SEARCH · PubMed Health

Results for “Strength”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

PubMed2003

The influence of resin coating on the shear punch strength of a high strength auto-cure glass ionomer.

OBJECTIVES: The aim of this study is to examine the influence of early water contact on the shear punch strength of a modern, high strength, auto-cure glass ionomer (Fuji IX GP). METHODS: Specimens, 8.0mm in diameter and approximately 1.25mm thick, were prepared in metal washers, and allowed to remain covered by polyester strips for 7min, to ensure completion of the initial set. A minimum of 32 specimens was prepared for each set of experiments and they were divided into two equal groups. Following removal of the strips, the surfaces of the specimens in Group 1 were immediately coated on both sides with Fuji Coat LC and light cured for 10s. In Group 2 the specimens were left uncoated. All specimens were then placed in distilled water at 37 degrees C, and stored for periods of 24h, 1, 2, 5, or 8 weeks. The strength of the specimens was measured at each time interval in the shear mode by a punch test in a universal testing machine. RESULTS: The mean strength of the coated specimens in Group 1, which had been protected against exposure to water, increased significantly on ageing from 67.1 (24h) to 78.0MPa (1 week), with no further significant change in strength. The mean strength of the specimens in Group 2 increased significantly from 75.7 (24h) to 83.3 (1 week) and 91.9MPa (2 weeks), with no further significant change in strength. Uncoated specimens were stronger at all points of time. The difference was statistically significant at 24h, 2, 5, and 8 weeks (P<0.05), but not at 1 week (P=0.061). Significance. The results suggest that, contrary to the usual instructions for placement of glass ionomer, early access to water will positively influence the shear punch strength of Fuji IX GP.

Analysis of Variance↗

PubMed1997

Measurement of thumb abduction strength: normative data and a comparison with grip and pinch strength.

Abduction strength of the thumb was measured in normal men (n = 101; age range, 21-94 years) and women (n = 208; age range, 20-97 years). Abduction-strength measurements were conducted concurrently with grip and pinch strength measurements made by well-established clinical methods. Normal values were established and stratified by age and sex. Thumb abduction strength generally correlated with grip and pinch strength. All strength variables at all ages were greater in men than in women. The magnitude of all strength variables was maintained from 20 to 59 years of age, then decreased with increasing age in both men and women. Measurement of thumb abduction strength may prove to be a useful adjunct to the various tests currently used by hand surgeons to assess hand function.

Adult↗

PubMed1992

A comparison of strength and muscle endurance in strength-trained and untrained women.

Muscular strength and fatigability of strength-trained (ST) and untrained (UT) women were compared during a 6-min bout of maximal rhythmic exercise involving the elbow flexor muscles given at a rate of 30 contractions.min-1. Fifteen ST and 15 UT subjects, aged 18-34 years and pair-matched for body size, were tested for differences in initial strength, final strength, absolute endurance, relative endurance, and rate of fatigue. Results revealed a significant difference in initial strength, final strength, and absolute endurance in favor of ST subjects. No significant difference was found for relative endurance, and rates of fatigue were similar for both groups. It is concluded that muscular strength and endurance are enhanced in women engaged in a training program designed primarily to increase muscular strength and hypertrophy, but fatigability is not affected.

Adolescent↗

PubMed1996

Local bone mineral density, muscle strength, and exercise in adolescent boys: a comparative study of two groups with different muscle strength and exercise levels.

