The purpose of this study was to explore utility of handgrip strength measured by the hand-grip dynamometer for assessment of nutritional status in protein-calorie malnutrition. The first study included six subjects (all right-handed), who had grip strength measured daily for five days, then weekly for three weeks. Intra-individual variability was approximately 10%. No learning or training effect was observed. Change in leg position from feet on the floor to elevation of feet made no significant difference in grip-strength measurement. In Phase Two, 43 healthy adult subjects (three left-handed) prior to elective surgery, height was significantly related to handgrip strength (r = 0.82, p < 0.001). Males were stronger than females. After surgery, the non-dominant hand lost significant strength (2.68 kilograms) and recovered more quickly than the dominant hand. Multiple regression analyses provided predictive equations for pre-surgery left hand-grip strength using age, sex, and height (R² = 0.77); from age, sex, hand measured, and grip strength two days after surgery or three days after surgery (R² = 0.89 for each). Ten sequential grip-strength measurements analyzed by repeated measures analysis of variance with orthogonal comparisons showed a difference in measurements between hands as well as before and after surgery. The slope of the measurement line was more linear before and three days after surgery, but more quadratic in shape two days after surgery. The effects seen by type of surgery were inversion of the slope of right hand sequential measurements two days after knee surgery and before-surgery drop and increase from trial five to trial seven in left hand sequential measurements of knee and vaginal hysterectomy subjects. In a six-month-long case study, grip-strength measurements were followed in a seriously-ill 68-year-old patient hospitalized for surgical repair of hiatal hernia and mucous fistula who underwent several periods of nutritional depletion. Grip strength varied throughout the period (although not differently from healthy subjects), but did not directly parallel changes in serum albumin or prealbumin. The conclusion was that hand strength measured by the handgrip dynamometer did not change enough with fasting and surgery from normal day-to-day variability to be useful for nutritional assessment.

Resistance training is widely prescribed for rehabilitation of injuries and as a method to improve athletic performance. It is accepted that resistance training increases the maximal force production of whole muscle and it has been suggested that the velocity of shortening can increase as well. However, little is known about the effects of resistance training at the cellular level. Therefore, we investigated morphology, force production, velocity, and force-velocity-power relationships of single chemically skinned muscle fibers from chronically resistance trained humans, including cross sectional area (CSA), peak Ca²⁺ -activated force production (P₀), specific tension (P₀/CSA), unloaded shortening velocity (V₀), and isotonic contractions. The untrained group (NT) group consisted of sedentary males (n=6, age =27 ± 2 yrs) while the chronically trained group (CHRT) group consisted of males with 7.7 ± 0.4 yrs resistance training experience (n=6, 22 ± 1 yrs). Maximum voluntary isometric and isokinetic knee extensor strength were measured along with 6 repetition maximum (6RM) free weight bench press and leg press. Muscle biopsies were obtained from the vastus lateralis. Chemically skinned single muscle fibers were mounted between a force transducer and servo-controlled motor and subjected to slack tests to determine peak Ca²⁺ -activated force (P₀) and unloaded shortening velocity (V₀). Isotonic load clamps were used to determine the force-velocity-power relationship. All fiber experiments were performed at 15°C. Fiber myosin heavy chain (MHC) content was determined by gel electrophoresis. The CHRT group was 119% and 81% stronger for 6RM leg press and bench press respectively. Peak isometric torque was 28% greater for the CHRT subjects and was significantly higher at all isokinetic speeds tested. No differences were seen in strength or isokinetic power between groups after normalization for lean body mass. CHRT fibers (n=213) expressing type I, IIa, and I₀a/IIx MHC were significantly greater in CSA (+41%, +51%, and +33%, respectively) and produced significantly greater P₀ (+37%, +48%, and +34%, respectively) than NT fibers (n=236). However, P₀/CSA was not different between CHRT and NT groups. Fibers expressing type IIa/IIx fibers produced greater P₀/CSA than IIa which produced greater P₀/CSA than type I. The P₀/CSA relationship between fibers within groups was type IIa/IIx>IIa>I and was significant for both groups. Fiber V₀ was not different between groups. Absolute power was significantly greater in the CHRT for all fiber types whereas power normalized for fiber volume was not different between groups. This resulted in a significantly greater force at peak power for all but type IIa/IIx fibers and trends for greater velocity at peak power. Single-cell contractile function in terms of V₀ and P₀/CSA, measured under standardized conditions, appears to be unaltered as a result of long term CHRT in young adult males. Group differences in absolute P₀ can be attributed solely to the greater CSA of the CHRT fibers. Long-term CHRT is not associated with a difference in fiber V₀. Therefore, the greater power was due entirely to the greater force. These data suggest that differences in whole muscle strength and power between NT and CHRT groups are primarily due to differences in fiber CSA rather than differences in cross-bridge mechanisms of contraction. Supported by National Institute of Health grant R3AR46392A. / Graduation date: 2002

