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The purpose of this study was to investigate the kinetic and kinematic implications of cluster loading as a resistance training programming tactic. Cluster loading involves introducing rest during a set which may allow athletes to train at higher absolute intensities. Eleven trained males were recruited for this study. Subjects completed two testing sessions consisting of three sets of five back squats at 80% of their one repetition maximum. Cluster loading included 30s of inter-repetition rest. All testing was done on dualforce plates with four linear position transducers. Paired sample t-tests were used to determine differences between conditions with Cohen’s d effect sizes describing the magnitude of change between conditions. Both conditions had similar values for peak force and average force. Cluster loading had significantly higher power and velocity outputs, shorter times to peak power and velocity as well as greater maintenance of time to peak power. These results suggest cluster loading may be superior to traditional loading when maintaining power output and timepoint variables is the desired outcome of training.

Strength and tone of the pelvic floor muscles are thought to play an important role in pelvic floor disorders, and are key outcomes monitored in pelvic floor rehabilitation, yet the standard approach to measuring these outcomes is through subjective assessment using manual palpation. While intravaginal dynamometers (IVD) have been designed to measure these characteristics in research settings, most are not sufficient to withstand the rigors of clinical use. This work presents the bench validation and subsequent updated design of a new mechanical constant speed mechanism for future inclusion in an IVD. Opening speeds of the original mechanism were validated with and without external loading using video analysis. The bench validation showed that the speed of arm opening was lower than the ranges specified for clinical use and was influenced by external loading. The mechanism was updated, and the bench test was repeated. The updated mechanism was found to provide output speeds that are within the ranges required clinically and were minimally impacted by external loading. The next step of this work is to reduce the size of the mechanism and improve output speeds to allow it to be assembled into a clinical prototype IVD.

The purpose of this study was to compare effects of the front squat and back squat on vertical jump and lower body power index of division 1 male volleyball players. Eighteen NCAA Division 1 male volleyball players volunteered for this study and were assigned either to a back squat or a front squat training program group. Subjects followed the training program for 8 weeks. Counter-movement vertical jump (CMVJ) height and lower body power index were measured at 0, 4 and 8 weeks of the study. A 2x3 factorial ANOVA revealed no significant difference in CMVJ height and power index between the training groups (p = 0.921). In addition, changes in power index over 8 weeks were not significant (p = 0.931). There was significant improvement for both groups in CMVJ height from 0 to 4 weeks (p = .001) and from 0 to 8 weeks (p = .000), but not from 4 to 8 weeks (p =.080). Both front squat and back squat strength training programs were both equally effective at enhancing CMVJ performance.

Athletes of American football need the ability to stop, start, and reach top speed in an efficient manner. Football players on the defensive side of the ball require the skill of stopping a backward run and accelerating to a forward run. This action is termed the break. Football players receive year-round training in an effort to improve performance. Yet, many times, these athletes may not focus specifically on the muscular systems that are unique to the position they play. The law of specificity states that the more specific the training is for the action required, the more beneficial the outcome. This study utilized seventeen defensive players of a Division IA football team and compared the effect of two training programs on acceleration during the break. The first program was a standard conditioning program (SCP) for football players. The second program was the SCP combined with three ballistic-plyometric drills (BPD) designed to improve the acceleration of the break. The groups were pre tested and divided into either the SCP or the BPD using a matched pair ABBA procedure by position, from fastest to slowest. After six-weeks of training, the BPD group made a 24.9% (p<0.05) improvement in acceleration from 11.14 ± 0.43 m•sec2 to 13.78 ± 0.44 m•sec2. While the SCP group pre tested at 11.9 ± 0.41 m•sec2 and post tested at 12.42 ± 0.34 m•sec2 for a 6.3% change that was not statistically significant. We conclude that the addition of three specific ballistic-plyometric drills to a SCP will improve acceleration out of a break in American football players.

The purpose of this study was to compare the effects of six- and twelve-second time intervals of eccentric strength training among college males. Thirty-eight students were used in two experimental groups and one control group. Subjects in the two experimental groups trained three days a week for seven consecutive weeks and were required to perform two sets -of eccentric exercise with three repetitions in each set for either six- or twelve-second intervals, depending upon the experimental group assignment. Results indicated that there was a significant differ ence between the experimental groups' mean strength gain and that of the control group. There was no significant difference between the two experimental groups.

No description available.

