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21.

Objective

This study aimed to determine the inter-rater and intrarater reliability, agreement, and minimal detectable change (MDC) of the neck muscle strength test using a handheld dynamometer in healthy women and women with headaches.

Methods

Neck muscle strength in maximal voluntary contraction was measured using the Lafayette Manual Muscle Testing attached to a nonelastic belt in 25 women with migraines and in 25 healthy women. Three repetitions of flexion, extension, and lateral flexion were performed. The tests were performed by 2 examiners on the same day, with a 10-minute interval, and by 1 examiner, with a 1-week interval. The reliability was verified by the intraclass correlation coefficient, the agreement determined by standard error measurement, and the MDC calculated.

Results

The protocol exhibited moderate to excellent intrarater and inter-rater reliabilities in both groups (intraclass correlation coefficientrange, 0.53-0.90). The standard error measurement ranged from 0.43 to 1.81 and the MDC from 1.49 up to 4.61.

Conclusion

Quantification of neck muscle strength using the handheld dynamometer with an attached nonelastic belt exhibited moderate to excellent intra- and inter-rater reliability in women with and without migraines. Moreover, the standard error measurement and MDC were proven to be useful in the interpretation of data and in guiding clinical decisions.  相似文献   
22.
目的 观察Thera-Band渐进抗阻肌力训练对脑卒中后患者下肢运动功能及步态的影响。 方法 将脑卒中后偏瘫患者48例按随机数字表法分为治疗组(24例)和对照组(24例)。对照组采用常规康复治疗,治疗组在常规康复治疗基础上增加Thera-Band弹力带对偏瘫侧肌肉进行渐进抗阻训练。分别于治疗前和治疗8周后(治疗后)采用Fugl-Meyer运动功能评定量表(FMA)、Berg平衡量表(BBS)、功能独立性评定量表(FIM)中的行走和上下楼梯功能检测标准以及GaitWatch步态分析对2组患者进行评定。 结果 治疗后,治疗组的FMA评分[(24.54±2.47)分]、Berg评分[(39.21±2.25)分]、FIM评分[(12.46±1.06)分]、步频[(79.00±8.08)steps/min]、步幅[(59.75±3.31)cm]、步速[(40.29±5.04)cm/s]以及对照组的FMA评分[(20.67±2.65)分]、Berg评分[(28.92±2.90)分]、FIM评分[(11.92±0.97)分]、步频[(69.17±8.11)steps/min]、步幅[(56.38±3.46)cm]、步速[(36.08±4.84)cm/s]与组内治疗前比较,均有显著改善,差异均有统计学意义(P<0.05),且治疗组患者的FMA评分、Berg评分以及GaitWhatch步频、步幅、步速与对照组治疗后比较,差异均有统计学意义(P<0.05)。 结论 Thera-Band弹力带渐进抗阻训练结合常规康复训练可有效地改善脑卒中患者运动和步行能力。  相似文献   
23.
Summary The intra-session and inter-session reproducibility of knee extensor and flexor strength measurements were examined in 21 gonarthrotic subjects (ten women and eleven men). Using the Cybex 6000 dynamometer, isokinetic peak torque and total work at 30 and 120 degrees/second and isometric peak torque were measured three times on separate days within two weeks by the same examiner. The reproducibility of walking and stair climbing time measurements was also assessed. The concept of critical difference (i.e. the difference between two measurements which would be statistically significant when applied to a reference group in steady state) for the interpretation of muscle strength data obtained by monitoring individual patients is presented.Individual coefficients of variation (CV) were calculated for each muscle strength variable. Depending on the velocity and on whether peak torque or total work were measured, the median CV of intra-session and inter-session extensor strength measurements ranged from 1.5–4.9% and 7.4–10.1%, respectively. CVs for flexor strength measurements were significantly higher. Substantial variability of within subject variances were found, e.g. the 80% central range of CVs for extensor toruqe at 30 degrees/second was 2.5–29.5% (inter-session). Calculated from CVs, critical differences for inter-session measurements exceeded 30% for all muscle strength variables. Median CVs for walking and stair-climbing time were 7.0% and 4.9%, respectively.In conclusion, the large CVs and corresponding critical differences may be a major limitation in the use of muscle strength measurements in the individual gonarthrotic patient.  相似文献   
24.
