Effects Of Different Intensities Research Articles

Molecular-genetic mechanisms of regulation of dihydroflavonol reductase and transcription factor Hy5 by exogenous 5-aminolevulinic acid in winter rape plants

The effect of exogenous 5-aminolevulinic acid (ALA) on the activity of dihydroflavonol-4-reductase (DFR), the expression of the dfr gene and the hy5 gene of the transcription factor Hy5 and the light effect of different intensities in combination with the ALA action on the accumulation of anthocyanins in cotyledonous leaves of winter rape (Brassica napus L.) were studied. It was shown that the stimulation of the accumulation of anthocyanins under the exogenous ALA action at the molecular level was provided by increasing the expression level of the dfr and hy5 genes and the activity of the DFR enzyme. Increasing the light intensity from 40.5 to 66.2 μmol photons/m2·s enhanced the ability of plants to accumulate anthocyanins on average by 35 %. The ALA action at concentrations of 50, 100, 150 and 200 mg/L led to an additional increase in the accumulation of anthocyanins at the two used levels of illumination, and in a dose-dependent manner. The stimulating effect of ALA under high light intensity was much higher than in the case of lower illumination. Thus, the stimulation of the anthocyanin accumulation under illumination of 40.5 μmol photons/m2·s was 106 % when using 50 mg/L ALA, 165 % – when using 100 mg/L ALA, 222 % – in the case of 150 mg/L ALA and 350 % – under the action of 200 mg/L ALA compared with light control without of ALA treatment. At an illumination of 66.2 μmol photons/m2·s, these indicators were 164, 262, 359 and 583 % respectively. Thus, it was demonstrated that the stimulation of the accumulation of anthocyanins under the action of ALA in winter rape plants was due to its positive effect on the transcription of the dfr and hy5 genes at the molecular level.

Effects Of Different Intensity And Duration Of Warm-up On Hemodynamics, Jump Power, And Flexibility.

PURPOSE: Tabata protocol (TP), usually consisting of eight to nine bouts of 20-sec of maximal exercise with 10-sec rest, is time-efficient intervention with both aerobic and anaerobic benefits. This study investigated the effectiveness of different variations of TP as a warm-up procedure. METHODS: Twenty-five healthy subjects (13 females and 12 males) participated in this study. Participants performed 6 randomized exercise sessions separated by at least 48 hours. The exercise sessions involved 3-min (TP3-20:10; TP3-30:10), 5-min (TP5-20:10; TP5-30:10) or 8-min (TP8-20:10; TP8-30:10) consecutive bodyweight squats of either 20-sec workout with 10-sec rest (20:10) or 30-sec workout with 10-sec rest (30:10). Heart rate (HR), blood pressure (BP), thigh skin surface temperature (TT), vertical jump performance (VJ), and flexibility (F) were measured before and after execution of the protocols. Countermovement jump was used to measure VJ and sit-and-reach test was used for measuring F. RESULTS: Two-way ANOVA demonstrated significant condition∗time interaction (p<0.01) and time main effect (p<0.01) for F. Significant condition∗time interaction (p<0.01) and condition (p<0.01) and time main effects (p<0.01) were observed for HR. There were significant main effects for time with the post-test demonstrating higher values than the pre-test values for both SBP and DBP (p<0.01). Significant time main effect (p<0.01) was also noted for TT indicating reduction in TT following exercise bouts. CONCLUSIONS: The findings are suggestive of a decrease in F following a higher duration of exercise (TP8-20:10 and TP8-30:10). This may be ascribed to greater accumulation of metabolites (lactic acid, ammonia, and hydrogen ion) in the working muscles, which may alter Type III and IV afferent neural activity to increase pain perception. Local tissue acidosis also stimulates bradykinin release, which may contribute to the transmission of nociceptive signals from skeletal muscle. Additionally, higher duration of exercise may increase cortisol level that decreases the pain threshold level. Therefore, the decreases in flexibility may be explained by one or a combination of metabolic, hormonal, and neurobiological changes stimulating the brain to inhibit the muscular response.

