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1.
Although angiogenetic therapy using recombinant growth factors holds much hope for the treatment of ischaemic diseases, there are still many unanswered questions, including the method of administration, the correct dose of these factors, and the duration of the therapeutic approach. Exercise has also been suggested to induce neovascularizaiton in muscles. We evaluated the angiogenetic effects of the intramuscular administration of basic-fibroblast growth factor (b-FGF) and acidic-fibroblast growth factor (a-FGF) in rat heart, compared with rats who exercised daily. In conclusion, both the intramuscular administration of b-FGF and exercise increased significantly angiogenesis in the heart in contrast to the intramuscular administration of a-FGF, which was ineffective.  相似文献   

2.
Abstract

This study examined the influence of holding a bag with one hand on the center of foot pressure (COP) and the electromyographic responses in lower leg muscles. Thirteen healthy male adults participated in this study to keep an upright posture while holding a load with the dominant hand with four bag weight conditions (0%, 15%, 30%, and 45% of maximal voluntary contraction (MVC) of the jerk strength). Integrated Electromyography (iEMG) and mean power frequency (MPF) of EMG were calculated to estimate the degree of muscle activity and fatigue in the tibialis anterior and soleus that are involved in ankle joint control. Body sway was evaluated by the mean position of left-right (X) and front-back (Y) axis sway and the following 4 body sway factors; unit time sway factor (F1), front-back sway factor (F2), left-right sway factor (F3), high frequency band power spectrum factor (F4). When holding a bag at 45% MVC or more of the jerk strength with a single hand for one minute, muscle activity in the lower leg on the side of the bag increased markedly, and muscle fatigue was induced in the antigravity muscles of both legs. As a result, anteroposterior sway increased to a short, quick sway.  相似文献   

3.
BackgroundPromoting cardiac lymphangiogenesis exerts beneficial effects for the heart. Exercise can induce physiological cardiac growth with cardiomyocyte hypertrophy and increased proliferation markers in cardiomyocytes. However, it remains unclear whether and how lymphangiogenesis contributes to exercise-induced physiological cardiac growth. We aimed to investigate the role and mechanism of lymphangiogenesis in exercise-induced physiological cardiac growth.MethodsAdult C57BL6/J mice were subjected to 3 weeks of swimming exercise to induce physiological cardiac growth. Oral treatment with vascular endothelial growth factor receptor 3 (VEGFR3) inhibitor SAR131675 was used to investigate whether cardiac lymphangiogenesis was required for exercise-induced physiological cardiac growth by VEGFR3 activation. Furthermore, human dermal lymphatic endothelial cell (LEC)-conditioned medium was collected to culture isolated neonatal rat cardiomyocytes to determine whether and how LECs could influence cardiomyocyte proliferation and hypertrophy.ResultsSwimming exercise induced physiological cardiac growth accompanied by a remarkable increase of cardiac lymphangiogenesis as evidenced by increased density of lymphatic vessel endothelial hyaluronic acid receptor 1–positive lymphatic vessels in the heart and upregulated LYVE-1 and Podoplanin expressions levels. VEGFR3 was upregulated in the exercised heart, while VEGFR3 inhibitor SAR131675 attenuated exercise-induced physiological cardiac growth as evidenced by blunted myocardial hypertrophy and reduced proliferation marker Ki67 in cardiomyocytes, which was correlated with reduced lymphatic vessel density and downregulated LYVE-1 and Podoplanin in the heart upon exercise. Furthermore, LEC-conditioned medium promoted both hypertrophy and proliferation of cardiomyocytes and contained higher levels of insulin-like growth factor-1 and the extracellular protein Reelin, while LEC-conditioned medium from LECs treated with SAR131675 blocked these effects. Functional rescue assays further demonstrated that protein kinase B (AKT) activation, as well as reduced CCAAT enhancer-binding protein beta (C/EBPβ) and increased CBP/p300-interacting transactivators with E (glutamic acid)/D (aspartic acid)–rich-carboxylterminal domain 4 (CITED4), contributed to the promotive effect of LEC-conditioned medium on cardiomyocyte hypertrophy and proliferation.ConclusionOur findings reveal that cardiac lymphangiogenesis is required for exercise-induced physiological cardiac growth by VEGFR3 activation, and they indicate that LEC-conditioned medium promotes both physiological hypertrophy and proliferation of cardiomyocytes through AKT activation and the C/EBPβ-CITED4 axis. These results highlight the essential roles of cardiac lymphangiogenesis in exercise-induced physiological cardiac growth.  相似文献   

