female, 100% right handed)

Methods: Volunteers were positioned in a standardized sitting posture and anatomical landmarks were marked for ultrasound probe positioning. Two resting and two …

Differences In Semg Between Normal Squats And Accentuated Eccentric Loaded Squats In Competitive Collegiate Weightlifters, Christopher Macdonalds, Kimitake Sato, Christian Carter, Hugh Lamont, William Sands, Michael H. Stone, Michael Israetel, Jeremy A. Gentles, Jason Cholewa, John Garner, Michael Ramsey, Guy Hornsby

Jeremy A. Gentles

The purpose of the present work was to compare the effect of accentuated eccentric loaded (AEL) squats to normally loaded (NOR) squats on surface measured muscle activation (sEMG) in competitive weightlifters. Eight experienced, competitive weightlifters (six males, two females) completed both an AEL and NOR squat session (seven days apart), comprised of nine sets of squats, and was identical to their normal scheduled training. sEMG data from the vastus medialis (VM), vastus lateralis (VL), and biceps femoris (BF) was collected (at 1000Hz) during the entirety of the concentric (CON) phases of the AEL and NOR sessions. RMANOVAs (set x session-type) …

Relationships Between Jump Characteristics Of Collegiate Female Athletes Competing In Different Disciplines, Christopher J. Macdonalds, Hugh S. Lamont, John C. Garner, Jeremy A. Gentles, Ashley A. Kavanaugh, Michael H. Stone

Jeremy A. Gentles

No abstract provided.

Cell Free Dna As A Marker Of Training Status In Weightlifters, Jeremy A. Gentles, William G. Hornsby, Christine L. Coniglio, Andy R. Dotterweich, Jon A. Miller, Charles A. Stuart, Michael H. Stone

Jeremy A. Gentles

The purpose of this investigation was to elucidate the changes in cf-DNA as it relates to fluctuations in resistance training workloads and intensities. The relationship between cell free DNA (cf-DNA), C-reactive protein (CRP), creatine kinase (CK), testosterone (T), cortisol (C), testosterone-cortisol ratio (T:C), body mass and body composition were also examined. Eight weightlifters (5 males and 3 females, age = 25 ± 3.5 yr, body mass = 88.3 ± 22.7 kg, height = 173.8 ±8.4 cm) volunteered to participate in this study. Venous blood samples, body mass and body composition were taken six times, each corresponding to the end of …

The Effects Of Strength Training On Isometric Force Production Symmetry In Recreationally Trained Males, Caleb D. Bazyler, Christopher A. Bailey, Chieh-Ying Chiang, Kimitake Sato, Michael H. Stone

Michael H. Stone

Objectives: The purpose of this investigation was to determine what effect a bilateral strength training regimen has on isometric force production symmetry and if changes in force production symmetry can be accounted for by differences in pre-intervention strength levels. Design: Sixteen recreationally trained males (1-RM squat: 146.8 ± 23.0 kg.) were assigned to two groups for the 7-week training intervention: strong (S) and weak (W) based on pre-training squat isometric peak force allometrically scaled (IPFa) at 120° knee angle. Methods: Subjects completed a 7-week training intervention following a block-periodized model and were tested on measures of dynamic (1RM squat) and …

Maximum Strength, Rate Of Force Development, Jump Height, And Peak Power Alterations In Weightlifters Across Five Months Of Training, W. Guy Hornsby, Jeremy A. Gentles, Christopher J. Macdonald, Satoshi Mizuguchi, Michael W. Ramsey, Michael H. Stone

Michael H. Stone

The purpose of this monitoring study was to investigate how alterations in training affect changes in force-related characteristics and weightlifting performance. Subjects: Seven competitive weightlifters participated in the study. Methods: The weightlifters performed a block style periodized plan across 20 weeks. Force plate data from the isometric mid-thigh pull and static jumps with 0 kg, 11 kg, and 20 kg were collected near the end of each training block (weeks 1, 6, 10, 13, 17, and 20). Weightlifting performance was measured at weeks 0, 7, 11, and 20. Results: Very strong correlations were noted between weightlifting performances and isometric rate …