The primary objective of the present study was to evaluate the impact of physical activity and muscle strength on bone mineral density (BMD) of the tuberositas tibiae in adolescent boys. Two groups with different exercise levels were compared. The high activity group consisted of 20 subjects (age 15.9 +/- 0.3) from a junior ice hockey team. The reference group consisted of 24 volunteers (age 15.9 +/- 0.3) not training for more than 3 hours per week. The groups were matched for age, weight, and pubertal stage. BMDs (g/cm2) of the tuberositas tibiae and proximal tibia were measured using dual energy X-ray absorptiometry. Quadriceps strength was significantly higher in the high activity group (P < 0.01). Univariate correlations were measured between tuberositas tibiae BMD and pubertal stage, weight, height, BMI, fat mass, lean body mass, quadriceps strength, and hamstrings strength in the high activity group and the reference group, respectively. Quadriceps strength was estimated to be the best significant predictor of BMD of the tuberositas tibiae in the reference group. A multivariate analysis confirmed this result. In the high activity group, there was no significant predictor of BMD of the tuberositas tibiae. There was no significant difference in BMD at this site when comparing the two groups. However, five of the boys in the high activity group had a former history of Mb Osgood-Schlatter with a significantly lower BMD of the tuberositas tibiae than the rest of the boys in that group. After exclusion of these boys, the remaining 15 boys were matched against 20 boys from the reference group using the previous criteria. These 15 boys then showed a significantly higher BMD of the tuberositas tibiae (P < 0.05) but not of the proximal tibia than the 20 boys in the reference group. In conclusion, this study demonstrates site-specific increments of tuberositas tibiae BMD in adolescent ice hockey players unless they are affected by the negative effects on BMD by Mb Osgood-Schlatter. These increments seem primarily to be associated with forceful muscle contractions related to high quadriceps strength and not greater weight-bearing loading. Muscle strength seems to positively affect BMD of the tuberositas tibiae in adolescents, but only up to a certain level, above which additional muscle strength has no effect.

Adolescent↗

PubMed2003

Creatine supplementation enhances isometric strength and body composition improvements following strength exercise training in older adults.

We sought to determine whether creatine monohydrate (CrM) supplementation would enhance the increases in strength and fat-free mass that develop during resistance exercise training in older adults. Twenty-eight healthy men and women over the age of 65 years participated in a whole-body resistance exercise program 3 days per week for 14 weeks. The study participants were randomly allocated, in a double-blind fashion, to receive either CrM (5 g/d + 2 g of dextrose; n = 14) or placebo (7 g of dextrose; n = 14). The primary outcome measurements included the following: total body mass, fat-free mass, one-repetition maximum strength for each body part, isometric knee extension, handgrip, and dorsiflexion strength, chair stand performance, 30-m walk test, 14-stair climb performance, muscle fiber type and area, and intramuscular total creatine. Fourteen weeks of resistance exercise training resulted in significant increases in all measurements of strength and functional tasks and muscle fiber area for both groups (p <.05). CrM supplementation resulted in significantly greater increases in fat-free mass and total body mass, as compared with placebo (p <.05). The CrM group also showed a greater increase in isometric knee extension strength in men and women, as compared with placebo (p <.05), and also greater gains in isometric dorsiflexion strength (p <.05), but in men only. There was a significant increase in intramuscular total creatine in the CrM group (p <.05). Finally, there were no significant side effects of treatment or exercise training. This study confirms that supervised heavy resistance exercise training can safely increase muscle strength and functional capacity in older adults. The addition of CrM supplementation to the exercise stimulus enhanced the increase in total and fat-free mass, and gains in several indices of isometric muscle strength.

Age Factors↗

PubMed2001

Strengths-based case management: individuals' perspectives on strengths and the case manager relationship.

Strengths-based practice in social work has a strong theoretical foundation as an effective helping strategy that builds on a person's successes. Although there is growing empirical evidence informing outcomes associated with strengths-based approaches, missing from the literature is an understanding of how individuals who receive these services view their experiences. Qualitative data collection methods were used to gather individuals' experiences of participating in strengths-based case management implemented in a substance abuse aftercare program. The research questions that guided the study were "What are individuals' perceptions of strengths-based case management?" and "How do those perceptions compare and contrast to the key principles of strengths-based case management?" The emerging themes centered on individuals' responses to a focus on strengths (acceptance of strengths; holding on to strengths and deficits simultaneously; and initial mistrust of the approach) and to the relationship with the case manager (acceptance of the relationship; guilt when success is not achieved; and not needing the relationship). Implications for social work practice are discussed.

