Abstract:
:The purpose of the study was to examine the effects of surgical and nonsurgical treatment of previously immobilized ankle fractures on voluntary and evoked contractile properties before and following fatigue. Twelve control and 12 previously immobilized (4-14 wk postfracture) internally fixated and nonfixated ankles were investigated before and following an isometric, intermittent, submaximal, fatigue protocol of the plantar flexors. Before fatigue, fracture groups had significantly lower force output (42.7 vs 78.8 Nm) and muscle activation (78.3 vs 98.7%) than controls. Decreased activation may be attributed to the inhibitory effects of injured muscle and swelling. All groups had similar force and muscle activation decreases (7-10%) following fatigue; however, the internally fixated group performed significantly fewer contractions during the fatigue test (19) than the nonfixated (71) and controls (61). In contrast to the other groups, internally fixated subjects experienced increased (13%) rather than decreased EMG activity (controls: 10.9%, nonfixated: 21.1%). M-waves and twitch torques potentiated to a similar extent in the fracture groups (4.5 and 5.7%) but decreased significantly in the control group (24.2 and 9.8%). The similar fatigue durations of non-fixated subjects compared with controls may be attributed to a lack of impairment in nonfixated neuromuscular propagation and contractile kinetics, while the increased fatigability of fixated subjects with a similar lack of evoked contractile property impairments suggested a greater intrinsic fatigability.
journal_name
Med Sci Sports Exercjournal_title
Medicine and science in sports and exerciseauthors
Behm DG,St-Pierre DMdoi
10.1097/00005768-199709000-00001subject
Has Abstractpub_date
1997-09-01 00:00:00pages
1115-23issue
9eissn
0195-9131issn
1530-0315journal_volume
29pub_type
杂志文章abstract:PURPOSE:The purpose of this investigation was to evaluate the accuracy of a new air displacement plethysmograph, BOD POD Body Composition System, for determining %fat in collegiate football players. METHODS:Body fatness was estimated from body density (Db), which was measured on the same day using the BOD POD and hydr...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199909000-00019
更新日期:1999-09-01 00:00:00
abstract:PURPOSE:Concurrent and construct validity of the OMNI-Walk/Run Scale of Perceived Exertion was examined using young adult women and men (18-36 yr). METHODS:Concurrent validity was established by correlating OMNI-Walk/Run Scale ratings of perceived exertion (RPE-OMNI) with oxygen uptake (VO2), relative maximal oxygen u...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000142310.97274.94
更新日期:2004-10-01 00:00:00
abstract::We investigated the breath-by-breath pattern of ventilatory response to bicycle exercise in seven elite male cyclists (VO2max = 71.7 ml X min-1 X kg-1) and ten sedentary males (VO2max = 47.3 ml X min-1 X kg-1) to analyze differences in breathing patterns between individuals with normal and high exercise ventilations (...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1983-01-01 00:00:00
abstract::In 1983 a representative sample of Danish adolescents 16-19 yr of age were selected to participate in a study to determine risk profile for coronary heart disease. Eight years later (1991), we performed a follow-up study of the same participants 23-27 yr of age to compare risk factors. In the young adults power was ge...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1994-08-01 00:00:00
abstract:PURPOSE:This study compared the ActiGraph accelerometer model 7164 (AM1) with the ActiGraph GT1M (AM2) during self-paced locomotion. METHODS:Participants (n = 116, aged 18-73 yr, mean body mass index = 26.1 kg x m(-2)) walked at self-selected slow, medium, and fast speeds around an indoor circular hallway (0.47 km). B...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3181c29e90
更新日期:2010-05-01 00:00:00
abstract:PURPOSE:Dual-energy x-ray absorptiometry (DXA) is becoming a popular tool to measure body composition in athletes, owing to its ease of operation and comprehensive analysis of body composition. This study represents the first systematic investigation of the reliability of DXA measurements of body composition in trained...
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.0b013e318228b60e
更新日期:2012-01-01 00:00:00
abstract:INTRODUCTION:It is well established that hemodynamic dysfunction, resulting in diminished upper-extremity work capacity, occurs in persons with spinal cord injury (SCI) as compared with those who are nondisabled (ND). Although it has been shown that persons with paraplegia display higher values of heart rate (HR) with ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200209000-00001
更新日期:2002-09-01 00:00:00
abstract:PURPOSE:Exercise training restores innate immune system cell function in post-myocardial infarction (post-MI) rats. However, studies of the involvement of lymphocyte (Ly) in the setting of the congestive heart failure (CHF) are few. To address this issue, we investigated the function of Ly obtained from cervical lymph ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e31815ed6d2
更新日期:2008-03-01 00:00:00
abstract::Nine men participated in an exercise program (five days a week for 10 weeks) that was designed to strengthen the quadriceps muscles. This study was undertaken to determine if heavy resistance training results in an increase in endurance, Vo2max and whether the differences that are normally observed during bicycle and ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1980-01-01 00:00:00
abstract::Conflicting data on the alterations in the maximal exercise response to beta blockade (BB) may be the result of differences in the length of time the subject has been on medication, i.e., hours vs days. The purpose of this study was to examine maximal exercise responses during acute and chronic administration of BB. T...
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:
更新日期:1988-12-01 00:00:00
abstract:INTRODUCTION:Current athlete-specific protein recommendations are based almost exclusively on research in males. PURPOSE:Using the minimally invasive indicator amino acid oxidation technique, we determined the daily protein intake that maximizes whole-body protein synthesis (PS) and net protein balance (NB) after exer...
