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(1 - 12 of 12)
- Title
- EMG Biofeedback as a Generalized Relaxation Technique.
- Creator
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Cunningham, David, Abbott, David, Social Sciences
- Abstract / Description
-
University of Central Florida College of Social Sciences Thesis; Ten college students serving as volunteer subjects were randomly assigned to one of two groups . One group received EMG biofeedback training using feedback from the frontalis muscle only , and the other group received EMG biofeedback training using feedback from several muscle sites. It was hypothesized that subjects who were given EMG biofeedback relaxation training sequentially from several muscle sites would be able to lower...
Show moreUniversity of Central Florida College of Social Sciences Thesis; Ten college students serving as volunteer subjects were randomly assigned to one of two groups . One group received EMG biofeedback training using feedback from the frontalis muscle only , and the other group received EMG biofeedback training using feedback from several muscle sites. It was hypothesized that subjects who were given EMG biofeedback relaxation training sequentially from several muscle sites would be able to lower EMG levels at these sites to a significantly greater degree than subjects who received EMG biofeedback relaxation training using feedback from the frontalis muscle only. Both groups were given a pre-training baseline session, nine training sessions , and a post-training baseline session . Comparing the mean pre- training and post- training baseline EMG levels of each group at each muscle site using t -tests showed that there was no significant reduction of EMG muscle activity at any monitored muscle site due to either frontalis feedback training only or multiple muscle feedback training . This failure to obtain significant training effects may have resulted from using college students as subjects since they were not trying to relieve a stress related disorder and they exhibited low initial baseline EMG levels. It is suggested that future research on the generalization of EMG biofeedback training be done using a clinical population having elevated EMG levels.
Show less - Date Issued
- 1979
- Identifier
- CFR0003503, ucf:53009
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0003503
- Title
- Role of brain derived neurotrophic factor (BDNF) in stimulating strength improvements induced by short-term resistance training.
- Creator
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Church, David, Hoffman, Jay, Stout, Jeffrey, Fukuda, David, Stock, Matt, University of Central Florida
- Abstract / Description
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Strength adaptations from short-term resistance training are thought to be related primarily to neurological adaptations. Considering brain-derived neurotrophic factor (BDNF) role in the nervous system, it is possible that BDNF has a role in these adaptations. Fourteen untrained males were randomized into either a resistance training (RT; n =8) or control (CON; n=6) group. Motor unit (MU) recruitment at 50% and 80% of each participant's maximal voluntary isometric contraction (MVIC), muscle...
Show moreStrength adaptations from short-term resistance training are thought to be related primarily to neurological adaptations. Considering brain-derived neurotrophic factor (BDNF) role in the nervous system, it is possible that BDNF has a role in these adaptations. Fourteen untrained males were randomized into either a resistance training (RT; n =8) or control (CON; n=6) group. Motor unit (MU) recruitment at 50% and 80% of each participant's maximal voluntary isometric contraction (MVIC), muscle cross sectional area (CSA) and thickness (MT), as well as one-repetition maximum (1RM) of the squat (SQT), leg press (LP), and leg extension (LE) were performed before (PRE) and after (POST) the training period. Following the MU assessment, the recruitment threshold (RT; % MVIC) and mean firing rate (MFR; pulse per second [pps]) of each MU were determined. Linear regression was used to quantify the slope (pps/% MVIC) and y-intercept (pps) of the MFR versus RT relationship for each participant and time point. Participants completed an acute resistance exercise bout at PRE and POST consisting of 3 sets of 8 (-) 10 repetitions with 90 seconds of rest between each set of SQT, LP, and LE. Blood samples were obtained following a 4-hour fast before (BL), immediately-(IP), and one-(1H) hour post resistance exercise. RT subjects performed the same resistance exercise protocol at PRE twice a week for 3-weeks. CON subjects were instructed to not perform any resistance exercise. Area under the curve (AUC) analysis was determined by the trapezoidal method. Pearson product-moment correlations were used to examine selected bivariate relationships. The ?BDNF AUC was significantly correlated to the relative 80% ?y-intercept (r=-0.626, p=0.030), and trended to be correlated to the relative 80% ?slope (r=0.551, p=0.063). Our results indicate that ? in plasma BDNF concentrations appear to be related to ?'s MU recruitment at high intensities (80% of MVIC) of exercise.
Show less - Date Issued
- 2018
- Identifier
- CFE0006988, ucf:51665
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006988
- Title
- Measurement Of Negative Affectivity In Psychometrically Defined Schizotypy Using Facial Electromyography.
