Low-intensity Aerobic Training Research Articles

Correction: Acute Responses in Blood Flow Restriction Low-intensity Aerobic Training: A Meta-analysis

Correction: Acute Responses in Blood Flow Restriction Low-intensity Aerobic Training: A Meta-analysis

Acute Responses in Blood Flow Restriction Low-intensity Aerobic Training: A Meta-analysis.

The purpose was to determine the effect low-intensity training with blood flow restriction (LI-BFR) versus high-intensity aerobic training (HIT) on acute physiological and perceptual responses. The Cumulative Index to Nursing and Allied Health Literature, National Library of Medicine, Scopus, SPORTDiscus and Web of Science databases and the reference list of eligible studies were consulted to identify randomized experimental studies, published until July 4, 2022, that analyzed physiological or perceptual responses between LI-BFR versus HIT in healthy young individuals. Mean difference (MD) and standardized mean difference (SMD) were used as effect estimates and random effects models were applied in all analyses. Twelve studies were included in this review. During exercise sessions, HIT promoted higher values of heart rate (MD=28.9 bpm; p<0.00001; I 2 =79%), oxygen consumption (SMD=4.01; p<0.00001; I 2 =83%), ventilation (MD=48.03 l/min; p=0.0001; I 2 =97%), effort (SMD=1.54; p=0.003; I 2 =90%) and blood lactate (MD=3.85 mmol/L; p=0.002; I 2 =97%). Perception of pain/discomfort was lower in HIT (SMD=-1.71; p=0.04; I 2 =77.5%). In conclusion, LI-BFR promotes less pronounced physiological responses than HIT but with greater perception of pain.

Physical Activity and Post-COVID-19 Syndrome in Older Adults: A Systematic Review

Background: Physical activity (PA) may play a significant role in managing post-Coronavirus Disease (COVID)-19 syndrome, a significant public health concern among older adults. This study aimed to systematically review the evidence on post-COVID-19 symptoms, signs, risk factors, and the effects of PA programs in managing post-COVID-19 syndrome among older adults. Method: This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendation. The systematic search was conducted in August 2022 using Scopus and MEDLINE (via PubMed) databases. Results: There were 51 documents screened, among which 10 (7 observational and 3 experimental studies) met the selection criteria. The reported post-COVID-19 symptoms and signs associated with physical health included dyspnea, fatigue, diarrhea, and sarcopenia, abnormal lung function, cardiac pathology, immunological changes, reduced physical performance, respectively, while those associated with mental health included depression, poor concentration and memory, and anxiety. Patients with higher body mass indexes were more likely to experience more symptoms. Older patients had greater difficulties in performing daily activities and mobility. A multidisciplinary-based PA program is suggested to be feasible and effective in improving fatigue, ability to walk, balance, and cognitive function. For patients with sarcopenia, a low-intensity aerobic training exercise appears to improve muscle strength, kinesiophobia, and quality of life. Conclusion: Various post-COVID-19 symptoms have been reported along with their risk factors, and PA programs are potentially used for managing these symptoms. More research, however, is recommended to explore the PA program for specific post-COVID-19 symptoms.

Comparison between low, moderate, and high intensity aerobic training with equalized loads on biomarkers and performance in rats

This study investigated the physiological and molecular responses of Wistar Hannover rats, submitted to three 5-week chronic training models, with similar training loads. Twenty-four Wistar Hanover rats were randomly divided into four groups: control (n = 6), low-intensity training (Z1; n = 6), moderate-intensity training (Z2; n = 6) and high-intensity training (Z3; n = 6). The three exercise groups performed a 5-week running training three times a week, with the same prescribed workload but the intensity and the volume were different between groups. An increase in maximal speed was observed after four weeks of training for the three groups that trained, with no difference between groups. Higher rest glycogen was also observed in the soleus muscle after training for the exercise groups compared to the control group. We also found that the Z2 group had a higher protein content of total and phosphorylated GSK3-β compared to the control group after five weeks of training. In conclusion, the present study shows that five weeks of treadmill training based on intensity zones 1, 2, and 3 improved performance and increased resting glycogen in the soleus muscle, therefore intensity modulation does not change the training program adaptation since the different program loads are equalized.