The purpose of this study was to determine the correlation among three hand strength measurement methods: Hand dynamometer, MDD (Middle Digital Extension Isokinetic Dynamometer), and Cybex. Five students (2 males, 3 females) from Ball State University were asked to participate in this study. Both right and left lower arm data were collected from these subjects. A Cybex 340 (Lumax Cor.) was employed to determine wrist flexion and extension isokinetic peak torque, total work, and power at 30 degrees/second and 60 degrees/second. A MDD was used to determine third digit eccentric torque, work, and power. A hand dynamometer (Lafayette Instrument Co., Model 76618) was used to determine grip force. Pearson product moment correlation coefficients were used to determine correlation among these variables. Significant correlations were noted between isometric grip strength and isokinetic 30 and 60 degrees/second wrist flexion power, as well as between isometric grip strength and isokinetic 30 degrees/second wrist extensor power. The results of this study indicate there is very little relationship between the three clinically used measurement tools. / School of Physical Education

Complex networks is an interdisciplinary research area which focuses on the study of properties of complex systems that have many functional or structural subunits. Community detection algorithms are one of the major approaches to analyse complex networks with multilevel or overlapping community structures. This research work focuses on constructing a novel community detection approach for simplification of a given complex demographic network. The general process of the abstraction from concrete problems as well as the general definition of communities have not been well defined and all the existing methods are derived from specific backgrounds, leaving the reliabilities in other fields open to ques- tion. This specificity of the existing methods reveals the need for a general approach for community definition and detection. Here, we devise a general procedure to find community structures in concrete problems by classifying the concrete networks into two basic types: Transmission networks and Similarity networks. The relation among nodes in transmission networks are constructed by material transmission and the ones in similarity network are constructed by the similarity in properties of the nodes. We show that both the types can be represented based upon an unified graph model. Based on the model, we propose a generic approach, Relation Strength Measurement (RSM), to define the communities. We have demonstrated that the Effective Resistance Function (ERF), from the Klein and Randic’s electrical network model, is applicable for quantifying the relation among nodes. We have also introduced a community threshold parameter (CP) based on which, the RSM algorithm categorizes the network nodes into communities. We have compared the performance of our algorithm with other well known community detection methods. The simulation results show that the algorithm accurately obtains the division of community structure both in real-world and synthetic networks.

Fourteen college softball players were recruited to participate in this study to determine if a strength imbalance between the lower extremities, how significant this difference this may be and of any correlations existed among all the functional tests. Subjects took part in isokinetic flexion and extension at 60 and 240 deg/sec, parallel squats, 2-legged vertical jump, single leg vertical jump, and a five-hop test. Peak and average torque was recorded for isokinetic testing and revealed significant differences between the dominant and non-dominant limbs (13.00%- 16.00%). Peak and average force was analyzed for squats and all vertical jumps. Significance was found among all activities between dominant and non-dominant legs, other than average force for single leg vertical jump. A significant difference was also exhibited for the five-hop test between the lower extremities. Significant correlations were also found at the 0.05 and 0.01 levels amongst the various functional tests. Overall findings revealed a significant strength imbalance between the dominant and non-dominant limbs. Further research needs to be conducted in determining how detrimental these differences could be in daily performance for athletes. / School of Physical Education

Background: There is lack of measurement methods to evaluate postoperative rehabilitation for people who have undergone orthopedic surgery of the foot at Uppsala University Hospital. One objective method is to measure muscle strength with MicroFET2, which is available at the hospital. Before implementing the method it is necessary to ensure the the reliability of supination and pronation measured with MicroFET2 because there are no studies that have explored this. Pronators and supinators are important muscles for the stability of the foot and to the arch of the foot. Objective: To examine intra-rater reliability of peak strength of pronation and supination of left and right foot using handheld dynamometer (MicroFET2) in adults without leg- or footpain. Methods: The intra-rater reliability was evaluated in 24 adults by test-retest with 7 days between measures. The test were supination and pronation of the left and right foot. Interclass correlation coefficient (ICC 2,1) and standard error of measurement (SEM and SEM%) were calculated. Results: The results from this study showed high intra-rater reliability for both supination and pronation with ICC between 0.73-0.88 for mean of three trials and 0.74-0.89 for highest value of three trials. SEM och SEM% varied between 14.5-24.4 N and 7.7-11.9% at mean of three trials and 14.1-25.6 N and 7.2-11.9% at highest value of three trials. Conclusion: MicroFET2 is a reliable instrument to measure strength in the foot supinator and pronator-muscles in healthy adults. / Bakgrund: Vid Akademiska sjukhuset i Uppsala saknas det ett objektivt sätt att mäta maximal muskelstyrka vid rehabilitering efter fotoperation. En objektiv mätmetod för maximal muskelstyrka är dynamometern MicroFET2 som finns på sjukhuset. För att implementera denna metod behövs säkerställande av reliabiliteten för pro- och supination mätt med MicroFET2 eftersom det saknas studier som undersöker detta. Pronatorer och supinatorer är viktiga muskelgrupper för fotens stabilitet och fotvalv. Syfte: Undersöka intrabedömarreliabilitet vid maximal isometrisk muskelstyrka av höger och vänster fots supinatorer och pronatorer med handhållen dynamometer (MicroFET2) hos vuxna individer utan ben- eller fotsmärta. Metod: Intrabedömarreliabiliteten undersöktes genom test-retestförfarande med 7 dagars intervall på 24 personer. Muskelgrupper som mättes var fotens supinatorer och pronatorer på både höger och vänster fot. Interclass correlation coefficient (ICC 2,1) samt standard error of measurement (SEM och SEM%) beräknades. Resultat: Resultatet från studien visar på hög relativ intrabedömarreliabilitet i både supination och pronation med ICC mellan 0.73-0.88 vid medelvärde av tre försök och mellan 0.74-0.89 vid högsta värde av tre försök. SEM och SEM% varierade mellan 14.5-24.4 N och 7.7-11.9% vid medelvärde av tre försök respektive mellan 14.1-25.6 N och 7.2-11.9% vid högsta värde av tre försök. Slutsats: MicroFET2 är ett reliabelt instrument för att mäta styrka i fotens pronatorer och supinatorer på friska vuxna personer.

