Physiology Commons^™

Manuscript Has Been Retracted, Michael Smith, Nicholas Hanson, Alexander Lucas, Steven Devor

International Journal of Exercise Science

International Journal of Exercise Science 6(3) : 236-241, 2013. Manuscript has been retracted.

The Effect Of Cardiovascular Drift On The Efficacy Of Exercise Prescription, Katherine G. Forester, Jimmy Smith, Scott P. Mclean

International Journal of Exercise Science: Conference Proceedings

TACSM Abstract –

The Effect of Cardiovascular Drift on the Efficacy of Exercise Prescription

KATHERINE FORESTER, JIMMY SMITH, Ph.D., and SCOTT MCLEAN, Ph.D.

Kinesiology; Southwestern University; Georgetown, TX

Category: Undergraduate

ABSTRACT

Due to the difficulty in measuring metabolic cost in the field, heart rate (HR) is often used to prescribe exercise intensity. Purpose: To examine the effect of cardiovascular drift (CV_drift) on the efficacy of exercise prescription (ExRx). Methods: Eight women with a mean (sd) age 21.6(2.0) years, body mass 70.9(11.0) kg, height 163.7(6.0) cm, and VO₂max of 33.7(4.2) mL/kg/min, each performed two cycling trials for …

Effects Of Exercise Training On Cardiovascular Risk And Anti-Risk Factors In Adolescent Boys, Majid Koozehchian, Farzad Nazem, Mohmmad Panamtash, Brittanie Lockard, Richard Kreider

International Journal of Exercise Science: Conference Proceedings

Adolescence is a critical period in the formation of cardiovascular risk factors. Long-term exercise training has been found to be reversely related to risk factors levels in adolescents.

PURPOSE: To determine the effects of training (swimming and soccer) over a twelve week timeframe on some cardiovascular risk and anti-risk factors in adolescent boys.

METHODS: Forty two boys, including swimmers (SW n=14), soccer players (SO n=13), and a control group (C n=15) (Age=11.8±1.38yrs; Ht=149±.8.38cm; Wt=40±7.8kg) volunteered for this study. Fasting blood samples were obtained prior to initiation of training, at weeks 4, 8, and 12. A 3×4 repeated measures ANOVA with …

Physiological Markers Of Phase Change In Heart Rate Response To Work, Ashleigh Welter, Cory Scott, Frank Wyatt

International Journal of Exercise Science: Conference Proceedings

Heart rate response to increasing workload is accompanied by a series of physiologically marked stages, which can be identified through a linear and logarithmic regression line cross-over. These stages represent the withdrawal and activation of neural, hormonal and reflex mechanisms. However identification of physiological mechanisms associated with rate change is lacking in the literature. PURPOSE: The purpose of this study is to establish mathematical regression trend-lines for segmental changes in heart rate response to increased work, and identify the physiological mechanisms associated with said change. METHODS: Ten (n=10) male cyclists acted as subjects. Each signed a university approved …

Determination Of Anaerobic Threshold By Heart Rate Or Heart Rate Variability Using Discontinous Cycle Ergometry, Sung W. Park, Michael T. Brenneman, William H. Cooke, Alberto Cordova, Donovan L. Fogt

International Journal of Exercise Science: Conference Proceedings

We evaluated whether changes in heart rate (HR) and/or heart rate variability (HRV) would reflect anaerobic threshold (AT) using a discontinuous, incremental, cycle test. To accomplish this, exercise thresholds were determined for HR and HRV metrics and compared with AT via ventilatory threshold. Experienced cyclists (30.6±5.9y; 7 males, 8 females) completed a discontinuous cycle test consisting of 7 stages (6 min each with 3 min of rest between). Three stages were performed at W below AT, one at AT, and 3 above AT. The averaged stage data for Ve, HR, and time- and frequency-domain HRV metrics were plotted versus W. …

Carotid Baroreflex Control Of Heart Rate Is Enhanced During Whole-Body Heat Stress, Davor Krnjajic, Cory L. Butts, Mitchel R. Samels, Shane W. Warren, Tyler J. Benson, Keller M. David

International Journal of Exercise Science: Conference Proceedings

Whole-body heat stress (WBH) reduces orthostatic tolerance. While impaired carotid baroreflex (CBR) function during WBH has been reported, study design considerations may limit interpretation of previous findings. We sought to test the hypothesis that CBR function is unaltered during WBH. CBR function was assessed in ten subjects using 5-sec trials of neck pressure (45, 30 and 15 Torr) and neck suction (-20, -40, -60 and - 80 Torr) during normothermia (NT) and passive WBH (Δ core temp ~1 °C). Analysis of stimulus response curves (4-parameter logistic model) for CBR control of heart rate (CBR-HR) and mean arterial pressure (CBR-MAP), as …

Lactate Concentration Response To Knee Extension Exercise With Various Initial Restrictive Pressures In Females, Joe-Angel Lopez B.S., Guillermo Perez B.S., Murat Karabulut Phd, Cscs

International Journal of Exercise Science: Conference Proceedings

Literature remains lacking in regards to the role that initial restrictive pressure (IRP) coupled with resistance training as it pertains to the production and accumulation of metabolic byproducts such as lactate, more specifically in women. Purpose: The present study investigates the importance of the IRP as a variable on lactate concentrations during knee extension exercise in combination with blood flow restriction in female subjects. Methods: Thirteen female volunteers (age 21± 1.35) served as the test sample for this study. Initial health screening, PAR-Q, signing of the informed consent, procedural and dynamometer setting familiarization were completed on the first meeting. Prior …

The Effect Of Age And Exercise Training On Endothelial Function And Protein:Protein Interactions Among Enos And Its Regulatory Proteins In Rat Aortas, Meredith J. Luttrell, John Seawright, Christopher R. Woodman

