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51.
Nobuo Takeshima Kiyoji Tanaka Fumio Kobayashi Takemasa Watanabe Takashi Kato 《European journal of applied physiology》1993,67(2):138-143
Summary In this study we attempted to determine the effects of exercise training at the intensity corresponding to lactate threshold (Thla
–) on various health-related variables in sedentary but apparently healthy elderly subjects. Six men and five women volunteers [mean age 68.9 (SD 3.4) years] performed supervised endurance-type training on stationary cycle ergometers for 30 min and recreational activities for 30 min, 3 days a week for 12 weeks. Four men and four women served as the control group [68.8 (SD 4.4) years]. As a result of the training programme, statistically significant increases in maximal oxygen consumption (10%), oxygen consumption at Thla
–(18%), distance covered in 12-min walk, side step, and leg extensor power were found in the training group, while no changes occurred in the control group. The changes in serum cholesterol and triglyceride concentrations from the pre- to post-training period were statistically significant. High-density lipoprotein cholesterol remained unchanged, and low-density lipoprotein cholesterol tended to decrease following the training programme. These data would indicate that exercise training at the intensity corresponding to Thla
–may have favourable effects on overall physical fitness and some serum lipid variables in older individuals. 相似文献
52.
E. JANSSON M. ESBJ
RNSSON I. HOLM I. JACOBS 《Acta physiologica (Oxford, England)》1990,140(3):359-363
Fifteen male physical education students were studied. The subjects trained for 4–6 weeks, 2–3 days per week, on a mechanically braked bicycle ergometer. A training session consisted of repeated 30-s ‘all-out’ sprints on a Wingate bicycle ergometer, on which the brake band of the flywheel was loaded with 75 g kg-1 body wt, with rest periods of 15–20 min between consecutive sprints. Thigh muscle biopsies were taken before and after the training period and were analysed for fibre types using a myofibrillar ATPase stain. The proportion of type I fibres decreased from 57 to 48% (P < 0.05) and type IIA fibres increased from 32 to 38% (P < 0.05). This study indicates that it is possible to achieve a fibre type transformation with high-intensity training. The effect of two-legged ‘sprint’ training on muscle fibre type composition may be related to a changed pattern of muscle fibre activation (e.g. an increased stimulation frequency). A change in fibre activation frequency may induce an increased synthesis of type II fibre myosin (fast myosin). Hormonal influences such as enhanced adrenergic stimulation of the muscle fibres cannot be excluded as a contributing factor, however. 相似文献
53.
将HRP微电泳人黑尾蜡嘴雀(Eophona mihratoria)端脑原纹状体粗核内,观察其传入性纤维联系.在下列部位发现有密集的逆行标记细胞:(1):原纹状体带核;(2)上纹状体腹侧尾核;(3)新纹状体前部大细胞核外侧部;(4)脑桥蓝斑.以上标记细胞均出现在同侧.结果表明,原纹状体粗核接受原纹状体带核、上纹状体腹侧尾核、新纹状体前部大细胞核外侧部及脑桥蓝斑的传入性投射. 相似文献
54.
Effects of endurance training on myosin heavy-chain isoforms and enzyme activity in the rat diaphragm 总被引:2,自引:0,他引:2
Takao Sugiura Akio Morimoto Naotoshi Murakami 《Pflügers Archiv : European journal of physiology》1992,421(1):77-81
We investigated the effects of endurance training (20 m/min, 60 min/day, 5 days/week) on myosin heavy-chain (MHC) isoforms and succinic dehydrogenase (SDH) activity in rat crural and costal diaphragms, and plantaris muscles. Although the 4-week endurance training produced significant (P<0.05) increases, both in SDH activity and the percentage of isoform HCIIa in the plantaris of the trained rat compared with the sedentary control rat, these alterations did not occur in either the crural or costal diaphragms. After 10 weeks of endurance training, trained animals had significantly (P<0.05) higher SDH activity in the costal diaphragm and the plantaris. Moreover, a significant (P<0.05) decrease occurred in the percentage of HCIIb in the costal diaphragm, and a significant (P<0.01) decrease in the percentage of HCIIb concomitant with a significant (P<0.05) increase of HCIIa resulted in the plantaris. However, the crural diaphragm did not show any significant changes after 10 weeks of endurance training. These results indicate that endurance training induces an alteration in the expression of an MHC phenotype, in addition to causing an increase in oxidative enzyme activity. However, the alterations in response to endurance training are apparently not uniform, varying between regions and/or kinds of muscles. 相似文献
55.
