Physiology Commons^™

Role Of Hepatic Cholesterol Ester Hydrolase (Ceh) In Hydrolyzing Cholesterol Esters (Ce) Delivered Via Sr-Bi (Scavenger Receptor Class B Type I) And Sr-Bii, Saurabh Bajpai

Theses and Dissertations

Reduction of cholesterol ester (CE) from lipid burden lesion-associated macrophage foam cells has been shown to reduce plaque volumes. Hydrolysis of CE to free cholesterol (FC) in macrophages is an essential step for removal of CE from the macrophage and its transport to the liver by high density lipoprotein (HDL) for further metabolism. Since CE must again be hydrolyzed into FC in the liver catalyzing this hydrolysis, it becomes imperative to find the identity of these enzymes. In this study the role of key enzyme in catalyzing the hydrolysis of CE to FC, neutral cholesterol ester hydrolase (CEH) was evaluated. …

Matrix Metalloproteinase Expression In Models Of Parkinson's Disease, Justin Mcclain

Theses and Dissertations

Parkinson’s disease (PD) is a devastating neurodegenerative disorder characterized by progressive loss of dopaminergic neurons located in the substantia nigra. Accumulating evidence indicates that microglia-driven neuroinflammation contributes significantly to chronic neurodegeneration in PD. The matrix metalloproteinases (MMPs) play an important role in several neuroinflammatory paradigms; however, their relationship to dopaminergic neurodegeneration in PD remains relatively unexplored. To address this, the temporal relationship between MMP-2, MMP-3, MMP-9, and MMP-13 expression and dopaminergic neurodegeneration was compared in the 6-hydroxydopamine (6-OHDA) and lipopolysaccharide (LPS) models of PD. In dopaminergic SH-SY5Y cells, 6-OHDA treatment significantly increased MMP-13 mRNA expression; however, examination of 6-OHDA-lesioned rats …

Lrp1 Shedding In Human Brain: Roles Of Adam10 And Adam17, Qiang Liu, Juan Zhang, Hien Tran, Marcel M. Verbeek, Karina Reiss, Steven Estus, Guojun Bu

Physiology Faculty Publications

BACKGROUND: The low-density lipoprotein receptor-related protein 1 (LRP1) plays critical roles in lipid metabolism, cell survival, and the clearance of amyloid-beta (Abeta) peptide. Functional soluble LRP1 (sLRP1) has been detected in circulating human placenta; however, whether sLRP1 is also present in the central nervous system is unclear.

RESULTS: Here we show that abundant sLRP1 capable of binding its ligands is present in human brain tissue and cerebral spinal fluid (CSF). Interestingly, the levels of sLRP1 in CSF are significantly increased in older individuals, suggesting that either LRP1 shedding is increased or sLRP1 clearance is decreased during aging. To examine potential …

Power Training: Can It Improve Functional Performance In Older Adults? A Systematic Review, John Rice†, Justin Keogh‡

International Journal of Exercise Science

Older adults’ reduced performance in functional activities of daily living (ADL) such as gait, sit to stand or stair climbing may reflect age-related declines in muscular power more so than strength. Therefore, this review was conducted to determine if power training is effective in improving the functional ability of older adults, and if so, if it was more effective than strength training. The review was performed using Medline (PubMed), CINAHL, Sports Discus, ProQuest 5000 International and Google Scholar with the keywords “power training”, “older adult” and “elder” and all derivatives. Of the 12 eligible studies identified, nine also included a …

Determination Of Systolic Blood Pressure Recovery Time After Exercise In Apparently Healthy, Normotensive, Non-Athletic Adults And The Effects Of Age, Gender, And Exercise Intensity, Uchechukwu Dimkpa†, Andrew C. Ugwu‡