4.
Abstract

Acute muscle belly injuries to the semitendinosus, semimembranosus and biceps femoris (the ‘hamstring’ muscles) remain a common problem in the sporting population. Physiotherapy-led rehabilitation remains the mainstay of treatment, and the physician's input is often minimal. Anecdotally, many different topical, oral and injectable therapies are used around the world in an effort to accelerate the healing of these injuries and to prevent their recurrence. This article reviews the evidence available to support some of the most commonly used medical therapies and the pathophysiological basis for their use. It also presents the evidence behind some of the more promising future treatments for muscle injury, including stem cell therapy, growth factor delivery and potential novel uses of current medication not traditionally used in the musculoskeletal setting.  相似文献   

5.
Abstract

The aim of the present study was to determine whether 4 months of intensified training would result in modified plasma insulin-like growth factor I (IGF-I), insulin-like growth factor binding protein 1 (IGFBP-1) or IGFBP-3 in eight competitive cyclists and eight sedentary individuals and to define the relationships of these factors with glucose disposal. Insulin sensitivity and glucose effectiveness — that is, the fractional disappearance of glucose independent of any change in insulinaemia — were measured with the minimal model (mathematical analysis of frequently sampled intravenous glucose tolerance test). Both glucose effectiveness and insulin sensitivity were higher in the cyclists than in the sedentary individuals, but did not increase further with training. IGF-I was higher in the cyclists than in the sedentary group only after training (P<0.05). Plasma IGFBP-1 and IGFBP-3 increased after training (38 and 20%, respectively; P<0.05) in the cyclists and were higher than in the sedentary individuals (P<0.05). IGF-I was negatively correlated with insulin sensitivity before and after training (r=?0.66 and ?0.67, respectively; P<0.05) and IGFBP-1 was negatively correlated with glucose effectiveness before and after training (r=?0.68 and ?0.77, respectively; P<0.05). Our results show that strenuous endurance training improves the somatotrope axis (growth hormone—IGF) and that IGFBP-1 may be involved in glucose homeostasis, possibly by limiting the exercise-induced increase in glucose disposal, in competitive cyclists.  相似文献   

6.
Purpose

Physical activity participation in physical education is compromised when students nonsuit. We investigated: (a) reasons for nonsuiting/support of policy change and whether they differed by gender, ethnicity, or grade; and (b) the likelihood of nonsuiting based on the same demographics.

Method

Participants (N = 627) were 6th and 7th graders attending 1 urban middle school located in San Diego, CA. Students completed a questionnaire composed of 4 demographic items, level of agreement with 15 reasons for nonsuiting, and level of support of 6 proposed policy changes. Exploratory and confirmatory factor analyses were used to classify reasons for nonsuiting items and policy change items. Demographic differences among resultant factor scores and individual items were analyzed using t tests. Associations between factors/items and nonsuit frequency and demographics were analyzed using multinomial logistic regression.

Results

Girls, Latinos, and 7th graders were more likely habitual nonsuits ( ≥ 4 nonsuits) compared with their respective counterparts. Statistically significant factor scores (reasons for nonsuiting; emotional excuses, utilitarian excuses) were higher among habitual nonsuits but were not different based on gender, grade, and ethnicity. Seventh graders and girls had statistically significantly higher policy change factor scores compared with their respective counterparts.

Conclusion

Acting on student input toward reformulating suiting-out policy as well as addressing emotional excuse reasons, which are primarily under teacher control, may result in lower incidence of habitual nonsuiting.  相似文献   

7.
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8.
BackgroudBlood flow restriction (BFR) with low-intensity resistance training has been shown to result in hypertrophy of skeletal muscle. In this study, we tested the hypothesis that BFR during the rest periods between acute, high-intensity resistance exercise sessions (70% of 1 repetition maximum, 7 sets with 10 repetitions) enhances the effects of the resistance training.MethodsA total of 7 healthy young men performed squats, and between sets BFR was carried out on one leg while the other leg served as a control. Because BFR was applied during rest periods, even severe occlusion pressure (approximately 230 mmHg), which almost completely blocked blood flow, was well-tolerated by the participants. Five muscle-specific microRNAs were measured from the biopsy samples, which were taken 2 h after the acute training.ResultsDoppler data showed that the pattern of blood flow recovery changed significantly between the first and last BFR. microRNA-206 levels significantly decreased in the BFR leg compared to the control. The mRNA levels of RAC-β serine/threonine-protein kinase v22, nuclear respiratory factor 1, vascular endothelial growth factor, lupus Ku autoantigen protein p70 genes (p < 0.05), and paired box 7 (p < 0.01) increased in the BFR leg. The protein levels of paired box 7, nuclear respiratory factor 1, and peroxisome proliferator-activated receptor γ coactivator 1α did not differ between the BFR leg and the control leg.ConclusionBFR, during the rest periods of high-load resistance training, could lead to mRNA elevation of those proteins that regulate angiogenesis, mitochondrial biogenesis, and muscle hypertrophy and repair. However, BFR also can cause DNA damage, judging from the increase in mRNA levels of lupus Ku autoantigen protein p70.  相似文献   

