The purpose of this study was to determine if isokinetic testing could be used as an effective means of assessing a players potential to play a certain position. The subjects were twenty four male division IA college football players. The Cybex 340 isokinetic testing device, twenty and forty yard dash, and standing broad jump were used to collect data. An analysis of variance test with repeated measures was used for the statistical analysis (ANOVA). Based on the findings of this study, no significant difference was found between offensive and defensive lineman, through isokinetic testing. However, a significant difference was found between the groups in the twenty and forty yard dash, and in the standing broad jump. Significant differences in these areas may have been attributed to a significant difference in body weight between the two groups tested. / School of Physical Education

Various body positions have been used in the scientific literature when performing the isometric midthigh pull resulting in divergent results. We evaluated force production in the isometric midthigh pull in bent (125° knee and 125° hip angles) and upright (125° knee, 145° hip angle) positions in subjects with (>6 months) and without (<6 months) substantial experience using weightlifting derivatives. A mixed-design ANOVA was used to evaluate the effect of pull position and weightlifting experience on peak force, force at 50, 90, 200, and 250 ms. There were statistically significant main effects for weightlifting experience and pull position for all variables tested, and statistically significant interaction effects for peak force, allometrically scaled peak force, force at 200 ms, and force at 250 ms. Calculated effect sizes were small to large for all variables in subjects with weightlifting experience, and were small to moderate between positions for all variables in subjects without weightlifting experience. A central finding of the study is that the upright body position (125° knee and 145° hip) should be used given that forces generated are highest in that position. Actual joint angles during maximum effort pulling should be measured to ensure body position is close to the position intended.

The purpose of this study was to compare the muscular strength and endurance of thirty-two men 51 to 79 years of age who engage in weight training (WT), aerobic training (AT), cross training (CT), or no training (S). The design employed in the study was a 2x2 between subjects factorial design with weight training and aerobic training as the two factors. A KIN/COM isokinetic dynomometer was used to test muscular strength and endurance of the dominant leg extensors and chest/shoulder complex. Strength of the leg extensors and chest/shoulder complex were measured as peak torque and peak force, respectively, at a velocity of 60 degrees/second. Endurance of the same muscle groups was measured as the percent decline over 50 continuous maximal contractions at a velocity of 180 degrees/second. A two-way between subjects ANOVA and independent t-tests were used to analyze the difference between mean muscular strength and mean muscular endurance for each group. A significant weight training effect was found for leg strength, with the WT and CT groups (Weight Trained groups) exhibiting a greater peak torque than the AT and S groups (Non-Weight Trained groups). Participating in one of three training programs was found to have a significant effect for chest and shoulder strength, with the WT, CT, and AT groups exhibiting a greater peak force than the S group. However, no significant difference was found between the WT, CT, and AT groups for chest/shoulder strength. The WT group was found to have significantly greater muscular endurance of the leg compared to the S group. No other training effects were observed between any of the groups for either muscular endurance test. / Graduation date: 1992