The activation of competing intracellular pathways has been proposed to explain the reduced training adaptations after concurrent strength and endurance exercises (CE). The present study investigated the acute effects of CE, strength exercises (SE), and endurance exercises (EE) on phosphorylated/total ratios of selected AMPK and Akt/mTOR/p70S6K1 pathway proteins in rats. Six animals per exercise group were killed immediately (0 h) and 2 h after each exercise mode. In addition, 6 animals in a non-exercised condition (NE) were killed on the same day and under the same conditions. The levels of AMPK, phospho-Thr172AMPK (p-AMPK), Akt, phospho-Ser473Akt (p-Akt), p70S6K1, phospho-Thr389-p70S6K1 (p-p70S6K1), mTOR, phospho-Ser2448mTOR (p-mTOR), and phospho-Thr1462-TSC2 (p-TSC2) expression were evaluated by immunoblotting in total plantaris muscle extracts. The only significant difference detected was an increase (i.e., 87%) in Akt phosphorylated/total ratio in the CE group 2 h after exercise compared to the NE group (P = 0.002). There were no changes in AMPK, TSC2, mTOR, or p70S6K1 ratios when the exercise modes were compared to the NE condition (P ≥ 0.05). In conclusion, our data suggest that low-intensity and low-volume CE might not blunt the training-induced adaptations, since it did not activate competing intracellular pathways in an acute bout of strength and endurance exercises in rat skeletal muscle.  相似文献   
25.
This study extends the use of two lathyrogens, β-aminopropionitrile (BAPN) and D-penicillamine (DPA) from daily systemic or local-topical administration to long-time acting agents. This was achieved by converting the hydrophilic drugs into lipophilic derivatives. The synthesis of functional derivatives of DPA consisted in esterification with methyl-, hexyl-, or benzyl alcohols in the presence of thionylchloride. The esters formed were hydrochlorides, acidic and soluble in water. During neutralization in vitro or in vivo by tissue fluid, an oily substance is formed that elutes from a hydrogel polymer at a much slower rate than hydroplilic DPA itself. The degree of lipophilicity, measured as a partition coefficient between octanol/water, was highest for hexyl ester and lowest for methyl ester DPA. A single injection of either DPA hexyl ester HCl or 3-hexyl(amino) propionitrile into the full thickness skin incision wound in rats significantly lowered the breaking strength of the wound 12 days after injection, indicating the interference with collagen cross-linking. Both agents injected into the breast adenocarcinoma in Fisher rats significantly inhibited tumor growth without any signs of local or systemic toxicity. We conclude that these lipophilic lathyrogens with prolonged effectiveness are suitable in the treatment of pathologies, consisting of excessively cross-linked or deposited collagen (fibrotic adhesions, strictures, stenosis, and scar contractures) and in the treatment of single, solitary tumors, malignant and benign.  相似文献   
26.
BackgroundFalls are a serious challenge facing individuals post-stroke. In the past decades, various fall prevention interventions have been developed. It remains unknown if any of these interventions are effective in reducing falls in this population. Such a knowledge gap could impede the effort of preventing falls in people post-stroke.Research questions1) Are there effective interventions to prevent falls among people in the post-acute and chronic stages of stroke? and 2) How do fall prevention interventions change three key fall risk factors in this population: balance, mobility, and lower limb strength?MethodsEleven databases were searched for randomized controlled trials which included falls in people post-stroke as an outcome measure. Information on the participants, training protocol, and outcome measures were collected for each study. The primary outcome is the number of fallers and the explanatory variables included mean difference and standard deviation for fall risk factors. Studies were quality appraised using the Physiotherapy Evidence Database scale and the funnel plot.ResultsThirteen studies enrolling 1352 participants were identified. Effect size quantified by the odds ratio (OR) for falls and standardized mean difference (SMD) for fall risk factors were calculated. Overall no intervention appears to be significantly more effective in preventing falls than placebo training (OR = 0.88 with a range of [0.23 3.66]; 95 % confidence interval = [0.64 1.21], p = 0.44). All interventions showed little effect in improving the fall risk factors (SMD = −0.01 to 0.06 and p-value = 0.38–0.86), except one (the combined treadmill and overground walking) which significantly improved mobility.SignificanceCurrently no program is effective in reducing falls in people post-stroke. Future studies should measure falls as a primary outcome based on a consistent definition of falls and reliable approaches to collect falls data.  相似文献   
27.
