UNT Libraries - 18 Matching Results

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Critical Power as a Predictor of Performance in a Bicycle Time Trial

Description: Certain measures of aerobic power have been shown to have a high relationship with endurance performance. Critical power (CP) has also been shown to be well correlated to endurance performance, but few studies have evaluated its use in a competitive scenario. In this study, cardiorespiratory-metabolic measures were evaluated in 13 highly trained cyclists to determine their relationship to performance in a 17 km time trial. Critical power, determined from the nonlinear power-time model, was also evaluated to determine its relationship to performance in a 17 km time trial. Results indicate that the traditional indicators of V02max and ventilatory anaerobic threshold were well correlated to TT performance (r=-0.86, r=-0.79, respectively). The principal finding from this study was that performance in a bicycle time trial is related to CP at least as well as to cardiorespirator-ymetabolic measures. In fact, the results fromthis study suggest that the relationship between performance and CP is stronger (r=-0.89). Use of the critical power concept is attractive because testing requires only a cycle ergometer and a stopwatch to estimate a parameter of aerobic fitness.
Date: December 1994
Creator: Dangelmaier, Brian (Brian S.)

Ecological Analysis of Physical Activity and Health-related Quality of Life in Female College Students.

Description: Health-related quality of life (HRQOL) is a comprehensive construct including physical and psychosocial health functioning. Despite significant health benefits of regular physical activity (PA), over 40% of female college students do not meet recommended PA guidelines to improve their health. This study investigated the influences of individual, social, and physical environmental factors on students’ PA and HRQOL. Participants were 235 female university students who completed validated surveys assessing their perceptions of PA, HRQOL, and social ecological factors. Three hierarchical regressions revealed individual and physical environmental factors as predictors of PA and HRQOL. These findings indicated health professionals need to consider students’ individual factors and physical environmental factors to promote female students’ PA and HRQOL.
Date: December 2011
Creator: Dunn, Jacqueline

Effect of Resistance Training on Cytokines in Hiv+ Men with Chemical Dependence

Description: Human immunodeficiency virus (HIV) and substance abuse (drug and/or alcohol) independently impair the immune system; importantly, the combination of HIV infection and substance abuse might produce more than an additive effect on this system. Tumor necrosis factor-alpha (TNF-?) and Interferon gamma (IFN?) are pro-inflammatory cytokines involved in differentiation of Th0 cells into Th1 cells. Interleukin 4 (IL-4) and Interleukin 10 (IL-10) are anti-inflammatory cytokine involved in differentiation of Th0 cells to Th2 cells. Unbalanced Th1 and Th2 cells can lead to immune suppression. Thus, changes in these cytokines could have important implications for people infected with HIV (HIV+). Resistance training can counteract muscle wasting, improve strength, and improve muscle mass. The purpose of this study was to examine the effect of resistance training on resting concentrations of circulating TNF-?, IFN-?, IL-4, and IL-10. Sixteen men (42 ± 11 years, 180.4 ± 9.1 cm, 89.2 ± 20.7 kg) infected with HIV and enrolled in an intensive 60-day in-patient substance addiction/abuse treatment program were recruited shortly after admission to the treatment facility. Participants were assigned to one of two groups using randomization: supervised resistance exercise 3 times per week using a progressive and non-linear periodized program (Exercise) or no exercise training (Non-Exercise) for six weeks. Before (Pre) and after (Post) the 6-week period, resting and fasted blood samples were obtained and analyzed for serum TNF-?, IFN-?, IL-4, and IL-10 concentrations using a high-sensitivity ELISA. TNF-? did not change following the 6-week period for Exercise (Pre: 4.8 ± 2.7 pg·ml-1; Post: 4.6 ± 2.4 pg·ml-1) or Non-Exercise (Pre: 3.0 ± 1.3 pg·ml-1; Post: 2.7 ± 0.8 pg·ml-1). IFN-?, IL-4, and IL-10 concentrations were below detectable limits. No adverse effects of the intervention were reported. A six-week resistance training program does not elicit changes in circulating TNF-? concentrations in men infected with HIV and ...
Date: May 2012
Creator: Curtis, John Harper

The Effect of Season Performance on Male and Female Track and Field Athletes’ Self-identity

Description: Although the “self” has generally been conceptualized as relatively stable in sport-specific research, events such as deselection, injury, and career termination have been found to negatively affect athletes’ levels of identification with the athlete role. Additionally, there has been limited research regarding competitive failure and its ability to negatively affect athletes’ levels of identification with the athlete role. The purpose of the present investigation was to provide additional evidence regarding the influence poor competitive seasons have on the malleability of athletes’ self-identity. Athletes were followed throughout the course of their season to determine whether athletes who encountered a poor competitive season reported lowered levels of athletic identity. Specifically, male and female NCAA Division I track and field athletes completed pre-indoor, post-indoor, and post-outdoor assessments of athletic identity. Contrary to previous research, the current study’s results indicated no identifiable relationship between male and female athletes’ season performance satisfaction and their level of post-indoor and post-outdoor athletic identity. Thus, the greatest predictor of athletes’ post-season level of athletic identity was their pre-season level of athletic identity, regardless of season performance. Given these results, future research should assess self-esteem as well as other potential coping strategies athletes might use in order to gain a better understanding of the effect encountering a poor competitive season may have on athletes’ self-identity.
Date: August 2013
Creator: Bradstreet, Tyler C.