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

Introduction The physiological effects of single and multiday road running races have been studied extensively and include the occurrence of rhabdomyolysis, reflected by significantly increased urinary myoglobin (uMb), as well as increased concentrations of serum creatine phosphokinase (CPK), high sensitivity C-reactive protein (hsCRP), cortisol and cardiac troponin-T (cTnT), dehydration and compromised renal function. Furthermore, in hyperthermic athletes, a positive relationship has been noted between hyperthermia, muscle damage, dehydration and pacing. The physiological effects of a multiday trail run of similar duration to single day road races, however, are unknown. The side-effects of the use of statin medication for hypercholesterolaemia include muscle fatigue, cramping and increased muscle damage. These have been found to be aggravated in endurance athletes and it has been reported that females, especially when being medicated from a young age, are more susceptible to these side-effects. Objectives 1. To investigate the effect of a three-day trail run on systemic and urinary markers of muscle damage and inflammation in recreational runners and to establish the association of dehydration and hyperthermia with these markers. 2. To observe the effect of the three day trail run on systemic and urinary markers of muscle damage and inflammation on an additional hypercholesterolaemic female athlete using statin medication in combination with a lipid uptake inhibitor. Method Firstly, an observational cohort study was conducted on 19 recreational male (n=6) and female (n=13) athletes during a 95km trail run over three days. Pre-and post-stage and 24 and 72 h post-race concentrations of serum CPK, hsCRP, cortisol, cTnT, and osmolality (sOsm) as well as uMb, changes in body mass, delayed onset muscle soreness (DOMS) and thigh circumference (TC) were measured. Continuous recordings of heart rate (HR) and intestinal temperature (Tintest ) were made throughout each stage. In addition, a case report is included on one trained female endurance athlete currently being treated for familial hypercholesterolaemia with 20 mg Aspavor and 10 mg Ezetrol daily and not included in the above cohort, to investigate the degree of muscle damage and inflammation she experienced as a result of participation in the three-day event. Results: Heart rate ranged between 77 and 83% age-predicted-maximum (APmax) and Tintest between 36.1 and 40.2 ºC during the three stages. Significant rises in mean serum CPK, hsCRP, sOsm and blood neutrophil count reached peak concentrations of 1 488U/L, 8.91mg/l, 298mosm/L and 10.21 10^9/L (p≤0.001), respectively. No evidence of elevations in uMb and cTnT were detected. The stage-induced increments in DOMS correlated positively with CPK, r=0.71; 95% CI [0.62, 0.78]. TC decreased significantly post S1post and S2post (p≤0.05) and a maximum mean body mass loss of 3.09% (±1.04%) occurred during S2. There was no significant difference between nonsteroidal anti-inflammatory drug (NSAID) users and non-users in terms of serum CPK, hsCRP, cortisol, post race DOMS scores, running times, TC or sOsm (p>0.05). The post-pre change in sOsm during each stage correlated inversely with the changes in % body mass, r = -0.36, 95% CI [-0.57,-0.094] and the pooled data examining the relationship between the change of sOsm and change in serum CPK for the three stages (n=57), revealed an insignificant positive correlation (r= 0.034, 95% CI [-0.228, 0.291]. The maximum Tintest ranged between 38.3 º C and 40.2 º C and only exceeded 40º C in two of the 12 athletes monitored. The relationship between the change in Tintest and serum CPK was insignificant (p>0.05) for the 11 individuals from whom complete sets of data were available (r= 0.24, 95% CI [-0.42, 0.734]. In the hypercholesterolaemic athlete, the maximum serum CPK (665U/L), hsCRP (1.9mg/Ll) and cortisol (845nmol/L) concentrations corresponded with undetected uMb despite a maximum body mass loss of 4.5% Conclusion: Three consecutive days of 95km trail running resulted in low markers of muscle damage and inflammation, when compared to results obtained in previous single day road races of similar duration despite the maintenance of a heart rate above 77% APmax, Tintest rising above 39o C and mean body mass decrement of >2.0%. The unchanged concentrations of serum cTnT and uMb confirmed the low values of the markers of muscle damage and inflammation. An insignificant positive correlation between muscle damage and dehydration was noted. Furthermore the daily use of 0.4 mg/kg Atorvastatin in combination with 10mg Ezetrol did not result in the subject experiencing subjective myalgia, cramps, fatigue or increased markers of muscle damage following her participation in the trail run. / Thesis (M.Med.Sc.)-University of KwaZulu-Natal, 2012.

The purposes of this study is to determine: (a) the relationship between the dependant variables, (b) the relationship between the Borg pain scale and the performance tests, (c) the difference in performance between involved and uninvolved extremities, and (d) the effects of the three different therapeutic exercise treatments on selected performance tests and pain free isometric strength testing. Fifty subjects with physician diagnosed anterior knee pain (AKP), completed initial performance testing and 14 subjects completed initial testing, therapy and six weeks later final performance testing. The 14 subjects were randomly assigned to one of three therapeutic exercise treatment groups. The performance tests included; pain free isometric strength tests (90, 60, 45, and 15 degrees knee flexion), stair test, timed hop, triple hop, crossover hop, Figure 8 and Borg pain scale rating for each performance test. The results indicated a significant correlation between performance tests and pain free isometric strength tests. There was no relationship indicated between the performance tests, Borg pain scale ratings. The contrast between the injured and uninjured extremities performance test values of the fifty subjects that completed the initial testing indicated no significant (p< 0.05) difference. The results of this study indicated that there was no significant difference between the therapeutic exercise treatment groups. In conclusion, the three anterior knee pain treatments had no effect on strength and performance. / School of Physical Education