Effect of Low-Intensity Aerobic Training Combined with Blood Flow Restriction on Body Composition, Physical Fitness, and Vascular Responses in Recreational Runners.

This study investigated the effect of low-intensity aerobic training combined with blood flow restriction (LABFR) on body composition, physical fitness, and vascular functions in recreational runners. The participants were 30 healthy male recreational runners, randomized between the LABFR (n = 15) and control (n = 15) groups. The LABFR group performed five sets of a repeated pattern of 2 min running at 40% VO2max and 1 min passive rest, while wearing the occlusion cuff belts on the proximal end of the thigh. The frequency was three times a week for the period of eight weeks. The control group performed the identical running protocol without wearing the occlusion cuff belts. At the end of the training, the participants’ body composition (fat mass, body fat, muscle mass, and right and left thigh circumference), physical fitness (power and VO2max), and vascular responses (flow-mediated dilation (FMD), brachial ankle pulse wave velocity (baPWV), ankle brachial index (ABI), systolic blood pressure (SBP) and diastolic blood pressure (DBP)) were measured. The results showed a significant time × group interaction effect on muscle mass (F = 53.242, p = 0.001, ηp2 = 0.664) and right thigh circumference (F = 4.544, p = 0.042, ηp2 = 0.144), but no significant variation in any other factors, including fat mass, body fat, left thigh circumference, FMD, baPWV, ABI, SBP, and DBP (p > 0.05). Overall, our results suggested that eight-week LABFR exerted a positive effect on the body composition, especially muscle mass and thigh circumference, of recreational runners.

Effects of Low-Intensity and Long-Term Aerobic Exercise on the Psoas Muscle of mdx Mice: An Experimental Model of Duchenne Muscular Dystrophy.

Duchenne muscular dystrophy (DMD) is a muscle disease characterized by the absence of the protein dystrophin, which causes a loss of sarcolemma integrity, determining recurrent muscle injuries, decrease in muscle function, and progressive degeneration. Currently, there is a need for therapeutic treatments to improve the quality of life of DMD patients. Here, we investigated the effects of a low-intensity aerobic training (37 sessions) on satellite cells, peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1α protein (PGC-1α), and different types of fibers of the psoas muscle from mdx mice (DMD experimental model). Wildtype and mdx mice were randomly divided into sedentary and trained groups (n = 24). Trained animals were subjected to 37 sessions of low-intensity running on a motorized treadmill. Subsequently, the psoas muscle was excised and analyzed by immunofluorescence for dystrophin, satellite cells, myosin heavy chain (MHC), and PGC-1α content. The minimal Feret’s diameters of the fibers were measured, and light microscopy was applied to observe general morphological features of the muscles. The training (37 sessions) improved morphological features in muscles from mdx mice and caused an increase in the number of quiescent/activated satellite cells. It also increased the content of PGC-1α in the mdx group. We concluded that low-intensity aerobic exercise (37 sessions) was able to reverse deleterious changes determined by DMD.

Influence of Low Intensity Aerobic Exercise Training on the Vo2 Max in 11 to 14 Years School Girls in Hyderabad District

Exercise training with varying intensity increases maximal oxygen intake (VO2max), a strong predictor of cardiovascular and all-cause mortality. Purpose: The aim of this study was to find out the influence of low intensity aerobic training on the vo2 max in 11 to 14 years school girls in Hyderabad district. Methodology: The research scholar has randomly selected thirty (N=30) high school girls were selected as subjects and their age ranged between 11 to 14 years. The subjects were divided into two equal groups, each group consist of 15 total 30. Group one acted as experimental group (EG) and group two acted as control group (CG). The dependent variable vo2 max was selected and it is measured by manual test. Statistical Tool: The statistical tool paired sample „t‟ test was used for analysing of the data and the obtained „t‟ ratio was tested for significance at 0.05 level of confidence. Results: The analysis of the data revealed that there was a significant improvement on vo2 max by the application of low intensity aerobic.

A Comparison of the Effect of Physical Activity and Cognitive Training on Dual-Task Performance in Older Adults.