Peter Ulrich Hans-Jürgen Meyer Bernhard Diehl Günther Meinig 《Neurosurgical review》1987,10(4):305-307
In 12 healthy volunteers with at least an experience of six months in autogenic training (AT), the cerebral blood flow (CBF) was measured at rest, in AT and in hypnosis (H). The results were correlated with individual test profiles. The cortical flow pattern at rest of our AT trained volunteers did not show the hyperfrontality which is described in the literature. This may be interpreted as an effect of better and habitualized relaxation in long trained AT practitioners. This flow pattern corresponds to the low grades of neuroticism and aggressivity found in the tests. Furthermore an activation in central cortical areas and a deactivation in regions which are associated with acoustic and autonomous functions occur.Possible explanations for these phenomena as well as for the relatively low perfusion of the left hemisphere at rest and activation in AT are discussed. The global rise of CBF in H may be an activation effect caused by resistance against the hypnotizer: the deeper the trance, the smaller the CBF increase in the motor cortical area needed for maintaining catalepsy of the right arm and in temporal cortical fields processing acoustic inputs. 相似文献
56.
The purpose of the present study was to improve the quality and the effectiveness of subgingival scaling managed by dental students. A training program was developed and the scaling was performed in jaw models. The teeth of these models were modified in order to ensure a quick inspection of the scaled root surfaces. Artificial "calculus", consisting of a mixture of shellac, umbra, pumice and plaster dissolved in ethanol, was painted on the root surfaces. Following the completion of the scaling test, remaining "calculus" was evaluated by adoption of a grading system. This system had scores from 0 to 3 and was defined by illustrated and described criteria. A menu-directed computer program was developed in order to ensure a rapid transformation of surface scores into clinically-related variables. The output from this program gave valuable information about the proficiency of individual students, as well as about the whole class of students as one body. Other advantages and potentials of this system are described. 相似文献
57.
目的 探讨渐进性肌肉放松训练配合心理干预对艾滋病患者服药依从性及心理状态的影响。方法 选择2017年8月—2020年8月于本院就诊的68例艾滋病患者,按随机数字表法分为对照组和观察组,每组34例。对照组实施常规护理干预,观察组在此基础上实施渐进性肌肉放松训练配合心理干预,比较两组服药依从性及医院焦虑抑郁量表(HospitalAnxietyand Depresseo Scale,HAD)评分。结果 观察组服药总依从率为97.06%,高于对照组的70.59%,(χ2=8.785,P=0.003);观察组干预2周后焦虑评分为(14.35±1.67)分、抑郁评分为(13.98±1.38)分,均低于对照组的(15.63±1.59)分、(15.08±1.27)分,(t=3.237、3.420,P=0.002、0.001)。结论 渐进性肌肉放松训练配合心理干预应用于艾滋病患者,能够提高患者服药依从性,改善患者心理状态。 相似文献
58.