EFECTO DEL EJERCICIO AGUDO SOBRE LA FILTRACIÓN GLOMERULAR DE ADULTOS MAYORES

Introducción: Existe una disminución de la Filtración Glomerular (FG) en adultos mayores y la práctica del ejercicio puede causar cambios en la función renal. Objetivo: Evaluar el efecto de diferentes intensidades de ejercicio agudo sobre la filtración glomerular en adultos mayores. Método: 20 adultos mayores aparentemente sanos de 69,8 ± 4 años realizaron 3 pruebas de ejercicio físico: máxima y 2 sub-máximas (80% y 60%). Se colectaron muestras de sangre venosa para estimar la filtración glomerular por creatinina, antes y después del ejercicio. Resultados: Se observó una disminución significativa post-ejercicio en la filtración glomerular, estimada a partir de creatinina sérica en las pruebas máxima y sub-máxima a 80% (p &lt; 0,05). Conclusión: El ejercicio físico agudo máximo y sub-máximo al 80% de intensidad en adultos mayores aparentemente sanos, provoca una disminución de la filtración glomerular.

Moderate disturbance increases the PLFA diversity and biomass of the microbial community in biocrusts in the Loess Plateau region of China

Biological soil crusts (biocrusts) play key roles in dryland ecosystems. Examining the effects of different intensities of disturbance on biocrusts and exploring appropriate disturbance levels can provide important information about ecosystem processes and services in drylands. Five disturbance intensities ranging from 10% to 50% based on the percentage of broken biocrusts were implemented to examine the effects of simulated goat trampling on microbial communities; microbial community structure was measured with the phospholipid fatty acid method. The effects of disturbance on the biocrusts were closely related to disturbance intensity. Surprisingly, moderate disturbance had a weak effect on total biocrust coverage but increased cyanobacterial coverage by 2 ~ 3%. Consequently, there was an increase in total N, a reduction in the C/N ratio and improvements in soil moisture, and these effects led to 13 ~ 21% and 5 ~ 6% increases in microbial biomass and diversity, respectively, compared with those in undisturbed biocrusts. However, high-intensity disturbance substantially reduced biocrust coverage and microbial abundance. The study supports the intermediate disturbance hypothesis and suggests that moderate disturbance has positive effects on the microbial communities of biocrusts. These findings provide vital information for the ecological management of drylands.

Short-term effect of physical activity on sleep health: A population-based study using accelerometry

BackgroundRegular physical activity (PA) is an important behavior in improving sleep health. However, the short-term effects of PA on sleep are still controversial. This study aimed to verify the effect of different intensities of PA practiced in different periods of the day on the subsequent sleep night in a population-based cohort of young adults. Methods: Prospective analyses were conducted for PA performed during the day and its effect on the following sleep night using data from the 22-year follow-up of the 1993 Pelotas Birth Cohort in Brazil (mean age of participants = 22.6 years). Wrist-worn accelerometry was used to measure both PA and sleep parameters. Regarding intensity, we analyzed the sleep effect of light PA (LPA), moderate PA, and vigorous PA, stratified by sex. Sleep variables were sleep time window (STW; the difference between sleep onset and sleep end), total sleep time (TST; the sum of minutes classified as sleep in STW), and sleep percent (SP; SP = (TST/STW); expressed in percentage). We performed generalized estimating equations using Stata software. Results: The means of STW, TST, and SP were 443.6 min/day, 371.1 min/day, and 84%, respectively. Time spent in moderate PA and vigorous PA in the morning and afternoon was not associated with sleep variables. Among men, 10 min/day of morning LPA increased TST by 2.56 min/day. Among women, 10 min/day of morning LPA increased SP by 0.15 percentage points. Afternoon LPA also increased SP by 0.09 percentage points for women. Night PA seems to have an inverse effect on sleep variables for any intensity and both sexes. Conclusion: The effect of PA on sleep health is intrinsically related to the period of the day in which it is performed. The effect magnitude is different between sexes. For better sleep health, it is preferable that PA be performed during the day.