- Creator
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Mitchell, Jonathan, Cassisi, Jeffrey, Bedwell, Jeffrey, Beidel, Deborah, University of Central Florida
- Abstract / Description
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Schizotypy is a sub-threshold syndrome associated with schizophrenia. Much of the research on schizotypy concerns its component features, one of which being blunted or constricted affect. While several investigations have addressed this common (")negative(") symptom within the context of schizophrenia, few have focused on schizotypy directly, and none have utilized psychophysiological measurement to examine affective constriction. The present investigation uses facial electromyography (EMG)...
Show moreSchizotypy is a sub-threshold syndrome associated with schizophrenia. Much of the research on schizotypy concerns its component features, one of which being blunted or constricted affect. While several investigations have addressed this common (")negative(") symptom within the context of schizophrenia, few have focused on schizotypy directly, and none have utilized psychophysiological measurement to examine affective constriction. The present investigation uses facial electromyography (EMG) to measure patterns of affective expression within a psychometrically defined schizotypal population when presented threatening and distressing pictures from the IAPS. Twenty-eight individuals with elevated schizotypal features and 20 healthy controls were recruited for this investigation. The participants observed the series of pictures and provided self-report ratings of affective valance and arousal while their physiological responses were recorded. The protocol used here closely matched that used by Bradley and Lang (2007) and produced a similar pattern of results across all participants on self-reported ratings and physiological measures. Results further suggest that those with schizotypal features did not differ from control participants in self-reported ratings of negative affect or autonomic arousal. A three-way interaction in facial EMG measurement revealed that while schizotypic males demonstrated the expected pattern of blunted facial affective expression, schizotypic females displayed the opposite pattern. That is, females with psychometrically schizotypy demonstrated significant elevations in negative facial affective expression while viewing distressing pictures. We argue that these findings reflect unidentified sex differences in affective expression in schizotypy, and we discuss implications for assessment and diagnostic procedures among individuals with personality disorders.
Show less - Date Issued
- 2013
- Identifier
- CFE0004721, ucf:49808
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004721
- Title
- The Cross Education of Neuromuscular Economy.
- Creator
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Beyer, Kyle, Fukuda, David, Hoffman, Jay, Stout, Jeffrey, Fragala, Maren, University of Central Florida
- Abstract / Description
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Cross education is the phenomenon by which the untrained limb will experience a gain in strength following a unilateral resistance training program. However, little is known as to the underlying adaptation occurring in the untrained limb. Purpose: To examine the effect of dynamic unilateral resistance training on the strength and neuromuscular adaptations of both the trained and untrained legs. Methods: Eight previously untrained males (22.38(&)#177;2.92 y, 1.73(&)#177;0.08 m, 75.26(&)#177;14...
Show moreCross education is the phenomenon by which the untrained limb will experience a gain in strength following a unilateral resistance training program. However, little is known as to the underlying adaptation occurring in the untrained limb. Purpose: To examine the effect of dynamic unilateral resistance training on the strength and neuromuscular adaptations of both the trained and untrained legs. Methods: Eight previously untrained males (22.38(&)#177;2.92 y, 1.73(&)#177;0.08 m, 75.26(&)#177;14.53 kg) completed a four-week unilateral resistance training program, while another eight untrained males (24.00(&)#177;4.57 y, 1.84(&)#177;0.05 m, 94.21(&)#177;16.14 kg) served as controls. Isometric leg extension strength, leg press 1 repetition maximum (1RM), leg extension 1RM, root mean square of the maximal electromyographic amplitude (EMG), submaximal EMG, dynamic neuromuscular economy (NME) and the slope of NME-power output relationship were determined before and after training to assess the changes in strength and neuromuscular