Impact Of One Night Sleep Restriction On Autonomic Function And Heart Rate Variability In Recreational Cyclists, Amanda J. Becker

Senior Honors Projects, 2010-2019

Introduction: Sleep quality has been shown to influence autonomic function. The autonomic nervous system (ANS) responds to stressors by regulating key functions such as heart rate. Autonomic function can be monitored via heart rate variability (HRV). Athletes are prone to poor sleep quality due to psychological and physical stresses of training and competing. Our objective was to investigate the function of the ANS at rest and during exercise following a night of normal sleep (SLP+) and a night of restricted sleep (SLP-).

Methods: Subjects (n=9) completed a familiarization trial and two identical experimental trials under different sleep conditions: SLP- (3-hour …

Hematological Changes In Response To A Drastic Increase In Training Volume In Recreational Cyclists, Jessie Axsom

James Madison Undergraduate Research Journal (JMURJ)

Changes in blood volume contribute to improvement in oxygen utilization (VO2max) with chronic endurance exercise training. Although hematological changes resulting from long-term endurance training have been well documented, it has not been well established whether an increased volume of endurance training preferentially affects plasma volume or red blood cell volume. To answer this question, I studied seven female and four male recreational cyclists before and after exposure to drastic increases (632%) in training volume. Following the 10-week training period, the mean hematocrit (Hct) of the 11 subjects who completed the study significantly (p0.05) correlated with the change in self-reported weekly …

Validity And Reliability Of The Ymca Submaximal Cycle Test Using An Electrically Braked Ergometer, Justin Kidd

Senior Honors Projects, 2010-2019

Purpose: To test the effect of using an electrically braked ergometer on the validity and reliability of the YMCA submaximal cycle test.

Methods: 22 male and 13 female subjects ages 19 to 31 completed one maximal treadmill test and four submaximal cycle tests to measure and estimate VO_2max, respectively. The maximal tests involved recording heart rate and VO₂ during graded exercise until volitional fatigue; an actual max was verified when two out of the following criteria: respiratory Exchange Ratio > 1.1, VO₂ plateau (< 150 ml/min increase in VO₂ during final stage), and achievement of 90% age-predicted HR max (or completed …

Physiological And Anthropometric Profiles Of Elite Teen-Age Cyclists, David Lenzi

Masters Theses, 2010-2019

Lenzi D. N., N. D. Luden, C. J. Womack, and M. J. Saunders. Physiological and anthropometric profiles of elite teen-age cyclists. Purpose: Previous research has demonstrated that maximal oxygen consumption (VO2max), lactate threshold (LT), aerobic/anaerobic power output, and several anthropometric characteristics are related to elite cycling performance in adults. These values also improve during maturation in children. However, there is little research examining how these values differ between elite teen-age cyclists and their adult counterparts. Previous literature has also reported low bone mineral density (BMD) in adult cyclists when compared to recreationally active controls. This study sought to characterize the …

Circulating Microrna Following High Intensity Interval Cycling With And Without Post-Exercise Nutrient Consumption, Jeremy Via

Masters Theses, 2010-2019

Introduction: MicroRNA (miRNA) are small, non-coding RNA that act post-transcriptionally to regulate gene expression. miRNA levels are modulated by acute aerobic exercise, yet little is known about how miRNA levels may change in response to high-intensity interval exercise. Further, almost nothing is known about the impact of post-exercise nutrition (carbohydrate and/or protein) on miRNA levels. Thus, the purpose of this study is to examine the effects of high-intensity interval cycling and different post-exercise nutrients on ci-miRNA levels. Methods: Nine recreationally active males (age 21.9 ± 2.0yrs; VO_2max 49.6 ± 4.0mL/kg/min) competed three trials, each including identical exercise protocols. Protocol …

Repeatability Of The Heart Rate Variability Threshold During Treadmill Exercise, Shane Chambers

Senior Honors Projects, 2010-2019

Purpose: Heart rate variability threshold (HRVT) is a clinical parameter used to gain insight into autonomic balance. Various studies have validated the use of cycle ergometers in determining HRVT, although the literature lacks evidence that treadmill use is a viable means of determining this threshold. We examined the repeatability of HRVT occurrence using standard deviation of normal R-R intervals (SDNN), root mean square of successive differences of continuous R-R intervals (RMSSD), and standard deviation of instantaneous beat intervals (SD1) in college aged males using treadmill exercise to see if this is a reliable method of threshold determination.