Studies suggest that cognitive training and physical activity can improve age-related deficits in dual-task performances. However, both of these interventions have never been compared in the same study. This article investigates the improvement in dual-task performance in 2 types of exercise training groups and a cognitive training group and explores if there are specific dual-task components that are more sensitive or more likely to improve following each type of training. Seventy-eight healthy inactive participants older than the age of 60 (M = 69.98, SD = 5.56) were randomized to one of three 12-week training programs: aerobic training (AET) = 26, gross motor abilities (GMA) = 27, and cognition (COG) = 25. Before and after the training program, the participants underwent physical fitness tests, and cognitive evaluations involving a computerized cognitive dual task. The AET consisted of high- and low-intensity aerobic training, the GMA of full-body exercises focusing on agility, balance, coordination, and stretching, and the COG of tablet-based exercises focusing on executive functions. Repeated-measures analysis of variance on reaction time data revealed a group × time interaction (F(2,75) = 11.91, p < .01) with COG having the greatest improvement, followed by a significant improvement in the GMA group. Secondary analysis revealed the COG to also improve the intraindividual variability in reaction time (F(1,24) = 8.62, p < .01), while the GMA improved the dual-task cost (F(1,26) = 12.74, p < .01). The results show that physical and cognitive training can help enhance dual-task performance by improving different aspects of the task, suggesting that different mechanisms are in play.

Comparative effectiveness study of low versus high-intensity aerobic training with resistance training in community-dwelling older men with post-COVID 19 sarcopenia: A randomized controlled trial

Objective: To find and compare the clinical and psychological effects of low and high-intensity aerobic training combined with resistance training in community-dwelling older men with post-COVID-19 sarcopenia symptoms. Design: Randomized control trial. Setting: University physiotherapy clinic. Participants: Men in the age range of 60–80 years with post-COVID-19 Sarcopenia. Intervention: All participants received resistance training for whatever time of the day that they received it, and that in addition they were randomized into two groups like low-intensity aerobic training group (n = 38) and high-intensity aerobic training group (n = 38) for 30 minutes/session, 1 session/day, 4 days/week for 8 weeks. Outcomes: Clinical (muscle strength and muscle mass) and psychological (kinesiophobia and quality of life scales) measures were measured at the baseline, fourth week, the eighth week, and at six months follow-up. Results: The 2 × 4 group by time repeated measures MANOVA with corrected post-hoc tests for six dependent variables shows a significant difference between the groups (P < 0.001). At the end of six months follow up, the handgrip strength, −3.9 (95% CI −4.26 to −3.53), kinesiophobia level 4.7 (95% CI 4.24 to 5.15), and quality of life −10.4 (95% CI −10.81 to −9.9) shows more improvement (P < 0.001) in low-intensity aerobic training group than high-intensity aerobic training group, but in muscle mass both groups did not show any significant difference (P > 0.05). Conclusion: Low-intensity aerobic training exercises are more effective in improving the clinical (muscle strength) and psychological (kinesiophobia and quality of life) measures than high-intensity aerobic training in post-COVID 19 Sarcopenia.

Evaluation of the intervention of home-based pulmonary rehabilitation in patients with chronic obstructive pulmonary disease

Abstract Objective Chronic obstructive pulmonary disease (COPD) can be prevented and treated, although presenting with persistent airflow restriction; the airflow restriction caused by COPD is mostly progressive. In recent years, more attention has been paid to the home-based pulmonary rehabilitation (PR) and its influence on COPD. Exercise training is the basic constituent of PR. However, it is not clear which exercise trainings are the ideal ways to deliver home-based PR. Methods In this review, we focus on the effect of home-based exercise training on patients with COPD. We searched literature, which was necessarily required to be randomized controlled trails (RCTs) from the establishment of the four respective databases (Medline, PubMed, Web of Science, and China National Knowledge Infrastructure) from January 2008 to January 2018. We used the Cochrane collaborative “risk of bias” tool to assess the quality of evidence. A total of 21 trials (1694 participants) were included. Through the analysis of the literature, we find that a simple, low-cost, and low-intensity family-based lung-rehabilitation plan to adapt to the real life may lead to the improvement of the ability to exercise, the reduction of the difficulty in breathing, and the improvement of carrying out daily activities. Results In the exercise training of home-based PR, lower limb exercise (LLE) training demonstrated a more perceptible effect in improving the quality of life of patients with COPD. At the same time, the combination of LLE training, breathing training, and upper limb exercise training is more obvious than the simple LLE training. In addition, home-based low-intensity aerobic training may sometimes be no less than the outpatient or center intervention to improve dyspnea, health status, and exercise tolerance. In conclusion, the simple and easy home-based PR exercise program is useful. Long-term home-based PR may require an enhanced need for maintenance. Conclusions A simple, low-cost, and low-intensity high blood pressure response (HBPR) plan to adapt to the real life may lead to an augmentation in the ability to exercise, a reduction of the difficulty in breathing, and an improvement in carrying out day-to-day activities. HBPR strategies can benefit patients (elderly patients with COPD at home) in the long term.