Effect of Different Intensities of Ultrasound on Pain and Myoelectric Activities of Upper Trapezius Myofascial Trigger Points

Effect of Different Intensities of Ultrasound on Pain and Myoelectric Activities of Upper Trapezius Myofascial Trigger Points

Effects of in‐vitro exercise‐induced endothelial shear stress on adhesion molecule gene expression

BackgroundExercise‐Induced Shear Stress (ESS) is characterized as a mechanical stimulus effecting cellular morphology and physiology. Varying ESS intensity elicit different response mechanisms through cellular signaling pathways. Higher intensity ESS enhances the expression of genes involved in protection against atherosclerosis. Adhesion molecules expression is common in atherosclerosis. Therefore, the purpose of this study was to determine the effects of different intensities of pulsatile ESS on vascular cell adhesion molecule‐1 (VCAM1) and intercellular adhesion molecule (ICAM1) gene expression.MethodsCommercially available human carotid artery endothelial cells (Sigma Aldrich) were cultured until 95–100% confluence and then exposed to pulsatile resting ESS (18 dynes/cm2) for 5 hours, followed by 1 hour low‐intensity ESS (35 dynes/cm2), or high‐intensity ESS (80 dynes/cm2) on parallel fluidic units (Ibidi, USA). Ibidi Pump Control Software (version 1.5.4, Ibidi, USA) was used to control shear stress intensity. mRNA was extracted and expression of VCAM1 and ICAM1 was assessed using qRT‐PCR. Samples were run in Changes in gene expression were calculated using the ΔΔ‐CT method, using GAPDH as the normalizing control gene. One‐way ANOVA was used to asses statistically significant differences (p &lt; 0.05) using Prism version 8 (Graphpad).ResultsThe mRNA expression of VCAM1 and ICAM1 significantly increased (p &lt;0.01). 6 and 8 folds respectively after exposure to low‐intensity ESS. Furthermore, high‐intensity ESS did not significantly increased the expression of VCAM1 and ICAM1.ConclusionLow‐intensity pulsatile exercise‐induced shear stress improves endothelial function in‐vitro through the increase in adhesion molecule’s gene expression.

Application of Micro-CT in the Examination of the Influence of Different Intensities of Exercise on the Injury of Junction of Bone and Tendon

The purpose of this study was to investigate the effect of different intensities of exercise on the injury of the junction of bone and tendon. In this study, the feasibility of Micro-CT technology to calculate the thickness of fibrous cartilage band was investigated experimentally. Adult female New Zealand white rabbits were selected as the study subjects and randomly selected into 4-week cyclic load group (n = 8) and 8-week cyclic load group (n = 8). Among them, left hind limb was used for experiment and right hind limb was used as blank control. The results showed that the tissue morphology of the bone tendon junction was changed in each load group, while the tendon cell density was significantly increased in the high-exercise load group, and there was no significant difference in the thickness of the fibrous cartilage band. Micro-CT calculation results of bone mass and trabecular bone showed no significant difference between the experimental group and the control group. Therefore, it can be concluded that the intervention of different strength load train and rest on the injury of the junction of the patella and tendon can change the fine structure of the bone, but not the tissue changes of the junction of bone and tendon, and the bone reconstruction and recovery ability is stronger than the junction of bone and tendon.

The effect of forest degradation intensity on soil function indicators in northern Iran