Adaptation, Psychological↗

PubMed2003

Effect of strength and proprioception training on eversion to inversion strength ratios in subjects with unilateral functional ankle instability.

OBJECTIVES: To examine the effect of six weeks of strength and proprioception training on eversion to inversion isokinetic strength ratios (E/I ratios) in subjects with unilateral functional ankle instability. METHODS: Thirty eight subjects were randomly assigned to one of four treatment groups: strength training (S); proprioception training (P); strength + proprioception training (B); control (C). Isokinetic strength was tested before and after training using a Kin Com 125 automatic positioning isokinetic dynamometer. Subtalar joint eversion and inversion motions were tested both concentrically and eccentrically through a range of motion involving 40 degrees. All peak torque and average torque values were normalised for body mass. E/I ratios were calculated from average torque and peak torque measures by taking the concentric eversion value and combining it with the eccentric inversion value. Data were analysed using a mixed model analysis of variance with repeated measures on the test factor. Average torque and peak torque E/I ratios at 30 and 120 degrees/s were analysed separately. RESULTS: There were no significant differences in average torque and peak torque E/I ratios of the functionally unstable ankle for any of the groups after training compared with before. CONCLUSIONS: Six weeks of strength and proprioception training (either alone or combined) had no effect on isokinetic measures of strength in subjects with self reported unilateral functional instability. Further studies examining this agonist (concentric) to antagonist (eccentric) muscle group strength ratio are needed.

Adult↗

PubMed2003

[Sarcopenia and strength training. Age-related changes: effect of strength training].

Sarcopenia signifies the age-related loss of muscle mass and consequently muscle strength. Sarcopenia appears to be caused by both muscular and neural factors. Concurrently with the muscle atrophy, a non-linear loss of muscle strength is observed. The decline accelerates after the age of 60. The ability to produce muscular power is reduced even more than the muscle strength. Strength training increases muscle strength and muscular power in the elderly thus counteracting part of the age-related reduction. Improvements, however, depend on the initial strength in the elderly person. The benefit of strength training is greatest in frail elderly and the oldest old, although elderly in general could benefit from strength training. Considering the growing section of elderly in the population, the focus on sarcopenia and measures to counteract this seems more relevant than ever.

Aged↗

PubMed1990

[Strength of teeth to fracture by impact. Testing of fractural strength against impact force, using replication models of human permanent teeth].

Traumatic injury anterior teeth is often encountered clinically. A number of clinical and statistical studies have so far been undertaken for the incidences, causes and ages in terms of the site of fracture. However, little has been attempted at fundamental estimation of the fractural resistance of anterior teeth that are susceptible to fracture. This has been studied in only an erect position of eruption by Nose or Chin. Changes in resistance of teeth in a twisted position or at different angles of eruption still remain unstudied. We took an interest in the relation between physicopositional conditions of human teeth and changes in their fractural strength against impact. Determination of the resistance of teeth to a variety of experimental conditions was attempted by use of an Izod-type tester. Epoxy resin replication models of human anterior teeth were used as experimental specimens, since human teeth were considered inappropriate because of their large individual differences and an anticipated difficulty in precise reproduction of the angles of eruption and torsion. The following results were obtained; (1) In the replication models of teeth erected positioned at 90 degrees vertically to the horizontal plane, the fractural strength against impact was highest for the maxillary cuspid model and was lowest for the mandibular central incisor model. (2) In the replication models of teeth with their mesial or distal incisal margin twisted 45 degrees medially, the fractural strength was reduced for all the teeth except the maxillary central incisors. (3) In comparison of the strength between the replication models with the mesial incisal margin twisted 45 degrees medially and those with the distal incisal margin twisted likewise am marked reduction in strength was found for the maxillary cuspid model prepared in the former condition of torsion. For the mandibular cuspid model, a relatively large reduction of the strength was found in the latter condition of torsion. (4) In comparison of the strength of teeth positioned at various angles, the strength was decreased by slanting either labially or lingually for all the replication models except the maxillary and mandibular cuspid models.