International Journal of Exercise Science

The aim of this study was to determine in statistical terms, the systolic blood pressure recovery time (SBPRT) and the effects of age, gender and exercise intensity in a large sample of apparently healthy non-athletic adults (n=597, aged 18-68). Subjects performed mild, moderate, and severe ergometer exercise tests. Blood pressure was measured before exercise (after 10 and 15 minutes of rest), during exercise (at 2-minute intervals) and at every minute of post-exercise recovery until systolic blood pressure (SBP) returned to baseline. The present findings indicate that the average values of SBPRT were between 5 and 7 minutes regardless of age, …

Anthropometric And Physiological Predictors Of Flat-Water 1000 M Kayak Performance In Young Adolescents And The Effectiveness Of A High Volume Training Camp., Scott C. Forbes†, Daniel L. Fuller†, Joel R. Krentz†, Jonathon P. Little†, Phillip D. Chilibeck‡

International Journal of Exercise Science

Our purpose was to determine the relationship of anthropometric and physiological variables with 1000m flat-water kayak (K1000) performance. A secondary purpose was to determine the effectiveness of a high volume training camp. High performance young adolescent kayakers (n=13, 8 males, 5 females, 15±1 yrs) participated in this study. Testing before and after the 3-4 week training camp included anthropometric measurements (height, sitting height, arm span, and body mass), strength (1-RM: bench press and bench pull), flexibility (sit and reach), and an incremental kayak ergometer test to determine peak oxygen uptake (VO2peak) and anaerobic threshold, and an open water K1000 time …

The Influence Of An Environmental Cue And Exercise On Food Consumption In College Students, Samantha J. Hackbart †, James D. Lecheminant‡, John D. Smith‡, Curt L. Lox‡

International Journal of Exercise Science

The purpose of this study was to determine the effect of an environmental cue (bowl size) on food consumption and to examine the influence of exercise on that relationship. This cross-sectional study included 286 college students attending a large Midwestern University. Upon arrival at an ice cream social for university students, participants were randomly given a small (8 oz) or large (12 oz) bowl and a 4-page survey addressing exercise and eating habits. At the social, participants were invited to dish themselves as much ice cream as they wanted and the amount consumed was determined by weighing the bowl with …

Determination Of Blood Lactate Concentration: Reliability And Validity Of A Lactate Oxidase-Based Method, Rachel White*, Daniel Yaeger*, Stasinos Stavrianeas‡

International Journal of Exercise Science

The measurement of blood lactate has long been used as marker of exercise intensity and training status. We compared a commercially available lactate oxidase spectrophotometric method (LO) to determine blood lactate levels to two previously validated methods, the lactate dehydrogenase spectrophotometric method (LDH), and the YSI 1500L Sport lactate analyzer (YSI). First we established a series of calibration curves over physiological range of lactate values (1-15 mM∙l-1 for the spectrophotometric assays and 1-30 mM∙l-1 for the YSI) with high correlations (0.986 < r < 0.999). Aerobically trained participants (n = 11) performed repeated exercise bouts of varying intensities on a cycle ergometer. Capillary blood samples (n = 189) were collected from the earlobe and the blood lactate concentration was determined using each of the three methods. An ANOVA (alpha=0.05) revealed no differences in blood lactate concentrations between the three methods. The three experimental protocols yielded similarly-shaped lactate curves, although the actual values for the LDH method was somewhat lower than the LO and the YSI at every intensity level. Bland-Altman plots revealed a slight bias towards lower lactate values with the LDH method, perhaps indicative of a more conservative measure of blood lactate. We conclude that the LO method is a reliable and valid method to determine blood lactate concentrations spectrophotometrically. All three methods can provide useful within-subject lactate curves, although we caution against interchangeable use of the three methods.

