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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.
291

Isokinetic muscular strength and endurance of active men over age 50 using different training protocols

Jordan, Shawn D. 30 July 1991 (has links)
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
292

Styrkeförhållandet mellan knäflexorer och knäextensorer

Gustavsson, Robert, Eklund, Fredrik January 2011 (has links)
Bakgrund: Inom forskningen studeras styrkeförhållandet i lårets muskler och anges ofta som flexor/extensor kvot (F/E-kvot). Ett sätt att mäta denna kvot är att använda isokinetiska styrketest.  Forskningen är inte överens om ett optimalt styrkeförhållande i denna muskulatur eller om för stor styrkeskillnad kan ge upphov till skada. Om en optimal kvot kan fastställas är det intressant i ett förebyggande och rehabiliterande syfte.  Syfte: Att beskriva och jämföra F/E-kvoten hos en grupp manliga fotbollsspelare med en grupp fysiskt aktiva män mellan 16 och 25 år. Metod: Mätning av maximal isokinetisk styrka i knäledens flexor och extensormuskler genomfördes med Genesis Single. Resultat: Studien fann en F/E-kvot hos fotbollsspelarna på 78,2 % på höger ben och 77 % på vänster ben. Jämförelsegruppen hade en F/E-kvot på 73,7 % på höger ben och76,4 % på vänster ben. Utifrån detta kunde man inte finna någon signifikant skillnad mellan de båda grupperna Slutsats: Studien fann ingen signifikant skillnad i F/E-kvot i höger respektive vänster ben mellan en grupp fotbollsspelare och jämförelsegrupp. Vidare forskning om reliabilitet och validitet med Genesis Single som mätinstrument bör utföras innan fler studier utförs med maskinen. / Background: The kneeflexor and kneextensor muscle strength ratio (F/E ratio) is a widely researched area where isokinetic tests are often used. There seems to be little consensus regarding the optimal ratio and also whether a low ratio increase the risk of injury. It would be interesting from a preventive and rehabilitative stand point if an optimal ratio could be decided upon.  Objectives: To compare the F/E ratio between a group of 16-25 year old soccer players and a group of physically active males. Methods: Isokinetic maximal strength in kneeflexors and kneextensors were measured with Genesis Single. Results: The ratio of the soccer players was 78,2 % in the right leg and 77 % in the left. The comparison group was found to have a ratio of 73,7 % in the right leg and 76,4 % in the left leg. There were no significant differences between the two groups. Conclusions: No significant differences could be determined between the two groups. Genesis Single needs to be further investigated with regards to its reliability and validity.
293

Pilates Exercise Positively Affects Balance, Reaction Time, Muscle Strength, Number Of Falls And Psychological Parameters In 65+ Years Old Women

Babayigit Irez, Gonul 01 November 2009 (has links) (PDF)
Physical changes such as impairment flexibility, balance, muscle strength and reaction time occur with aging. Regular lifetime physical activity appears to delay these factors. The purpose of this study was to determine if 12 weeks Pilates exercise could improve dynamic balance, reaction time, flexibility, muscle strength, bone density and quality of life in 65+ years old women and to investigate the changes of these parameters in a year follow up. Thirty out of a hundred women living in a Residential House in Ankara were enrolled in the study. Participants attended a 12-week series of one-hour Pilates exercise meeting three times per week. Dynamic balance, flexibility, reaction time, number of falls, muscle strength, bone mineral density, quality of life and anxiety were measured before and after exercise. Results showed that flexibility, balance, simple and choice reaction time, muscle strength, number of falls, quality of life and beck anxiety scores significantly improved in the exercise group. In addition, after a year of follow up, there were prominent decreases in simple reaction time and muscle strength, choice reaction time, number of falls and bone mineral density in control group while there were no evident changes in exercise group. Furthermore, there were significant relationships of balance with muscle strength, choice reaction time and anxiety.As the result of this study, it can be concluded that Pilates exercise can be efficient for preventing falls, increasing muscle strength and dynamic balance, flexibility, reaction time and decreasing anxiety while increasing quality of life. In the long term, Pilates exercise may have very positive effects on bone mineral density.
294

The effects of a 10-week strength training program on explosive strength, muscular endurance and aerobic capacity in 13- to 15-year-old boys /

Lam, Siu-wah, Eric. January 2001 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 67-84).
295

Investigations of the neuromuscular response during and following elite maximum strength and power type resistance exercise