The degradation of forest ecosystems has an important role in global warming through the carbon (C) and nitrogen (N) cycles. The response of soil organic matter fractions and microbial activities to forest degradation has been poorly studied. The purpose of the current research was to evaluate the effect of different intensities (i.e. low, moderate, and high) of forest degradation in northern Iran on the fractions of particulate and dissolved organic matter, microbial and enzyme activities as indicators of soil function. In this research, a total of 15 soil samples (30 × 30 × 10 cm) from each studied forest sites were transferred to the laboratory. Fifty-two soil characteristics of those forest ecosystems were studied by principal component analysis (PCA), with an explanation of more than 55% of the variance by axes 1 and 2. The fractions of soil organic matter (particulate and dissolved organic matter), fertility, microbial activities (microbial respiration and microbial biomass of carbon, nitrogen, and phosphorous), enzyme indices (urease, acid phosphatase, arylsulfatase, invertase, geometric mean of enzyme activities, and Shannon’s diversity index), and stoichiometry of enzyme activity/organic C were enhanced at sites with low degradation intensity. Instead, all studied soil characteristics were suppressed at sites showing high forest degradation. The stoichiometry of enzyme activity/microbial biomass of C were not significantly different among the studied stands. It was concluded that the degradation intensity of natural forests can play a very important role in the soil function of temperate ecosystems.

Evaluation of the effects of different intensities of forced running wheel exercise on oxidative stress biomarkers in muscle, liver and serum of untrained rats.

Exercise induces different effects on antioxidant status depending on its intensity. The forced running wheel (FRW) model maintains a constant intensity and volume during exercise. The aim of the present study was to investigate the effects of FRW exercise at different running speeds on several serum biochemical parameters of liver and muscle functions and on oxidative stress biomarkers in skeletal muscle, liver and serum in the rat. Thirty-six male Wistar rats were randomly divided into six groups. Five groups participated in constant power tests at intensities of 10, 13, 14.5, 16, and 17.5 m/min, and a non-exercise group was chosen as the control. Serum, muscle and liver tissues were collected after the tests and analyzed. At speeds >16 m/min, exercise on an FRW significantly increased several serum biochemical parameters, malondialdehyde level and superoxide dismutase activity in all tissues of exercise rats compared with control rats; FRW exercise also increased catalase activity in the liver and glutathione S-transferase activity in muscle, whereas it decreased glutathione level in all tissues and catalase activity in muscle and serum. These data suggest that FRW exercise in rats activates an adaptation of the antioxidant system response in skeletal muscle at speeds <16 m/min, whereas it induces oxidative stress at higher speeds in muscle, liver and serum. In addition, we observed a correlation between the systematic and local oxidative stress status in rats after exercise on FRW.

Increased leg muscle fatigability during 2mA and 4mA transcranial direct current stimulation over the left motor cortex.

Transcranial direct current stimulation (tDCS) using intensities ≤ 2mA on physical and cognitive outcomes has been extensively investigated. Studies comparing the effects of different intensities of tDCS have yielded mixed results and little is known about how higher intensities (> 2mA) affect outcomes. This study examined the effects of tDCS at 2mA and 4mA on leg muscle fatigability. This was a double-blind, randomized, sham-controlled study. Sixteen healthy young adults underwent tDCS at three randomly ordered intensities (sham, 2mA, 4mA). Leg muscle fatigability of both legs was assessed via isokinetic fatigue testing (40 maximal reps, 120°/s). Torque- and work-derived fatigue indices (FI-T and FI-W, respectively), as well as total work performed (TW), were calculated. FI-T of the right knee extensors indicated increased fatigability in 2mA and 4mA compared with sham (p = 0.01, d = 0.73 and p < 0.001, d = 1.61, respectively). FI-W of the right knee extensors also indicated increased fatigability in 2mA and 4mA compared to sham (p = 0.01, d = 0.57 and p < 0.001, d = 1.12, respectively) and 4mA compared with 2mA (p = 0.034, d = 0.37). tDCS intensity did not affect TW performed. The 2mA and 4mA tDCS intensities increased the fatigability of the right knee extensors in young, healthy participants, potentially from altered motor unit recruitment/discharge rate or cortical hyperexcitability. Despite this increase in fatigability, the TW performed in both these conditions was not different from sham.

Effects of different intensities and durations of aerobic exercise training on arterial stiffness.