Methods: Ten healthy, …

The Quadriciser’S Effect On Range Of Motion And Upper Body Motor Control In Children With Mixed Quadriplegia Due To Chromosomal Disorders, Jillian P. Serigano

Senior Honors Projects, 2010-2019

PURPOSE: The purpose of this experiment is to determine the effects that the quadriciser has on range of motion and upper body motor control in children with mixed quadriplegia due to chromosomal deletion disorders. METHODS: Two subjects with different chromosomal deletion disorders participated in this study. They completed a 10-week passive exercise intervention using the quadriciser. Range of motion of the elbow and shoulder were taken pre and post quadriciser use for both subjects. For one subject, hip and knee measurements were also taken. Both subjects also completed a timed reach task pre and post quadriciser use to test motor …

The Effect Of Incline On Caloric Expenditure Measured By A Wrist-Worn Commercial Activity Monitor, Kaitlin M. Bickel

Senior Honors Projects, 2010-2019

Purpose Physical activity monitors have become popular among the general public to monitor steps, floors climbed, active minutes, and energy expenditure (EE). While there is evidence to support that these devices are accurate in counting steps, there is limited and inconclusive research regarding how accurate they are in measuring EE. This study aimed to test the accuracy of a newer commercial physical activity monitor, the Fitbit Charge (FC), in reporting EE compared to a research-grade accelerometer (GT3X), and indirect calorimetry (IC) while walking on a treadmill with and without incline.

Methods 30 subjects (22 female and 8 male) walked on …

Turning The Tables: A Student’S Study Into The Frequency Of Physical Activity Among University Faculty And Staff, Julianna M. Detrane

Senior Honors Projects, 2010-2019

The purpose of this study was to examine the relationship between physical activity and gender, position, social support, and motivation. The researcher conducted an observational, cross-sectional study of James Madison University faculty and staff (n=423) through the use of SurveyPlanet. The survey was adapted from the 2002 International Physical Activity Questionnaire (IPAQ), and participants responded to items regarding their current moderate and vigorous physical activity level based on the previous seven days, as well as items assessing level of motivation and sources of social support. Results of a multiple regression analysis, F(4, 412) = 6.811, p < .001, adj. R² = …

The Effect Of Menstrual Phase And Oral Contraceptive Steroids On Caffeine During Cycling Performance, Annette M. Lemanski

Masters Theses, 2010-2019

PURPOSE: There is evidence that female sex hormones impact caffeine metabolism, with decreased CYP1A2 activity and diminished caffeine clearance in women with higher estrogen levels. Therefore, the objectives of this project were to determine the effects of oral contraceptives and menstrual cycle on the benefits of caffeine supplementation for cycling performance. METHODS: Sixteen recreationally trained female cyclists, oral contraceptive steroid (OCS) users (n=8, age = 21.4 ± 1.4 years, height = 168.4 ± 3.6 cm, weight = 63.6 ± 7.2kg, VO_2max = 48.0 ± 4.0 ml/kg/min), and non-users (n=8, age = 20.9 ± 2.1 years, height = 161.0 ± …

The Impact Of Freedson Bout Vs. Non-Freedson Bout Physical Activity On Metabolic Syndrome Risk In College Students, Valerie Olijar

Masters Theses, 2010-2019

Purpose The aim of this study is to examine moderate to vigorous physical activity in Freedson bouts compared to non-Freedson bouts and their association with Metabolic Syndrome risk factors in college students.

