Exercise Science Commons^™

The Effect Of Acute Caffeine Withdrawal On Exercise Performance In Habitual Caffeine Users, Timothy D. Griest

Masters Theses, 2020-current

Purpose: The purpose of this study was to investigate how exercise performance is impacted by acute withdrawal from caffeine (CAF) in habitual users and if CAF ingestion will reverse the negative impact of withdrawal or have a net positive benefit. Methods: Ten recreational cyclists (age 39.1 ± 14.9 y; VO_2max 54.2 ± 6.2 mL/kg/min) who were habitual CAF consumers (394 ± 146 mg/d) completed four trials, each consisting of peak isokinetic torque testing and a 10-km time trial (TT). On each trial day, subjects consumed either 1.5 mg/kg CAF to prevent withdrawal or placebo (PLA) 8 hours before their …

Expiratory Flow Limitation In Elite Youth Cyclists, Katherine R. Smith

Masters Theses, 2010-2019

Expiratory flow limitation (EFL) has been reported in pre-pubescent adolescents and elite, adult endurance athletes; however, the occurrence of EFL in elite adolescent endurance athletes has not been determined. Purpose: To determine incidence and severity of EFL in elite youth male cyclists of adolescent age. We hypothesized that elite, endurance trained youth will experience a higher prevalence and severity of EFL and dyspnea compared to an untrained control group. Pulmonary function will be similar pre- to post-exercise with bronchodilation occurring in both groups. Methods: 12 elite endurance- trained (ET) youth male cyclists (16.3 ± 1.0 years; 176.5 ± …

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 …

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 …

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 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 …

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 …