9.
BackgroundEmerging research supports the idea that exercise positively affects neurodevelopment. However, the mechanisms linking exercise with brain health are largely unknown. We aimed to investigate the effect of exercise on (a) blood biomarkers selected based on previous evidence (brain-derived neurotrophic factor, β-hydroxybutyrate (BHB), cathepsin B (CTSB), kynurenine, fibroblast growth factor 21 (FGF21), soluble vascular cell adhesion molecule-1 (sVCAM-1)); and (b) a panel of 92 neurology-related proteins (discovery analysis). We also investigated whether changes in these biomarkers mediate the effects of exercise on brain health (hippocampal structure and function, cognitive performance, and mental health).MethodsWe randomized 81 overweight/obese children (10.1 ± 1.1 years, 41% girls) into 2 groups: either 20 weeks of aerobic plus resistance exercise or control. Candidate biomarkers were assessed using enzyme-linked immunosorbent assay (ELISA) for kynurenine, FGF21, and CTSB; colorimetry for β-hydroxybutyrate; and XMap for brain-derived neurotrophic factor and soluble vascular cell adhesion molecule-1. The 92 neurology-related proteins were analyzed by an antibody-based proteomic analysis.ResultsOur intervention had no significant effect on candidate biomarkers (all p > 0.05). In the discovery analysis, a reduction in circulating macrophage scavenger receptor type-I was observed (standardized differences between groups = –0.3, p = 0.001). This effect was validated using ELISA methods (standardized difference = –0.3, p = 0.01). None of the biomarkers mediated the effects of exercise on brain health.ConclusionsOur study does not support a chronic effect of exercise on candidate biomarkers. We observed that while chronic exercise reduced the levels of macrophage scavenger receptor type-I, it did not mediate the effects of exercise on brain health. Future studies should explore the implications of this novel biomarker for overall health.  相似文献   

10.
Abstract

This study investigated whether exercise-induced muscle damage (EIMD) resulted in changes to whole-body substrate utilisation during exercise performed during the subsequent 48 hours. Eight males (31±6 years) performed 30 minutes of bench-stepping exercise. One leg performed eccentric contractions (Ecc) by lowering the body whilst the control leg performed concentric contractions (Con) by raising the body. On the two days following bench-stepping exercise participants performed measures of muscle function on an isokinetic dynamometer and undertook a bout of one leg cycling exercise, at two differing workloads, with the first workload (WL1) at 1.5±0.25 W/kg and the second workload (WL2) at 1.8±0.25 W/kg with each leg. Expired respiratory gases were collected during cycling to estimate whole body substrate utilisation. There were significant decrements in measures of muscular performance (isometric force, concentric and eccentric torque) and increased perception of soreness in Ecc compared with Con (P < 0.05). The effect of the Ecc treatment on substrate utilisation during one-legged cycling revealed a significant trial×time interaction with higher rates of CHO oxidation in the Ecc condition compared with Con that were further increased 48 hours later (P = 0.02). A significant treatment×time×effort interaction (P < 0.01) indicated the effect of the treatment altered as workload increased with higher rates of CHO oxidation occurring in WL2. This is consistent with greater reliance upon muscle glycogen. Suggesting that in EIMD, reductions in strength and increased feelings of soreness can be associated with greater reliance upon intramuscular CHO oxidation, than lipid, during subsequent concentric work.  相似文献   