adaptations of the vastus lateralis (VL) and rectus femoris (RF) in both the trained and untrained legs. The unilateral resistance training program was conducted on the dominant leg (DOM) in the unilateral resistance training group (URT) and was compared to the dominant leg of the control group (CON). Cross education was measured in the nondominant leg (NON) for both groups. The unilateral resistance training program was completed three days per week for a total of twelve training sessions. Exercises included in the training program were unilateral leg press, unilateral leg extension, bilateral chest press and bilateral low row. All data was analyzed using one-way analysis of covariance of the post-testing values using the pre-testing values as the covariate. Further analysis of the EMG and NME data was performed using magnitude-based inferences. Results: The URT group improved their isometric (DOM:11.03%, NON:4.98%), leg press (DOM:77.63%, NON:64.88%) and leg extension (DOM:46.76%, NON:16.43%) strength after the four weeks of resistance training. There was no difference between the groups in isometric strength in the dominant (p=0.188) or nondominant (p=0.948) leg. For leg extension 1RM, there was a significant difference between groups in the dominant leg (p=0.018), but not the nondominant leg (p=0.482). However, there were significant group differences in both the dominant (p=0.003) and nondominant (p=0.034) leg for leg press 1RM. In terms of maximal EMG, the training groups improved in the vastus lateralis (DOM:29.81%, NON:31.44%) and rectus femoris (DOM:20.71%, NON:6.26%) individually, as well as in total EMG (DOM:24.78%, NON:17.57%). There was a Likely Positive or Very Likely Positive effect of unilateral resistance training on the changes in maximal EMG of the vastus lateralis and rectus femoris in both the dominant and nondominant legs. There was a Likely Positive effect of unilateral resistance training on the submaximal EMG of the dominant vastus lateralis at 75 and 125 watts. Conversely, in the rectus femoris, there was Unclear effects of unilateral resistance training on the submaximal EMG of the dominant leg. There was no consistent effect of unilateral resistance training on submaximal EMG values of the vastus lateralis in the nondominant leg. However, the rectus femoris in the nondominant leg experienced a Likely Positive effect of unilateral resistance training on submaximal EMG. NME improved in the URT group in the VL at 75 (DOM:9.73%, NON:13.42%), 100 (DOM:8.76%, NON:8.21%), and 125(DOM:24.26%, NON:12.8%) watts and in the RF at 75 (DOM:22.25%, NON:15.73%), 100(DOM:24.85%, NON:17.05%) and 125 (DOM:30.99%) watts. In terms of neuromuscular economy, there was a Likely Positive or Very Likely Positive effect of unilateral resistance training on most measures of NME on both the vastus lateralis and rectus femoris in both the dominant and nondominant legs. In terms of NME slope, there was only a Likely Positive effect of unilateral resistance training on the dominant vastus lateralis. Conclusion: Based on these results, it appears that the cross education of strength from unilateral resistance training is modality-specific. Furthermore, the NME of both the vastus lateralis and rectus femoris in both legs appear to improve following unilateral resistance training. However, in the nondominant leg, the improvement in NME appears to be due solely to the increase in maximal EMG, whereas the improved NME in the dominant leg is due to both an increase in maximal EMG and a decrease in submaximal EMG.
Show less - Date Issued
- 2014
- Identifier
- CFE0005305, ucf:50537
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005305
- Title
- Effect of Acute L-Alanyl-L-Glutamine (Sustamine) and Electrolyte Ingestion on Plasma Electrolytes, Physiologic Measures, and Neuromuscular Fatigue during Endurance Exercise.
- Creator
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McCormack, William, Hoffman, Jay, Stout, Jeffrey, Fragala, Maren, Virgets, Thomas, University of Central Florida
- Abstract / Description
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The purpose of this study was to compare the efficacy of two dose levels of L-Alanyl-L-Glutamine in a commercially available sports drink to the sports drink only on time to exhaustion,neuromuscular fatigue and physiological measures during prolonged endurance exercise. Twelve endurance-trained males (23.5(&)#177;3.7 yrs; 175.5(&)#177;5.4 cm; 70.7(&)#177;7.6 kg) performed four trials, each consisting of 1 hr treadmill runs at 75% of VO2peak followed by a run to exhaustion at 90% of VO2peak....