Spatting Restricts Ankle Motion More Effectively Than Taping During Exercise, Brian E. Udermann†, Kevin C. Miller†, Scott T. Doberstein‡, David M. Reineke‡, Steven R. Murray‡, Robert W. Pettitt‡

International Journal of Exercise Science

Ankle injuries, via plantarflexion (PF) and inversion, are commonplace today. To reduce ankle injuries, restrictive appliances such as taping and bracing have been employed. These appliances, however, have the disadvantage of potentially loosening considerably with mild activity. Spatting—applying tape over the shoe and sock—has been suggested as a viable alternative, yet its efficacy has not been researched widely. We examined the effects of taping or spatting the ankles on 17 men (age = 20.7 ± 2.1 years; height = 185.7 ± 5.7 cm; mass = 93.6 ± 16.2 kg) before, during, and after 60 minutes of exercise involving multi-directional activity. …

Mechanisms Of Regulation Of Proximal Tubule Sodium Transporters In Obesity-Induced Hypertension, Marta A. Ambrozewicz

Theses and Dissertations in Biomedical Sciences

Hypertension is one of the common complications of obesity. Using a rat model of diet induced obesity and hypertension we investigated some of the mechanisms that are involved in regulation of blood pressure in obesity. The first aim of this study was to determine the role of proximal tubule transporters on the renal sodium handling in obese hypertensive (OP) and lean normotensive (OR) rats. An acute increase in renal perfusion pressure resulted in a blunted natriuretic response in OP vs. OR rats and indicated that increased sodium reabsorption in the proximal tubule is casual, at least in part, for hypertension …

Resampling And Editing Of Mischarged Trna Prior To Translation Elongation, Jiqiang Ling, Byung Ran So, Srujana S. Yadavalli, Hervé Roy, Shinichiro Shoji, Kurt Fredrick, Karin Musier-Forsyth, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Faithful translation of the genetic code depends on the GTPase EF-Tu delivering correctly charged aminoacyl-tRNAs to the ribosome for pairing with cognate codons. The accurate coupling of cognate amino acids and tRNAs by the aminoacyl-tRNA synthetases is achieved through a combination of substrate specificity and product editing. Once released by aminoacyl-tRNA synthetases, both cognate and near-cognate aminoacyl-tRNAs were considered to be committed to ribosomal protein synthesis through their association with EF-Tu. Here we show instead that aminoacyl-tRNAs in ternary complex with EF-Tu•GTP can readily dissociate and rebind to aminoacyl-tRNA synthetases. For mischarged species, this allows resampling by the product editing …

Y27632, A Rho-Activated Kinase Inhibitor, Normalizes Dysregulation In Alpha1-Adrenergic Receptor-Induced Contraction Of Lyon Hypertensive Rat Artery Smooth Muscle., Maria Regina Freitas, Masumi Eto, Jason A Kirkbride, Christa Schott, Jean Sassard, Jean-Claude Stoclet

Department of Molecular Physiology and Biophysics Faculty Papers

RhoA-activated kinase (ROK) is involved in the disorders of smooth muscle contraction found in hypertension model animals and patients. We examined whether the alpha1-adrenergic receptor agonist-induced ROK signal is perturbed in resistance small mesentery artery (SMA) of Lyon genetically hypertensive (LH) rats, using a ROK antagonist, Y27632. Smooth muscle strips of SMA and aorta were isolated from LH and Lyon normotensive (LN) rats. After Ca(2+)-depletion and pre-treatment with phenylephrine (PE), smooth muscle contraction was induced by serial additions of CaCl(2). In LH SMA Ca(2+) permeated cells to a lesser extent as compared with LN SMA, while CaCl(2)-induced contraction of LH …

Role Of No In The Regulation Of Cortisol Synthesis In Long-Term Hypoxic Sheep Fetal Adrenal, Tshepo Rothi Monau

Loma Linda University Electronic Theses, Dissertations & Projects

Our laboratory has demonstrated that sheep fetuses adapt to long-term hypoxia (LTH) by maintaining normal level of basal plasma cortisol despite increased adrenocorticotropic hormone (ACTH). But the mechanisms involved are not fully understood. Studies have shown that nitric oxide (NO) inhibits synthesis of steroid hormones in a variety of tissues, and in different animal species. Studies also showed that hypoxia increases both expression and activity levels of the nitric oxide (NO) generating enzyme, nitric oxide synthase (NOS), in certain tissues. We have here investigated the expression level and localization of NOS isoforms in sheep fetal adrenals. We also investigated the …