Cuspid↗

PubMed2000

Isometric pull and push strengths of paraplegics in the workspace: 1. Strength measurement profiles.

The isometric strength profiles of male and female paraplegics were determined for pull and push strengths in the normal, maximum, and extreme working reach envelopes. A computerized isometric strength measurement system was designed and constructed for the purpose. The strongest pull location was at extreme reach vertically above the shoulder and the strength values for males and females were 473 and 318 newtons (N), respectively. The strongest push location was at maximum reach, at vertical (phi) angle of 45 degrees and at horizontal (theta) angle of 45 degrees for males and at 0 degrees for women and the strength values were 235 and 172 N, respectively. The nature of the strength profiles was found to be similar for both the sexes. The pull and push strengths of the female were 77 and 68% that of the male, respectively.

Adult↗

PubMed1980

Interference of strength development by simultaneously training for strength and endurance.

The purpose of this study was to determine how individuals adapt to a combination of strength and endurance training as compared to the adaptations produced by either strength or endurance training separately. There were three exercise groups: a strength group (S) that exercised 30--40 min . day-1, 5 days . week-1, and endurance group (E) that exercised 40 min . day-1, 6 days . week-1; and an S and E group that performed the same daily exercise regimens as the S and E groups. After 10 weeks of training, VO2max increased approx. 25% when measured during bicycle exercise and 20% when measured during treadmill exercise in both E, and S and E groups. No increase in VO2max was observed in the S group. There was a consistent rate of development of leg-strength by the S group throughout the training, whereas the E group did not show any appreciable gains in strength. The rate of strength improvement by the S and E group was similar to the S group for the first 7 weeks of training, but subsequently leveled off and declined during the 9th and 10th weeks. These findings demonstrate that simultaneously training for S and E will result in a reduced capacity to develop strength, but will not affect the magnitude of increase in VO2max.

Adaptation, Physiological↗

PubMed1986

Bone strength measurements at the proximal tibia. Penetration tests and epiphyseal compressive strength.

Three penetration tests were obtained from corresponding locations at each condyle of 19 proximal tibiae. The patterns of condylar cancellous bone strength varied little between knees. The medial condyle was the strongest with an average medial to lateral strength ratio of 1.9, and in most knees the medial condyle was strongest centrally while the lateral condyle was strongest posteriorly. The penetration strength at 5 successive 2 mm levels beneath the resected subchondral surface also showed a constant pattern of variation. Bone strength decreased significantly at first except at the posterolateral site, then tended to level off. The reduction of strength was most pronounced in the centre of the condyles. The penetration tests were good predictors of the static compressive strength of the proximal tibia. Correlation coefficients of approximately 0.90 were obtained indicating statistically highly significant correlations (p less than or equal to 0.00001). The tests were carried out with equipment developed for in vivo measurements of cancellous bone strength during total knee replacement. The findings confirm the close relationship of these investigations to conventional compression tests.

Aged↗

PubMed1994

Generality versus specificity: a comparison of dynamic and isometric measures of strength and speed-strength.

Considerable debate exists as to whether the qualities of muscle function exist as general or specific physiological capacities. If there is a generality of muscle function then strong relationships would exist between various measures of function for the same muscle(s), independent of the test contraction, mode or velocity. The purpose of this study was to examine the relationship between isometric and dynamic measures of muscle function to determine the existence of generality or specificity. A group of 22 men, experienced in weight training, were tested for lower and upper body dynamic and isometric measures of strength and speed-strength. The changes in these measures consequent to a resistance training programme were also investigated. The results of this study indicated that whilst isometric and dynamic measures of strength did significantly correlate (r = 0.57-0.61), the relationship was below that required to denote statistical generality. More important, the changes in isometric and dynamic strength consequent to a dynamic heavy resistance training programme were unrelated (r = 0.12-0.15). Thus the mechanisms that contribute to enhanced dynamic strength appeared unrelated to the mechanisms that contribute to enhanced isometric strength. Measures of dynamic and isometric speed-strength were unrelated, as were the changes in these measures resulting from training. The results of this study demonstrated that a generality of muscle function did not exist and that modality specific results were observed. Consequently this study calls into question the validity of isometric tests to monitor dynamically induced training adaptations.