11.
Abstract

The overall purpose of this two-part study was to examine factors that influenced fatigue status in university level swimmers. Participants were 25 swimmers (14 male, 11 female) from one university swim team. A mixed methods approach was used. Quantitative data were collected using an orthostatic heart rate test and self-report questionnaire at multiple time points throughout a competitive season. Qualitative data were collected via focus groups conducted at the end of the season. Analysis of the quantitative data indicated high levels of accumulated physiological and psychological fatigue that improved with increased recovery. Specifically, heart rate indices, form, feeling, and energy level improved during taper periods and worsened during and immediately after intensive training blocks. Analysis of the qualitative data revealed that one factor (flexible structure of training programme) had a positive influence on athletes’ fatigue while two factors (teammate expectations and balancing school, work, and sleep) had a negative influence on athletes’ fatigue.  相似文献   

12.
ObjectiveIn this review, we critically evaluate studies directly comparing the effects of plyometric vs. resistance training on skeletal muscle hypertrophy.MethodsWe conducted electronic searches of PubMed/MEDLINE, Scopus, SPORTDiscus, and Web of Science to find studies that explored the effects of plyometric vs. resistance training on muscle hypertrophy.ResultsEight relevant studies were included in the review. Six studies compared the effects of plyometric vs. resistance training on muscle hypertrophy, while 2 studies explored the effects of combining plyometric and resistance training vs. isolated resistance training on acute anabolic signaling or muscle hypertrophy. Based on the results of these studies, we conclude that plyometric and resistance training may produce similar effects on whole muscle hypertrophy for the muscle groups of the lower extremities. Therefore, it seems that plyometric training has a greater potential for inducing increases in muscle size than previously thought. Despite the findings observed at the whole muscle level, the evidence for the effects of plyometric training on hypertrophy on the muscle fiber level is currently limited for drawing inferences. Compared to isolated resistance training, combining plyometric and resistance exercise does not seem to produce additive effects on anabolic signaling or muscle growth; however, this area requires future study. The limitations of the current body of evidence are that the findings are specific to (a) musculature of the lower extremities, (b) short-term training interventions that lasted up to 12 weeks, and (c) previously untrained or recreationally active participants.ConclusionThis review highlights that plyometric and resistance training interventions may produce similar effects on whole muscle hypertrophy, at least for the muscle groups of the lower extremities, in untrained and recreationally trained individuals, and over short-term (i.e., ≤12 weeks) intervention periods.  相似文献   

13.
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14.
BackgroundRegular exercise is beneficial for adults with cardiovascular disease (CVD) and CVD risk factors. Tai Ji Quan is popular among older adults and may offer additional exercise options. The present article aims to review the scientific literature published within the past decade on Tai Ji Quan as an exercise modality to prevent and manage CVD.MethodsAn electronic literature search of four databases (PubMed, CINAHL, PsycINFO, and AMED) was conducted from April 2003 through March 2013. Studies that examined Tai Ji Quan, were published in English, and specified a target study population of participants with a known CVD condition (e.g., coronary artery disease, chronic heart failure, or stroke) or studies conducted among participants with a CVD risk factor (e.g., hypertension, dyslipidemia, or impaired glucose metabolism) were included.ResultsA total of 20 studies met the inclusion criteria: 11 randomized clinical trials, seven quasi-experimental studies and two cross-sectional studies. The effect of Tai Ji Quan was examined on more than 20 different study variables among persons with coronary artery disease (n = 5 studies), chronic heart failure (n = 5 studies), stroke (n = 4 studies), and CVD risk factors (n = 6 studies). These studies were conducted primarily in Asia (n = 9, 45%) or the United States (n = 8, 40%). Overall, participants enrolled in Tai Ji Quan had better outcomes, though mixed results were reported.ConclusionCollectively, these studies indicate that Tai Ji Quan is a safe form of exercise to prevent and manage CVD. Further research is needed with more rigorous study designs, larger sample sizes, adequate Tai Ji Quan exercise doses, and carefully chosen outcome measures that assess the mechanisms as well as the effects of Tai Ji Quan, before widespread recommendations can be made.  相似文献   

15.
BackgroundThis prospective study explored the effects of endurance running (ER) in minimal versus standard running shoes on the foot's superficial layer intrinsic muscles and the function of the longitudinal arch. Our hypothesis was that running in minimal shoes would cause hypertrophy in these muscles and lead to higher, stronger, stiffer arches.MethodsThe hypothesis was tested using a sample of 33 healthy runners randomized into two groups, a control group shod in traditional running footwear and an experimental group shod in minimal support footwear, whose feet were scanned in an MRI before and after a 12-week training regime. Running kinematics as well as arch stiffness and height were also assessed before and after the treatment period.ResultsAnalysis of anatomical cross-sectional areas and muscle volumes indicate that the flexor digitorum brevis muscle became larger in both groups by 11% and 21%, respectively, but only the minimally shod runners had significant areal and volumetric increases of the abductor digiti minimi of 18% and 22%, respectively, and significantly increased longitudinal arch stiffness (60%).ConclusionThese results suggest that endurance running in minimal support footwear with 4 mm offset or less makes greater use of the spring-like function of the longitudinal arch, thus leading to greater demands on the intrinsic muscles that support the arch, thereby strengthening the foot.  相似文献   