Background: Whole-body vibration (WBV) has been proposed as a viable alternative, or adjuvant to exercise for power development in athletes. More recently individualized frequency (I-Freq) has been introduced with the notion that individuals may elicit a greater reflex response to different levels (Hz) of vibration. Purpose: The aim of the study was to evaluate acute WBV as a feasible intervention to increase power in trained cyclists. Additionally, to evaluate the efficacy of utilizing I-Freq as an alternative to 30Hz, a common frequency seen in the literature. Methods: Twelve highly-trained, competitive male cyclists (age= 29.9 yrs ± SD 10.0; body height=175.4 cm ± SD 7.8; body mass= 77.3 kg ± SD 13.9) free of musculoskeletal injury or pathology participated in the study. The Wingate test for anaerobic power was administered on three occasions following a control of no vibration, 30 Hz, and I-freq. Measures of peak power (PP), average power (AP) and rate of fatigue were recorded and compared to the vibratory conditions using separate RM-ANOVA’s. Results: PP, AP, and rate of fatigue were not significantly impacted by 30 Hz and I-Freq vibration interventions (p > 0.05). Conclusion: Acute WBV using the parameters of the present study may not have been practical to elicit an increase in power as potential changes in the highly trained population may have been muted as a function of training status. / School of Physical Education, Sport, and Exercise Science

Preliminary normative standards are a tool clinical exercise specialists and health fitness instructors can use when interpreting muscular strength testing results. However, a challenge for professionals is evaluating an individual's one-repetition maximum (IRM) and relating that to others of the same age and gender, because there are no preliminary normative standards for 1RMs available when testing via free-weights and machines.This study conducted at Ball State University, Adult Physical Fitness Laboratory, examined results of muscular strength testing in order to obtain the normative muscular strength of adults. The purpose was to develop preliminary normative standards for strength of adults and to compare the 1RM weight an individual lifts between free-weights, Paramount, and Cybex machines. Seventy-nine healthy men and women between 18 and 79 years of age participated in the study. Subjects were tested on free weights, Paramount, and Cybex machines.Test results revealed preliminary normative standards for 1RM on free weights. Individuals were categorized in three age groups for the free-weight bench press and the Cybex (free-weight) Leg Press. The 18-23 year olds obtained a IRM mean (± Standard Deviation (SD)) of 200.6 + 32.8 lbs and 83.6 ± 18.5 lbs for men and women, respectively, for the free-weight bench press. The 43-59 year olds obtained a 1RM mean of 149.2 ± 41.8 lbs and 71.3 ± 8.6 lbs and the 60-79 year olds had a 1RM mean of 119.5 + 30.0 Ibs and 61.6 ± 15.6 lbs for men and women, respectively, for the free-weight bench press. The 18-23 year olds obtained a 1RM Cybex (free-weight) leg press mean of 484.9 + 58.0 lbs and 234.3 ± 67.5 lbs for men and women, respectively. The 43-59 year olds were able to obtain 1RM means of 444.4 + 84.9 lbs and 254.5 ± 51.7 lbs and the older subjects (60-79 years old) were able to obtain 1RM mean of 390.7 ± 98.6 lbs and 230.3 ± 76.6 lbs for men and women, respectively. Results were also documented in relative values by the amount of weight pushed divided by body weight for better comparison of individuals. Subjects generally lifted more weight on the Cybex (free-weight) leg press compared to the Cybex (machine) leg press. All subjects (N=79) had a mean and standard deviation of 294.9 + 87.7 lbs for the Cybex (machine) leg press (1RMs) and 343.4 ± 123.4 lbs on the Cybex (free-weight) leg press (1RMs). There was a significant difference between the Cybex (free-weight) leg press and the Cybex leg press (p<.001). The correlation for these two types of lifts was r=0.88. There was a significant difference between the free-weight bench press and the Paramount seated chest press (p<.001). The correlation for between the two types of lifts was r=0.93. / School of Physical Education, Sport, and Exercise Science

