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The Effects of Whole Body Vibration on Strength Gains in the Bench Press, the Back Squat, and the Power Clean in Division I Football PlayersPoppinga, Kelly S. 06 December 2010 (has links) (PDF)
The purpose of this study was to determine if whole body vibration effects strength gains in the bench press, the back squat, and the power clean in division 1 football players. Thirty-one NCAA Division 1 male football players volunteered for this study and were randomly assigned to a control group (C=16) or one of two vibration groups (V1=7, V2=8). Subjects followed the training program for eight weeks. A pre-test, mid-test, and post-test one repetition max was measured at 0, 4, and 8 weeks for the bench press, the back squat, and the power clean. A 3x3 factorial ANOVA revealed varied results between the three lifts performed. In the bench press, there were no significant differences in strength gains between the three training groups (F=.616, p=.547). In addition, there was no significant interaction (F=1.05, p=3.74). There were significant differences between trials in the bench press in strength gains (F=7.570, p=.006). In the back squat, there were no significant differences in strength gains between the three training groups (F=.847, p=.440). In addition, there were no significant differences in interaction (F=1.734, p=1.83). There were significant differences between trials in the back squat in strength gains (F=17.111, p<.001). In the power clean, there were no significant differences in strength gains between the three training groups (F=.666, p=.522). In addition, there were no significant differences in interaction (F=.113, p=.912). There were significant differences between trials in the power clean in strength gains (F2=26.249, p<.001). While all groups registered significant strength gains over trials, there were no significant differences in strength gains between any of the three treatment groups or any of the three dependant variables. It was concluded that whole body vibration does not enhance strength gains in division I football players.
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The Effects of the ReBound Diathermy Unit, Megapulse II Shortwave Diathermy Unit and Moist Hot Packs on Tissue Temperature Increase of the Triceps Surae Muscle GroupHawkes, Amanda Rose 16 June 2011 (has links) (PDF)
Context: Clinicians use a number of superficial and deep heating modalities, including pulsed shortwave diathermy (PSWD) and moist hot packs, in the clinical setting. Recently, a continuous diathermy unit called ReBound was introduced into the clinical setting. Its effectiveness as a heating modality is unknown. Objective: To compare the effects of PSWD, moist hot packs and the ReBound unit on tissue temperature in the triceps surae muscle. Design: A 3 x 27 factorial cross-over design with repeated measures. Setting: University research laboratory. Subjects: Twelve healthy college-aged volunteers (4 men, 8 women; age = 22.2 ± 2.25; calf subcutaneous fat thickness = .72 cm ± .19 cm). Interventions: On three different days separated by at least 48 hours, one of three modality treatments (PSWD, moist hot packs or ReBound unit) selected using a Latin-square was applied to the triceps surae muscle of each participant for 30 minutes. After the 30 minute treatment, the modality was removed and temperature decay was recorded for 20 minutes. Main Outcome Measures: Medial triceps surae intramuscular tissue temperature at 1 cm and 3 cm deep was measured using implantable thermocouples inserted horizontally into the muscle. Measurements were taken every 5 minutes during the 30 minute treatment and every minute during the 20 minute temperature decay for a total of 50 minutes. A 3 x 27 mixed model analysis of variance blocking by subject was used to assess the effects of treatments and time, and their interaction on the tissue temperature at 1 cm and 3 cm depths. Results: A significant treatment by time interaction main effect was found for tissue temperature increase at each depth, 1 cm (F52, 572 =14.66, p < .0001) and 3 cm (F52, 572 = 17.86, p < .0001). Post-hoc measures revealed that tissue temperature significantly increased with the PSWD over the ReBound unit and moist hot packs at 1 cm and 3 cm depths. There was no significant difference between the ReBound unit and moist hot packs throughout the treatment and temperature decay. The greatest mean tissue temperature increase from baseline was observed with the PSWD unit at 1 cm (5.96°C ± 2.04°C) and at 3 cm (4.32°C ± 1.79°C). There was no statistical difference between the increases observed with the ReBound (1 cm: 3.69°C ± 1.50; 3 cm: 2.31°C ± .87) and moist hot packs (1 cm: 2.82°C ± .90; 3 cm: 1.56°C ± 1.00). Conclusions: During a 30 minute treatment, PSWD was the most effective at increasing intramuscular tissue temperature of the triceps surae muscle group. There was no significant difference between the effectiveness of moist hot packs and the ReBound continuous diathermy unit in increasing intramuscular tissue temperature.