Use Of The Timed Walk Test, Physiological Cost Index And Prosthesis Evaluation Questionnaire As Outcomes Measurements For The Validation Of The Legs M1 Knee, Katie Leatherwood, Wayne Jacobs, Karen Rispin

International Journal of Exercise Science: Conference Proceedings

LeTourneau Empowering Global Solutions (LEGS) administered a preliminary study comparing energy cost and patient satisfaction of three different prosthetic knee configurations. The LEGS M1 knee was compared with both a locked LEGS M1 knee and the OrthoEurope 4-bar (OE4bar) knee. Energy cost was measured using the Physiological Cost Index (PCI) and Timed Walk Test (TWT). Patient satisfaction was measured using the Prosthesis Evaluation Questionnaire (PEQ). The TWT and PCI indicated that the LEGS M1 knee was more costly to walk with than the OE4Bar conformation. In the comparison between the LEGS MI knee and the locked configuration, TWT and PCI …

Integral Effects Of Systemic Nitric Oxide Synthase Inhibition On Carotid Arterial Compliance, Jun Sugawara, Hidehiko Komine, Mutsuko Yoshizawa, Yoko Saito, Mariko Nakamura, Ryuichi Ajisaka, Seiji Maeda, Hirofumi Tanaka

International Journal of Exercise Science: Conference Proceedings

Decreased arterial compliance (increased arterial stiffness) is associated with cardiovascular events. Nitric oxide regulates vascular tone, which can influence arterial compliance. We previously investigated the effects of systemic nitric oxide synthase (NOS) inhibition on arterial compliance under the systemic α-adrenergic receptor blocking. In the present study, we investigated the effect of systemic NOS inhibition alone on central arterial compliance (via carotid arterial ultrasound imaging and applanation tonometry). Eighteen apparently healthy young adults (26±1 years) underwent intravenous infusions of NG-monomethyl-L-arginine (L-NMMA) or placebo (saline) on separate days. In the placebo control condition, no significant changes were observed in mean arterial pressure, …

Association Of Aerobic Fitness And Metabolic Syndrome In Male Firefighters, Christina Durcan, Jennifer M. Markos

International Journal of Exercise Science: Conference Proceedings

Association of Aerobic Fitness and Metabolic Syndrome in Male Firefighters. Durcan, C.M.*, S.E. Martin‡, B.S. Lambert†, N.P. Greene†, J.M. Markos†, A.F. Carbuhn†, J.S. Green‡, FACSM and S.F. Crouse‡, FACSM. Department of Health and Kinesiology, Texas A&M University, College Station, TX. Metabolic syndrome has been shown in numerous studies to be related to a higher incidence of coronary artery disease. A study by R. Jurca et.al., in Med. Sci. Sports Exerc 36(38), found a relationship between aerobic fitness and the prevalence of metabolic syndrome in a group of men enrolled in the Aerobics Center Longitudinal Study. Information on this relationship in …

Prediction Of The Total Energy Cost Of An Acute Bout Of Resistance Exercise In Young Men And Women, Brad S. Lambert, Steven E. Martin, John S. Green Facsm, Aaron F. Carbuhn, Stephen F. Crouse Facsm

International Journal of Exercise Science: Conference Proceedings

Prediction of the Total Energy Cost of an Acute Bout of Resistance Exercise in Young Men and Women

Brad S. Lambert†, Steven E. Martin‡, John S. Green‡ (FACSM), Aaron F. Carbuhn†, Stephen F. Crouse‡ (FACSM). Department of Health and Kinesiology, Texas A&M University, College Station, TX (Sponsor S.F. Crouse)

ACSM currently recommends resistance training (RT) for each major muscle group at least 2 times per week with a traditional repetition range of 8-12 per set. Because many investigators as well as fitness professionals consider kcal expenditure when creating training protocols, energy costs during both RT and aerobic training must be …