Adult↗

PubMed2002

Isometric strength measurement for muscle weakness in cancer patients: reproducibility of isometric muscle strength measurements with a hand-held pull-gauge dynamometer in cancer patients.

Our aim was to determine several indexes of reproducibility for strength measurements with a hand-held pull-gauge dynamometer (MFB50K) in cancer patients. Two independent testers performed repeated measurements of maximal isometric elbow and knee strength. The measurements were gathered in a convenience sample of 40 patients (27 men, age 20-72 years) with various types and stages of cancer. These patients were recruited from the medical oncology clinic of a university hospital. The Pearson product moment correlation coefficient, the intraclass correlation coefficient (ICC), the standard error of measurement (SEM) and its associated 95% confidence interval, the smallest detectable difference (SDD) and the limits of agreement were determined as outcome measures for reproducibility. The results for the Pearson product moment correlation and the ICC were 0.90 for elbow and 0.96 for knee extension strength. The results in terms of the SDDs were 29.4 newton (N) for elbow and 54.8 N for knee strength. The limits of agreement for elbow strength were -21.7 N and 38.5 N (mean 8.4 N). For knee strength the limits of agreement were -49.8 N and 59.8 N (mean 5 N). The Pearson product moment correlation and the ICC suggested good reproducibility. However, the more informative indices of reproducibility, i.e. the SEM and the SDD, showed relatively large measurement error between the testers. Therefore, the current use of the MFB50K for the measurement of muscle strength is not supported in cancer patients.

Adult↗

PubMed2006

Combinatory effects of high-intensity-strength training and sensorimotor training on muscle strength.

It has been shown in classical strength training studies using high loads that improvements in rate of force development are mainly due to adaptations in the intramuscular coordination. Adaptations following sensorimotor training were also characterized by improvements in the rate of force development during maximum voluntary isometric contraction. The purpose of the present study was to investigate neuromuscular adaptations of combined sensorimotor and classical strength training. Eighteen subjects were randomly assigned to two groups. Group 1 (SMT-HST) had to perform a period of sensorimotor training at first and a high-intensity strength training afterwards. Group 2 (HST-SMT) performed the high intensity strength training at first and the sensorimotor training after. Maximum voluntary isometric contraction and neuromuscular activation were measured at three occasions: Before training, after the first, and after the second period. The results after the first period confirmed the positive effects of both training regimen on rate of force development (13 % [SMT-HST] and 27 % [HST-SMT], p < 0.05) and on maximum strength (9 % [HST-SMT] and 12 % [SMT-HST], p < 0.05) during maximum voluntary contraction. Improvements caused by sensorimotor training could only be achieved, when it was performed at first. It is supposed that classical strength training with high loads basically improves the mechanical efficiency of the effectors, whereas sensorimotor training alters the afferent input on the central nervous system. In combination, the sensorimotor training can have preconditioning effects on the strength training. A combination of both training methods can thus be recommended, if the sensorimotor training is performed at first.

Adaptation, Physiological↗

PubMedDate not supplied

Muscle hypertrophy, strength development, and serum hormones during strength training in elderly women with fibromyalgia.