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Electromyographic Analysis of the Infraspinatus and Deltoid Muscles During Shoulder External Rotation Exercises With and Without a Towel RollSakita, Kazuto 15 November 2010 (has links) (PDF)
Standing and sidelying external rotation exercises produce high activation of the deltoid and infraspinatus. Holding a towel roll under the arm at 30° shoulder abduction during these exercises may decrease deltoid activity and increase infraspinatus activity. The objective was to determine if the addition of a towel under the arm during standing and sidelying external rotation affects EMG activity of the infraspinatus, middle and posterior deltoid, and pectoralis major, compared to the no towel condition. 20 male volunteers (age; 26 ± 3, height; 1.80 m ± .07 m, weight; 77 kg ± 10 kg) had right dominant hand, bilaterally healthy shoulders with no current cervical pathology, and no skin infection or lesion of the shoulder. Maximal voluntary isometric contraction for the infraspinatus, middle and posterior deltoid, and pectoralis major and external rotation in standing and sidelying with and without a towel roll were performed. Normalized average and peak EMG amplitude was compared between the towel conditions during standing and sidelying external rotation. Both infraspinatus and pectoralis major activity had no significant differences between the towel conditions in standing and sidelying (P > .05). In standing and sidelying, posterior deltoid activity was significantly greater with a towel roll (.008 ≤ P ≤ .035 and .008 ≤ P ≤ .018, respectively). Middle deltoid activity had no significant differences between the towel conditions in standing (P > .05). However, in sidelying, middle deltoid activity was significantly lower with a towel roll (.011 ≤ P ≤ .000). The only muscle activation change during standing external rotation with the application of a towel roll was an increase of the posterior deltoid. During sidelying external rotation, holding a towel roll decreased middle deltoid activity and increased posterior deltoid activity. Thus, this study indicates that holding a towel roll under the arm during standing external rotation exercise does not appear to produce desired effects on muscle activation. However, application of a towel roll under the arm could be recommended during sidelying external rotation exercise in order to possibly reduce the superior glide of the humerus, due to decrease muscle activation of the middle deltoid.
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Comparison Between the Trap Bar Dead Lift and Back Squat Exercises on Vertical JumpYoung, Douglas A. 13 July 2011 (has links) (PDF)
The ability to produce power during competition is essential. Football requires explosive power in order to get off the ball faster, increase speed of the first step, and increase the height of the vertical jump. Most strength training professionals use the back squat to increase power of the lower extremities; however, as large forces are placed on the back, athletes are at greater risk for injury. The trap bar dead lift is similar to the back squat in movement and form, but the trap bar dead lift reduces the force on the lower back. After testing for maximum vertical jump,athletes at Timpview High School participated in a strength program using either back squats or trap bar dead lift for seven weeks. A pre-test, mid-test and post-test were performed to calculate the increase in maximum vertical jump, if any. It was found that neither lift was significantly different than the other when testing for maximum vertical jump. These results will allow strength training professionals to use the trap bar dead lift instead of the back squats in subjects similar to those participating in the study.
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The Effect of an Acute Bout of Exercise on Food Motivation, Energy Intake, and Total Physical Activity in Normal-Weight and Obese Woman: An Event-Related Potential StudyHanlon, Nonie Erin Bliss 10 November 2011 (has links) (PDF)
This study examined the effect of acute exercise on food motivation, energy intake, and total physical activity in normal-weight and obese women. Participants of both groups were matched (except for Body Mass Index) and conditions (exercise vs. non-exercise) were randomized and counter-balanced. Eighteen normal-weight and 17 obese women completed an exercise and non-exercise day, each performed on the same day of the week. Exercise was performed on a motor-driven treadmill at 3.8 mph and 0% grade for 45 continuous minutes. To test for food motivation, participants were shown a continuous stream of pictures of food and flowers (control) while neural activity was monitored. Data were analyzed using a 2-group x 2-exercise condition x 2-picture type repeated measures analysis of covariance on event-related potential (ERP) amplitude and latency. Dietary records were analyzed using the Food Processor SQL nutrition software. Physical activity was monitored using a GT1M accelerometer. For both groups under both conditions, ERP amplitude was higher and latency was lower for food pictures compared to flower pictures. When normal-weight and obese women were combined, there was a significant condition*picture type interaction for late positive potential (P=0.04) with participants showing less neurological response to food pictures following a 45-minute exercise bout. Exercise did not alter energy intake. However, the exercise condition resulted in significantly more total physical activity, moderate intensity, vigorous intensity, moderate-to-vigorous (MVPA) intensity activity, and less sedentary time than the non-exercise condition. There was a significant group*condition interaction for MVPA (P=0.043) with obese women showing less MVPA than the normal-weight group. The sample of women studied did not show neurological differences in response to pictures of food based upon BMI. However, exercise decreased neurological responses to food, which may indicate lower food motivation. A supervised and planned exercise bout dramatically increased total physical activity in normal-weight and obese women compared to a day without planned exercise. There may be some negative compensation for MVPA in obese women following a 45-minute exercise bout compared to normal-weight women.