16.
Abstract

The data for 40 variables were obtained from 81 Purdue University faculty sons between 10 and 12 years of age inclusive. Among the 40 variables, 680 correlation coefficients were obtained. Factor analysis was used to identify the factors which could explain the items measuring body composition and motor aptitude. As a result, eight factors were isolated and given names. The factors underlying the 40 variables seemed to permit the following names: growth and maturity factor, “body fitness” factor, body balance on object factor, coordination of the lower extremities factor, general kinesthetic sense factor, general static balance factor, directionality factor, and laterality factor. Observing the factor loadings in Factor I, it may be concluded that the measurement of lean body weight by liquid scintillation counting technique is significant in the assessment of growth and maturity in preadolescent boys. Furthermore, in the assessment of “body fitness” pertaining to preadolescent boys, it is revealed that the percent lean body weight is the most important item as indicated by the value of factor loading presented in Factor II.  相似文献   

17.
PurposeThe purpose of this study was to determine which intensities, patterns, and types of 24-h movement behaviors are most strongly associated with cardiometabolic risk factors among children.MethodsA total of 369 children aged 10–13 years were studied. Participants wore an Actical accelerometer and a Garmin Forerunner 220 Global Positioning System logger and completed an activity and sleep log for 7 days. Data from these instruments were combined to estimate average minute per day spent in 14 intensities, 11 types, and 14 patterns of movement. Body mass index, resting heart rate, and systolic blood pressure values were combined to create a cardiometabolic risk factor score. Partial least squares regression analysis was used to examine associations between the 39 movement behavior characteristics and the cardiometabolic risk factor score. The variable importance in projection (VIP) values were used to determine and rank important movement behavior characteristics. There was evidence of interaction by biological maturity, and the analyses were conducted separately in the 50% least mature and 50% most mature participants.ResultsFor the least biologically mature participants, fifteen of the 39 movement behavior characteristics had important VIP value scores; eight of these reflected movement intensities (particularly moderate and vigorous intensities), six reflected movement patterns, and one reflected a movement type. For the most mature participants, thirteen of the 39 movement behavior characteristics had important VIP value scores, with five reflecting intensities (particularly moderate and vigorous intensities), five reflecting patterns, and three reflecting types of movement.ConclusionMore than 12 movement behavior characteristics were associated with cardiometabolic risk factors within both the most and least mature participants. Movement intensities within the moderate and vigorous intensity ranges were the most consistent correlates of these risk factors.  相似文献   

18.
目的:探究肌肉能量技术结合肌内效贴扎治疗肩周炎是否优于常规康复治疗手段。方法:收集金秋医院康复科门诊进行治疗的40名肩周炎患者,排除其他干扰因素后,将其随机分为实验组和对照组,每组20人,实验组在常规治疗肩周炎基础上采取肌肉能量技术和肌内效贴扎结合治疗,对照组进行常规治疗。结果:8周治疗后,两组患者主动关节活动度(AROM)、视觉类比评分(VAPS)等相关评分均明显优于治疗前(P<0.05),且实验组各项评分更优于对照组(P<0.05)。结论:在常规康复治疗的基础上应用肌肉能量技术与肌内效贴扎相结合的治疗措施能更有效地改善肩周炎患者的功能障碍,减轻患者痛苦,加快患者康复进程。  相似文献   

19.
Abstract

This study was conducted for the purpose of determining the relationship between specific factors of personality adjustment and levels of motor achievement in a select group of junior and senior high school boys. Pertinent scales from the 16 Personality Factor Questionnaire and the Guilford Zimmerman Temperament Survey were administered to 154 subjects for the purpose of determining existing personality characteristics. The motor achievement data were collected from administration of the McCloy General Motor Ability and Motor Capacity Test. The data were statistically analyzed through the use of the Pearson product-moment correlation technique, the t test, and the multiple regression technique. The study concluded that, (a) individual group dependance was a factor in extent of exhibited motor achievement and, (b) that levels of motor achievement were predictable with the use of grouped measured personality characteristics.  相似文献   

20.
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