International Journal of Exercise Science: Conference Proceedings

Previous studies indicate that nitric oxide (NO)-mediated endothelium-dependent dilation declines with age. PURPOSE: The purpose of this study was to test the hypothesis that impaired NO-mediated, endothelium-dependent dilation in aged arteries is due to age-related alterations in protein:protein interactions among endothelial nitric oxide synthase (eNOS) and its regulatory proteins, resulting in reduced NO production in aged arteries. The regulatory proteins of interest in this study are Caveolin-1 (Cav1), an inhibitor of eNOS enzyme activity, and Heat-shock protein 90 (Hsp90), which enhances eNOS activity. METHODS: Young (2 mo) and Old (22 mo) male Fischer 344 rats were endurance exercise trained on …

Relationship Between Arterial Stiffness And Cerebral Vascular Reactivity In College-Aged African Americans, Chansol Hurr

International Journal of Exercise Science: Conference Proceedings

African Americans (AA) have increased risk for cardio and cerebral vascular disease relative to Caucasians (CA). While is it generally accepted that arteries become stiffer at a younger age in AA; less is known regarding cerebral vascular function / reactivity (CVMR) to hypercapnia in AAs. Furthermore, to our knowledge, little is known regarding the relationship between arterial stiffness and CVMR, particularly in young healthy adults. We tested the hypothesis that AAs have elevated arterial stiffness and reduced CVMR during hypercapnia relative to CAs. Furthermore, we hypothesized that there would be a negative relationship between arterial stiffness and CVMR. In 7 …

Cardiorespiratory And Biomechanical Responses To Simulated Horseback Riding In Healthy Children, Brandon R. Rigby, Zacharias Papadakis, Annie Bane, Jin Park, Peter Grandjean

International Journal of Exercise Science: Conference Proceedings

TACSM Abstract

Cardiorespiratory and biomechanical responses to simulated horseback riding in healthy children

B RHETT RIGBY, ZACHARIAS PAPADAKIS, ANNIE A BANE, JIN K PARK, and PETER W GRANDJEAN

Baylor Laboratories for Exercise Science and Technology; Department of Health, Human Performance, and Recreation; Baylor University; Waco, TX

Category: Doctoral

ABSTRACT

The movement of specific body segments during horseback riding is similar to common physical activities such as walking. Yet, little is known regarding the cardiovascular responses to horseback riding (HBR) which may be due to how difficult it is to quantify the physical work of HBR. The purpose of this study …

Skin And Cerebral Vascular Function / Reactivity In Healthy Young Adult African Americans, Kiyoung Kim

International Journal of Exercise Science: Conference Proceedings

African Americans (AA) are at an increased risk for cardio and cerebral vascular disease relative to Caucasians (CA) and the underlying impairments manifest as early as the second generation prior to overt signs of risk. The mechanisms of this increased risk are multifactorial; however, evidence suggests that microvascular dysfunction is a primary contributor. This study tested the hypothesis that microvascular function, indexed by the skin vascular conductance (SkVc) response to local heating, is impaired in young otherwise healthy AAs. Furthermore, we hypothesized that AAs have an attenuated cerebral vasodilator response to hypercapnia. To date complete data sets have has been …

Association Of Cardiovascular Fitness And Metabolic Syndrome In Male Police Officers, Matthew S. Schmidt, Steve Martin

International Journal of Exercise Science: Conference Proceedings

Metabolic syndrome has been shown in numerous studies to be related to a higher incidence of coronary artery disease (CAD). A study by Jurca and coworkers (Med. Sci. Sports Exerc 36(8):1301-1307, 2004) found a relationship between aerobic fitness and the prevalence of metabolic syndrome in a group of men enrolled in the Aerobics Center Longitudinal Study (ACLS). In addition, recent work in our lab (Int J Exerc Sci 2(1): S43, 2009) has supported these findings. However, research exploring this relationship is still lacking in male police officers. Previous research has suggested that the prevalence of CAD in police …

Association Of Cardiovascular Fitness And Syndrome X In Male Firefighters, Adam C. Sanchez, Steven E. Martin, Brad S. Lambert, Alex Carradine, John S. Green Facsm, Steve F. Crouse Facsm

International Journal of Exercise Science: Conference Proceedings

Metabolic syndrome has been shown in numerous studies to be related to a higher incidence of coronary artery disease. A study by Jurca and coworkers (Med. Sci. Sports Exerc 36(8):1301-1307, 2004) found a relationship between cardiovascular fitness and the prevalence of metabolic syndrome in a group of men enrolled in the Aerobics Center Longitudinal Study (ACLS). In addition, recent work in our lab (Int J Exerc Sci 2(1): S43, 2009) has supported these findings. However, research exploring this relationship is still lacking in male firefighters, whose leading cause of line-of-duty deaths is heart attacks. Purpose: To further …

Association Of Venous Function And Post-Exercise Oxygen Consumption, Eric Tisdell, Matthew C. Scott, Zeki Bahadir, Tracie Parish, Arturo Arce-Esquivel, Devon Dobrosielski, Michael Welsch

International Journal of Exercise Science

International Journal of Exercise Science 6(1) : 63-73, 2013. Excess post-exercise oxygen consumption (EPOC) has been attributed to metabolic, hemodynamic, neuroendocrine, and pulmonary factors. Interestingly, few studies have examined the role of venous system on EPOC. The purpose of this study was to examine the relationship between measures of vascular function and EPOC. Measures of vascular function and VO₂ recovery kinetics were examined in 20 individuals [age=22+2.41 yrs]. Nondominant forearm arterial inflow, venous capacitance and venous outflow were evaluated at rest and after 5 minutes of upper arm occlusion, using strain gauge plethysmography. VO₂ recovery kinetics was assessed …