Show moreThe purpose of this study was to compare the efficacy of two dose levels of L-Alanyl-L-Glutamine in a commercially available sports drink to the sports drink only on time to exhaustion,neuromuscular fatigue and physiological measures during prolonged endurance exercise. Twelve endurance-trained males (23.5(&)#177;3.7 yrs; 175.5(&)#177;5.4 cm; 70.7(&)#177;7.6 kg) performed four trials, each consisting of 1 hr treadmill runs at 75% of VO2peak followed by a run to exhaustion at 90% of VO2peak. The trials differed in type of hydration. One trial consisted of no hydration (NHY),another required ingestion of only a sports drink (ET), and two trials required ingestion of a low dose (LD) (300 mg?500 ml-1) and high dose (HD) of L-Alanyl-L-Glutamine (1 g?500 ml-1) mixedin the sports drink. During the fluid ingestion trials 250 ml were consumed every 15 min. Plasmaglutamine, glucose, electrolytes, and osmolality were measured prior to the run (PRE), and at 30, 45, and 60 min. VO2, RQ, and HR were measured every 15 min and surface electromyography (EMG) of the vastus lateralis and rectus femoris were measured every 10 min during the 1 hr run. Time to exhaustion was significantly longer during the LD and HD trials compared with NHY. Plasma glutamine concentrations were significantly elevated at 45 min in LD and HD trials, and remained elevated at 60 min during HD. Sodium concentrations increased with the beginning of exercise and remained stable for the duration of the 1 hr run. At 60 min plasma sodium was significantly lower in all trials compared with NHY. The results from this study indicated that ingestion of the alanine-glutamine dipeptide at either the low or high dose significantly improved time to exhaustion during high intensity exercise compared to a no hydration trial. These differences were not noted between ET and NHY.
Show less - Date Issued
- 2014
- Identifier
- CFE0005209, ucf:50649
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005209
- Title
- SUBTYPES OF ANHEDONIA AND FACIAL ELECTROMYOGRAPHYRESPONSE TO NEGATIVE AFFECTIVE PICTURES IN HEALTHY ADULTS.
- Creator
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Kadison, Lisa, Bedwell, Jeffrey, University of Central Florida
- Abstract / Description
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Flat affect (i.e., diminished expressivity) and self-reported anhedonia (i.e., lack of pleasure) are associated with many psychiatric disorders. There is a need to examine the relationship between specific anhedonia subtypes and flat affect in a non-clinical sample. Forty-seven undergraduate students (59% male; mean age 20.37; SD = 4.74) completed self-report questionnaires assessing four subtypes of anhedonia - consummatory/anticipatory by social/non-social. Participants then viewed 15...
Show moreFlat affect (i.e., diminished expressivity) and self-reported anhedonia (i.e., lack of pleasure) are associated with many psychiatric disorders. There is a need to examine the relationship between specific anhedonia subtypes and flat affect in a non-clinical sample. Forty-seven undergraduate students (59% male; mean age 20.37; SD = 4.74) completed self-report questionnaires assessing four subtypes of anhedonia - consummatory/anticipatory by social/non-social. Participants then viewed 15 randomly-presented pictures (five neutral, ten negative) from the International Affective Pictures System while facial muscle activity (electromyography; EMG) was recorded. Male participants reporting a greater level of anhedonia, particularly consummatory social anhedonia, showed greater EMG activity change in the corrugator supercilii muscle to negative pictures, as compared with neutral pictures. Females showed the opposite pattern: more consummatory social anhedonia related to less EMG activity change in the corrugator muscle. In summary, consummatory social anhedonia in particular showed a strong relationship with facial expressivity that interacted with sex. In the presence of more consummatory social anhedonia, males show more negative facial reactions to negative stimuli while females show a more flattened affect. These findings may help explain discrepancies in existing research examining anhedonia and flat affect in clinical populations and have implications for etiology and treatments.
Show less - Date Issued
- 2013
- Identifier
- CFH0004377, ucf:44993
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004377
- Title
- The Reproducibility and Validity of Using the Dmax Method to Predict Physical Working Capacity at Fatigue Threshold.
- Creator
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Riffe, Joshua, Stout, Jeffrey, Hoffman, Jay, Fukuda, David, University of Central Florida
- Abstract / Description
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Although the original (ORG) physical working capacity at fatigue threshold (PWCFT) assessment has demonstrated strong reliability and sensitivity to training and/or nutritional interventions, limitations may exist regarding the method of PWCFT estimation. However, a relatively new mathematical method, called Dmax, has been shown to be objective and reliable when estimating metabolic and neuromuscular fatigue thresholds. To date, however, no study has examined whether the Dmax method for...