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The Effects of Whole Body Vibration on Dorsiflexion in Chronic Ankle InstabilityThalman, Lesley Abigail 09 December 2011 (has links) (PDF)
BACKGROUND: Whole body vibration (WBV) platforms are currently used as adjunctive training devices for exercise programs, and have been shown to facilitate flexibility. One of the biggest contributing factors to chronic ankle instability (CAI) is the lack of dorsiflexion after lateral ankle sprains and WBV may be an effective way to increase range of motion in this population. PURPOSE: Determine if WBV done concurrently with static stretching (SS) is more effective then SS alone in improving dorsiflexion ROM in subjects with CAI. METHODS: Subjects were divided into 3 groups (control, static stretch, and static stretch and vibrate). Subjects stretched 4 days/wk for 3 wks for 4 sets of 30 seconds alternating 2 different positions to stretch both the soleus and the gastrocnemius. Imposed vibration at 34 Hz 2mm during the stretches for the stretch group. ANALYSIS: Repeated measures ANOVA was performed using SPSS (version 19), with post-hoc Tukey tests as needed (p<.05). RESULTS: In both the straight and bent leg position, a significant group x time interaction was found for dorsiflexion range of motion. Post hoc tests revealed significance in the SV group between pre-tx and post-tx 1 and pre-tx and post-tx 2. No statistical significance was found between post-tx 1 and post-tx 2 in the SV group or at any time in the N or SS group. DISCUSSION: Static Stretching with vibration increases dorsiflexion ROM in subjects with CAI better than static stretching alone.
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Lower Body Kinetics During the Delivery Phase of the Rotational Shot Put TechniqueWilliams, Jillian Mary 07 March 2012 (has links) (PDF)
The purpose of this study was to measure the change in joint energy of the hip,knee and ankle of the right and left leg, in the sagittal plane during the delivery phase of the rotational shot put. We hypothesized that (1) throwers who produced a greater total hip energy change would have greater horizontal displacement and (2) throwers who produced a higher ratio of hip energy, in each leg independently, would produce greater horizontal displacement. Subjects (n = 8) must have been right-handed, collegiate or post collegiate level throwers trained in the rotational technique. Vicon Nexus System (Denver, CO, USA) used six MX13+, two F20, two T20 cameras recorded at 240 Hz, and the body Plug-in Gait model to track the body position during each trial. Two AMTI force plates (OR-6, Watertown, MA, USA) were used for collecting ground reaction force data at 960 Hz. A linear regression analysis was performed to determine a relationship between total hip energy change and horizontal displacement. A mixed model regression was used to determine any correlation between horizontal distance and left and right energy change ratios. Athletes who produced a greater total hip energy change had the greatest horizontal displacement (p = .022). Also throwers who produced a higher ratio of left hip energy change to total left leg energy produced the greatest horizontal displacement (p = .02). The ratio of right hip energy change to right leg energy change was found to not be significant to horizontal displacement (p = .955). We feel the findings on the left leg energy change are an attempt by the athlete to both accelerate the shot put as well as stop the rotational progression to allow the athlete to complete a fair throw. The athlete extending both the right and the left hip rapidly during the delivery phase can help explain the combined right and left hip energy change. This action accelerates the ball in a proximal-distal sequence, which allows athletes to reach high final shot put velocities. The higher the final velocity on the shot put positively correlates with the horizontal displacement.
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Lower Extremity Joint Moments During the Active Peak Vertical Ground Reaction Force in Three Different Running ConditionsStandifird, Tyler W. 07 March 2012 (has links) (PDF)
The purpose of this study was to compare joint moments during the active peak vertical ground reaction force (PVGRF) when running in three conditions. Twenty-five subjects, sixteen male and nine female, were measured using 3-dimensional motion analysis while running barefoot, in Vibram FiveFingers® (VF®) minimalist running shoes and in traditional running shoes at a 7-minute-mile pace (3.84 m/s). Joint moment differences were calculated and compared using a mixed model analysis of variance. Results showed the VF® was effective at mimicking both the kinetic and kinematic attributes of barefoot running. The only significant difference found when comparing barefoot and VF® running was in the ankle angle (p < .005). All other variables in the lower extremity were the same for the two conditions. Though the subjects in our study had no previous experience with VF® (or barefoot) running they were able to closely mimic barefoot running upon initial running trials. Joint moments at the ankle were higher for barefoot and VF® running (p < .001) when compared with shod running. This may potentially lead to a greater risk of injury at the ankle joint when running barefoot or in VF®. The hip joint moments were only different when comparing the barefoot condition to the shod condition (p=.002), with the barefoot condition higher than shod running. The knee joint moment was smaller during the VF® and barefoot conditions when compared with shod running (p < .001) and may lead to a decrease in injury rates at the knee. Though a reduction in moments of the lower extremity may lead to a decrease of injury at the corresponding joint, it is important to consider the adaptations that take place as a result of varying stresses. According to Wolff's law, bone and surrounding tissue will adapt to the loads it is placed under. Taking this into consideration, it is important to remember that lower moments may lead to weaker bones and surrounding tissues and without compensation for these reduced loads, injury rates may remain the same over time.