Suboptimal nutrition is a major cause of morbidity and mortality in the United Kingdom (UK). Although patients cite physicians as trusted information sources on diet and weight loss, studies suggest that the management of nutrition-related disorders is hindered by insufficient medical education and training. Objectives of this study were to: (1) Quantify nutrition-related learning objectives (NLOs) in UK postgraduate medical training curriculums and assess variation across specialties; (2) assess inclusion of nutrition-related modules; (3) assess the extent to which NLOs are knowledge-, skill-, or behaviour-based, and in which Good Medical Practice (GMP) Domain(s) they fall. 43 current postgraduate curriculums, approved by the General Medical Council (GMC) and representing a spectrum of patient-facing training pathways in the UK, were included. NLOs were identified using four keywords: ‘nutrition’, ‘diet’, ‘obesity’, and ‘lifestyle’. Where a keyword was used in a titled section followed by a number of objectives, this was designated as a ‘module’. Where possible, NLOs were coded with the information to address objective 3. A median of 15 NLOs (mean 24) were identified per curriculum. Eleven specialties (25.6%) had five or less NLOs identified, including General Practice. Surgical curriculums had a higher number of NLOs compared with medical (median 30 and 8.5, respectively), as well as a higher inclusion rate of nutrition-related modules (100% of curriculums versus 34.4%, respectively). 52.9% of NLOs were knowledge-based, 34.9% skill-based, and 12.2% behaviour-based. The most common GMP Domain assigned to NLOs was Domain 1: Knowledge, Skills and Performance (53.0%), followed by Domain 2: Safety and Quality (20.6%), 3: Communication, Partnership and Teamwork (18.7%), and 4: Maintaining Trust (7.7%). This study demonstrates considerable variability in the number of nutrition-related learning objectives in UK postgraduate medical training. As insufficient nutrition education and training may underlie inadequate doctor-patient discussions, the results of this analysis suggest a need for further evaluation of nutrition-related competencies in postgraduate training. 相似文献
59.
Mansour Ghasemikaram Klaus Engelke Matthias Kohl Simon von Stengel Wolfgang Kemmler 《Nutrients》2021,13(5)
The present study aimed to determine the effect of detraining on muscle quality (MQ) in older men with osteosarcopenia. Forty-three community-dwelling older men (78 ± 4 years) were randomly allocated to a consistently supervised high-intensity resistance exercise training (HIRT) group (n = 21) or a control group (CG, n = 22). The HIRT scheduled a periodized single set protocol twice weekly. After the intervention, the men were subjected to six months of detraining. Muscle quality (MQ), defined as maximum isokinetic hip/leg extensor strength per unit of mid-thigh intra-fascia volume, was determined by magnetic resonance imaging (MRI) or per unit of thigh muscle mass assessed by dual-energy X-ray absorptiometry (DXA). Intention-to-treat analysis with multiple imputations was applied. We observed significant exercise effects for MQ (p = 0.001). During detraining, the HIRT group lost about one-third of the intervention-induced gain and displayed significantly (p = 0.001) higher MQ reductions compared to the CG. Nevertheless, after training and detraining, the overall intervention effect on MQ remained significant (p ≤ 0.004). In summary, six months of absence from HIRT induce a significant deleterious effect on MQ in older osteosarcopenic men. We conclude that intermitted training programs with training breaks of six months and longer should be replaced by largely continuous exercise programs, at least when addressing MQ parameters. 相似文献
60.
Aaron Persinger Matthew Butawan Martina Faietti Ashley Pryke Kyley Rose Marie van der Merwe Richard J. Bloomer Melissa J. Puppa 《Nutrients》2021,13(5)
Time-restricted feeding (TRF) is becoming a popular way of eating in physically active populations, despite a lack of research on metabolic and performance outcomes as they relate to the timing of food consumption in relation to the time of exercise. The purpose of this study was to determine if the timing of feeding/fasting after exercise training differently affects muscle metabolic flexibility and response to an acute bout of exercise. Male C57BL/6 mice were randomized to one of three groups for 8 weeks. The control had ad libitum access to food before and after exercise training. TRF-immediate had immediate access to food for 6 h following exercise training and the TRF-delayed group had access to food 5-h post exercise for 6 h. The timing of fasting did not impact performance in a run to fatigue despite TRF groups having lower hindlimb muscle mass. TRF-delayed had lower levels of muscle HSL mRNA expression and lower levels of PGC-1α expression but displayed no changes in electron transport chain enzymes. These results suggest that in young populations consuming a healthy diet and exercising, the timing of fasting may not substantially impact metabolic flexibility and running performance. 相似文献