Exercise Attenuates Ctgf Levels, Delaying The Onset Of Fibrosis In The Aging Left Ventricle, Claire N. Canon, Jong-Hee Kim, Sean M. Courtney, Brandon Macias, John M. Lawler

International Journal of Exercise Science: Conference Proceedings

Aging is associated with a progressive increase in collagen (i.e., fibrosis) in the aging heart. Fibrosis is associated with a stiffening of the heart and a decrease in heart function. Previous data (Kwak, 2008) showed that matrix metalloproteinase (MMP) activity in the aging heart is decreased linked to an elevation TIMP-1 (tissue inhibitor of MMPs-1); while exercise training increased TIMP-1 and reduced MMP expression. Connective tissue growth factor (CTGF) is an upstream inhibitor of TIMP-1 and is implicated in diabetes and heart failure. We hypothesized that exercise would decrease CTGF levels, thus reducing fibrosis in the aged left ventricle. Young …

Short-Term Changes In Ldl Density And Lipoprotein Particle Number In Trained Men After 3 Different Modes Of Exercise, Jonathan M. Oliver

International Journal of Exercise Science: Conference Proceedings

Short-Term Changes in LDL Density and Lipoprotein Particle Number in Trained Men After 3 Different Modes of Exercise Jonathan M. Oliver, Steven E. Martin, Shawn P. Glowacki, Wade Womack, John S. Green, FACSM, and Stephen F. Crouse, FACSM, Texas A&M University, TX 77843, (Sponsor: S. F. Crouse) PURPOSE: To determine the short-term changes in LDL density and lipoprotein particle number after three different modes of exercise in trained men. METHODS: Twenty seven subjects were randomly assigned to complete either (resistance [RE], endurance [EE], or combination resistance/endurance [CE]) exercise. Fasting blood samples were obtained 24 h before (baseline) and 24 h …

The Effects Of Exercise On Caspase-Independent Mitochondrial Proteins In Regards To Age-Related Apoptosis, Sean M. Courtney, Jong Hee Kim, Brandon R. Macias, Claire N. Canon, John M. Lawler

International Journal of Exercise Science: Conference Proceedings

Exercise may have protective factors in reducing oxidative stress, mitochondrial dysfunction and mitochondrial caspase-dependent apoptosis with aging. It is presently unclear whether the caspase-independent apoptosis via EndonucleaseG (EndoG) and Apoptosis Inducing Factor (AIF) translocation from the mitochondria to the nucleosome is effected by exercise in aging skeletal muscle. It is understood that in aging skeletal muscle EndoG and AIF do translocate from the mitochondria to the nucleosome. We hypothesize that exercise will attenuate the translocation of EndoG and AIF from the mitochondria to the nucleosome in aging white gastrocnemius muscle. Twenty-four Fischer Brown Norway rats were randomly assigned to four …

T-Lymphocyte Activation Is Not Affected By The Mobilization Of Senescent T-Cells Into The Peripheral Blood Following An Acute Bout Of Exercise, David B. Bartlett, Cormac Cosgrove Dr, Guillaume Spielmann, Keith Guy Dr, Richard J. Simpson

International Journal of Exercise Science: Conference Proceedings

It is well recognized that individuals are at an increased risk of illness following an arduous exercise regime. Exercise may affect activation status of cells and play a pivotal role in defense against pathogenic invasion. CD69 is the earliest known expressed cell surface antigen of T-cell activation and is a reliable marker of cell activation status (Green et al. Med. Sci. Sports Exerc. 35, 582-588: 2003). Exercise is known to alter the frequency of senescent cells in the blood expressing the cell surface glycoprotein killer cell lectin-like receptor G1 (KLRG1), and are antigen-experienced and unable to clonally expand upon further …

Does Endurance Training Modify The Decrease In Skeletal Mass And Changes In The Body Composition With Restricted Caloric Intake?, Samantha M. Manning

International Journal of Exercise Science: Conference Proceedings

The common practice among many, including athletes and military personnel, when attempting to lose weight is to limit caloric intake and also to burn off excess calories through exercise.