Effect of various intensities of aerobic training on resting pulse rate

The purpose of the study was to find out the effects of different intensities of aerobic training on resting pulse rate. To achieve this purpose of the study, forty-five men students studying in the Department of Physical Education and Sports Sciences, Annamalai University, Annamalainagar, Chidambaram were selected as subjects at random. The selected subjects were divided into three equal groups of fifteen subjects each, such as low intensity aerobic training group, high intensity aerobic training group and control group. The group I underwent low intensity aerobic training programme and group II underwent high intensity aerobic training programme for three days per week for twelve weeks. Group III acted as control who did not participate any special training programmes apart from their regular physical education activities as per their curriculum. Among the physiological parameters, the following variable namely resting pulse rate was selected as criterion variable. All the subjects of three groups were tested on selected dependent variables at prior to and immediately after the training programme. The analysis of covariance was used to analyze the significant difference, if any among the groups. The .05 level of confidence was fixed as the level of significance to test the “F” ratio obtained by the analysis of covariance, which was considered as an appropriate. The results of the study revealed that there was a significant difference among low intensity aerobic training group, high intensity aerobic training group and control group on resting pulse rate. And also it was found that there was a significant reduction on resting pulse rate due to high intensity aerobic training.

The Effect of 8-Weeks of Low-Intensity Swimming Training on Promyelocytic Leukemia Zinc Finger Protein and Spermatid Transition Nuclear Protein Gene Expression in Azoospermic Rats Model

Aims: One of the causes of infertility in men is the azoospermia disease, which is attributed to the lack of sperm in each sperm. The primary function of spermatogenesis is the maintenance, proliferation, and differentiation of spermatogonial cells. Thus, the present study aimed to investigate the changes in Promyelocytic Leukemia Zinc Finger (PLZF) and spermatid Transition Nuclear Protein (TNP) gene expression levels in an azoospermic rat model after 8 weeks of low-intensity aerobic training. Methods &amp; Materials: In this experimental study, 15 adult male Wistar rats were randomly divided into three groups of healthy control, with azoospermia, and exercise plus azoospermia after creating an azoospermia model. The patient plus exercise group performed a low-intensity swimming exercise 30 minutes a day, five days a week for 8 weeks, after the creation of the azoospermic rats. A One-way ANOVA test was used for data analysis. Findings: The results showed that a period of swimming exercise program in the exercise plus azoospermia group significantly reduced PLZF gene expression compared to the healthy control groups (P=0.001) and no significant increase to the azoospermia group (P=0.06). There was also a significant decrease in TNP gene expression levels in the exercise plus azoospermia group compared to the healthy control group (P=0.001) and a significant increase in the azoospermia group (P=0.057). Conclusion: Based on these Findings, it can be stated that the alteration of key molecules or signaling pathways and expression of the PLZF and TNP genes in the spermatogenesis process may increase infertility, but regular aerobic exercise, such as low-intensity swimming, helps to control the effects of infertility by increasing the maintenance and development of spermatogonial stem cells.