ObjectiveThe aim of this review was to synthesize the current understanding relating to the risks of lower body functional asymmetry with injury in athletic populations.MethodsAn iterative data mining and sampling approach was used to construct a search phrase from key words, which were used to identify studies within SPORTdiscus, Medline and Academic Search Complete databases. Additional references were sourced from the reference lists of these articles.ResultsAfter screening, 31 papers were reviewed, from an initial search identifying 302 possible studies. A total of 6228 participants were involved in the studies, of which soccer players were the most observed sporting demographic (n = 2171). Of the 31 studies reviewed eight found no statistical association between lower limb asymmetry and injury risk, 10 studies provided partial statistically significant evidence and a further 10 provided statistically significant statistical links.ConclusionOverall moderate to lower quality evidence for functional asymmetry as a risk factor for injury in sport was observed. While the possibility of a relationship between lower limb functional asymmetry and injury risk cannot be ruled out, further higher quality investigations, adopting standardised methodologies, is required.  相似文献   
28.
ObjectivesExercise places physiological demands upon the cardiovascular system, subsequently leading to adaptations in structure and function. Different exercise modalities (endurance, strength and power) lead to distinct hemodynamic demands and, possibly, different patterns of adaptation. Our aim was to assess and compare brachial and femoral artery function and structure in elite level athletes engaged in endurance, strength and power sports.Designcross sectional comparison.Methods30 male elite athletes (runners n = 10, powerlifters n = 11, weightlifters n = 9) and 23 healthy controls were recruited. Brachial and femoral arterial diameters were assessed using ultrasound. Arterial function (brachial and femoral arteries) was determined using the flow mediated dilation (FMD) technique and body composition using body mass index (BMI) and body surface area (BSA).ResultsWeightlifters had significantly larger brachial arterial diameters compared to controls (4.39 ± 0.34 vs 3.86 ± 0.42 mm, p < 0.01). As weightlifter and power athletes had significantly higher body mass, BMI and BSA, we adjusted diameter for BSA. BSA-correction ameliorated differences in brachial artery resting diameters between athletes and controls. However, BSA-corrected femoral artery diameter was significantly larger in runners compared to controls (3.51 ± 0.28 vs 3.25 ± 0.34 mm, p < 0.05). There were no differences in brachial FMD between groups. Femoral artery FMD was significantly higher in runners and weightlifters compared to controls (p < 0.05 for both groups).ConclusionsHeterogeneous, limb-specific structural and functional vascular adaptation is evident in athletes, which may be influenced by exercise modality. Further, vascular remodelling relates to differences in body shape, specifically body composition, which should be accounted for when comparing athletes.  相似文献   
29.
The main movements of artistic swimming demand various physical capacities such as flexibility, strength, power, and muscular endurance. The use of ergogenic resources to potentialize performance in this sport, however, is underexplored and deserves investigation. In the present study, we tested whether caffeine ingestion would improve the execution of movements that are essential in a typical figure competition or routines in artistic swimming (i.e., amplitude in the Ariana, height in the Boost and Barracuda, and time maintained in the Stationary Scull techniques). Sixteen experienced female athlete artistic swimmers (17.4±3.2 years of age, 5.6±2.8 years of artistic swimming practice) performed several movements of artistic swimming after having ingested a capsule containing caffeine (5 mg/kg body mass) or cellulose (placebo). Compared to the placebo, caffeine improved latero-lateral amplitude during the Ariana (P=0.035), the height of the Boost and Barracuda (P=0.028 and 0.009), and maintained duration in Stationary Sculling (P=0.012). Bayes factor analysis, however, indicated substantial evidence of a positive effect of caffeine only on the Barracuda and Stationary Scull techniques. These findings indicated that caffeine improved performance during specific artistic swimming movements. Coaches and athletes should consider caffeine ingestion in their supplementation plans.  相似文献   
30.
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