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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Influence of COX-inhibitors on myofiber hypertrophy and capillarization in response to resistance exercise in older individuals / Influence of COX inhibitors on myofiber hypertrophy and capillarization in response to resistance exercise in older individuals / Influence of cyclooxygenase-inhibitors on myofiber hypertrophy and capillarization in response to resistance exercise in older individuals

Brower, Brooke E. 20 July 2013 (has links)
Access to abstract permanently restricted to Ball State community only. / School of Physical Education, Sport, and Exercise Science
202

The effect of a cyclooxygenase-2 inhibitor on human mixed muscle protein synthesis after acute resistance exercise

Burd, Nicholas A. January 2007 (has links)
We have previously shown that non-specific blockade of the cyclooxygenase (COX) enzymes in skeletal muscle eliminates the normal increase in muscle protein synthesis following resistance exercise. The current study tested the hypothesis that this COX-mediated increase in postexercise muscle protein synthesis is specifically regulated by the COX-2 isoform. Sixteen males (23 ± 1 yr, 177 ± 2 cm, 81.5 ± 3.4 kg) were randomly assigned to one of two groups that received three doses of either a specific COX-2 inhibitor (celecoxib; 200 mg per dose, 600 mg total) or a placebo during the 24 hours following a single bout of resistance exercise with the knee extensors. Skeletal muscle fractional synthesis rate (FSR) was measured at rest and 24 hours postexercise using a primed constant infusion of [2H5]phenylalanine coupled with muscle biopsies of the vastus lateralis. Mixed muscle FSR was increased following exercise to a greater extent (206%, P<0.05) in the COX-2 group (0.052 ± 0.014 %Ih) as compared with the placebo group (0.017 ± 0.007 %Ih). These results suggest that the specific inhibition of the COX-2 isoform in human skeletal muscle causes a compensatory response in muscle protein synthesis. These data also highlight the involvement of the cyclooxygenase pathways in the regulation of muscle protein synthesis following resistance exercise. / School of Physical Education, Sport, and Exercise Science
203

The effect of three selected exercises on electromyographic root mean square values and vastus medialis oblique to vastus lateralis ratio

Myer, Gregory D. January 1998 (has links)
The primary purpose of this study was to determine the ratio of activation between the VMO and VL while performing three selected knee exercises (drop squat, modified lateral squat, Muncie Method). Additionally, the data was analyzed to determine if a correlation existed between the muscle's activation rate per set and whether or not the rates are affected by Q-angle or gender. Twenty Ball State University subjects (10 male, 10 female) who were asymptomatic to Patellofemoral Syndrome (PFS), provided electroymyographic (EMG) data while performing the three selected exercises. A one-way ANOVA found no statistical significance (p=0.500) on any of the tested variables except the Drop Squat VL Root Mean Square (RMS). Significant correlations were found between: VL RMS to set number during drop squat, and VMO and VL RMS to set number during Muncie Method performance. Based on the results of this study, each of these exercises could be used to selectively strengthen the VMO in treatment of PFS. / School of Physical Education
204

The effects of resistance training on golf performance and physiological stress response during competition in intercollegiate golfers

Doan, Brandon K. January 2002 (has links)
Two investigations were conducted with collegiate golfers for separate, but related purposes. 1) To investigate the effects of a physical conditioning program (strength, power and flexibility training) on clubhead speed, consistency, and putting distance control. 2) To investigate the effects of 36 continuous holes of competitive golf on testosterone and cortisol response and their relation to performance.Study #1: Subjects were ten men and six women NCAA Division I golfers. Supervised strength, power, and flexibility training was performed 3 times per week for 11 weeks. Golf ball launch conditions, putting distance control, strength, power, and flexibility tests were conducted before and after training. Significant (p < 0.05) increases were noted for all strength, power, and flexibility tests. Clubhead speed increased significantly (1.6%) from pre to post training, equating to a 4.9-meter increase in driving distance. No significant differences were observed for clubface-angle or launch-angle deviation. Putting distance performance significantly improved for the men-only group (29.6%). Significant (p < .05) correlations resulted between clubhead speed and rotational power (r = 0.86) for the men-only group. Qualitative video analysis did not show any consistent trends in swing mechanics alterations. Eleven weeks of physical conditioning increased clubhead speed without a negative effect on consistency or putting distance control in intercollegiate men and women golfers. Study #2: Subjects were eight NCAA Division I men golfers. Saliva samples were taken 45 minutes prior to the round and after each hole during a 36-hole competition. Time matched baseline samples were collected. Six and 36-hole area under the curve (AUC) values were calculated for endocrine measures. Salivary cortisol increased by 111% (p < 0.05) during competition compared to baseline. Testosterone-to-cortisol ratio was significantly lower (45%) throughout the competition compared to baseline. Significant (p < 0.05) correlations resulted between: 36-hole AUC testosterone-to-cortisol ratio difference and 36-hole score (r = 0.82), CSAI-2 somatic anxiety and pre-round cortisol (r = 0. 81), testosterone (r = -0.80), and testosterone-to-cortisol ratio (r = -0.72). These results indicate a significant hormonal strain during 10 hours of competitive golf, low TIC ratio relation with low golf scores, and CSAI-2 relation with endocrine measures. / School of Physical Education
205