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The Effect of Passive Stretching and Isometric Contractions on Delayed Onset Muscle Soreness After a Typical Bout of ExerciseGibson, John W. 15 December 2010 (has links) (PDF)
Delayed Onset Muscle Soreness (DOMS) is a common response to activities involving lengthening contractions. Muscle inflammation is associated with DOMS and may play an integral role in protecting a muscle from damage and soreness in response to subsequent bouts of lengthening contractions. Research in animals has shown that prior exposure to passive stretching and isometric contractions of a muscle resulting in muscle inflammation attenuates the muscle inflammatory response following subsequent bouts of lengthening contractions. The purpose of this study was to determine whether passive stretching and isometric contractions in humans would reduce DOMS following a typical bout of resistance exercise. METHODS: Thirty untrained male subjects were assigned to a control (C), stretching (S) or isometric (I) contraction group (n=10/group). In the week prior to the typical resistance training bout subjects in S and I were exposed to 3 separate sessions involving 5 minutes of passive stretching or maximal isometric contractions, respectively. Passive and active soreness, thigh girth, and relaxed knee angle were assessed prior to intervention and on days 1, 2, 4, and 8 following the bout of resistance exercise. RESULTS: Passive and active muscle soreness increased similarly in all groups. However, active soreness returned higher values than passive soreness at several time points following resistance exercise. Peak soreness occurred at 48h post exercise. Thigh girth and relaxed knee angle reached their highest values at 5 minutes following resistance exercise however there were no differences between the groups. CONCLUSIONS: The present study demonstrates that a typical bout of resistance exercise is sufficient to cause measurable levels of DOMS in untrained subjects and that subjects are more sensitive to active measures of DOMS compared to a passive assessment. Nevertheless the passive stretching and isometric contraction interventions did nothing to reduce DOMS in the current subjects.
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Neuromechanical Alterations Due to Induced Knee Pain and Effusion During Functional MovementsPark, Jihong 09 December 2011 (has links) (PDF)
Purpose: Examine neuromechanical alterations due to isolated and/or combined knee pain and effusion in functional movements. Methods: A 4X3 randomised controlled laboratory study with repeated measures was used. Nineteen, healthy volunteers (age: 22.4 ± 2.4 years) underwent four different treatments (control, effusion, pain, and pain/effusion) with a week wash out period. Ten near-infrared cameras with 43 reflective markers, 12 surface EMG electrodes, and two ground-embedded force platforms were used to record neuromechanical changes during functional movements (walking and drop landing). To induce pain, 5% sodium chloride (1 ml) was injected into the infrapatellar fat pad. To induce effusion, 0.9% sodium chloride (50 ml) was injected into the knee joint capsule. To induce pain/effusion, both injections were employed. No injection was used for the control. Subjects performed walking and a single leg drop landing in three time intervals: precondition (prior to injection), condition (immediate post injection), and postcondition (30 min post injection). To quantify pain perception, the visual analogue scale was measured every two minutes. Results: Under pain/effusion treatment, subjects walked slowly with a shorter stride length. Joint moments of plantarflexion, knee extension, knee abduction, and hip abduction were reduced. Subjects also showed a decrease at 20% and 80% of stance phase, and an increase in 50% in vertical ground reaction force (VGRF). Under the same treatment, subjects landed with a less peak VGRF with increased time to peak VGRF, alterations of joint angles (ankle dorsiflexion, knee extension, and hip adduction), and moments (knee extension, knee abduction, and hip abduction). Conclusions: Joint pain and effusion cause neuromechanical alterations in the lower extremity during functional movements. These compensatory strategies may alter joint loading, potentially resulting in acceleration of the joint degenerative process. We also recommend use of crutches following injury to avoid modifications of movement strategies.
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