RELIABILITY OF A SIMPLE NOVEL FIELD TEST FOR THE MEASUREMENT OF PLANTAR FLEXOR MUSCLE STRENGTH

ABSTRACT Introduction When a person is in a standing position, the plantar flexor muscles are involved in most static and dynamic body movements. Objectives The aim of this study was to investigate the trial to trial and factorial reliability of measuring the contractile characteristics of PF muscles using a simple novel field test. Methods The sample consisted of 452 healthy subjects, 120 male and 332 female. The research was conducted by means of the trial to trial testing method, using isometric dynamometry performed in field conditions. ANOVA was used to estimate the differences among the trials, Cronbach’s alpha and interclass correlation to estimate the correlations among the trials, and principal component analysis to evaluate the contribution of each trial to overall variability. Results The main findings of this study are that trials differed significantly (p<0.000) for maximal force (Fmax) and maximal rate of force development (RFDmax), indicating that the three procedural trials were necessary. The trials were highly correlated (Fmax, RFDmax, r>0.9), proving that measuring was reliable, and the factorial analysis separated the second and third trials, the second trial accounting for most of the total variability. Conclusions The simple novel field test for the measurement of plantar flexor contractile characteristics recommended by this study proved to be as highly reliable as laboratory testing, but was easy to perform in conditions outside of scientific or diagnostic institutions, which greatly facilitates the work of scientists, coaches and professionals. Level of Evidence II; Diagnostic Studies – Investigating a diagnostics test.

Download Full-text

Genetic components of potato chip quality evaluated in three environments and under various storage regimes

Canadian Journal of Plant Science ◽

10.4141/cjps92-067 ◽

1992 ◽

Vol 72 (2) ◽

pp. 535-543 ◽

Cited By ~ 2

Author(s):

D. R. Lynch ◽

G. C. C. Tai ◽

R. H. Coffin

Keyword(s):

Specific Gravity ◽

Combining Ability ◽

Principal Component ◽

Chip Color ◽

Narrow Sense Heritability ◽

Genetic Components ◽

New Information ◽

Total Variability ◽

Highly Correlated ◽

Chipping Quality

A diallel series of crosses was made between parents with good processing quality and nonprocessing but well-adapted varieties and breeding clones to study the inheritance of chipping quality and tuber yield in potatoes. The progeny of the crosses were assessed in three widely differing growing environments and chipped from a range of storage environments. Principal component analysis for chip color indicated that the first (PCA1) and second (PCA2) principal components accounted for 84.4 and 5.0% of the total variability, respectively. PCA1 scores were highly correlated (P < 0.01) with the mean chip color scores of the 20 crosses measured over the 11 environments, whereas PCA2 scores were highly correlated (P < 0.01) with the standard deviations of the chip scores over storage environments. These results provide new information that supports the recently proposed concept of two genetically independent systems determining chip color, i.e., "overall chipping quality" and "chipping stability". Highly significant (P < 0.01) general combining-ability and nonsignificant specific combining-ability effects suggest additive genetic factors and high narrow-sense heritability for specific gravity. Combining-ability effects for yield traits were generally nonsignificant, which probably reflects the selection of parents with proven breeding value.Key words: Solanum tuberosum, stability, yield, specific gravity

Download Full-text

EFFECT OF FOOTBALL ON REHABILITATION OF ANKLE INJURY PATIENTS

Revista Brasileira de Medicina do Esporte ◽

10.1590/1517-8692202228012021_0448 ◽

2022 ◽

Vol 28 (1) ◽

pp. 62-64

Author(s):

Jie Liu

Keyword(s):

Sports Injuries ◽

Muscle Tone ◽

Good Effect ◽

Plantar Flexor ◽

Plantar Flexors ◽

Flexor Muscle ◽

Level Of Evidence ◽

Balance Ability ◽

Speed Training ◽

The Right

ABSTRACT Introduction: Brief introduction: Ankle tendon and ligament sports injuries are common in football players. Objective: To continue to improve special strength training related to the characteristics of football after rehabilitation of injured ankle tendons and ligaments. Methods: Two master football sportsmen were rehabilitated by multi-point equal-length, short-arc and long-arc equal-speed training combined with balance ability exercises. Results: There were two long muscle L be maintain muscle tone plantar flexors force four times of 96 n/m, n/m 121, 140 n/m, 145 n/m than back flexors force of 63 n/m, 52 n/m, 60 n/m, 74 n/m tall. Plantar flexor fatigue was 57%, 30%, 29%, 12%, 28%, 18%, 20%, 21%. Conclusions: With the passing of time, the relative peak moment value of the right ankle plantar flexor muscle group of the two patients kept rising, the dorsiflexor muscle was basically flat, and the work fatigue index decreased step by step, indicating that the right ankle muscle strength level was significantly improved, the anti-fatigue ability was improved, and the rehabilitation treatment had a good effect. Level of evidence II; Therapeutic studies - investigation of treatment results.