The impact of gender and chronic resistance training on human patellar tendon dry mass, collagen content, and collagen cross-linking

Lemoine, Jennifer K. January 2008 (has links)
Collagen content and cross-linking are believed to be major determinants of tendon structural integrity and function. Gender and chronic resistance training have been shown to alter tendon function, and may also alter these key structural features of tendon. Patellar tendon biopsies were taken from untrained men (M, n=8, 25±1 y, 1RM: 53±3 kg), untrained women (W, n=8, 23±2 y, 1RM: 29±2 kg), and resistance-trained (10±1 y trained) men (RTM, n=8, 24±2 y, 1RM: 71 ±6 kg). Biopsies were analyzed for dry mass, collagen content, and collagen cross-linking (hydroxylysylpyridinoline, HP). Tendon dry mass was significantly lower in women than men (M: 376±8, W: 343±5 µg dry mass/mg tendon wet wt, P<0.01), and was not influenced by chronic resistance training (RTM: 364±20 µg dry mass/mg tendon wet wt, P>0.05). The lower tendon dry mass in women reduced (P=0.08) collagen content per tendon wet weight (M: 339±14, W: 306±11 µg collagen/mg tendon wet wt). Collagen content of tendon dry mass was not influenced by gender (P>0.05) or resistance training (P>0.05) (M: 903±38, W: 892±29, RTM: 881±43 !,g collagen/mg tendon dry mass). Similarly, cross-linking of collagen was not impacted by gender (P>0.05) or training (P>0.05) (M: 401±47, W: 418±35, RTM: 424±38 mmol HP/mol collagen). In women, the overall lower amount of collagen per tendon wet weight may explain gender differences in tendon function, while collagen content and cross-linking of the dry mass are remarkably consistent across gender and training status. / School of Physical Education, Sport, and Exercise Science
206

Influence of gender and muscle origin on skeletal muscle gene expression at rest and following maximal resistance exercise

Louis, Emily S. January 2008 (has links)
The aim of this investigation was to compare the acute anabolic and catabolic responses of male and female vastus lateralis (VL) and soleus (SOL) muscles in response to resistance exercise (RE). Muscle biopsies from the VL of 7 males (26±3 y, 75±8 kg) and 7 females (25±3 y, 59±5 kg) were obtained before, and 2 and 6 h after 4 x 7 supine-squat, and 4 x 14 calf-press exercises at maximal effort using inertial ergometry. The mRNA levels of select myogenic (MyoD, myogenin, MRF4), proteolytic (atrogin-1 , MuRF-1), myostatin, and inflammatory (IL-6, -8, -15) genes were quantified using real-time RT-PCR. Male VL vs SOL: The SOL had higher basal mRNA levels of myogenic, proteolytic, and inflammatory genes. After exercise, the myogenic response was similar between the VL and SOL. Both muscles increased MuRF-1 similarly at 2 h, whereas 6 h post-RE proteolytic gene expression (GE) was suppressed in the VL but not in the SOL. The SOL had a reduction in myostatin GE, and a more robust inflammatory response compared to the VL. These findings indicate a more favorable growth response in the VL. Gender comparisons: VL – Basally, the male VL had higher levels of myogenic, proteolytic, myostatin, and inflammatory mRNA compared to the female VL. After exercise, both genders increased myogenic GE similarly. Both genders increased MuRF-1 initially, with females also increasing atrogin-1 and myostatin post-RE. At 6 h, males decreased proteolytic GE to below basal levels. Females also had a greater inflammatory response than males. These findings indicate a greater growth response to RE in the male VL as compared to the female VL. SOL – After exercise, both genders increased myogenic GE in the SOL, but only males increased MyoD expression. Males increased MuRF-1 mRNA but decreased myostatin GE, while females decreased atrogin-1. The inflammatory response was similar between males and females. Despite the modest differences, the net response of the female and male SOL was similar, and indicated a molecular response slightly favorable for growth. / School of Physical Education, Sport, and Exercise Science
207

A minimalistic model of resistance training : effects on skeletal muscle function during unloading