[Purpose] In the present study, we investigated the effects of regular aerobic training with different intensities and durations on new indices of arterial stiffness measured via an upper-arm oscillometric device. [Participants and Methods] We gathered data from 41 middle-aged and older people (age 65.0 ± 11.7 years). Participants were randomly divided into five groups: (1) 15 minutes of low intensity aerobic training (n=10); (2) 30 minutes of low intensity training (n=7); (3) 15 minutes of moderate-intensity training (n=9); (4) 30 minutes of moderate-intensity training (n=8); and (5) a non-training group (n=7). Training was conducted for 8 weeks, three times per week. Arterial pulse wave index, arterial pressure-volume index, brachial-ankle and heart-brachial pulse wave velocity, cardio-ankle vascular index, brachial and ankle blood pressure, heart rate, and peak oxygen uptake were measured before and after the intervention. [Results] All indicators of arterial stiffness and brachial and ankle blood pressure in the exercise groups were significantly lower after versus before the intervention. Peak oxygen uptake did not differ before versus after the intervention. [Conclusion] The present findings indicate that regular aerobic exercise may be important in reducing arterial stiffness regardless of the intensity or duration of aerobic exercise.

Feature Extraction and Intelligent Identification of Induced Polarization Effects in 1D Time-Domain Electromagnetic Data Based on PMI-FSVM Algorithm

The transient electromagnetic method can obtain resistivity and chargeability simultaneously in polarizable medium detection. Typically, we assume that the earth may contain a chargeable medium if the electromagnetic (EM) data appear negative values or sign reversals. Unfortunately, with barely perceptible characteristics, some EM responses with the induced polarization (IP) effects are considered to be non-polarizable responses. Insufficient understanding of features and inaccurate identification of the IP responses limits the use of the IP effects for broader purposes. For these reasons, we perform 1D forward modeling to discuss the degree of EM response affected by the IP effects and to extract polarization characteristics. To identify the IP effects, we combine partial mutual information (PMI) and the fuzzy support vector machine (FSVM) methods to complete the intelligent identification algorithm. We verify the efficiency and practicality of the algorithm by building Debye loops in field experiments. From the analysis, we distinguish the strong and weak IP effects by introducing the impact ratio. The strong IP responses manifest fast decays and sign reversals, and the weak IP responses primarily show fast decays or outward concavity. The identification algorithm validation results show that the recognition accuracy reaches 90.7%. In the field experiment verification, the Debye loop successfully simulates the IP effects of different intensity, and the identification results indicate that the algorithm has potential in the measured data. With this intelligent identification algorithm, the measurements can provide access to the weak polarizable medium when the impact ratio exceeds 30%.

The Effects of Different Intensity of Thinning on the Development in Scots Pine (Pinus sylvestris L.) Stands in Kazakh Uplands

The search for more accurate methods of predicting the growth and development of forest stands became the most urgent task set for foresters of Kazakhstan to determine the permissible interventions in the natural course of the life of plantings, provide high durability and resilience in forests. The aim of the study was to identify the effects of diameter and density of Scots pine stands of Kazakh Uplands on their growth and productivity and the related productivity of single plantation stands taking into account the conditions of growth and development of internal factors as well as further study of the methodology for assessing the forestry cost-effectiveness and improvement thinning. To achieve this aim, effects of varied felling intensities on Scots pine stands were studied. The most common two forest types in upland Scots pine forests were chosen as permanent sample plots; the dead pine-lichen and moss pine-grass. The results showed that improvement thinning of moderate and severe intensity which are more profitable should be done in Scots pine forests of Kazakh Upland as well as carrying out such thinning increases the yield of the larger logs and increases the value of the left stand.

Clipping defoliation and nitrogen addition shift competition between a C3 grass (Leymus chinensis) and a C4 grass (Hemarthria altissima).