The Acute Effects Of Whole Body Vibration On Isometric Mid-Thigh Pull Performance, W. Guy Hornsby, Mark A. South, Ashley Kavanaugh, Andrew S. Layne, G. Gregory Haff, William A. Sands, Marco Cardinale, Michael W. Ramsey, Michael H. Stone

Michael W. Ramsey

Acute exposure to vibration has been suggested to produce transient increases in muscular strength (1,2,8), vertical jump displacement (4,8), and power output (2,6,7) recorded while performing various tasks. It has been hypothesized that the reported acute vibration induced increases in performance occur as a result of alterations in neuromuscular stimulation (1,3,4). Specifically, most studies have ascribed the observed improvements to the likeliness of Whole Body Vibration (WBV) in producing a “tonic vibration reflex” (TVR) in which the primary nerve endings of the Ia afferents of the muscle spindle are activated. This is thought to result in the excitation of the …

Pre-Training Muscle Characteristics Of Subjects Who Are Obese Determine How Well Exercise Training Will Improve Their Insulin Responsiveness, Charles A. Stuart, Michelle L. Lee, Mark A. South, Mary E. A. Howell, Brian M. Cartwright, Michael W. Ramsey, Michael H. Stone

Michael W. Ramsey

Pre-training muscle characteristics of subjects who are obese determine how well exercise training will improve their insulin responsiveness. J Strength Cond Res 31(3): 798–808, 2017—Only half of prediabetic subjects who are obese who underwent exercise training without weight loss increased their insulin responsiveness. We hypothesized that those who improved their insulin responsiveness might have pretraining characteristics favoring a positive response to exercise training. Thirty nondiabetic subjects who were obese volunteered for 8 weeks of either strength training or endurance training. During training, subjects increased their caloric intake to prevent weight loss. Insulin responsiveness by euglycemic clamps and muscle fiber composition, …

Resting Hormone Alterations And Injuries: Block Vs. Dup Weight-Training Among D-1 Track And Field Athletes, Keith B. Painter, G. Gregory Haff, N. Travis Triplett, Charles Stuart, Guy Hornsby, Mike W. Ramsey, Caleb D. Bazyler, Michael H. Stone

Michael W. Ramsey

Daily undulating periodization (DUP), using daily alterations in repetitions, has been advocated as a superior method of resistance training, while traditional forms of programming for periodization (Block) have been questioned. Nineteen Division I track and field athletes were assigned to either a 10-week Block or DUP training group. Year and event were controlled. Over the course of the study, there were four testing sessions, which were used to evaluate a variety of strength characteristics, including maximum isometric strength, rate of force development, and one repetition maximum (1RM). Although, performance trends favored the Block group for strength and rate of force …

Insulin Responsiveness In Metabolic Syndrome After Eight Weeks Of Cycle Training, Charles A. Stuart, Mark A. South, Michelle L. Lee, Melanie P. Mccurry, Mary E. A. Howell, Michael W. Ramsey, Michael H. Stone

Michael W. Ramsey

Introduction Insulin resistance in obesity is decreased after successful diet and exercise. Aerobic exercise training alone was evaluated as an intervention in subjects with the metabolic syndrome.

Methods Eighteen nondiabetic, sedentary subjects, 11 with the metabolic syndrome, participated in 8 wk of increasing intensity stationary cycle training.

Results Cycle training without weight loss did not change insulin resistance in metabolic syndrome subjects or sedentary control subjects. Maximal oxygen consumption (V˙O2max), activated muscle AMP-dependent kinase, and muscle mitochondrial marker ATP synthase all increased. Strength, lean body mass, and fat mass did not change. The activated mammalian target of rapamycin was not …

The Demands Of A Women's College Soccer Season, Jeremy A. Gentles, Christine L. Coniglio, Matthew M. Besemer, Joshua M. Morgan, Michael T. Mahnken

Jeremy A. Gentles

No abstract provided.