Show moreAlthough the original (ORG) physical working capacity at fatigue threshold (PWCFT) assessment has demonstrated strong reliability and sensitivity to training and/or nutritional interventions, limitations may exist regarding the method of PWCFT estimation. However, a relatively new mathematical method, called Dmax, has been shown to be objective and reliable when estimating metabolic and neuromuscular fatigue thresholds. To date, however, no study has examined whether the Dmax method for estimating the work rate at PWCFT is similar to the ORG method. PURPOSE: The purpose of this study is to evaluate the reliability and validity of the Dmax-EMG method for estimating and tracking changes in PWCFT. METHODS: In the reproducibility study, 11 men (age: 21.9 (&)#177; 1.37 years; height: 175.6 (&)#177; 8.65 cm; body mass: 82.1 (&)#177; 13.92 kg) completed two incremental exercise tests (GXT) to exhaustion on nonconsecutive days. In the validity study, 11 active men (age: 23.4 (&)#177; 3.0 years; height: 177.9 (&)#177; 7.8 cm; body mass: 80.9 (&)#177; 10.7 kg) and 10 active women (age: 22.3 (&)#177; 3.1 years; height: 166.6 (&)#177; 9.5 cm; body mass: 62.8 (&)#177; 8.7 kg) volunteered to perform 12 sessions of high-intensity interval training (HIIT) over 4-weeks along with a pre- and post-training GXT to compare the Dmax to the ORG method of estimating PWCFT. RESULTS: The reproducibility study revealed no significant differences between the first (181.5 (&)#177; 29.2 W) and second (181.9 (&)#177; 26.18 W) GXT trials (p = 0.87). In addition, ICC3,1 resulted in 0.949 with an SEM of 6.28 W and a MD of 17.41 W. In the cross-validation, the CE between actual and predicted PWCFT was not statistically different at pre (-6.7 W; p (>) 0.05) or post (-7.2 W; p (>) 0.05). Pre (r = 0.87) and post (r = 0.84) validity coefficients were considered very strong and the pre and post TE PWCFT values were 30.8 W and 32.5 W, respectively. Wide limits of agreement were calculated in the Bland-Altman analyses (pre: -68.36 to 54.93 W; post: -57.77 to 72.06 W) with no significant biases in both pre (-6.7 (&)#177; 30.8 W; p = 0.330) and post (-7.2 (&)#177; 32.5 W; p = 0.325). In addition, 95.2% and 100% participants fell within (&)#177;1.96 standard deviations of the mean difference for pre and post, respectively. CONCLUSION: Results of the study suggest that the Dmax method is both a reproducible and a valid method to estimate PWCFT when compared to the ORG method in young men.
Show less - Date Issued
- 2016
- Identifier
- CFE0006168, ucf:51155
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006168
- Title
- The Effects of Sprint Interval Training and Maturity Status on Metabolic and Neuromuscular Fatigue Thresholds in Adolescents.
- Creator
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Beyer, Kyle, Fukuda, David, Hoffman, Jay, Stout, Jeffrey, Fragala, Maren, University of Central Florida
- Abstract / Description
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Purpose: To examine the maturity-related differences in the adaptations to systemic and localized fatigue thresholds (FTs) in response to sprint interval training (SIT) amongst adolescent male athletes. Methods: Twenty-seven adolescent male athletes, 11-17 years of age, completed pre-testing, six weeks of SIT, and post-testing. Participants were grouped according to their number of years from peak height velocity (PHV), an estimation of somatic maturity status, into PRE (()+1.5yr) PHV groups....
Show morePurpose: To examine the maturity-related differences in the adaptations to systemic and localized fatigue thresholds (FTs) in response to sprint interval training (SIT) amongst adolescent male athletes. Methods: Twenty-seven adolescent male athletes, 11-17 years of age, completed pre-testing, six weeks of SIT, and post-testing. Participants were grouped according to their number of years from peak height velocity (PHV), an estimation of somatic maturity status, into PRE ((<)-1.5yr), PERI (between -1.5 to +1.5yr) and POST ((>)+1.5yr) PHV groups. Each testing session consisted of a ramp exercise protocol on a cycle ergometer. During the protocol, three systemic FTs, gas exchange threshold, ventilatory threshold, and respiratory compensation point were calculated from gas exchange and ventilatory parameters. Also, three localized FTs, neuromuscular fatigue threshold (NFT), deoxyhemoglobin breakpoint (HHbBP), and oxygenation deflection point (OxDP) were calculated from electromyography (NFT) and near-infrared spectroscopy signals (HHbBP and OxDP) from the vastus lateralis of both legs. Data were plotted versus oxygen consumption and 30-second moving averages were calculated. All FTs were determined using the maximal distance method. Localized FTs were averaged between the two legs. The six weeks of SIT consisted of repeated 20-second (")all-out(") sprints on a cycle ergometer against a load equivalent to 7.5% of body mass with 4-minute rest periods. Maturity-related differences to the adaptations to SIT were assessed with mixed-factorial ANOVA and magnitude-based inferences. Results: During training, POST and PERI completed significantly greater relative work (p=0.003 and p=0.002, respectfully) and peak power (p=0.025 and p=0.023, respectfully) per session than PRE. Furthermore, POST achieved significantly greater peak rotations per minute than PRE (p=0.001) and PERI (p=0.042) during the first training session. No significant group(&)#215;time interactions existed for absolute V?O2max (p=0.386), relative V?O2max (p=0.341) or maximum workload (p=0.593). However, there was a significant group(&)#215;time interaction (p=0.030) for FTs, with POST having significantly greater changes than PRE (p=0.026) and PERI (p=0.023), and was the only group to experience a significant improvement in FTs from training (p(<)0.001). In addition, magnitude based inferences revealed that POST had Likely improvements in all measures of maximal aerobic performance, while PERI only had Likely improvements in maximum workload and PRE experienced Trivial changes. Furthermore, all measured FTs experienced Likely or Very Likely improvements amongst POST; however, PRE and PERI only had improvements in NFT and HHbBP. Conclusion: SIT improved maximal aerobic performance and FTs in POST, but had limited affects in PRE and PERI. The maturity-related differences in the adaptations to SIT may be due to the differences in performance during the training program or underlying physiological changes that occur with maturation.