INVOLVEMENT OF PURINERGIC SIGNALING AND LYMPHOID ORGANS IN THE BENEFICIAL EFFECTS OF AEROBIC TRAINING IN ASTHMA

PURPOSE: Asthma is a chronic airway inflammatory disease affecting more than 300 million people around the world. Purinergic signaling via purinergic receptors (mainly P2X7, P2Y2 and P2Y6) are thought play a key role in asthma pathogenesis and severity. High intensity aerobic exercise is known to trigger asthma attacks, while low to moderate intensity training reduces inflammation and improves asthma control. Therefore, this study investigated whether low intensity aerobic exercise reduces asthma phenotype by modulation of purinergic signaling. METHODS: Aerobic exercise (AE) was performed in a treadmill at low intensity, 5x/week, 1h/session, for 4 weeks, beginning 2 weeks after HDM administration. HDM (dermatophagoides pteronyssinus; 100mg/mouse) was administered 3x/week, for 6 weeks. RESULTS: The results demonstrated that AE reduced adenosine triphosphate (ATP) accumulation (p<0.001), IL-1beta, IL-4, IL-5, CXCL1/KC, IL-13, IL-17, IL-23, IL-33 and TNF-alpha (p<0.001), while increased IL-1ra, IL-2, IL-10 and IL-12p40 in bronchoalveolar lavage (BAL). Total number of leukocytes, eosinophils, lymphocytes and neutrophils in BAL and the number of eosinophils, neutrophils and lymphocytes in the airway wall (p<0.01) were reduced by AE. Airway remodeling (collagen, elastin, smooth muscle and mucus) were reduced by AE (p<0.01). TGF-beta, IGF-1 and VEGF levels was reduced by AE (p<0.001). Lung mechanics (Resistance, Elastance, GTIS, HTIS, RAW) and airway hyperresponsiveness (AHR) to methacholine was ameliorated by AE (p<0.01). IL-4, IL-5 and IL-13 production by re-stimulated mediastinal lymph nodes, splenocytes and bone marrow cells was also reduced by AE. The expression of P2X7, P2Y2 and P2Y6 by peribronchial leukocytes (p<0.01) and also by airway epithelial cells (p<0.01) were reduced by AE. CONCLUSIONS: Low intensity aerobic training reduces asthma phenotype by inhibiting purinergic signaling and lymphoid organs hyperactivation.

Acute Cardiopulmonary And Hemodynamic Responses To Exercise With Blood-flow Restriction In Heart Failure Patients

Muscle training with blood flow restriction (BFR) can induce significant increases in muscle strength and mass, while BFR during low intensity aerobic training increases aerobic capacity more than the usual aerobic exercise at the same intensity. However, little is known about the safety and feasibility of BFR training in patients with chronic heart failure (CHF). PURPOSE: This study compared hemodynamic and cardiopulmonary responses during low intensity aerobic exercise with and without BFR in CHF patients. METHODS: Nine CHF patients, 7 males and 2 females (age: 55.6±12.2 years, height: 175.0±10.3 cm, body mass: 89.6±29.1 kg, VO2peak: 22.4±5.04 ml/kg/min, ejection fraction: 36±6%, NYHA: I-II) volunteered to participate in this crossover study. Each participant performed the same aerobic exercise protocol, i.e. a 20-minute cycling bout at 65% of VO2peak, with (BFR) and without BFR (control) in random order, using a cycle ergometer. In the BFR condition, an occlusion cuff was used to regulate the occlusion pressure applied to both limbs that was proportional to thigh circumference. Mean oxygen uptake (VO2) during the 20 minutes exercise, VO2 recovery during the first minute of recovery (VO2/t slope), heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure at 6 min, 12 min and 18 min of exercise, fatigue and dyspnea perception were assessed. ANOVA or paired t-test was used for statistics and data are presented as mean±SD. RESULTS: Mean VO2 during exercise was higher in BFR compared to control (70.6±9.8% vs 64.0±10.1%, p=0.003), while VO2/t slope was higher in control (0.79±0.23 vs 0.53±0.11, p= 0.008). HR was higher during the BFR exercise (94±15 vs 88±15, 97±20 vs 90±19, 96±10 vs 84±9 at 6, 12 and 18 min, respectively; p<0.05), whereas SBP and DBP did not differ between the two conditions at any time point (p>0.05). Fatigue (12.4±2.7 vs 8.8±1.7, p=0.002) and dyspnea (11.5±2.5 vs 9.2±1.9, p=0.03) perception were significantly higher in BFR compared to control. CONCLUSIONS: To our knowledge, this is the first study examined BFR exercise in CHF patients, revealing specific cardiopulmonary and hemodynamic responses and suggesting that this exercise strategy is safe and feasible in those patients. More studies are needed to verify and further characterize the acute and chronic effects of BFR training in CHF patients.