Schulze, Kimberley E. January 1999 (has links)
Since astronaut time and energy are at a premium, effective countermeasures must be designed to maximize benefits while minimizing time/energy cost. Therefore, our intent was to design and evaluate a low volume, high intensity resistance training program (RTP) on the preservation of knee extensor and plantar flexor size, strength and neuromuscular function in response to unloading. A total of 32 subjects participated. Sixteen men underwent 21 days of unilateral lower limb suspension (ULLS) and were assigned to control (no RTP) (ULLS-CON, n=8) or countermeasures (ULLS-CM, n=8). The remaining subjects were ambulatory for 21 days and were assigned to no RTP (n=8) or countermeasures (n=8). Countermeasure subjects performed RTP every third day during the suspension period (total=6). The RTP consisted of 2 maximal isometric contractions (MVC), 1 set of 10 concentric/eccentric isotonic repetitions, and 1 set to exhaustion, at 80% of 1-repetition maximum (1RM). There was no change in muscle function in ambulatory subjects. Whole muscle cross sectional area (CSA) measured by computed tomography (CT) decreased 7% (thigh) and 7.5% (calf) in ULLS-CON (p<0.05), and was unchanged in ULLS-CM. MVC decreased 16.5% in both quadricep and calf muscles in ULLS-CON (p<0.05) and increased 6% in the quadricep of ULLSCM (p<0.05). Maximal concentric (CNC) and eccentric (ECC) isokinetic strength decreased an average of 18% and 17% in the knee extensors and plantar flexors of ULLS-CON, respectively (p<0.05) and was unchanged in ULLS-CM. 1RM decreased 16% in both quadricep and calf of ULLS-CON (p<0.05) and was unchanged in ULLSCM. Knee extensor work capacity, evaluated during 30 maximal CNC contractions (3.14 rad•sec-'), decreased 18% in ULLS-CON (p<0.05). Neural activation of knee extensors and plantar flexors was measured by electromyography (EMG). Submaximal v.lat, v.med, gast and sol EMG increased in ULLS-CON (p<0.05) and was unaltered in ULLSCM. Maximal EMG decreased 20% and 26% in v.1at and v.med, respectively in ULLSCON (p<0.05). ULLS-CM showed a 15% and 28% increase in v.med and gast maximal EMG (p<0.05). These data suggest knee extensor and plantar flexor muscle size, strength and neuromuscular function were preserved during unloading using a low volume, high intensity RTP performed every third day. / School of Physical Education
208

Knee Muscle Activation Characteristics During Closed Kinetic Chain Directional Loading in Healthy Young Males and Females

Flaxman, Teresa 30 March 2011 (has links)
Neuromuscular control is believed to play an essential role during dynamic knee joint stabilisation. Evaluation of voluntary muscle action can be delineated as support strategies against external loading moments (Lloyd & Buchanan, 2001). The aim of this study was to determine if males and females exhibit differences in knee muscle action and cocontraction during voluntary isometric closed kinetic chain force generation in various directions in the horizontal plane representative of applied loads transverse to the long axis of the shank. Twenty-six healthy young adults (13 male, 13 female) stood with their dominant leg in a boot fixed to a force platform. A force target matching protocol required subjects to position a cursor (projected on a video screen) over a target and maintain the position for one second. To control the cursor, loads were applied against the force platform with their dominant leg to produce various combinations of anterior-posterior, medial-lateral loads while maintaining constant inferior-superior loads. A successful target match required a normalised force magnitude of equal effort for each subject and target location which triggered the recording of electromyography (EMG) for eight muscles crossing the knee joint. EMG was normalised to percent maximum voluntary isometric contraction. A mean magnitude of muscle activation, mean direction of muscle activation and a muscle specificity index was determined using EMG vectors. In addition, cocontraction indices were also computed for antagonist muscle pairs. Based on similar previous research, it was hypothesised that females would have greater quadriceps and hamstrings coactivation, greater muscle activation magnitudes, lower specificity for the quadriceps than males and no difference in hamstring characteristics. In our study, females significantly cocontracted their vastus lateralis and lateral gastrocnemius muscles to a greater degree than males (p=0.001). No significant differences were observed across sexes for the cocontraction of quadriceps and hamstrings or the lateral quadriceps and gastrocnemius muscles. Females displayed significantly lower specificity than males in their semitendinosus (p=0.025) and tensor fascia lata (p=0.012) activity patterns, greater magnitude of muscle activation in their lateral gastrocnemius (p=0.002) and tensor fascia lata (p<0.003) and no statistical difference in the other muscles. Furthermore, the activation patterns in our study grossly differed from previous open kinetic chain force target matching. These findings indicate that healthy young males and females have differences in their knee muscle control strategies and that knee muscle recruitment patterns differ during weight bearing and non-weight bearing tasks.
209