Utilizing Weightlifting For Cycling Performance, Nicholas J. Fiolo, Christopher B. Taber, Caleb D. Bazyler, Cody T. Haun, Robert Duncan, Aaron M. Thomas, Michael W. Ramsey, Michael H. Stone

Caleb D. Bazyler

Abstract available in the 9th Annual Coaches and Sport Science College.

The Efficacy Of Partial Squats On Measures Of Strength And Explosiveness: An Exploratory Study, Caleb D. Bazyler, Kimitake Sato, Craig A. Wassinger, Hugh S. Lamont, Michael H. Stone

Caleb D. Bazyler

Abstract available in the 8th Annual Coaches and Sport Science College.

The Relationship Of Force Production Asymmetry And Performance In Athletes Of Different Strength Levels, Christopher A. Bailey, Caleb D. Bazyler, Chieh-Ying Chiang, Kimitake Sato, Michael H. Stone

Caleb D. Bazyler

The purpose of this study was to evaluate the relationship between force production asymmetry and performance of athletes with differing strength levels in males and females. Collegiate athletes (n=129) from various sports were ranked according to isometric mid-thigh pull peak force and the top (‘strong’) and bottom (‘weak’) 25% were used for analysis. Symmetry index (SI) scores were calculated and correlated with their respective force-time characteristics using bivariate correlations. For the weaker males, several negative moderate correlations were observed; however, no statistically significant correlations were observed for the females in either group. These findings indicate that force production asymmetry is …

Force Output Comparison Between Six U.S. Collegiate Athletic Teams., Caleb D. Bazyler, George Beckham, Howard Gray, Guy Hornsby, Ashley A. Kavanaugh, Christopher Macdonald, Satoshi Mizuguchi, Michael H. Stone, Michael H. Stone

Caleb D. Bazyler

The aim of the study was to compare allometrically scaled peak force and the force at 250 ms between six U.S. collegiate sport teams using isometric mid-thigh pull. Ninety subjects performed maximum effort of isometric mid-thigh pull to measure force output. The data were averaged within the teams, and statistically compared between teams using one-way ANOVA (p=.01). Significant difference was found that men’s soccer and baseball produced higher allometrically scaled peak force, and men’s soccer, tennis, and baseball produced higher allometrically scaled force at 250 ms. The data indicates that not all sports possess similar strength characteristics because of the …

Analysis Of Changes In Muscle Architecture And Explosive Ability In Ncaa Division I Volleyball Players, Caleb D. Bazyler, Jacob R. Goodin, Conrad Rapp, Mark Disanto, Frank Smith, Michael H. Stone

Caleb D. Bazyler

Abstract available in the 10th Annual Coaches and Sport Science College .

Resting Hormone Alterations And Injuries: Block Vs. Dup Weight-Training Among D-1 Track And Field Athletes, Keith B. Painter, G. Gregory Haff, N. Travis Triplett, Charles Stuart, Guy Hornsby, Mike W. Ramsey, Caleb D. Bazyler, Michael H. Stone

Caleb D. Bazyler

Daily undulating periodization (DUP), using daily alterations in repetitions, has been advocated as a superior method of resistance training, while traditional forms of programming for periodization (Block) have been questioned. Nineteen Division I track and field athletes were assigned to either a 10-week Block or DUP training group. Year and event were controlled. Over the course of the study, there were four testing sessions, which were used to evaluate a variety of strength characteristics, including maximum isometric strength, rate of force development, and one repetition maximum (1RM). Although, performance trends favored the Block group for strength and rate of force …

The Effects Of Strength Training On Isometric Force Production Symmetry In Recreationally Trained Males, Caleb D. Bazyler, Christopher A. Bailey, Chieh-Ying Chiang, Kimitake Sato, Michael H. Stone

Caleb D. Bazyler

Objectives: The purpose of this investigation was to determine what effect a bilateral strength training regimen has on isometric force production symmetry and if changes in force production symmetry can be accounted for by differences in pre-intervention strength levels. Design: Sixteen recreationally trained males (1-RM squat: 146.8 ± 23.0 kg.) were assigned to two groups for the 7-week training intervention: strong (S) and weak (W) based on pre-training squat isometric peak force allometrically scaled (IPFa) at 120° knee angle. Methods: Subjects completed a 7-week training intervention following a block-periodized model and were tested on measures of dynamic (1RM squat) and …

Returners Exhibit Greater Jumping Performance Improvements During A Peaking Phase Compared With New Players On A Volleyball Team, Caleb D. Bazyler, Satoshi Mizuguchi, Ashley A. Kavanaugh, John J. Mcmahon, Paul Comfort, Michael H. Stone

Caleb D. Bazyler

Purpose: To determine if jumping-performance changes during a peaking phase differed among returners and new players on a female collegiate volleyball team and to determine which variables best explained the variation in performance changes.