Methods 72 subjects aged 18-26 were recruited from James Madison University. Subjects height, weight, waist circumference, blood pressure, and body composition were assessed on visit 1. Blood pressure, fasted blood glucose, and lipid profile were assessed on visit 2. Subjects wore an Actigraph GT3X+ accelerometer, which measured physical activity and sleep for 7 days and nights. Univariate Pearson correlation analyses were performed to determine the relationship physical activity …

Impact Of Pre-Exercise Feedings With A Low Or High Glycemic Index On The Ergogenic Effects Of Carbohydrate Mouth-Rinsing During Cycling, Nikolai J. Hladick

Masters Theses, 2010-2019

Purpose: Carbohydrate (CHO) ingestion during exercise enhances performance in short endurance events (~ 1 hr) due to neural influences, as demonstrated by the efficacy of CHO mouth-rinsing during cycling. However, the magnitude of these neural effects may be blunted following pre-exercise CHO feedings. This study examined whether the glycemic index (GI) of a pre-exercise meal affected time-trial (TT) performance in cyclists using a CHO mouth-rinse during exercise. Methods: Eight cyclists (age: 24 ± 6 yr; VO_2max: 61 ± 8 ml×kg^-1×min^-1) completed 4 exercise trials, consisting of 15 min of constant-load cycling followed by a …

The Hemostatic Effects Of Acute Exposure To Colored Cornstarch Powder During A 5k Run, Robert C. Allsbrook

Senior Honors Projects, 2010-2019

PURPOSE: To examine the acute hemostatic effects of particulate matter (PM) in the form of colored corn starch powder during a 5 kilometer race. METHODS: 10 recreationally active adults completed two 5k runs, one with color and one without color. 10 mL blood samples were taken 6 hours prior to the trial and immediately following the trial. PAI-1 activity, FVIII antigen, and tPA activity were measured using an ELISA. RESULTS: No significant main effects or interaction effects (P<0.05) were observed among any of the variables although a trend (P = 0.082) was observed for increased PAI-1 activity during exercise in the color condition. CONCLUSIONS: There is a trend towards increased PAI-1 activity levels during exercise during color runs that could be due to increased inflammation. Furthermore, the lack of increased FVIII:ag and tPA activity suggests that the intensity of the exercise may not have been adequate and further research should be conducted in this area.

Hematological Changes In Response To A Drastic Increase In Training Volume In Recreational Cyclists, Jessie E. Axsom

Senior Honors Projects, 2010-2019

Changes in blood volume contribute to improvement in VO2max with chronic endurance exercise training. Although hematological changes to chronic endurance training have been well documented, it has not been well established whether an increased volume of training in trained individuals preferentially affects plasma volume vs. red cell volume. To answer this question, we studied 8 female and 3 male recreational cyclists before and after exposure to drastic increases in training volume. Following the 10-week training period, mean Hct of the 10 subjects who completed the study significantly (p<0.05) increased from 42.9% to 48.45%. Mean Hb also increased significantly (p<0.05) from 14.6g/dL to 16.4 g/dL. The changes in Hct and Hb were not significantly (p>0.05) correlated with the change in self-reported weekly mileage (R = 0.13 …

Macronutrient Supplementation For Endurance Athletes, Jonathan B. Hurst

Senior Honors Projects, 2010-2019

Purpose: The present study addressed two questions related to macronutrient supplementation during endurance exercise. Firstly, the effects of carbohydrate and protein co-ingestion on time trial (TT) performance were compared to carbohydrate alone. Secondly, the effects of isolated protein ingestion on TT performance were compared to a placebo.

Methods: Six trained cyclists (Age: 22 ± 1 years; Height: 167 ± 12 cm; Weight: 60 ± 10 kg; VO_2max: 62 ± 7 ml/kg/min) completed four experimental trials, consisting of constant-load cycling for two hours (55% W_max) immediately followed by a 30-km simulated time trial. During the trials, subjects …

A 16-Week Run Sprint Interval Training Does Not Have An Effect On Cardiovascular Risk Measured By Framingham Risk Score On Prediabetic Women, Joan A. Mandelson

Masters Theses, 2010-2019

The Framingham risk score (FRS) was developed to determine the likelihood of developing cardiovascular disease (CVD) in the next 10 years using an individual’s age, gender, total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), smoking habits, and systolic blood pressure (SBP). Run-sprint interval training (R-SIT) has shown improvements in various health and blood markers while reducing total exercise time. To date there has not been a study that examines the effects of R-SIT and moderate intensity training (MIT) on framingham risk. The purpose of this study was to determine if a reduction of the 10-year risk of CVD (determined by …