Brandon, Raphael January 2011 (has links)
The thesis aimed to analyse the acute neuromuscular (NM) response during and following maximum strength and power training methods. The primary aim of study one was to establish the reliability of biomechanical and surface electromyographic (sEMG) measurements during barbell squat exercise. This would enable the subsequent studies to precisely assess muscle activity and mechanical power during barbell resistance exercise sessions. Nine male well-trained subjects performed squat exercise on three separate trial days. Each trial comprised one set of squat at 50, 75 and 100% of 3RM load. Synchronous recordings of knee joint kinematics from a flexible electrogoniometer, barbell displacement from a single linear position transducer and quadriceps sEMG amplitude were made. The mean maximum knee angle during squat was recorded at each load, and the overall inter-trial coefficient of variation (CV) was 5.5%. Mean concentric repetition power was processed from displacement data and derived into force and velocity values. The overall inter-trial CV for mean power was found to be 8.4%. The raw sEMG signal was processed into root mean square (RMS) amplitude and normalised to values taken from pre-trial knee extension maximum voluntary contractions (MVC). RMS amplitude was processed for the whole concentric phase and a 200 ms time interval at a knee angle of 70°, which matched the knee angle used during MVC. Inter-trial CV for RMS amplitude from the concentric phase and 70° knee angle were 7.2% and 16.4% respectively. There were no differences in RMS amplitude, maximum knee angle or mean power across trial days. It was concluded there was acceptable reliability for all three measurements (CV < 10%), if RMS amplitude was processed from the concentric phase. Based upon the measurement reliability, the analysis system was considered suitable for monitoring power and sEMG during barbell exercise. The second study aimed to establish the reliability of muscle fibre conduction velocity (MFCV) measurements during barbell squat. This was of interest, as MFCV may provide useful information of NM recruitment and fatigue processes during resistance exercise. The study was also used as a preliminary investigation of MFCV response, in comparison to RMS amplitude, to increasing fatigue and load during squat exercise. Nine well-trained male subjects performed a series of exercises on two separate trial days. Each trial comprised isometric knee extensions at 50, 75 and 100% of MVC force, followed by barbell squats at 50, 75 and 100% of 3RM, and then a maximal bout of squat jumps at 50% 3RM load, performed until failure. sEMG measurements were recorded from a four-electrode array, secured upon the vastus lateralis. Normalised RMS amplitude was processed as above, and MFCV was processed from the inter-electrode distance and time delay between two double differentiated and correlated signals, using bespoke software. The overall value of MFCV during squat was 5.8 m.s-1. The inter-trial CV for MFCV was 9.6% during squat and 12.1% during squat jump. Based upon acceptable reliability of 10%, MFCV measurements from barbell squats were considered reliable. As expected, MFCV significantly increased with each knee extension force level (4.7 ± 1.4, 5.6 ± 1.5 and 6.2 ± 1.8 m.s-1) (p<0.01), along with RMS amplitude (p<0.0001). No differences in MFCV were found between squat loads, whilst RMS amplitude significantly increased with load (p<0.0001). Power (1920 ± 143 versus 1407 ± 254 W) and MFCV (5.7 ± 1.4 versus 4.6 ± 1.0 m.s-1) significant decreased (p<0.001) from the start to the end of the squat jump trial, with RMS amplitude unchanged. Therefore, MFCV altered with increasing fatigue, but not load, during dynamic squat exercise. It was concluded that MFCV provides useful and reliable data for acute fatigue investigations of barbell resistance exercise, in addition to sEMG amplitude measures. The following three investigations compared NM responses during and following maximum strength and power type resistance exercise sessions with different exercises, loads and movement speeds. The sessions were designed to represent elite athlete training practices, to help inform the optimisation of resistance exercise programmes. The first of these studies aimed to compare NM response to a typical maximum strength session performed with barbell squat or deadlift exercise. The purpose was to assess if technical differences between the exercises, influenced the acute NM response. Nine elite trained weightlifters performed the trial sessions of five sets of five repetitions on separate days. Normalised RMS amplitude, MFCV and power was continually measured during exercise repetitions, using the methods established above. NM function was assessed pre- and post- sessions using MVC force, central activation ratio (CAR) from superimposed stimulation during MVC, and jump performance (CMJ). The exercises were performed with subjectively matched load levels, corresponding to active muscle RPE = 17 (Borg scale), and also with controlled lifting speed. However, the squat load was lowered and raised upon the lifter’s back, whilst deadlift load was grasped in the hands, raised from the floor and then dropped. Repetition mean power was unchanged within and across sets of both sessions. Repetition RMS amplitude significantly increased (p<0.001) within sets of squat and deadlift, whilst a significant interaction between sessions and set (p<0.001) demonstrated RMS increased more during squat. Furthermore, a significant reduction in repetition MFCV was found within sets of squat (p = 0.034), but not deadlift. This suggests that motor unit activation increased during both exercises, as a response to the task of maintaining power during repetitions of whole body lifting. However, acute fatigue within squat sets led to additional increased activation as a NM compensation strategy. No pre- versus post- session differences were found for MVC, CAR or CMJ; suggesting minimal change in NM function occurred following five sets of maximum strength type resistance exercise, in well-trained subjects. The primary aim of the second study was to compare NM response and 24-hour recovery following barbell exercise maximum strength and power type sessions. The purpose was to specifically establish the degree and nature of NM response, as previous findings were unclear and barbell exercise sessions of this type have not been compared. 10 elite sprint athletes performed sessions comprising squat, split squat and push press, with four sets x repetitions per exercise. The maximum strength session exercises involved loads corresponding to active muscle RPE = 17 (Borg scale) and metronome controlled movements. The power session exercises used 30% of the maximum strength barbell load, performed as fast as possible. Repetition sEMG and power was monitored throughout each session, as above. NM function was assessed, pre-, post- and 24-hour post- each session, using the same tests as above. However, evoked peak twitch force (Pt) was also included to the pre- and post- assessments. Overall, the maximum strength session involved greater total work (p = 0.008), but lower mean power during exercise repetitions (p<0.001) in comparison to the power session. MVC and Pt force values both significantly decreased (p<0.05) pre- versus post- both sessions. However, MVC reduced more following maximum strength session (p<0.01). CAR and CMJ were unchanged post-both sessions and no differences were found between pre and 24-hour post session NM tests. The decreased Pt but not CAR findings, suggest peripheral fatigue explains the reduced force generation capacity following maximum strength and power sessions, contrary to previous resistance exercise session findings. Up to 24-hours may be required to recover force generation capacity following this volume of resistance exercise.
296