Show less - Date Issued
- 2017
- Identifier
- CFE0006934, ucf:51644
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006934
- Title
- Affective and Autonomic Responses to Erotic Images among Young Women with and without Sexual Difficulties.
- Creator
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De Pesa, Natasha, Cassisi, Jeffrey, Negy, Charles, Joseph, Dana, University of Central Florida
- Abstract / Description
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Existing models of female sexual dysfunction (FSD) are broad and do not provide information about how to improve existing interventions. The purpose of the current study is to extend the empirical application of a disgust model of FSD (de Jong, van Overveld, (&) Borg, 2013) to a population of young women reporting difficulties with sexual desire and/or arousal and related distress. Sixty college-aged females participated in the study and were placed into two groups based upon their reports of...
Show moreExisting models of female sexual dysfunction (FSD) are broad and do not provide information about how to improve existing interventions. The purpose of the current study is to extend the empirical application of a disgust model of FSD (de Jong, van Overveld, (&) Borg, 2013) to a population of young women reporting difficulties with sexual desire and/or arousal and related distress. Sixty college-aged females participated in the study and were placed into two groups based upon their reports of sexual functioning and sexual distress: a control group (i.e., no sexual difficulties or distress) and a clinical group (i.e., difficulties with sexual desire and/or arousal and accompanying distress). Participants were attached to physiological equipment and shown images displaying neutral, positive, disgusting, and erotic content. It was hypothesized that the clinical group would show more evidence of disgust (via affective and autonomic responses) than the control group. Consistent with hypotheses, no group differences were found in any of the affective or autonomic measures during presentation of the neutral, positive, or disgust images. Group differences during presentation of the erotic images (i.e., in facial EMG, heart rate, and self-report affective ratings) and follow-up analyses provided preliminary evidence for generalizing the disgust model of female sexual dysfunction beyond disorders of sexual pain, at least among some women. Exploratory analyses implicated a relationship between a history of sexual victimization and self-report disgust ratings of erotic images. Future research should further explore these relationships in order to shed more light on how disgust-based mechanisms impact the onset and maintenance of female sexual dysfunction.
Show less - Date Issued
- 2015
- Identifier
- CFE0005601, ucf:50234
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005601
- Title
- A PSYCHOPHYSIOLOGICAL INVESTIGATION OF THE PROPOSED PARADOXICAL EFFECTS OF VALUING HAPPINESS.
- Creator
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Coles, Nicholas, Sims, Valerie, University of Central Florida
- Abstract / Description
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Several researchers in happiness studies have called for an increased sociopolitical interest in indicators of societal happiness. However, recent evidence for the proposed paradoxical effects of valuing happiness suggest that an increase in society's perceived value of happiness may exert a detrimental, inverse influence on well-being. This notion is based on previous research demonstrating that manipulating participants to value happiness causes them to experience less positive emotions,...