Our goal was to measure the effects of graded reductions of energy availability on bone mass and body composition in young adult female rats. Reduced energy availability was achieved by increasing exercise energy expenditure and/or reducing caloric intake. After acclimation, 72 rats (5-mo-old) were randomly assigned to one of 6 groups. ADLIB-EX and ADLIB-SED were fed AIN-93M ad lib. Energy restricted, exercised groups (ER20-EX & ER40-EX) and sedentary energy-restricted groups (ER20-SED …

The Effects Of A Nad(P)H Oxidase Inhibition On Matrix Metalloproteinases And Timp-1 In The Mdx Diaphragm, Jong-Hee Kim, Hyo-Bum Kwak, John M. Lawler

International Journal of Exercise Science: Conference Proceedings

Duchenne muscular dystrophy (DMD) is characterized by devastating muscle degeneration that includes oxidative stress, loss of contractile tissue, muscle weakness and increased fibrosis in respiratory muscles (e.g., diaphragm). The mdx mice diaphragm undergoes a progressive degeneration similar to that occurring in patients with DMD. We showed that apocynin, a NAD(P)H oxidase inhibitor, protects against reduction in diaphragm mass, oxidative capacity, and apoptosis. We hypothesized that apocynin (1.5mmol/L per day) would attenuate extramyocyte space and collagen content by ameliorating matrix metalloproteinases (e.g., MMP-2, MMP-9), tissue inhibitors of metalloproteinases (e.g., TIMP-1) and transforming growth factor-β (TGF-β) in the mdx diaphragm. Eight to …

Comparison Of Retrofit Facemask To Mouthpiece For Metabolic Measures And Flow Rates, Abhishek Kelkar, Kevin Kendrick, Daniel Chilek

International Journal of Exercise Science: Conference Proceedings

Comparison of Retrofit Facemask to Mouthpiece for Metabolic Measures and Flow Rates Kelkar, A., Kendrick, K., and Chilek, D. R. Department of Health and Kinesiology, Lamar University, Beaumont TX PURPOSE: To compare metabolic measures (VO2, VCO2) and flow rates (VE) between use of a retrofit preVent™ neoprene mask (MA) and mouthpiece (MP) with nose clip. METHODS: Thirty healthy subjects [males (n = 18, 22.0 ± 2.5 years) and females (n = 12, 25.0 ± 6.3 years)] underwent four different intensity stages; rest (R), low (L), moderate (M) and high (H). Each stage had two, six minute sub stages, one with …

Effect Of Unstable Base Of Support On Energy Expenditure Of Resistance Training Exercise, Jason P. Campbell, Kevin Kendrick, Daniel Chilek

International Journal of Exercise Science: Conference Proceedings

Effect of Unstable Base of Support on Energy Expenditure of Resistance Training Exercise

Campbell, J., Kendrick, K. and Chilek, D. R.

Department of Health and Kinesiology, Lamar University, Beaumont TX

PURPOSE: To determine the effect of an unstable base of support on energy expenditure of a short duration, moderate intensity circuit resistance exercise. METHODS: Participants were 1 female and 8 males (27.0±6.7 yrs.). Data collection included 2 conditions: 1) standing on inflatable balance discs (unstable) and 2) standing on the floor (stable). The order of each condition was counterbalanced and separated by at least one day. Duration of …

Long-Term Weight Gain In Response To High-Fat Feeding In Cd-1 Mice, Whitney Breslin, Kelley Strohacker, Katie C. Carpenter, Lisa Esposito, Brian K. Mcfarlin

International Journal of Exercise Science: Conference Proceedings

Background. Excessive weight gain is known to cause numerous health related consequences in humans and rodents. Due to ethical issues, it is not appropriate to cause weight gain in humans. From an experimental design prospective, murine models are often used to measure the effect of weight gain. Despite the validity of murine models, there is little published information concerning long-term weight gain when mice consume a high-fat (60% of calories from fat) diet. The purpose of this study was to examine weight gain during high-fat feeding in wild type CD-1 male mice. Methods. This study utilized data collected during the …

Effect Of Hatha Yoga On Stress And Recovery Of Female Collegiate Athletes, Pritha Sharma, Kevin Kendrick, Daniel R. Chilek Jr

International Journal of Exercise Science: Conference Proceedings

Effect of Hatha Yoga on Stress and Recovery of Female Collegiate Athletes

Sharma, P., Kendrick, K., and Chilek, D.