Human-induced disturbances, including grazing and clipping, that cause defoliation are common in natural grasslands. Plant functional type differences in the ability to compensate for this tissue loss may influence interspecific competition. To explore the effects of different intensities of clipping and nitrogen (N) addition on compensatory growth and interspecific competition, we measured accumulated aboveground biomass (AGB), belowground biomass (BGB), tiller number, non-structural carbohydrates concentrations and leaf gas exchange parameters in two locally co-occurring species (the C3 grass Leymus chinensis and the C4 grass Hemarthria altissima) growing in monoculture and in mixture. For both grasses, the clipping treatment had significant impacts on the accumulated AGB, and the 40% clipping treatment had the largest effect. BGB gradually decreased with increasing defoliation intensity. Severe defoliation caused a significant increase in tiller number. Stored carbohydrates in the belowground biomass were mobilised and transported aboveground for the growth of new leaves to compensate for clipping-induced injury. The net CO2 assimilation rate (A) of the remaining leaves increased with clipping intensity and peaked under clipping intensities of 20% or 40%. Nitrogen addition, at a rate of 10g·N·m-2 ·year-1 , enhanced A of the remaining leaves and non-structural carbohydrate concentrations, which benefited plant compensatory growth, especially for the C3 grass. Under the mixed planting conditions, the clipping and N addition treatments lowered the competitive advantage of the C4 grass. The results suggest that a combination of defoliation and N deposition have the potential to benefit the coexistence of C3 and C4 grasses.

Intensity-dependent effect of pulsed and continuous therapeutic ultrasound on endothelial function: a randomised crossover clinical trial

Background/Aims The aim of this study was to evaluate the effects of different intensities and waveforms of therapeutic ultrasound on endothelial function in typically healthy participants. Methods A total of 15 participants were evaluated over 2 consecutive days. Different intensities of continuous and pulsed (20% duty cycle) 1-MHz ultrasound were applied to the brachial artery for 5 minutes each. Endothelial function was measured using flow-mediated dilation technique before and immediately after ultrasound was applied. Results Compared to baseline values, endothelium-dependent vasodilation increased with both continuous (2.8%) and pulsed (1.6%) ultrasound at an intensity of 0.4 W/cm2SPTA. At 1.2 W/cm2SPTA, endothelium-dependent vasodilation was 4.1% above baseline for pulsed and 5.3% above baseline for continuous waveforms. There was no additional increase in vasodilation at intensities above 1.2 W/cm2SPTA. The percentage of endothelium-dependent vasodilation was similar for the all of the different waveforms studied. Conclusions Both continuous and pulsed ultrasound waveforms promote endothelium-dependent vasodilation. There was a dose-dependent increase in vasodilation at intensities from 0.4 W/cm2SPTA to 1.2 W/cm2SPTA. Pulsed is more efficient than continuous ultrasound because it produces the same effect on endothelium-dependent vasodilation while employing 20% of the energy applied with continuous ultrasound.

Impact of different intensities of forced exercise on deficits of spatial and aversive memory, anxiety-like behavior, and hippocampal BDNF during morphine abstinence period in male rats.

Forced exercise can alleviate cognitive-behavioral deficits in an experimental model of addiction. However, the effects of different intensities of forced exercise in improving behavioral, cognitive and biochemical deficits during morphine abstinence period are not well investigated. Thus, the current work examined the effects of different loads of forced exercise on cognition functions, anxiety behavior and BDNF changes in the hippocampus, and prefrontal cortex (PFC), and also serum levels of BDNF and corticosterone during the abstinent period in male rats. Animals received morphine injections (10mg/kg, twice a day) for 10 consecutive days. Then, the animals were exposed to a 4-week forced exercise training program under low, moderate or high intensities (30min per session on 5days a week), which accompanied by behavioral and biochemical tests. In Experiment 1, anxiety-like behaviors using elevated plus maze (EPM), and light/dark box (L/D box) were examined. In Experiment 2, cognitive functions using T-maze alteration and passive avoidance tasks were tested, which accompanied by BDNF measurements in the hippocampus and PFC. In Experiment 3, serum levels of BDNF and corticosterone following the termination of forced exercise regimen were measured. Morphine-abstinent animals exhibited anxiogenic -like behaviors in the EPM, but not L/D box. They also exhibited impaired T-maze alternation performance and passive avoidance memory, and a decline in hippocampal BDNF, but not PFC. Forced exercise at a moderate intensity alleviated anxiety, cognitive and BDNF defects in morphine-abstinent animals. The high load exercise enhanced serum levels of corticosterone in both saline and morphine groups. Thus, regular moderate forced exercise may be beneficial in preserving cognitive and mood functions in male addicts during the abstinent period and drug rehabilitation.