Download Full-text

Suitability Analysis of 17 Probiotic Type Strains of Lactic Acid Bacteria as Starter for Kimchi Fermentation

Foods ◽

10.3390/foods10061435 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1435

Author(s):

Hee Seo ◽

Jae-Han Bae ◽

Gayun Kim ◽

Seul-Ah Kim ◽

Byung Hee Ryu ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Growth Rates ◽

Principal Component ◽

Fermented Foods ◽

Suitability Analysis ◽

Moderate Growth ◽

Health Promoting ◽

Highly Correlated ◽

Type Strains

The use of probiotic starters can improve the sensory and health-promoting properties of fermented foods. This study aimed to evaluate the suitability of probiotic lactic acid bacteria (LAB) as a starter for kimchi fermentation. Seventeen probiotic type strains were tested for their growth rates, volatile aroma compounds, metabolites, and sensory characteristics of kimchi, and their characteristics were compared to those of Leuconostoc (Le.) mesenteroides DRC 1506, a commercial kimchi starter. Among the tested strains, Limosilactobacillus fermentum, Limosilactobacillus reuteri, Lacticaseibacillus rhamnosus, Lacticaseibacillus paracasei, and Ligilactobacillus salivarius exhibited high or moderate growth rates in simulated kimchi juice (SKJ) at 37 °C and 15 °C. When these five strains were inoculated in kimchi and metabolite profiles were analyzed during fermentation using GC/MS and 1H-NMR, data from the principal component analysis (PCA) showed that L. fermentum and L. reuteri were highly correlated with Le. mesenteroides in concentrations of sugar, mannitol, lactate, acetate, and total volatile compounds. Sensory test results also indicated that these three strains showed similar sensory preferences. In conclusion, L. fermentum and L. reuteri can be considered potential candidates as probiotic starters or cocultures to develop health-promoting kimchi products.

Download Full-text

Plantar flexor muscle stretching depresses the soleus late response but not tendon tap reflexes

European Journal of Neuroscience ◽

10.1111/ejn.15178 ◽

2021 ◽

Author(s):

Timothy S. Pulverenti ◽

Gabriel S. Trajano ◽

Benjamin J. C. Kirk ◽

Vanesa Bochkezanian ◽

Anthony J. Blazevich

Keyword(s):

Late Response ◽

Plantar Flexor ◽

Flexor Muscle ◽

Muscle Stretching ◽

Tendon Tap

Download Full-text

Feed efficiency of lactating Holstein cows is less reproducible when changing dietary starch and fibre concentrations than within diet over subsequent lactation stages

10.1101/2021.02.10.430560 ◽

2021 ◽

Author(s):

Amélie Fischer ◽

Philippe Gasnier ◽

Philippe Faverdin

Keyword(s):

Principal Components ◽

Feed Efficiency ◽

Nir Spectroscopy ◽

Principal Component ◽

Holstein Cows ◽

Diet Change ◽

Total Variability ◽

The One ◽

The Individual ◽

Starch Diet

ABSTRACTBackgroundImproving feed efficiency has become a common target for dairy farmers to meet the requirement of producing more milk with fewer resources. To improve feed efficiency, a prerequisite is to ensure that the cows identified as most or least efficient will remain as such, independently of diet composition. Therefore, the current research analysed the ability of lactating dairy cows to maintain their feed efficiency while changing the energy density of the diet by changing its concentration in starch and fibre. A total of 60 lactating Holstein cows, including 33 primiparous cows, were first fed a high starch diet (diet E+P+), then switched over to a low starch diet (diet E−P−). Near infra-red (NIR) spectroscopy was performed on each individual feed ingredient, diet and individual refusals to check for sorting behaviour. A principal component analysis (PCA) was performed to analyse if the variability in NIR spectra of the refusals was explained by the differences in feed efficiency.ResultsThe error of reproducibility of feed efficiency across diets was 2.95 MJ/d. This error was significantly larger than the errors of repeatability estimated within diet over two subsequent lactation stages, which were 2.01 MJ/d within diet E−P− and 2.40 MJ/d within diet E+P+. The coefficient of correlation of concordance (CCC) was 0.64 between feed efficiency estimated within diet E+P+ and feed efficiency estimated within diet E−P−. This CCC was smaller than the one observed for feed efficiency estimated within diet between two subsequent lactation stages (CCC = 0.72 within diet E+P+ and 0.85 within diet E−P−). The first two principal components of the PCA explained 90% of the total variability of the NIR spectra of the individual refusals. Feed efficiency was poorly correlated to those principal components, which suggests that feed sorting behaviour did not explain differences in feed efficiency.ConclusionsFeed efficiency was significantly less reproducible across diets than repeatable within the same diet over subsequent lactation stages, but cow’s ranking for feed efficiency was not significantly affected by diet change. The differences in sorting behaviour between cows were not associated to feed efficiency differences in this trial neither with the E+P+ diet nor with the E−P− diet. Those results have to be confirmed with cows fed with more extreme diets (for example roughage only) to ensure that the least and most efficient cows will not change.