Sportininkų po ūmios čiurnos raiščių traumos izometrinės eversijos ir inversijos jėgų pokyčių vertinimas reabilitacijos eigoje / Evaluation of isometric eversion and inversion strength changes during rehabilitation among sportsmen after acute ankle sprain injury

Tankevičius, Gediminas 04 September 2014 (has links)
Disertacijoje įvertinta 144 sportininkų, patyrusių ūmią čiurnos raiščių traumą, čiurnos funkciją atspindinčių rodiklių kaita reabilitacijos eigoje. Greta įprastinių čiurnos funkciją atspindinčių rodiklių, tokių kaip čiurnos skausmas, patinimas, subjektyviai vertinama čiurnos funkcija, šiame darbe taip pat buvo vertinama čiurnos izometrinė eversijos ir inversijos jėga. Kadangi izometriniai jėgų matavimai buvo atliekami ūmiuoju čiurnos raiščių pažeidimo periodu, tai buvo vertinamas ir šių matavimų poveikis čiurnos funkcinei būklei. Darbe taip pat buvo vertinamas ir palyginamas įprastinės ir paspartintos kineziterapijos programos efektyvumas, nustatomos atskirų rodiklių, atspindinčių čiurnos funkcinę būklę, tarpusavio sąsajos ir jų reikšmė prognozuojant čiurnos funkcijos atsigavimą. Darbe įrodyta, kad taikant paspartintos kineziterapijos programą, atsižvelgiant į reabilitacijos eigoje įvertintus izometrinės eversijos ir inversijos jėgų rodiklius, galima pasiekti didesnį reabilitacijos efektyvumą. Taip pat nustatyta, kad izometrinės jėgos matavimai neturi įtakos čiurnos funkcinei būklei, o šių matavimų metu gauti duomenys objektyviai atspindi reabilitacijos eigą ir pagal tai galima dalinai prognozuoti čiurnos funkcijos atsigavimą. / In the dissertation, an analysis of ankle‘s function indicators as well as their changes during the rehabilitation of 144 sportsmen after acute ankle sprain was performed. In addition to conventional indicators of ankle function (lower extremity scale score, pain, and swelling) in this study the indicators of isometric ankle eversion and inversion strength were assessed. Since the isometric strength measurements were performed during acute stage after ankle sprain, the impact of these measurements to functional status of the ankle and recovery course was evaluated. Additionally, in this study the efficacy of standard and accelerated home-based exercise program were assessed and intercorrelations of ankle function indicators and their predictive value for ankle recovery were established. It was shown, that isometric measurements of eversion and inversion strength do not influence ankle‘s functional state and course of rehabilitation among sportsmen after acute ankle sprain. Accelerated home-based exercise program based on isometric testing had a trend of better improvement of ankle function. It was also found that the isometric eversion and inversion strength measurement does not affect the functional state of the ankle, and the data obtained during these measurements objectively reflects the course of rehabilitation and can predict the recovery of ankle function.
210

Effects of load and training pattern on acute neuromuscular responses

Goodale, Tyler Logan 19 February 2010 (has links)
The purpose of this study was to examine the effects of two different repetition maximum (RM) loads and training patterns on acute neuromuscular responses. Twenty one resistance-trained males performed 4 protocols of dynamic constant external resistance exercise, involving elbow flexors, that manipulated either load (5RM, 10RM) or training pattern (TP). For TP the subjects completed 4 sets of exercise with 3 min rest between exercise performing each set to fatigue which produced a decrease in the number of repetitions with each subsequent set (DTP); the second testing pattern involved performing the same number of sets and repetitions to the DTP but in a reverse order so that the repetitions ascend with each subsequent set (ATP). Volume load (VL) was equated for both patterns but the set in which the greatest VL was achieved occurred at different times in the workout, either in the 1st (DTP) or 4th (ATP) set of the exercise. Both TPs were conducted with a 5RM and 10RM load. Fatigue was assessed by changes in maximum voluntary isometric contraction (MVIC), motor unit activation (MUA), muscle twitch characteristics (peak twitch [PT], time to peak twitch [TPT], and 1/2 relaxation time [1/2 RT]). All protocols produced significant changes pre to post fatigue (p A).05) for MVIC, MUA, PT, 1/2RT, and TPT. 5RM/ATP, 10RM/DTP, and 1 ORM/ATP protocols produced significant changes in MUA. PT was found to be significantly different across loads. The results indicate that central fatigue is independent of load and pattern whereas peripheral fatigue appears to be dependent on load.

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