The Effects of a Psychosocial Environment on College Women’s Exercise Regulations and Social Physique Anxiety

Description: A positive psychosocial intervention comprised of high autonomy support, task-involvement, and caring was implemented in physical activity classes to examine its effects on college women’s basic psychological needs (i.e. autonomy, competence, relatedness), exercise regulations (i.e. external, introjected, identified, integrated, intrinsic) and social physique anxiety (SPA). We hypothesized that at the end of the semester, participants in the intervention group (N = 73) would report greater need satisfaction, more self-determined regulations and less SPA than participants in the non-intervention group (N = 60). At T1 and T2, both the intervention and non-intervention participants reported “agreeing” with experiencing an autonomy supportive, task-involving, and caring environment. Furthermore, both groups at T1 and T2 reported moderate SPA. No significant group differences were found at T1. At T2, significant group differences were observed in the intervention and non-intervention groups’ report of external regulation and intrinsic regulation. The results suggests that group exercise instructors are capable of creating a positive psychosocial environment to enhance students’ intrinsic motivation.
Date: May 2015
Creator: Alvarez, Ana

Effects of Maternal Aerobic Exercise on Selected Pregnancy Outcomes in Nulliparas

Description: This study evaluated the effects of participation in aerobic exercise on pregnancy outcomes. Pregnancy outcomes included type of delivery, length of labor, gestational age, neonatal birth weight, and maternal weight gain. The 137 nulliparas were categorized as active (N=44) or sedentary (N=93) based on self-reported aerobic exercise. Findings from this study suggest that pregnant women who were active during pregnancy were more likely to have vaginal deliveries than sedentary women. No significant differences between active and sedentary women were found in neonatal birth weight, maternal weight gain, length of labor, or gestational age.
Date: August 1997
Creator: Melgar, Dian L. (Dian Louise)

Factors Related to Meeting Physical Activity Guidelines in College Students: a Social Cognitive Perspective

Description: Engaging in regular physical activity is important for maintaining and improving health. Unfortunately, most college students fail to meet the recommendations for both aerobic and muscle-strengthening physical activity guidelines (PAGs). Psychosocial factors described within the social cognitive theory are related to the acquisition and retention of physical activity behaviors. The purpose of this study was to examine the relations of gender, self-efficacy, outcome expectancies, and social support with college students meeting aerobic, muscle-strengthening and both PAGs. Participants (N = 396) completed online questionnaires assessing their physical activity behaviors, exercise self-efficacy, outcome expectancies, and social support. Self-reported physical activity was classified as meeting / not meeting PAGs. Using gender, exercise self-efficacy, outcome expectancies, and social support as predictors, separate logistic regressions were used to examine their relations with the three PAG classifications. Analyses revealed that being male and level of social support increased the odds of meeting muscle-strengthening PAGs, but students’ level of self-efficacy and outcome expectations increased the odds of meeting all three PAG classifications. These findings indicate that interventions designed to increase self-efficacy and outcome expectancy may be beneficial for increasing college students’ physical activity for meeting the PAGs. Promotion of muscle-strengthening activities targeted at young women is also warranted.
Date: May 2014
Creator: Farren, Gene L.