A Low-Carbohydrate Ketogenic Diet Combined With Six Weeks Of Crossfit Training Improves Body Composition And Performance, Rachel M. Gregory

Masters Theses, 2010-2019

A low-carbohydrate ketogenic diet (LCKD) is a popular approach to weight and fat loss. CrossFit is a high-intensity power training (HIPT) type exercise for all levels of age and fitness that has gained recognition as one of the fasting growing sports in America. No previous research has been found which examines body composition changes or performance in individuals consuming a LCKD and participating in CrossFit training. PURPOSE: The purpose of this research was to examine the effects of a 6-week LCKD and CrossFit program on body composition and performance. METHODS: Twenty-seven non-elite CrossFit subjects (mean ± SD age = …

The Effect Of Sleep Restriction On Coagulation And Fibrinolysis After Heavy Exercise, Paul A. Roberson

Masters Theses, 2010-2019

Introduction: Research has shown exercise elicits a hemostatic response affecting coagulation and fibrinolysis. Furthermore, prior research has determined circadian fluctuations exist where clotting potential increases in the morning as a result of increased PAI-1 and decreased tPA which is further exacerbated by exercise. These circadian fluctuations and exercise responses have the potential to be accentuated by poor sleep. The purpose of this study is to determine the effects of sleep restriction on tPA activity, PAI-1 activity, and Factor VIII antigen activity (FVIII) while resting and after exercise.

Methods: 7 Subjects underwent two similar exercises sessions (EX). EX1 occurred in the …

The Influence Of Time-Of-Day Consumption And Training Status On The Ergogenic Properties Of Caffeine, James C. Boyett

Masters Theses, 2010-2019

Purpose: The objectives were to determine the effects of time-of-day consumption and training status on the benefits of caffeine supplementation for cycling performance and peak muscle strength. METHODS: Twenty untrained and trained subjects completed four trials consisting of isokinetic peak torque testing and 3-km time trials (TT). Subjects ingested either 6 mg/kg of caffeine or a placebo one hour prior to each trial. Treatments were: morning + placebo, morning + caffeine, evening + placebo, evening + caffeine. Magnitude based inferences were used to evaluate treatment differences. RESULTS: Caffeine (‘very likely’ and ‘likely’) improved 3-km TT performance in the morning and …

A Single Night Of Sleep Restriction Impairs Recovery From Heavy Exercise, John D. Chase

Masters Theses, 2010-2019

We examined the effects of one night of sleep restriction (Sleep-; 2.5 hrs) on subsequent 3-km cycling performance and skeletal muscle recovery from heavy exercise compared to a full night of rest (Sleep+; 7 hrs). Seven recreational cyclists (n=6 male, n=1 female; age = 24.4 ± 7 yrs; height = 170 ± 10 cm; weight = 68 ± 13 kg VO_2max = 61.5 ± 4.4 ml/kg/min) completed four simulated 3-km time trials (TT) and six peak isokinetic torque trials at different speeds (30 and 120°/sec) under both conditions. The first exercise trial (EX1) consisted …

Effect Of Carbohydrate Intake On Pacing In Endurance Cycling, Morgan A. Price

Senior Honors Projects, 2010-2019

PURPOSE: To study the influences of carbohydrate intake (CHO) on pacing in endurance cycling, as well as the effects of wearing metabolic headgear (HG) on power output. METHODS: Eight male endurance trained cyclists completed 120 min of constant load cycling at 55% W_max, immediately followed by a simulated 30 km time trial, on two occasions. On one occasion, subjects consumed a CHO solution at regular intervals throughout the trial, while a placebo (PL) was consumed during the other trial (in a randomly counterbalanced design). For statistical analysis, the 30 km time trial was divided into 4 segments (S1 …

The Effect Of Run Sprint Interval Training On Prediabetic Adults: Health Related Quality Of Life, Perceived Enjoyment, And Exercise Adherence, Nicole M. Gilbertson

Masters Theses, 2010-2019

Abstract

Purpose: The purpose of this study is to determine if Health Related Quality of Life (HRQOL) and perceived exercise enjoyment are greater in a run sprint interval training (RSIT) group compared to a moderate intensity training (MIT) group in sedentary, prediabetic adults after an 8-week intervention.