Thesis (MScMedSc (Biomedical Sciences))--University of Stellenbosch, 2005. / The purpose of this study was to determine the physiological and kinanthropometric attributes, respiratory muscle strength, and core stability of successful endurance paddlers, and to investigate the associations of these characteristics with kayak endurance performance in the laboratory and the field. Twenty male competitive paddlers (age: 28 ± SD 7 years, height: 184 ± SD 7 cm and weight: 80 ± SD 7 kg) were categorised in two ability groups, Elite and Sub-Elite. Testing included kinanthropometric measurements, maximum aerobic capacity, pulmonary function, six core stability tests, a 30 min endurance performance test (EPT) on the K1 Ergo and a 10 km time trial (TT) on the water. Maximum inspiratory mouth pressure (MIP) was measured before and after the 30 min EPT on the K1 Ergo to assess respiratory muscle fatigue. The Elite paddlers demonstrated significantly greater values for sitting height (as a percentage of stature), relative VO2max, PPO, PPO/kg, MVV and MIP compared to the Sub-Elite paddlers (All P < 0.05). They also demonstrated a significantly greater average PO and average back stroke length during the 30 min K1 Ergo EPT (P < 0.05) and a significantly faster race time (44:10 ± 1:17 vs 47:34 ± 3:14 min:s) during the 10 km water TT (P < 0.05), compared to the Sub-Elite paddlers. The paddlers did not experience respiratory muscle fatigue (as determined by change in MIP) after the 30 min K1 Ergo EPT. Significant intraclass correlations coefficients of r = 0.81 for average PO (30 min K1 Ergo EPT), r = 0.76 for MIP, and r = 0.95 for 10 km performance time, revealed the high repeatability of these tests. Significant relationships were found between the two endurance performance tests (30 min K1 Ergo EPT and 10 km water TT, r = -0.64, P < 0.05) and between both tests and a number of kinanthropometric, physiological and respiratory muscle function parameters. Stepwise multiple regression analysis revealed that PPO and MVV predicted endurance performance (average PO) on the K1 Ergo (R2 = 0.75, SEE = 15 W), whereas relative VO2max and best MIP predicted 10 km performance time on the water (R2 = 0.64, SEE = 115 s). The results of this study suggest that superior maximum aerobic capacities and respiratory muscle function distinguish successful paddlers from less successful paddlers and may be used to predict kayak endurance performance in the laboratory as well as on the water. No respiratory muscle fatigue occurred during the 30 min K1 Ergo EPT, indicating that respiratory muscle fatigue may not be a limiting factor to 30 min kayak endurance performance. The core stability results demonstrated no relevance to kayak endurance performance.

This study was to clarify strength factors using 12 selected exercises on the Universal Gym, and to determine what measures present a valid method of assessing strength of college-aged males, Eighty-eight males enrolled in beginning weight-training classes used the Universal Gym for twelve weeks, Subjects were tested for maximum strength on 12 exercises, Alpha and canonical factor analyses were performed on raw scores of all measures, and on scores when body weight and standing height variances were removed. A three-factor structure of upper extremity, lower extremity, and trunk strength was revealed when weight, and weight and height combined were statistically controlled. Results showed that residualized scores of weight can be used to evaluate strength on the Universal.Gym,

The purpose of the present study was to investigate if any relationship exists between anthropometric measurements with average concentric velocity (ACV) at various intensities in the back squat and the number of repetitions able to be performed during a set to volitional fatigue at 70% of one-repetition maximum (1RM). It was hypothesised that short femurs and total height would be related to slower ACVs and lower total number of repetitions performed. 58 resistance trained subjects were recruited and attended one day of data collection. Subjects performed 1RM testing of the back squat followed by two single repetition sets at 30-90% of 1RM and a 70% of 1RM set to fatigue. There was no significant correlation between femur length and height with ACV at any intensity (p>0.05). A significant negative correlation existed between both height (r=-0.39, p=0.003) and femur length (r=-0.31, p=0.018) with total number of repetitions performed. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection

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