Hormonal Response to Free Weight and Machine Weight Resistance Exercise

Description: No study has examined the effect of exercise modality (free weight vs. machine weight) on the acute hormonal response using similar multi-joint exercises. The purpose of this investigation was to examine the effect of resistance exercise modality on acute hormonal responses by comparing the squat and leg press which are multi-joint, and similar in action and lower-body muscle involvement. Ten resistance trained men (21-31 y, 24.7 ± 2.9 y, 179 ± 7 cm, 84.2 ± 10.5 kg) participated in the study. Sessions 1 and 2 determined the participants’ 1-RM in the squat and leg press. During acute heavy resistance exercise testing visits (AHRET), sessions 3 and 4, participants completed 6 sets of 10 repetitions with an initial intensity of 80% of their 1-RM for the squat and leg press exercises. There was a 2 minute rest period between each set. Blood samples were collected before, immediately after, and 15 and 30 minutes after exercise via intravenous catheter during the AHRET visits and were analyzed for testosterone, cortisol, and growth hormone. Lactate, plasma volume change, heart rates and ratings of perceived exertion were also measured. Total work was calculated for external load only and for external load and the body mass used in the exercises. The 4 sessions were counterbalanced and randomized for exercise mode. Testosterone for the squat (Pre: 23.9 ± 8.7 nmol•L-1; IP: 31.4 ± 10.3 nmol•L) and leg press (Pre: 22.1 ± 9.4 nmol•L-1; IP: 26.9 ± 7.8 nmol•L) increased but more significantly after the squat. Growth hormone increased in both the squat (Pre: 0.2 ± 0.2 µg/L; IP: 9.5 ± 7.3 µg/L) and the leg press (Pre: 0.3 ± 0.5 µg/L; IP: 2.8 ± 3.2 µg/L). The increase was significantly higher after the squat compared to the leg press. Cortisol also increased after performing the squat (Pre: ...
Date: August 2012
Creator: Shaner, Aaron Arthur

The Influence of Perceived Support From Parental and Peer Relationships on Students' Health-related Beliefs and Behaviors

Description: College is an important time for young adults, but most college students fail to meet the daily recommendations for physical activity. Social support is associated with positive health practices, but limited research is available on the role of perceived support from specific relationships, (e.g., peers and parents). The purpose of this study was to evaluate the effect of perceived support from parental and peer relationships on health-related beliefs and behaviors. Participants (N = 333) completed the Quality of Relationships Inventory, Multidimensional Scale of Perceived Social Support, Satisfaction With Life scale, and a short version of the Physical Self-Description Questionnaire. While highly active students did not necessarily have more socially support relationships, females self-reported more conflict with both parents and more depth and support with a special person in their life than males, and parental and peer relationships appeared to be a greater influence on females' perceptions of satisfaction and self-worth.
Date: May 2013
Creator: Barton, Mitch

Physiological and Psychological Effects of an Acute Stressor: Comparing Coping Strategies Among Very Physically Active and Less Active Adults

Description: The purpose of this study was to examine whether physical activity status of healthy adult males (N = 59) while in a coping strategy condition (association, disassociation, or control) influences psychophysiological responses to an acute painful stimulus. Measures of pain tolerance, state anxiety, body awareness, and salivary cortisol were investigated. Results indicated no significant differences between physical activity groups for pain tolerance, stress responses (i.e., self-reported state anxiety and cortisol levels), or body awareness. Though, those who indicated using a disassociation coping technique during the exit interview tolerated the acute, surface pain longer. More research is required to further understand the effects of physical activity and coping strategies on pain perception and psychophysiological responses.
Date: May 2014
Creator: Brandt, Grace A.

Predicting Peak Oxygen Uptake from Ratings of Perceived Exertion During Submaximal Cycle Ergometry

Description: The purpose of this study was to predict VO2pak using ratings of perceived exertion (RPE), heart rate (HR), and percent fat (PFAT). Subjects were males (n= 60) (PFAT, M SD = 14.4 6.1) and females (n= 67) (PFAT, M SD = 23.4 4.9) with ages ranging from 18 to 33 years. Subjects performed an incremental cycle ergometer protocol and RPE, HR and Vo2 were measured at each stage until VO2 ak was achieved. Mean RPE and HR at the submaximal workload of 100 watts were, (RPE100) M= 12.7 2.6 and (HR100) M= 146.924.7 respectively. Correlations (p< .001) with VO2p. were -.75 (PFAT), -.66 (HR100), -.67 (FIPE100). The multiple correlation using PFAT, HR100, and RPE100 as predictors of VO2pak was .83 (SEE= 5.28 ml-kg BW'smin"). Each predictor contributed to the correlation (p<.01). The results indicate that PFAT combined with exercise responses of RPE and HR provide valid estimates of VO2peak with a relatively small SEE.
Date: May 1992
Creator: Fairfield, Eric S. (Eric Scott)

Psychological Factors Related to Drug Use in College Athletes

Description: The purpose of the present investigation was to compare the psychological factors related to drug use by college athletes on seven drug categories. A questionnaire was given to male and female Division I college athletes asking them about their use of drugs. The frequency, intensity and duration of use/non-use was used to divide subjects into high and low/nonuser categories. Dependent measures included the Profile of Mood States, Coopersmith Self-Esteem Inventory and questions assessing athlete stress. A multivariate analysis of variance(MANOVA) was conducted in a 2 x 2 (alcohol high/low, non-user x male/female) design to distinguish significant differences on the POMS and stress questions followed by univariate ANOVA's. A separate ANOVA was run on Coopersmith's Self-Esteem Inventory. Results indicated that high alcohol users scored significantly higher on anger, fatigue and vigor than low/non-users. Significant differences were found between males and females on the pressure felt from coaches to perform well.
Date: August 1990
Creator: Evans, Melissa