OBJECTIVES: To evaluate different surface treatment effects on physical and mechanical properties of various types of zirconia subjected to hydrothermal aging. MATERIALS AND METHODS: This is an in vitro study on four different types of monolithic zirconia material: VITA-Zahnfabrik VITA-YZ T, VITA-YZ HT, VITA-YZ ST, VITA-YZ XT. A total of 240-disc specimens were prepared by core-drilling and sectioned with a diamond blade. Specimens were sintered according to the manufacturer’s recommendations. Half of the specimens in each group were then glazed and subjected to low temperature degradation. Three different locations were evaluated for surface roughness each group of the four different materials by using Mitutoyo SJ-201 contact profilometer with a 5μm diamond stylus tip. A Bruker D2 Phaser diffractometer was used for X-ray diffraction (XRD) measurements. Crystallographic phase identification and analysis were performed through Rietveld refinements on XRD raw data. Biaxial flexural strength was determined and the fractography was analyzed. Descriptive data such as surface roughness, crystallographic phase contents, and flexural strength were indicated as mean and standard deviation (SD). Statistical analysis was performed using multi-way ANOVA and linear regression model followed by the post hoc Tukey tests. RESULTS: All VITA YZ zirconia non-glazed control specimens showed higher means of biaxial flexural strength values compared to glazed specimens. VITA YZ HT specimens showed the highest mean of biaxial flexural strength in this study with values of 781 – 1305 MPa. On the other hand, VITA YZ XT expressed the lowest mean of biaxial flexural strength values of 466 – 972 MPa. The surface roughness of monolithic VITA YZ materials was statistically significantly low for the various zirconia materials. Aging of various zirconia materials showed statistically significant effect of aging on glazed specimens was not statistically significant. There was no significant difference in the tetragonal phase content of all VITA YZ materials (p > 0.05). There was significant difference in the cubic phase content of all VITA YZ materials (p < 0.05). On the other hand, aging process as well as the interaction between the material type and aging had no significant effect on the cubic phase content of YZ specimens (p > 0.05). There was significant difference in the rhombohedral phase of all VITA YZ materials as well as aging process (p < 0.05). CONCLUSIONS: Biaxial flexural strength was significantly affected by glazing, type of material, treatment protocol. Biaxial flexural strength was significantly affected by the interaction between type of material and treatment protocol, glazing and type of material. The VITA YZ ST control had the lowest surface roughness among all the groups. The difference was statistically significant. The type of material, aging, and the interaction effect between the material and aging were significantly different for XRD in non-glazed material. The VITA YZ T showed the lowest mean of yttrium oxide (Y2O3) molecular fraction. On the other hand, YZ XT showed the highest mean of Yttrium oxide (Y2O3) molecular fraction.

SPEED AND AGILITY TRAINING THE MUSTANG WAY: THE DEVELOPMENT OF AN INSTRUCTIONAL DVD FOR CAL POLY ATHLETES’ SUMMER TRAINING Gary Douglas Heron The purpose of this project was to create an instructional DVD of speed and agility training for Cal Poly student-athletes. The DVD is for athletes’ use when they are away from campus during summer break and contains information about the same drills and information the strength and conditioning coaches provided while athletes were on campus. The project was filmed and edited by the graduate assistant strength and conditioning coach for Cal Poly intercollegiate athletics. The DVD contains 74 drills that encompass speed techniques, acceleration techniques, plyometrics, footwork, and change of direction. Recommendations for further empirical research in the area of speed and agility training are provided.

BACKGROUND: Exercise is an established treatment to alleviate pain and improve function among adults with knee osteoarthritis (KOA). However, long-term adherence to exercise is poor and effective approaches to support adherence are limited. The objective of this dissertation was to 'gain a new look' into long-term exercise adherence. With study #1, the experiences of participants in the Boston Overcoming Osteoarthritis through Strength Training (BOOST) study, were explored to identify participants' experiences, feelings and perspectives with exercise over 2-years and factors that influenced adherence to a prescribed exercise program after 2 years. With study #2, we examined if kinesiophobia: i) was associated with physical performance measures, ii) improved after a 6-week exercise program and iii) change was associated with change in pain and function among adults with KOA. METHODS: Participants of both studies completed a 6-week exercise program. For study #1 all participants received an automated telephone reminder to continue with their exercises and complete their logs, in addition, those randomized into the intervention group received a motivational computer adaptive telephone program. Participants were purposively sampled and in-depth interviews were conducted at the 2-year assessment. For study #2, data analysis was conducted prior to randomization with a sample of participants who completed the Tampa Scale of Kinesiophobia (TSK) questionnaire. Additional data included stair negotiation, 5 and 10 time sit-to-stand, and timed-up-and go tests. RESULTS: Study #1: Three themes were identified describing beliefs about exercise: i) monitoring, ii) knowledge of how to manage exercise behaviors, and iii) benefits of exercise. Those who reported high-adherence exhibited self-determination and self-efficacy, those who reported low-adherence expressed ambivalence about the benefits of exercise and a desire for more social support. Participants valued monitoring by peers and instructors during the exercise class and telephone technology. Study #2: Higher TSK was associated with slower stair and 5 time sit-to-stand times. TSK decreased after the exercise class but did not attain statistical significance. Change in TSK was associated with change in self-report physical function. CONCLUSIONS: Future research on the use of telephone technology and importance of self-determination and kinesiophobia on exercise adherence among adults with KOA is warranted.