OBJECTIVE: To examine the effects of strength training on maximal force, cross-sectional area (CSA), and electromyographic (EMG) activity of muscles and serum hormone concentrations in elderly females with fibromyalgia (FM). METHODS: Twenty-six patients with FM were randomly assigned to a training (FMT; n = 13; mean age 60 years) or a control (FMC; n = 13; 59 years) group. FMT performed progressive strength training twice a week for 21 weeks. The measurements included maximal isometric and concentric leg extension forces, EMG activity of the vastus lateralis and medialis, CSA of the quadriceps femoris, and serum concentrations of testosterone (T), free testosterone (FT), growth hormone (GH), insulin-like growth factor-1 (IGF-1), dehydroepiandrosterone sulfate (DHEAS), and cortisol. Subjectively perceived symptoms of FM were also assessed. RESULTS: All patients were able to complete the training. In FMT strength training led to increases of 36% (p<0.001) and 33% (p<0.001) in maximal isometric and concentric forces, respectively. The CSA increased by 5% (p<0.001) and the EMG activity in isometric action by 47% (p<0.001) and in concentric action by 57% (p<0.001). Basal serum hormone concentrations remained unaltered during strength training. The subjective perceived symptoms showed a minor decreasing tendency (ns). No statistically significant changes occurred in any of these parameters in FMC. CONCLUSION: Progressive strength training increases strength, CSA, and voluntary activation of the trained muscles in elderly women with FM, while the measured basal serum hormone concentrations remain unaltered. Strength training benefits the overall physical fitness of the patients without adverse effects or any exacerbation of symptoms and should be included in the rehabilitation programmes of elderly patients with FM.

Aged↗

PubMed2005

Strength training and detraining effects on muscular strength, anaerobic power, and mobility of inactive older men are intensity dependent.

BACKGROUND: Although strength training (ST) enhances physical function in the elderly, little is known about the effect of training intensity on training and detraining adaptations in musculoskeletal fitness. OBJECTIVE: To determine the effect of exercise intensity on strength, anaerobic power, and mobility of older men subjected to a 24 week ST protocol followed by prolonged detraining. METHODS: Fifty two healthy but inactive older men (mean (SD) age 71.2 (4.1) years) were assigned to a control (n = 14), low intensity training (LIST; n = 18; 55% 1RM), or high intensity training (HIST; n = 20; 82% 1RM) group. They carried out a 24 week, whole body (10 exercises, two to three sets/exercise) ST programme followed by a 48 week detraining period. Upper and lower body strength, anaerobic power (Wingate testing), and mobility (timed up and go, walking, climbing stairs) were measured at baseline and immediately after training and during detraining. RESULTS: Although low intensity training improved (p<0.05) strength (42-66%), anaerobic power (10%), and mobility (5-7%), high intensity training elicited greater (p<0.05) gains (63-91% in strength, 17-25% in anaerobic power, 9-14% in mobility). All training induced gains in the LIST group had been abolished after four to eight months of detraining, whereas in the HIST group strength and mobility gains were maintained throughout detraining. However, anaerobic power had returned to baseline levels after four months of detraining in both groups. CONCLUSIONS: Higher intensity training protocols induce greater gains in strength, anaerobic power, and whole body physical function of older men. Moreover, higher intensity training may maintain the gains for more prolonged periods after training ceases.

Aged↗

PubMedDate not supplied

Development of lower leg strength and flexibility with the strength shoe.

The Strength Shoe is a modified athletic shoe with a 4-cm thick rubber platform attached to the front half of the sole. It is promoted as an effective method of increasing "speed, quickness, and explosive power," as well as ankle flexibility and calf circumference, when used in a plyometrics-based training regimen. This study evaluates, in a prospective, randomized trial, the efficacy and safety of the Strength Shoe training regimen for increasing lower leg flexibility and strength in intercollegiate track and field participants. No enhancement of flexibility, strength, or performance was observed for participants wearing the Strength Shoe at the end of an 8-week training program, following the suggested regimen of the manufacturer. The use of the Strength Shoe cannot be recommended as a safe, effective training method for development of lower leg strength and flexibility. However, the use of plyometrics in a properly supervised setting may improve athletic performance and merits further investigation.

Evaluation Studies as Topic↗