Show moreSeveral researchers in happiness studies have called for an increased sociopolitical interest in indicators of societal happiness. However, recent evidence for the proposed paradoxical effects of valuing happiness suggest that an increase in society's perceived value of happiness may exert a detrimental, inverse influence on well-being. This notion is based on previous research demonstrating that manipulating participants to value happiness causes them to experience less positive emotions, compared to controls, when viewing positive film clips. Following the humanistic notion that the maximization of societal happiness is an advantageous sociopolitical endeavor, the proposed paradoxical effects of valuing happiness present a psychological barrier that researchers must strive to understand and, ideally, overcome. Previous experimental research on the paradoxical effects of valuing happiness has focused on participants' emotionality as an operational definition of happiness. However, drawing from the Subjective Well-Being construct, emotionality is only one of several components of happiness. Building from this Subjective-Well Being framework, this study expands upon previous research by investigating whether a valuing happiness manipulation influences participants' emotionality while they contemplate their own happiness. To examine this, nineteen participants were divided into two groups, one which received a valuing happiness manipulation (n=9) and the others served as a control group (n=10), and instructed to contemplate their personal happiness for 45 seconds. To measure participants' emotions during this task, facial electromyography data were collected from the corrugator supercilii and the zygomaticus major facial muscles, a measure that previous research suggests is sensitive to the emotional value of thought. Results indicated that participants manipulated to value happiness did not experience significant differences in facial electromyography activation compared to controls. However, although non-significant, the correlation between facial electromyography activation and participants' rating of happiness differed substantially for participants manipulated to value happiness (average r=.41 for corrugator, average r=-.09 for zygomaticus) and controls (average r=.-.29 for corrugator, average r=.14 for zygomaticus). The counterintuitive correlations for participants led to value happiness, despite not experiencing significant difference in the emotional value of the happiness contemplation task, provide preliminary evidence that these participants utilize the information retrieved from the contemplative stage in a qualitatively different way than controls when judging their own happiness. More specifically, the correlations for participants led to value happiness trend in the opposite direction of controls, demonstrating that increases in positive emotion during happiness contemplation actually are associated with lower scores on a self-report of happiness. This study suggests that the paradoxical effects of valuing happiness does not influence the retrieval of information when contemplating ones' happiness, but may influence (in an apparently detrimental fashion) how this information is utilized when judging one's happiness. Although the between-condition differences in correlations failed to reach statistical significance (more specifically, p=.09 for corrugator), this study provides preliminary evidence for the existence of a new dynamic of the proposed paradoxical effects of valuing happiness that is novel to the happiness studies discourse. Limitations, implications, and future directions are discussed.
Show less - Date Issued
- 2015
- Identifier
- CFH0004766, ucf:45360
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004766
- Title
- THE RISKS AND BENEFITS OF RUNNING BAREFOOT OR IN MINIMALIST SHOES: A SYSTEMATIC REVIEW.
- Creator
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Perkins, Kyle, Rothschild, Carey, University of Central Florida
- Abstract / Description
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The popularity of running barefoot or in minimalist shoes has notably increased in the last decade due to claims of injury prevention, enhanced running efficiency, and improved performance when compared to running in shoes (shod). A systematic review of the literature was performed using the Downs and Black checklist to assess the methodological quality of studies proposing risks or benefits between running barefoot, shod, or in minimalist shoes. The databases Ovid MEDLINE, SPORTDiscus, and...
Show moreThe popularity of running barefoot or in minimalist shoes has notably increased in the last decade due to claims of injury prevention, enhanced running efficiency, and improved performance when compared to running in shoes (shod). A systematic review of the literature was performed using the Downs and Black checklist to assess the methodological quality of studies proposing risks or benefits between running barefoot, shod, or in minimalist shoes. The databases Ovid MEDLINE, SPORTDiscus, and CINAHL were searched using keywords or "Booleans" including: "Barefoot", "Running" and "Minimalist," exclusively. All included articles were obtained from peer reviewed journals in the English language with a link to full text and no limit for year of publication. The final selection was made based on inclusion of at least one of the following outcome variables: pain, injury rate, running economy, joint forces, running velocity, electromyography, muscle performance, or edema. Significant results were gathered from identified articles and compared using "Levels of Evidence" by Furlan et al. Twenty-three publications were identified and rated for quality assessment in September 2013. Out of 27 possible points on the Downs and Black checklist, all articles scored between 13 and 19 points with a mean of 17.4. Evidence from the articles ranged from very limited to moderate. Moderate evidence suggested overall less maximum vertical ground reaction forces, less extension moment and power absorption at the knee, less foot and ankle dorsiflexion at ground contact, less ground contact time, shorter stride length, increased stride frequency (cadence), as well as increased knee flexion at ground contact in barefoot running compared to shod. The low scores from the quality assessment using the Downs and Black checklist indicates that improved methodological quality is necessary to provide strong evidence comparing the risks and benefits of running barefoot, shod, and in minimalist shoes. The literature between shod, minimalist, and barefoot running is inconclusive. There is limited evidence showing differences in kinematics, kinetics, electromyography, and economy results in minimalist shoes. Thus, an alternative and suitable method to effectively replicate barefoot running has not yet been determined.
