Abstract:
:Cardiovascular responses were obtained during cycling with graded levels of lower-body positive pressure (LBPP) applied to the exercising limbs. Seven men performed four incremental work rate (25 W.min-1) exercise (IWREx) tests to their limit of tolerance while exposed to 0, 15, 30, or 45 Torr LBPP. They also performed four, 6-min constant work rate exercise (CWREx) bouts at two work rates with LBPP's of 0 and 45 Torr. Cardiovascular data were obtained at rest and at 40%, 55%, 75%, and 90% of VO2peak, as well as at minute 5 of CWREx. LBPP did not alter VO2, HR, SV, or cardiac output (Qc) responses at rest or during exercise. However, both 30 and 45 Torr LBPP produced increases in MAP at rest and during exercise (P < 0.05). During CWREx, elevations in blood pressure were mediated via increases in TPR (P < 0.05). Only 45 Torr LBPP elicited a significantly greater blood pressure increase during exercise than rest, suggesting muscle blood flow restriction at this level of LBPP was sufficient to activate a muscle metabo-reflex. These findings suggest that the muscle metabo-reflex is not tonically active during dynamic exercise under normal conditions, but may instead require a critical reduction in muscle blood flow before it is activated.
journal_name
Med Sci Sports Exercjournal_title
Medicine and science in sports and exerciseauthors
Williamson JW,Crandall CG,Potts JT,Raven PBdoi
10.1249/00005768-199406000-00008subject
Has Abstractpub_date
1994-06-01 00:00:00pages
701-8issue
6eissn
0195-9131issn
1530-0315journal_volume
26pub_type
杂志文章abstract:PURPOSE:Exercise training reduces pathological remodeling and improves cardiac function in ischemic heart failure; however, causal mechanisms underlying the cardiac benefits of exercise are poorly understood. Because opening of adenosine triphosphate (ATP)-sensitive K ⁺(KATP) channels protects the heart during myocardi...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000000714
更新日期:2015-12-01 00:00:00
abstract:PURPOSE:The present longitudinal study assessed cardiorespiratory capacity and running economy of Olympic athletes over several decades to measure changes in fitness in an elite group during aging. METHODS:Twenty-six male runners training for the 1968 Olympics were recruited. HR, V˙O2max, ventilation, and running econ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000001407
更新日期:2018-01-01 00:00:00
abstract::The extent of the growth changes in maximal work output during 10 s (MWO10), 30 s (MWO30), and 90 s (MWO90) of maximal repetitive knee flexions and extensions assessed on a modified Hydra-Gym machine was investigated in 84 boys and 83 girls, 9-19 yr of age. Body weight, fat mass and fat free mass by underwater weighin...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1991-09-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200211000-00001
更新日期:2002-11-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000126386.12402.f5
更新日期:2004-05-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199812000-00005
更新日期:1998-12-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/mss.0b013e318074ccd9
更新日期:2007-09-01 00:00:00
abstract:PURPOSE:Physical activity (PA) promotion among youth is a public health priority, and there is a need for robust surveillance systems to help support such initiatives. Existing youth PA self-report instruments that are used for surveillance lack information regarding the types and contexts of activity. Further, these i...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000001562
更新日期:2018-06-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3181ebedf4
更新日期:2011-02-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3182a4e89c
更新日期:2014-02-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1097/00005768-200110000-00009
更新日期:2001-10-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000000671
更新日期:2015-11-01 00:00:00
abstract::Thirty-eight athletes with unilateral patellar tendinopathy (17 with a tendinopathy of the main body of the tendon, and 21 with an insertional tendinopathy) underwent ultrasound-guided multiple percutaneous longitudinal tenotomy under local anaesthetic infiltration after failure of conservative management. Thirty-four...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199911000-00003
更新日期:1999-11-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e31826ea8e3
更新日期:2013-02-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200205000-00004
更新日期:2002-05-01 00:00:00
abstract:PURPOSE:Maternal obesity is known to predispose the offspring to impaired glucose metabolism and obesity associated with low-grade inflammation and hypothalamic dysfunction. Because preventive approaches in this context are missing to date, we aimed to identify molecular mechanisms in the offspring that are affected by...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000000835
更新日期:2016-05-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e318245ca20
更新日期:2012-06-01 00:00:00
abstract::The purpose of this study was to determine the validity and evaluate the accuracy of a portable telemetric oxygen uptake analyzer (K2). Two experiments were carried out: a) using a mechanical lung, the accuracy of the K2 to measure oxygen fractions and minute ventilation following 10 and 60 min of warm-up was determin...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1994-01-01 00:00:00
abstract:BACKGROUND:Stress fracture (SF) injuries in new recruits have long been attributed to low bone mineral density (BMD). Low areal BMD assessed using two-dimensional dual-energy x-ray absorptiometry imaging, however, reflects structural density and is affected by smaller measures of bone geometry. Recent studies support a...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3181893cb7
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199702000-00003
更新日期:1997-02-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,随机对照试验
doi:10.1249/MSS.0b013e3182687e5c
更新日期:2012-12-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200011000-00003
更新日期:2000-11-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000132376.50984.27
更新日期:2004-07-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3181b67544
更新日期:2010-03-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/mss.0b013e3180cc20c7
更新日期:2007-09-01 00:00:00
abstract::We used an algebraic model of resting heart rate (HRr), HRr-mn (HRo), to compare resting parasympathetic (n) and sympathetic (m) influence, intrinsic heart rate (HRo), and resting autonomic balance (Abal) in ten endurance-trained (ET) and ten nontrained (NT) men. The values of m, n, and Abal were determined by selecti...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/00005768-198902000-00008
更新日期:1989-02-01 00:00:00
abstract:PURPOSE:The importance of the brain in sports was recently confirmed by the negative effect of mental fatigue (MF) on sport-specific psychomotor skills. Creatine supplementation improves strength but can also improve cognitive functioning. To explore the role of creatine in combating MF, we evaluated whether creatine s...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,随机对照试验
doi:10.1249/MSS.0000000000002122
更新日期:2020-01-01 00:00:00
abstract:PURPOSE:This study aimed to analyze the influence of foot strike pattern on running economy and biomechanical characteristics in subelite runners with a similar performance level. METHODS:Twenty subelite long-distance runners participated and were divided into two groups according to their foot strike pattern: rearfoo...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000000139
更新日期:2014-03-01 00:00:00
abstract:PURPOSE:The fluctuations in force during a steady contraction can be influenced by age, vision, and level of physiological arousal. The aim of this study was to determine the effects of a stressor on the force fluctuations and information transmission exhibited by young, middle-aged, and older adults when a pinch-grip ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000178103.72988.cd
更新日期:2005-12-01 00:00:00
abstract:PURPOSE:Arterial distensibility decreases with age. This decrease may be associated with the initiation and/or progression of hypertension and atherosclerosis and may be attenuated by positive lifestyle habits, including habitual physical activity. We tested the hypothesis that self-reported sport, leisure, and work ph...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200112000-00014
更新日期:2001-12-01 00:00:00