Comparison of power grip and lateral pinch strengths between the dominant and non-dominant hands for normal Chinese male subjects ofdifferent occupational demand

Lau, Wai-shing, Vincent., 劉偉誠. January 2001 (has links)
published_or_final_version / Medical Sciences / Master / Master of Medical Sciences
297

Validation of the 60-second chair rise as a measure of physical function in patients with non-small cell lung cancer

Pereira, Lucy. January 2008 (has links)
Yearly, 22, 200 Canadians are diagnosed with lung cancer, with 80-85% of the cases being non-small cell lung cancer (NSCLC). With diagnoses being predominantly in the advanced stages, prognosis is poor and quality of life (QoL) becomes the focus of treatment. The main symptom cachexia, issues a loss of strength and impacts on an important aspect of QoL, physical function. Physical function is predominately assessed subjectively. Lately performance-based measures are gaining in popularity. One performance measure, the chair rise test, has not been validated in the NSCLC population and was the objective of this study. / Subjects completed the chair rise test, 6MWT, hand grip, and the SF-36 pre and post chemotherapy. Evidence for construct and discriminant validity but not predictive validity was provided for the chair rise test. The 60-second chair rise may be too strenuous for persons with severe disability but a standardized timed-based chair rise test is needed.
298

Skirtingų kineziterapijos programų poveikis sergant kelio sąnario osteoartritu / The impact of various physiotherapy programs on the knee osteoarthritis