The effects of Aerobic exercise intensity participation training on body composition, health related fitness and quality of life in elderly women

Purpose The purpose of this study was to investigate the effects of aerobic exercise intensity on body composition, health related fitness, and quality of life in elderly women. Methods 48 elderly women over 65 years of age without physical and mental problems were assigned to four groups: control group, low intensity, moderate intensity, and high intensity aerobic training group. The aerobic exercise group applied a heart rate reserve (HRR) to low-intensity group (HRR 40-55%), moderate intensity group (HRR 55-70%), high intensity group (HRR&gt; 70%) for 12 weeks, 3 times a week for 20 minutes a day. Subjects of the control group were to maintain their usual lifestyles during the same intervention period. Body composition, health related fitness, and quality of life were measured and analyzed using repeated two-way ANOVA. Results The main results obtained in this study are as follows. 1) There was a significant decrease in sitting forward bending in the low intensity group and a significant increase in EQ-VAS. 2) There was a significant decrease in body weight, BMI, and 6 minutes walking in the moderate intensity group, and a significant increase in grip strength and EQ-VAS. 3) The high intensity group showed a significant decrease in weight, BMI, waist circumference, sitting forward bending, and 6 minutes walking, and a significant increase in grip strength, sit and stand, functional reach, and VO2max. On the other hand, there was no significant change in all variables in the control group. Conclusions In conclusion, aerobic training was found to be effective for body composition, health related fitness and quality of life in elderly women. In particular, it can be concluded that high intensity aerobic training is effective for health related fitness, and low and moderate intensity aerobic exercise is effective for improving quality of life.

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.

The effect of low-intensity aerobic training on cognitive functions of severely deconditioned subacute and chronic stroke patients: a randomized, controlled pilot study.

Our objective was to investigate the impact of low-intensity aerobic training on cognitive functions in severely deconditioned subacute and chronic stroke patients. For this purpose, a randomized, controlled pilot study was designed involving subacute and chronic stroke patients. Thirty-seven eligible patients participated in the 4-week-long randomized, controlled pilot study. Patients were randomized into study group and control group and both groups participated in conventional physiotherapy included occupational therapy. Only the study group's patients participated in a low-intensity aerobic training by cycle ergometer. Cognitive evaluations (Functional Independence Measure Cognitive part - FIM-cog; Coding and Symbol Search tasks of the Processing Speed index and Digit Span task of Working Memory index of Wechsler Adult Intelligence Scale-Fourth Edition) were performed before and after the programme. In-group analysis showed a significant improvement in study group patients regarding Coding subtest of Processing Speed domain (P = 0.003). Symbol Search subtest of Processing Speed showed significant improvements in both groups by the end of the programme (study group, P = 0.041; control group, P = 0.006). There were no significant changes in the FIM-cog and Digit Span task. The intergroup analysis did not find significant difference between the two groups. It was concluded that even the low-intensity aerobic training may improve special domains of cognitive function after stroke. Further studies are needed to confirm the impact of low-intensity aerobic training on cognitive functions.

Investigation the effect of low-intensity aerobic training for 10 weeks along with blood flow restriction on amount of protein BDNF in soleus and EDL muscles as well as the sciatic nerve in aged male rats