Methods: Over 8-weeks, subjects in the RSIT group progressed from 4 to 6 30-second sprints per session, and the MIT group progressed from 30 to 60 minutes of continuous moderate intensity exercise. Participants in both groups completed 8-weeks of the Centers for Disease Control and Prevention (CDC) Diabetes Prevention Program educational classes. HRQOL …

The Effect Of Run Sprint Interval Training On Diabetic Metabolic Markers In Prediabetic Adults, Kathryn L. Hilovsky

Masters Theses, 2010-2019

Abstract

Purpose: The primary purpose of this study was to compare the effects of an 8-week run-sprint interval training (R-SIT) and continuous moderate-intensity training (MIT) on fasting blood glucose, HbA1c, insulin sensitivity, and β-cell function in sedentary, prediabetic adults. Secondary outcomes of the study included anthropometric, body composition variables, and aerobic capacity.

Methods: Sedentary, physician diagnosed prediabetic individuals were randomized into R-SIT (n=7, BMI 36.76 ± 9.79) or MIT (n=8, BMI 40.59 ± 12.49) interventions. Subjects participated in supervised exercise three times a week and attended a Diabetes Prevention Program course, once weekly. R-SIT participants performed 4-6 x 30-second …

Satellite Cell Behavior In Cyclists Following Intensified Training With And Without Protein Supplementation, Alec I. Mckenzie

Masters Theses, 2010-2019

PURPOSE: The objectives were to determine the satellite cell (SC) response among endurance-trained cyclists (n=8; VO_2max: 63.1 ± 8.4 mL/Kg/min)to a period of intensified training (ICT) (10 days) and 10 days of recovery (RVT), with and without protein supplementation. METHODS: Muscle biopsies were obtained from the vastus lateralis prior to- and immediately following ICT and RVT. Fluorescent microscopy was used to analyze SCs and myosin heavy chain I and IIa (MHC I and IIa). Data were analyzed using magnitude-based inferences. RESULTS: MHC I SCs were exceptionally abundant at baseline (38 ± 20 SCs/100 fibers). MHC I SC count …

The Association Between Sleep Quality, Physical Inactivity, And Risk Of Developing Metabolic Syndrome, Matthew Scott

Masters Theses, 2010-2019

Abstract

Purpose The aim of this study is to assess the independent effects of sedentary time, sleep quality, and physical activity on risk factors for Metabolic Syndrome (MetS) in college students.

Methods 40 college aged students were recruited from James Madison University. Height, weight, blood pressure, waist circumference, and body composition were assessed on visit 1. Blood pressure, blood glucose, and lipid profile were assessed on visit 2. Subjects were required to wear an Actigraph GT3x accelerometer, which measured physical activity, sedentary time, and sleep quality for 7 days and nights. Univariate Pearson correlation analyses were performed to determine the …

The Effects Of Sr2w-1 Supplementation On Cycling Performance And Muscle Fatigue, Tara Ali Ata

Masters Theses, 2010-2019

The purpose of this investigation was to examine the potential effects of SR2W-1 supplementation on cycling performance, central fatigue, and a variety of physiological parameters, including blood lactate, blood pH, heart rate (HR), rating of perceived exertion (RPE), oxygen consumption (VO2), expired ventilation (VE), and respiratory exchange ratio (RER). Methods: Five recreational cyclists (38 ± 8 yr, 168.4 ± 4.3 cm, 68.8 ± 5.6 kg, and 54.4 ± 2.6 mL/kg/min) performed 20-min of steady-state cycling (~85% VO2max) followed by three 1-min high intensity intervals at VO2max with 30-sec active recovery periods at 100 W, 15-min passive recovery period, and a …