Darbutas, Tomas 16 August 2007 (has links)
Tyrimo problema: sergant kelio sąnario osteoartritu atsiranda skausmas, apsunkinama kasdieninė veikla, trinka pusiausvyra, padidėja griuvimo rizika. Siekiant pagerinti pusiausvyrą ir sumažinti griuvimų riziką, analizavome kaip įvairios kineziterapijos programos veikia pagyvenusių žmonių, sergančių kelio sąnario osteoartritu, šlaunies raumenų jėgą, statinę ir dinaminę pusiausvyrą bei skausmą. Tyrimo objektas: pusiausvyros, raumenų jėgos ir skausmo pokyčiai taikant skirtingas kineziterapijos programas. Tyrimo tikslas: nustatyti skirtingų kineziterapijos programų poveikį ligoniams sergantiems kelio sąnario osteoartritu. Tyrimo uždaviniai: 1. Nustatyti pusiausvyros kaitą taikant sąnarių mobilizaciją, TENS ir fizinius pratimus. 2. Nustatyti šlaunies raumenų jėgos kaitą taikant sąnarių mobilizaciją, TENS ir fizinius pratimus. 3. Nustatyti pusiausvyros kaitą taikant tik TENS ir fizinius pratimus. 4. Nustatyti šlaunies raumenų jėgos kaitą taikant tik TENS ir fizinius pratimus. 5. Įvertinti skirtingų kineziterapijos programų efektyvumą. Tyrimo hipotezė: manome, kad didžiausią teigiamą poveikį pusiausvyros, šlaunies raumenų jėgos ir skausmo kaitai turi ankstyvas sąnarių mobilizacijos, TENS bei fizinių pratimų taikymas. Taikant minėtus metodus atskirai, poveikis pusiausvyrai, šlaunies raumenų jėgai ir skausmui turėtų būti mažesnis arba visai nepasireikšti. Tyrimo metodai ir organizavimas: tyrimas atliktas VšĮ Kauno slaugos ligoninėje 2005-2007 metais. Tyrime dalyvavo asmenys, sergantys... [toliau žr. visą tekstą] / Problem of study: osteoarthritis of knee joint causes pain, aggravates everyday activities, disconcerts balance, and increases the risk of fall. Aiming to improve balance and to decrease the risk of falls, we analyzed how various programs of physiotherapy influence the strength of thigh muscles, static and dynamic balance, and pain of elderly with knee osteoarthritis. Object of study: changes of balance, muscle strength and pain after application of various programs of physiotherapy. Aim of study: to determine the impact of various physiotherapy programs to the patients with knee osteoarthritis. Goals of study: 1. To determine the change in balance, when the joint mobilization, TENS and physical exercises are applied. 2. To determine the change in the thigh muscles strength, when the joint mobilization, TENS and physical exercises are applied. 3. To determine the change in balance, when TENS and physical exercises alone are applied. 4. To determine the range of thigh muscles strength, when TENS and physical exercises alone are applied. 5. To evaluate effectiveness of various physiotherapy programs Hypothesis of study: we believe that the biggest positive impact on the change of balance, strength of thigh muscles and pain has the combination of early joint mobilization, TENS and physical exercises. While applying all those methods separately, the impact on the change of balance, strength of thigh muscles and pain is lesser or even doesn’t emerge. Methods and organization of... [to full text]
299

Muscle damage and inflammation following a three-day trail run.

Denissen, Emmerentia C. January 2012 (has links)
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.
300

Förändring av olika fysiologiska parametrar vid styrketräning hos äldre

Nienkerk, Andrée January 2013 (has links)
Sammanfattning Syfte och frågeställningar. Syftet med denna studie var att på äldre personer studera olika fysiologiska parametrar före och efter en period på åtta veckor med styrketräning som utförs tre gånger i veckan. Frågeställningarna var: Hur påverkas statisk och dynamisk maximal styrka i främre lårmuskulaturen av styrketräning? Är det någon skillnad i resultat mellan koncentrisk och excentrisk styrka i lårmuskulaturen före och efter styrketräningsperioden? Är det någon skillnad i förändring mellan benstyrka uppmätt med isokinetisk teknik jämfört med uthållighetsstyrka och ett kort funktionellt benstyrketest? Hur påverkas maximal syreupptagningsförmåga registrerad via submaximalt cykeltest respektive vid pyramidtestet av träningsperioden? Metod. I studien deltog 20 generellt ej påtagligt aktiva män och kvinnor i åldrarna 66-79 år. Av dessa var 11 individer slumpvis indelade i en styrketräningsgrupp och övriga nio utgjorde en inaktiv kontrollgrupp. Ett flertal olika fysiologiska tester, som bl.a. prövade testpersonernas styrka samt kondition, utfördes innan och efter träningsperioden. De deltagare som utgjorde träningsgruppen tränades i relativt tung styrketräning i åtta veckor. Resultat. Undersökningen resulterade i en signifikant ökad koncentrisk-, excentrisk- samt statisk momentan benstyrka för träningsgruppen efter de åtta veckorna med relativt tung styrketräning. Vidare kunde även utläsas för dem en signifikant förbättring av uthållighetsstyrka i benen (hastighet vid 50 uppresningar från stol, med 16,9 %) samt vid ett kort funktionellt test (5 uppresningar från stol, med 12,8 %). De träningsgenererade signifikanta ökningarna för träningsgruppen tyder inte på några stora procentuella skillnader mellan statisk (10,4 %) och dynamisk excentrisk (7,8 %) eller koncentrisk maximal styrka (9,5 %). Vid testerna cykelergometertest (kondition), effekt i 5-minuterspyramidtest (ett modifierat steptest) samt distans vid 6-minuters gångtest framkom inga signifikanta förbättringar för träningsgruppen. Ingen i kontrollgruppen visade en signifikant förbättring i någon av de nämnda testerna. Slutsats. Studien visar att interventioner, med åtta veckors intensiv styrketräning, tre gånger per vecka för äldre kvinnor och män, påtagligt kan förbättra resultaten vid styrkemätningar såväl momentant som uthållighetsmässigt och vid ett kort funktionellt test, medan tester av maximal syreupptagningsförmåga (VO2max) inte förbättras. Emellertid framkom i cykelergometertestet en tendens till förbättring för träningsgruppen.

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