چکیدههدف: هدف از مطالعه حاضر بررسی تأثیر 10 هفته تمرین هوازی کم شدت همراه با محدودیت جریان خون بر میزان پروتئین فاکتور نروتروفیک مشتق شده از مغز(BDNF) در عضلات سلئوس و EDL و همچنین عصب سیاتیک موشهای صحرایی نر سالمند بود.روش تحقیق: 60 موش صحرایی نر کهنسال(23-24 ماه) نژاد ویستار، وزن بین 355 تا 481 گرم بودند که به 6 گروه تصادفی، گروه جراحی(BFR)، گروه جراحی ورزش(BFR+Ex)، گروه شم( Sham)، گروه شم ورزش(Sham+Ex)، کنترل( Ctl) و گروه کنترل ورزش(Ex) تقسیم شدند. گروه ها بعد از 10 هفته تمرین سبک هوازی (15متر/دقیقه) به مدت 1 ساعت، 5 جلسه در هفته تمرین کردند و 48 ساعت بعد از آخرین جلسه تمرین، قربانی شدند. نمونه عضلات و عصب سیاتیک بلافاصله جدا در نیتروژن جامد گذاشته و در دمای 80- درجه حفظ شدند. نمونه ها پروتئینی توسط روش وسترن بلات مورد سنجش قرار گرفتند. در این مطالعه تجزیه و تحلیل داده های تحقیق با استفاده از نرم افزار آماری SPSSورژن 18انجام شد. توزیع طبیعی داده ها به وسیله آزمون شاپیرو - ویلک مشخص شد. برای آزمون فرضیه های تحقیق از تحلیل واریانس یک سویه استفاده گردید. همچنین جهت تفاوت معنی داری بین گروه های مختلف از آزمون تعقیبی توکی استفاده شد. سطح معناداری 0.05 P≤ در نظر گرفته شد.نتایج: نتایج نشان داد که پروتئین BDNF در عضله EDL درگروه BFR+Ex تنها با گروه های Ctl و Sh کاهش معنی دار(0.05P˂) داشت. همچنین در عضله سلئوس گروه BFR+Ex با تمامی گروه ها کاهش معنی داری(با گروه های Ctl ، Sh و BFR 0.00 =p و Ex و Sh+Ex 0.03 p˂ ) داشت. علاوه بر این گرو ه های Ex، Sh+Ex نیز نسبت به گروه Ctl و Sh (0.00= p) کاهش معنی داری داشتند. از طرفی در عصب سیاتیک گروه BFR+Ex نسبت به همه ی گروه ها افزایش معنی داری(0.00= p) را نشان داد. نتیجه گیری: این مطالعه نشان داد که این نوع تمرینات می تواند بر میزان پروتئین BDNF عضلات تند و کند انقباض تأثیر گذاشته و موجب جریان برگشتی از عضله به عصب شود. همچنین افزایش پروتئین BDNF بعد از این تمرینات در عصب سیاتیک مشاهده شد. و نشان داد که BFR+Ex به عنوان یک روش تمرینی می تواند روی عصب و عضله تأثیر مثبت بگذارد.کلمات کلیدی: تمرین استقامتی-فاکتورهای نروتروفیک- کاهش جریان خون- دوران پیری

PO-053 Plasma Metabolic Profiles of Elite Rowers Response to the Early Phase of Altitude Training Based on LC-MS