Relationship Between Mood State and Cognitive Strategies on Endurance Performance

Description: The present investigation examined the relationship between elated and depressed moods and dissociation, association, and positive self-talk strategies on endurance performance. Results showed a significant mood main effect with elated subjects performing longer than depressed subjects. Results also revealed a significant cognitive strategy main effect with positive self-talk and dissociation groups producing longer endurance times than association and control groups. A significant interaction between mood and cognitive strategy found that subjects in the positive self-talk and dissociation groups increased their performance time to a greater extent from the depressed to the elated condition than did subjects in the association and control groups. Results are discussed in terms of previous investigations of mood and cognitive strategies on physical performance.
Date: December 1991
Creator: Litke, Lonnie D. (Lonnie Dale)

Reliability of an On-line System to Assess Physical Activity Behaviors in an Active Group of Kinesiology Undergraduate Students

Description: Engaging in muscle strengthening activities (MSA) as part of a physical activity program offers health benefits. Although the merits of physical activity are well documented, many adults fail to meet appropriate levels as recommended in the 2008 Physical Activity Guidelines for Americans (PAGA). To get a more complete understanding on an individual's physical activity behaviors, the Tracking Resistance Exercise and Strength Training (TREST) internet based survey was developed. The purpose of the current study was to determine the test-retest reliability of TREST items. Additionally, the prevalence of participants meeting the 2008 PAGA was reported by gender. The survey was completed approximately two weeks apart by 224 (52% male) undergraduate kinesiology students. Analysis of the survey items presented TREST as a reliable instrument in assessing an individual's physical activity behavior with a focus on MSA. Among the convenience sample of 445 participants (56% male) that completed the survey in assessment #1, 73% met the 2008 PAGA minimum recommendations for MSA (>=2 days/week) and aerobic activity (>= 150 min MVPA). A more complete MSA and MVPA criteria was established (requiring MSA of all seven major muscle groups) and only 32% of participants met this guideline. In general, men engaged in aerobic exercise and MSA more than women. These results cannot be generalized due the age, activity level, and education of the study's participants. Future studies should investigate the validity of TREST items among a sample of varying fitness levels, races/ethnicities, ages, and educational levels.
Date: August 2013
Creator: Knell, Gregory

Responses During Exercise at 90% and 100% of the Running Velocity Associated with VO2max (vVO2max)

Description: Six male long-distance runners participated in this study to evaluate the responses to exercise at 90% and 100% vV02max. Subjects participated in five maximal exercise tests: one incremental, three tests at 90% vV02max, and one test at 100% vV02max. The results of this study demonstrate that V02max can be elicited in a constant-velocity test at 90% vV02max.
Date: August 1995
Creator: Burt, Shane E. (Shane Eugen)

Self-Objectification and Sport Participation: Do the Gendered Makeup and Competitive Level of the Team Matter?

Description: The purposes of this study were to (a) investigate differences in self-objectification, self-surveillance, body shame, and flow among female athletes on all-women's and coed ultimate frisbee teams at different competitive levels, and (b) examine the objectification theory model across groups. Participants (n = 112) completed online surveys including a demographic questionnaire, trait and state versions of the Self-Objectification Questionnaire, Body Surveillance and Body Shame subscales of the Objectified Body Consciousness Scale, and the Flow State Scale. No differences in self-objectification, self-surveillance, or body shame were found, although highly competitive athletes experienced more flow than lower competitive teams. Relationships were found between self-objectification, self-surveillance, and body shame, but not for flow, partially supporting the objectification theory model.
Date: May 2010
Creator: Ede, Alison

Self-Objectification, Body Image, Eating Behaviors, and Exercise Dependence among College Females

Description: The purposes of this study were to examine the associations between (a) self-objectification, (b) body shame, (c) appearance anxiety, and (d) exercise dependence. Participants (N = 155) completed a demographic questionnaire and a survey packet including the Body Surveillance subscale and Body Shame subscale of the Objectified Body Consciousness Scale, Appearance Anxiety Scale, Eating Attitudes Test 26, and the Exercise Dependence Scale. Correlations were conducted revealing associations between self-objectification, body shame, appearance anxiety, and eating attitudes. Associations were also found between body shame and exercise dependence. Partial correlations were conducting revealing body shame and appearance anxiety mediated the relationship between self-objectification and eating attitudes. Body shame also mediated the relationship between self-objectification and exercise dependence.
Date: August 2010
Creator: Kessler, Kelly L.