Download Full-text

Assessment of Physicochemical Properties of Tequila Brands: Authentication and Quality

Journal of Chemistry ◽

10.1155/2016/6254942 ◽

2016 ◽

Vol 2016 ◽

pp. 1-13 ◽

Cited By ~ 2

Author(s):

Alejandra Carreon-Alvarez ◽

Amaury Suárez-Gómez ◽

Florentina Zurita ◽

Sergio Gómez-Salazar ◽

J. Felix Armando Soltero ◽

...

Keyword(s):

Principal Component Analysis ◽

Cluster Analysis ◽

Refractive Index ◽

Physicochemical Properties ◽

Analysis Of Variance ◽

Principal Component ◽

Component Analysis ◽

Total Variability ◽

And Cluster Analysis ◽

Physicochemical Data

Several physicochemical properties were measured in commercial tequila brands: conductivity, density, pH, sound velocity, viscosity, and refractive index. Physicochemical data were analyzed by Principal Component Analysis (PCA), cluster analysis, and the one-way analysis of variance to identify the quality and authenticity of tequila brands. According to the Principal Component Analysis, the existence of 3 main components was identified, explaining the 87.76% of the total variability of physicochemical measurements. In general, all tequila brands appeared together in the plane of the first two principal components. In the cluster analysis, four groups showing similar characteristics were identified. In particular, one of the clusters contains some tequila brands that are not identified by the Regulatory Council of Tequila and do not meet the quality requirements established in the Mexican Official Standard 006. These tequila brands are characterized by having higher conductivity and density and lower viscosity and refractive index, determined by one-way analysis of variance. Therefore, these economical measurements, PCA, and cluster analysis can be used to determinate the authenticity of a tequila brand.

Download Full-text

A data-driven approach to measuring epidemiological susceptibility risk around the world

Scientific Reports ◽

10.1038/s41598-021-03322-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Alessandro Bitetto ◽

Paola Cerchiello ◽

Charilaos Mertzanis

Keyword(s):

Factor Model ◽

Principal Component ◽

Data Driven ◽

Dynamic Factor ◽

Country Level ◽

Epidemiological Risk ◽

Data Driven Approach ◽

Managerial Implications ◽

Total Variability ◽

Pca Method

AbstractEpidemic outbreaks are extreme events that become more frequent and severe, associated with large social and real costs. It is therefore important to assess whether countries are prepared to manage epidemiological risks. We use a fully data-driven approach to measure epidemiological susceptibility risk at the country level using time-varying information. We apply both principal component analysis (PCA) and dynamic factor model (DFM) to deal with the presence of strong cross-section dependence in the data. We conduct extensive in-sample model evaluations of 168 countries covering 17 indicators for the 2010–2019 period. The results show that the robust PCA method accounts for about 90% of total variability, whilst the DFM accounts for about 76% of the total variability. Our index could therefore provide the basis for developing risk assessments of epidemiological risk contagion. It could be also used by organizations to assess likely real consequences of epidemics with useful managerial implications.

Download Full-text

CHANGES IN THE FLEXOR AND EXTENSOR MUSCLES AT DIFFERENT SPEEDS

Revista Brasileira de Medicina do Esporte ◽

10.1590/1517-8692202127072021_0375 ◽

2021 ◽

Vol 27 (7) ◽

pp. 686-688

Author(s):

Rui Ma ◽

Wenyan Li

Keyword(s):

Knee Joint ◽

Peak Torque ◽

Muscle Group ◽

Lower Limbs ◽

Flexor Muscle ◽

Level Of Evidence ◽

Isokinetic Test ◽

Extensor Muscles ◽

Test Velocity ◽

The Difference

ABSTRACT Introduction: Centrifugal strength is an important element for strength quality. Developing muscle centrifugal strength can effectively increase the stability of lower limbs and reduce the risk of injury. Objective: To explore the characteristics of contractile force of flexor ahods in strength training and rehabilitation training, and the extensor muscles of the knee joint in athletes with different speeds of centripetal force. Methods: The knee joint muscle group of 8 first-level male high jumpers and 8 second-level male high jumpers were tested by isokinetic centrifugal contraction; the angular test velocity was 60 °/s, 120 °/s, 240 °/s, and the indexes included peak torque, relative peak torque (peak torque/body weight), and the peak torque flexural extension ratio. Results: With the centrifugal contraction of the knee joint muscle group (P < 0.05), the second-level high jumpers should increase the ability of the knee flexor muscle group of the take-off leg. In the case of constant velocity centrifugal contraction (P < 0.01), taking off time must be reduced, that is, taking off speed must be accelerated. Conclusions: The difference in the knee joint muscle isokinetic test results is one of the reasons for the difference in knee joint flexor and extensor muscle contractility under the different speed forces of high jumpers. Level of evidence II; Therapeutic studies - investigation of treatment results.

Download Full-text