Methods: Fourteen volleyball players were divided into 2 groups—returners (n = 7) and new players (n = 7)—who completed a 5-wk peaking phase prior to conference championships. Players were tested at baseline before the preseason on measures of the vastus lateralis cross-sectional area using ultrasonography, estimated back-squat 1-repetition maximum, countermovement jump height (JH), and relative peak power on a force platform. Jumping performance, rating of perceived …

Increases In Variation Of Barbell Kinematics Are Observed With Increasing Intensity In A Graded Back Squat Test, Kevin M. Carroll, Kimitake Sato, Caleb D. Bazyler, N. Travis Triplett, Michael H. Stone

Caleb D. Bazyler

The purpose of the current study was two-fold: (1) To examine the variation in velocity and power with increasing intensity in the back squat among subjects; and (2) To explore individual subject characteristics as possible explanations for variations of velocity in the back squat. Fourteen recreationally trained male subjects with experience in the back squat agreed to participate in the study (age = 25.0 ± 2.6 years, height = 178.9 ± 8.1 cm, body mass = 88.2 ± 15.8 kg). One-repetition maximums (1RM) were performed for each subject on force platforms with four linear position transducers attached to the barbell. …

Current Research And Statistical Practices In Sport Science And A Need For Change, Jake R. Bernards, Kimitake Sato, G. Gregory Haff, Caleb D. Bazyler

Caleb D. Bazyler

Current research ideologies in sport science allow for the possibility of investigators producing statistically significant results to help fit the outcome into a predetermined theory. Additionally, under the current Neyman-Pearson statistical structure, some argue that null hypothesis significant testing (NHST) under the frequentist approach is flawed, regardless. For example, a p-value is unable to measure the probability that the studied hypothesis is true, unable to measure the size of an effect or the importance of a result, and unable to provide a good measure of evidence regarding a model or hypothesis. Many of these downfalls are key questions researchers strive …

Cell Free Dna As A Marker Of Training Status In Weightlifters, Jeremy A. Gentles, William G. Hornsby, Christine L. Coniglio, Andy R. Dotterweich, Jon A. Miller, Charles A. Stuart, Michael H. Stone

Andy R. Dotterweich

The purpose of this investigation was to elucidate the changes in cf-DNA as it relates to fluctuations in resistance training workloads and intensities. The relationship between cell free DNA (cf-DNA), C-reactive protein (CRP), creatine kinase (CK), testosterone (T), cortisol (C), testosterone-cortisol ratio (T:C), body mass and body composition were also examined. Eight weightlifters (5 males and 3 females, age = 25 ± 3.5 yr, body mass = 88.3 ± 22.7 kg, height = 173.8 ±8.4 cm) volunteered to participate in this study. Venous blood samples, body mass and body composition were taken six times, each corresponding to the end of …

Proteomic Profiling Of Serum Derived Exosomes From Prostate Cancer Patients, David Turay

David Turay, MD

Touted among the major achievements in the diagnosis and management of Prostate cancer (PCa) in the past few decades has been, the dramatic decline of men with advanced/metastatic PCa at diagnosis coupled with a significant improvement ( >90%) in the five and ten year survival rates of the disease. Non-palpable PCa (potentially clinically treatable disease) now accounts for 70-80% of all newly diagnosed cases of PCa. Preceding these changes by about a decade was the introduction of Prostatic Specific Antigen (PSA) into clinical practice; first as biomarker for monitoring response to therapy and subsequently as a complementary screening tool. It …