M.Tech. / Purpose: This study aims to determine whether adjusting the area of nerve root supply, or adjusting the attachment site of the latissimus dorsi muscle, will have an effect on the latissimus dorsi muscle and to which extend, with regards to strength and electromyographic (sEMG) activity. These effects were evaluated by measuring the latissimus dorsi .muscle strength using a Jamar dynamometer as well as sEMG readings of the latissimus dorsi muscle using a Neuro Trac ETS unit. Readings were taken prior to treatment on the first, third, and fifth consultations. Method: Forty five participants who met the inclusion criteria were stratified in number and gender between three groups of equal size (15 participants each). Group 1 received lower cervical adjustments (C5 - C7), group 2 received lower thoracic and lumbar adjustments (T6 - L5) and group 3 received detuned ultrasound therapy on the latissimus dorsi muscle. Group three served as the control group. Participants were treated four times out of a total of five sessions, over a maximum three week period Procedure: Objective data was collected at the beginning of the first and third session, as well as on the fifth consultation by means of a Jamar dynamometer and a Neuro Trac ETS unit in order to assess the functionality of the latissimus dorsi muscle. Analysis of collected data was performed by a statistician. Results: Statistically significant improvement in the dynamometry readings of both the experimental groups were noted when compared to that of the control group. The results of the sEMG activity were variable. Conclusion: The results show that adjusting the area of nerve root supply as well as adjusting the attachment site of the latissimus dorsi muscle are effective treatment protocols (as demonstrated statistically) in increasing strength of the latissimus dorsi muscle. The results suggest that adjusting the attachment site of the latissimus dorsi muscle is most effective in increasing the strength of the latissimus dorsi muscle. The results of the sEMG activity were variable and there were no evidence supporting the effectiveness of adjusting the area of nerve root supply versus adjusting the attachment site ofthe latissimus dorsi muscle on sEMG activity.

Muscle strength has been identified as an important contributor to athletic performance. Little attention however, has been paid to the specific relationship between peak isokinetic muscle strength and sprint starting performance. The aim of this study was to determine the influence of an adapted front knee angle, as determined by isokinetic assessment (the angle of peak torque production), on starting performance. Sixteen track sprinters, of elite-national or competitive-regional standard, were asked to perform eight sprints over 50m using four separate starting techniques. Technique 1 featured the athlete’s usual starting preferences while Techniques 2, 3 and 4 featured a standardised set of starting preferences with experimental modifications of the front knee angle in the “set” position. Isokinetic muscle strength was measured at slow (60°/s) and fast (240°/s) test speeds in order to determine the angle of peak torque production for concentric knee extension of each subject’s lead leg. Using one-way analysis of variance (ANOVA) and Post Hoc analysis (LSD), no significant differences (p>0.05) were observed between the experimental techniques for: block time, force-time measures during block time, sprint times, sprint velocity and acceleratio n measures at intervals up to 50m. Significant differences (p<0.05) were however observed between reaction times for the experimental techniques. Slower reaction times are most likely due to increased upper body pretension, resulting from the increased hip elevation seen for these techniques. The results indicate that increased hip elevation may have delayed the initiation of the relevant motor response required to affect an optimal sprint start. Technique 1 resulted in the shortest reaction times, shortest block times, fastest sprint times and greatest sprint velocities for all four techniques. This result was possibly due to the athlete’s experience with, and repeated use of, this technique. The experimental techniques therefore provided no added advantage over the subject’s preferred starting technique and did not significantly optimise sprint starting performance. The results show that modification of the front knee angle had no significant influence on sprint starting performance and sprint running ve locity or acceleration patterns up to 50m. Using Pearson’s Correlation Coefficient to determine the strongest correlations between isokinetic knee strength and sprint starting performance, analysis revealed that the strongest relationships were found between sprint starting performance expressed as acceleration and isokinetic knee strength expressed as relative peak torque and absolute peak torque. For Technique 1 the strongest correlation was found between acceleration (30m - 40m) and relative peak torque as measured at a test speed of 240°/s (r = 0.62). For the remaining experimental techniques, the strongest correlation was found between acceleration (10m - 20m) and relative peak torque as measured at a test speed of 60°/s (r = 0.53) for Technique 2, between acceleration (40m - 50m) and peak torque measured at a test speed of 60°/s (r = 0.72) for Technique 3, and between acceleration (0m - 5m) and peak torque as measured at a test speed of 240°/s (r = 0.71) for Technique 4. These results suggest that isokinetic muscle strength does not correlate strongly with sprint starting performance and that additional factors, such as neuromuscular organisation and muscle fibre typing, possibly make a greater contribution to optimal sprint starting performance.