Department of Health & Kinesiology

Lamar University, Beaumont, TX

PURPOSE: To determine the acute effect of Hatha yoga participation on stress and recovery of collegiate female athletes (cross country, soccer and volleyball). METHOD: Twenty five healthy female athletes were randomly divided into two groups, experimental (Yoga, Y; n=14, age=19.3±1.3 years) and control (No Yoga, C; n=11, age=19.7±3.6 years). Hatha yoga was performed on four consecutive days, at 30-40 minutes per session, and consisted of breathing exercise, meditation, asanas/postures, sun salute, and …

A Descriptive And Comparative Study Of Physical And Performance Characteristics Of Ncaa Division Ii And Division Iii Softball Players., Nicole L. Dickson, Chuck Ruot, Melissa Madeson, Lindsay Edwards

International Journal of Exercise Science: Conference Proceedings

Abstract. Dickson, N., Ruot, C., Madeson, M., and Edwards, L. A descriptive and comparative study of physical and performance characteristics of NCAA Division II and Division III softball players.

Purpose: The purpose of this study was to describe and compare the physical and performance characteristics of Division II and III softball players. This research also aimed to collect physical and performance measurements to begin the establishment of normative data on college softball players

Methods: Participants included two teams of female varsity National College Athletic Association Division (NCAA) II (N=19) and III (N=16) student-athletes. Athletes were evaluated prior to the softball …

Frequency Influences The Regularity Of The Structural Variations Present In The Leg Swing Kinematics, Vladimir Ivkovic, Max J. Kurz

International Journal of Exercise Science: Conference Proceedings

The regularity of human motor patterns has been linked to age and disease states [1]. For example, the structural variations that are found in a rhythmical finger force task are less regular in the aged and individuals with Parkinson’s disease (PD) [1]. These observed changes represent an inability of the nervous system to integrate the motor-sensory information for the maintenance of a regular motor pattern [1,2]. Currently, it is unknown if the changes in regularity of the structural variations persist while performing a rhythmical motor task with the lower extremity, and if the frequency of the rhythmical pattern influences the …

The Effects Of Abdominal Strength On Firefighting Ability, Marcos A. Michaelides, Koulla M. Parpa, Barry Brown

International Journal of Exercise Science: Conference Proceedings

The purpose of this project was to identify the relationships between various fitness parameters such as: upper body muscular endurance, upper and lower body strength, flexibility, anaerobic power, abdominal strength, body composition and the performance on an “Ability Test” (AT) that includes a set of six simulated firefighting tasks. Ninety firefighters participated in this study (age 33.54 ± 6.95 years). Firefighting ability was determined based on the time of completion of the AT. Abdominal strength was determined on an isometric device (AbMed). Abdominal strength was significantly inversely correlated (r = -.54, p < .01) with the overall performance on the AT test indicating that higher the abdominal strength was associated with shorter time of completion of the AT. Abdominal strength was also related with high performance (shorter times) on all six individual simulated firefighting tasks. In addition, the results of the multiple regression demonstrated that abdominal strength had a significant effect on the overall time to complete the AT. Abdominal strength contributed significantly [t(53) = -2.94, p < .01] to the predictive power of firefighter’s time to complete the set of firefighting tasks as described in the AT test. The most common test to evaluated core fitness among firefighters was based on the performance on the sit-up test which measures muscular endurance rather than muscular strength. The results of this study demonstrated that abdominal strength might be a better contributor to firefighting ability than abdominal muscular endurance, as determined by the sit-up test. The results presented in this study are unique since the method used to assess abdominal strength was not previously implemented on firefighters.