Effects of Different Intensities of Circuit Resistance Training on Plasma level of High-Density Lipoprotein Subfractions and Apolipoprotein M in Untrained Young Men

Effects of Different Intensities of Circuit Resistance Training on Plasma level of High-Density Lipoprotein Subfractions and Apolipoprotein M in Untrained Young Men

Impact of Rainfall Variation on Slope Made of Expansive Yazoo Clay Soil in Mississippi

Yazoo clay soil is highly expansive in nature and extends over central Mississippi, Alabama, and Southern Louisiana. Shallow slope failure is frequent in embankments constructed using Yazoo clay due to rainfall volume and climatic variation. This study investigates the effect of different intensities and volumes of rainfall on slopes constructed of Yazoo clay soil in Mississippi. The coupled flow-deformation analysis was conducted using the finite element method (FEM) in PLAXIS to investigate the unsaturated hydromechanical behavior of the slopes. Weathered Yazoo clay soil samples were collected and tested in laboratory conditions to investigate the soil index properties, soil strength parameters, and soil water characteristics curve. The historical rainfall pattern of Mississippi from National Oceanic and Atmospheric Administration (NOAA) is evaluated at different intensities (2 to 50 mm/h) and duration of rainfall (30 min to 7 days) based on return periods of 50, 100, and 500 years. Three fill slopes constructed using Yazoo clay soil, with slope ratios of 2H:1V, 3H:1V, and 4H:1V, are investigated. The rainfall pattern is applied to the top boundary of the slope in PLAXIS. The investigation results indicated that rainfall water infiltrated the top part of the slope, near the crest, resulting in the reduction of both the matric suction and the factor of safety of the slope.

Effects of different intensities of endurance training on serum fibroblast growth factor level, glucose, and insulin resistance in streptozotocin-diabetic male rats

Background and aims: Fibroblast growth factor 21 (FGF21) is a myokine which is produced and secreted by skeletal muscle. Given the inconsistent results on the relationship between the intensity of training and the improvement of blood indices in diabetic patients, the current research investigated the effect of endurance training at different intensities on serum FGF21 level, glucose, and insulin resistance in streptozotocin (STZ)-diabetic male rats. Methods: To this end, 50 rats (with a mean weight of 23.28±25.05 g) were randomly divided into healthy (non-diabetic) control, diabetic control, as well as low, moderate, and high-intensity endurance training groups. Diabetes was induced in all rats by the injection of STZ. Three days after STZ injection, the blood samples were taken from the cut tip of the tails, and those rats with blood glucose levels above 300 mg/dL were considered diabetic and included in the study. The program included 8-week aerobic training at different intensities. The blood samples (5 cc) were directly collected from the hearts 48 hours after the last training session, followed by measuring the serum FGF21 level, glucose, and insulin. Finally, the analysis of variance and Bonferroni post-hoc test were used for inter-group comparison and the significance level was considered &lt;0.05. Results: Based on the results, the serum glucose level, insulin resistance, and FGF21 reduced after eight weeks of endurance training. The reduction of FGF21 in higher intensity endurance training group was greater compared to the other groups (P&lt;0.05) and the reduction of glucose in moderate intensity group was more significant in comparison to that of the other groups (P&lt;0.001). However, the insulin level increased, which was more pronounced in the moderate intensity training group compared to the other groups (P=0.002). Conclusion: Overall, both moderate and high-intensity endurance training led to a comparatively more effective reduction in blood glucose and insulin resistance. Therefore, these two parameters may have a protective effect on the complications associated with diabetes in the rats.