Objective When arriving at altitude, because of the dry air, strong ultraviolet and especially the low oxygen et.al., athletes who living on the plain always exhibited kinds of stress reactions such as hyperventilation, tachycardia, dizziness, sleep-disorder, gastrointestinal disturbance and cognitive impairment in the early phase. Except these stress reactions, some studies reported the carbohydrate and lipid metabolism show significant change. Acute exposure to hypoxia could strengthen the glycolysis and suppress hepatic gluconeogenesis. The expression of some genes involved in lipid oxidation was down-regulated. However, it’s also found the increased activity of some enzymes took part in aerobic metabolism in muscle after long term acclimatization to altitude. These inconsistent conclusions make us confusion. Train load is an important factor influence the stress reactions which isn’t like as altitude travel for normal people. What would happen in the body of athletes when altitude training? We still know very little. Metabonomic give us a new tool to understand the whole map of body’s reaction to altitude training. In this pilot study, we aimed to explore the plasma profiles changes of elite rowers in the early two-weeks training at 2300m plateau using metabolic tool based on LC-MS.&#x0D; Methods Sixteen male elite rowers(age 25.56±3.44y, height 189.06±5.37cm, weight 82.81±12.25kg, training years 10.31±2.52y) from China National team took part in this research. This altitude training camp was organized in the preparation period of a new season. It lasted six weeks. The acute phase (AP) which was the first three days after arriving at 2300m altitude base was composed by regenerative training and low-intensity aerobic training sessions. During the next ten days (chronic phase, CP), the intensity of most sessions including three low-weight resistance training sets were low to middle aerobic. After resting half day, 5 ml venous blood was collected into heparin anticoagulant tubes and then centrifuged at 8000rpm in 4℃ lasting 15 minutes to separate plasma in the 4th day and 14th morning. Plasma was stored in -80℃ to measure metabolic profile by LC-MS. The data was performed feature extraction and preprocessed with Compound Discoverer 2.0 software (Thermo), and then normalized and edited into two-dimensional data matrix by excel 2010 software, including Retention time(RT), Compound Molecular Weight (compMW), Observations(samples) and peak intensity. The feature data after editing were performed Multivariate Analysis (MVA) using SIMCA-P software (Umetrics AB, Umea, Sweden).&#x0D; Results Compared with pre-altitude, 26 and 30 features at (ESI+) ion mode, 57 and 49 features at (ESI-) ion mode were found in the AP and CP respectively. Compared AP with CP, there were 46 features at (ESI+) ion mode and 67 features at (ESI-) ion mode. In AP, plasma benzamide and indole-3-acetaldehyde increased 35.16 fold and 16.54 fold respectively. Plasma phenethylamine, phenol, indole, piperidine, leucine, 4-chlorbenzoic acid and benzoic acid increased 4.55 to 8.22 fold compared with pre-altitude. Top three decreased features were dibutyl sebacate, arbinosylhypoxanthine and cholesterol hydrogen sulfate which decreased 1.76 to 3.85 fold in AP. After a longer adaption, in the 14th day of altitude training, plasma benzamide, indole-3-acetaldehyde, phenethylamine, indole, 4-chlorbenzoic acid and benzoic acid still increased but the amplitude reduced compared with the 4th day. Ingenuity Pathways Analysis (IPA) suggested that the top 5 canonical pathways were tyrosine biosynthesis Ⅳ, phenylalanine degradationⅠ, protein kinase A signaling, tRNA charging and phenylalanine degradation Ⅳ in AP. In CP, the top 5 canonical pathways were tRNA charging, urate biosynthesis, tryptophan degradation Ⅹ, guanosine nucleotides degradation Ⅲ and adenosine nucleotides degradationⅡ.&#x0D; Conclusions In this pilot study, we found 83 and 79 plasma feature in acute and chronic phase respectively. Considering the sharp elevation, plasma benzamide and indole-3-acetaldehyde which involved in the regulation of energy metabolism of brain may be the sensitive makers in acute adaption to altitude for athletes. As the extension of time, the increased amplitude came down in the 14th day. It suggested that the energy metabolism of brain may take significant change. Central nerve system should be paid more attention during altitude training especially in the early phase.

Short-term effect of low intensity forced aerob exercise added to conventional physiotherapy on cognitive functions and fitness after stroke: A randomized controlled pilot study

Emerging experimental and clinical findings suggest that aerob forced exercise may potentially have positive benefits on cognitive functions. The purpose of our pilot study was to assess the effect of low intensity aerobic exercise on cognitive functions in individuals with chronic stroke. Thirty-five chronic, ambulatory stroke patients aged between 33 and 76 years old completed the 4-week program, 90 min session/day in every workday. They were randomized into two groups: study group (SG, n = 19, median age 59/40–76/) years and control group (CG, n = 16 median age 62/33–69/) years. Both groups participated in conventional physiotherapy but only SG performed aerob exercise training with bicycles (30 min/day). Exercise intensity progressed from 30 to 40% of heart rate reserve defined by ergospiromety. Functional Independence Measure (FIM-cognitive) and Wechsler Adult Intelligence Scale processing speed (symbol search, coding) and working memory (digit span forward, backward and sequencing) subtests were recorded at baseline and 4 weeks later. Maximum oxygen intake (VO 2max ) was measured at baseline and 4 weeks later. Inside group analysis showed a significant improvement in both groups in cognitive-FIM ( P = 0.008). A significant change was not found in working memory (digit span) subtest ( P = 0.16) in either of the groups. In processing speed subtest (coding) a significant improvement was only measured in SG ( P = 0.003) while in a symbol search test an improvement was found in both groups (SG: P = 0.041, CG: P = 0.006). There were not inter-group differences in any subtest (all P = 0.201) and in VO 2max ( P = 0.8). Any significant improvement in VO 2max was not found in either of the groups ( P = 0.7). The results suggested that low intensity aerobic exercise training integrated into conventional stroke rehabilitation program had effects on the selected measures of cognitive functions, nevertheless the VO 2 max remained unchanged. Further studies are needed to get evidence with sufficient power.