Show less - Date Issued
- 2013
- Identifier
- CFH0004532, ucf:45194
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004532
- Title
- The effects of four weeks of high intensity interval training and (&)#223;-hydroxy-(&)#223;-methylbutyric free acid on the onset of neuromuscular fatigue.
- Creator
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Miramonti, Amelia, Stout, Jeffrey, Hoffman, Jay, Fukuda, David, University of Central Florida
- Abstract / Description
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This study investigated the effects of high intensity interval training (HIIT) and ?-hydroxy-?-methylbutyric free acid (HMBFA) on the onset of neuromuscular fatigue in healthy young men and women. Thirty-seven subjects (22 men and 15 women; mean (&)#177; SD age = 22.8 (&)#177; 3.4yrs) completed an incremental cycle ergometer test (GXT) to exhaustion. During the GXT, electromyography (EMG) signals from the right vastus lateralis were recorded to determine the power output at the onset of...
Show moreThis study investigated the effects of high intensity interval training (HIIT) and ?-hydroxy-?-methylbutyric free acid (HMBFA) on the onset of neuromuscular fatigue in healthy young men and women. Thirty-seven subjects (22 men and 15 women; mean (&)#177; SD age = 22.8 (&)#177; 3.4yrs) completed an incremental cycle ergometer test (GXT) to exhaustion. During the GXT, electromyography (EMG) signals from the right vastus lateralis were recorded to determine the power output at the onset of neuromuscular fatigue (PWCFT), and peak wattage was used to assign individual training loads.After baseline testing (PRE), subjects were randomly assigned to one of three groups: control (C, n = 9), training with placebo (P, n = 14), or training with supplementation (S, n = 14). Subjects assigned to P and S completed 12 HIIT sessions over 4 weeks while subjects assigned to C were asked to maintain their normal diet and activity patterns. After 4 weeks, subjects returned for post-testing (POST). The PWCFT values (W) were determined using a DMAX method. The EMG amplitude root mean square ((&)#181;Vrms) values were used to generate a third-order polynomial regression (3PR) representing the increase in (&)#181;Vrms versus time of the GXT. The onset of fatigue (TF) was defined as the x-value (time, s) of the point on the 3PR that measured the maximal perpendicular distance from the line between the first and last data points. TF was used to estimate PWCFT according to the equation: PWCFT = PO + a ? (n/N), where PO is the power output of the stage in which TF occurred, a is the increment in power output between GXT stages (25W), n is the difference (s) between TF and the beginning of the stage during which TF occurred, and N is the duration of a stage (120s).A two-way repeated measures ANOVA was used to identify group (&)#215; time interaction for PWCFT. If a significant interaction occurred, one-way factorial ANOVAs were used. Fisher's least significant difference post hoc comparisons were performed between groups. If a significant main effect occurred, dependent samples t-tests with Bonferroni corrections (p = [0.05/3] = 0.017) were performed across time for each group.The two-way ANOVA resulted in a significant interaction (F = 6.69, p = 0.004). Follow-up analysis with one-way ANOVA resulted in no difference among groups at PRE (F = 0.87, p = 0.43), however a significant difference was shown for POST values (F = 5.46, p = 0.009). Post-hoc analysis among POST values showed significant differences between S and both P (p = 0.034) and C (p = 0.003). No differences (p = 0.226) were noted between P and C. Paired samples t-tests detected significant changes following HIIT for S (p (<) 0.001) and P (p = 0.016), but no change in C (p = 0.473).Results of this study indicate that HIIT was effective in delaying the onset of fatigue, but supplementation with HMBFA in conjunction with HIIT was more effective than HIIT alone. An increase in PWCFT represents an increase in the maximal power output an individual can sustain without eliciting fatigue. Therefore, HIIT can be used to improve performance in both endurance activities as well as intermittent sports. In addition, HMBFA supplementation is a simple method that can be used to maximize the benefits of HIIT.Acknowledgments: Metabolic Technologies, Inc. provided the supplement and funding for this study.
Show less - Date Issued
- 2015
- Identifier
- CFE0006043, ucf:50968
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006043