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.0000000000001832
更新日期:2019-04-01 00:00:00
abstract::It is commonly believed that exposure to cold environmental temperatures depresses immune function and increases the risk for infection. This review paper will 1) present an overview of human physiological responses to cold exposure, 2) present the human studies examining the effects of cold exposure on immune respons...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1097/00005768-200212000-00023
更新日期:2002-12-01 00:00:00
abstract:PURPOSE:The aim was to determine the feasibility of a 6-wk speed-based exercise program that could be used to initiate new exercise behaviors and to improve rapid movement in older adults approaching frailty. METHODS:The intervention group included 14 older adults (3 males and 11 females; mean ± SD, age = 70 ± 7.6 yr,...
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.0000000000001069
更新日期:2017-01-01 00:00:00
abstract::We investigated the relationship of aerobic fitness to the response of volume-regulating hormones to acute simulated microgravity. Six untrained (UT) and six endurance-trained (ET) healthy young males were studied in the head-down tilt (HDT) position of -6 degrees for 4 h. Peak oxygen uptake (VO2peak) and plasma volum...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1992-09-01 00:00:00
abstract::This article focuses on sports related spinal cord and nerve injuries, ranging from mild "stinger" syndrome to complete quadriplegia. Particular emphasis is placed on recommendations for return to competition after such injuries. Cervical spinal cord symptoms after a spine injury from contact sports require a more pre...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199707001-00005
更新日期:1997-07-01 00:00:00
abstract::Since the first reported use of knee braces for prophylactic purposes in 1979, these braces have gone through a period of widespread popularity and use, followed by increasing skepticism as to their effectiveness. Early use was unsupported by significant clinical or laboratory data. Multiple studies regarding prophyla...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:
更新日期:1991-07-01 00:00:00
abstract::Laboratory studies using direct calorimetry, a technique which is no longer either rare or difficult, have shown no essential differences between men and women who gain weight easily and the always lean. Both groups gained weight similarly when overeating by 1,000 kcal X d-1. Thermogenic responses to eating and the en...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1986-02-01 00:00:00
abstract:PURPOSE:The purpose of this study was to examine the impact of exercise-induced metabolic stress on hormonal responses and chronic muscular adaptations. METHODS:We compared the acute and long-term effects of an "NR regimen" (no-rest regimen) and those of a "WR regimen" (regimen with rest period within a set). Twenty-s...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:2005-06-01 00:00:00
abstract::Canine skeletal muscle preparations in situ contain varying mixtures of fast and slow fatigue resistant fibers. All vessels on the arterial side of the vascular bed in these preparations from the conduit arteries to the arterioles contribute to the vascular resistance. The vascular beds autoregulate at rest and during...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1249/00005768-198810001-00004
更新日期:1988-10-01 00:00:00
abstract:PURPOSE:Muscle sympathetic nerve activity (MSNA) is increased in older endurance-trained men, yet the reflex sympathetic forearm vasoconstrictor response to graded lower body negative pressure (LBNP) diminishes with age. The aim of this study was to assess the influence of aerobic exercise capacity on this altered neur...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e31822a68a5
更新日期:2012-02-01 00:00:00
abstract:INTRODUCTION/PURPOSE:Critical power (CP) is a fundamental parameter defining high-intensity exercise tolerance; however, its physiological determinants are incompletely understood. The present study determined the impact of hyperoxia on CP, the time constant of phase II pulmonary oxygen uptake kinetics (τV˙O2), and mus...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000002234
更新日期:2020-05-01 00:00:00
abstract::Existing cross-sectional studies on plasma catecholamine activity provide no support for the concept that a markedly high level of aerobic fitness modifies sympathoadrenal response to an acute psychological challenge in humans. In contrast, compromised sympathetic nervous system activity has been observed in individua...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:
更新日期:1991-07-01 00:00:00
abstract:BACKGROUND:The Sedentary Sphere is a method for the analysis, identification, and visual presentation of sedentary behaviors from a wrist-worn triaxial accelerometer. PURPOSE:This study aimed to introduce the concept of the Sedentary Sphere and to determine the accuracy of posture classification from wrist acceleromet...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000000224
更新日期:2014-06-01 00:00:00
abstract:PURPOSE:To determine whether lactate profiling could detect changes in discrete aspects of endurance fitness in world-ranked swimmers during a season. METHODS:Eight male and four female Australian National Team swimmers aged 20--27 yr undertook a 7 x 200-m incremental swimming step test on four occasions over an 8-mon...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200102000-00019
更新日期:2001-02-01 00:00:00
abstract::The Age Discrimination in Employment Act has raised the issue of Bona Fide Occupational Qualifications for employment in the public safety sector. Complicating the issue is the number of lawsuits filed for violation of the Age Discrimination in Employment Act. Physical performance testing as an alternative to arbitrar...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1987-04-01 00:00:00
abstract:PURPOSE:Aerobic training (AT) and high-intensity intermittent training (HIIT) reduce arterial stiffness, whereas resistance training (RT) induces deterioration of or no change in arterial stiffness. However, the molecular mechanism of these effects of different exercise modes remains unclear. This study aimed to clarif...
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.0000000000001567
更新日期:2018-06-01 00:00:00
abstract:PURPOSE:This study examines heavy episodic alcohol consumption and associated harms in collegiate athletes in the United States. The factors which may promote or deter such use are explored. METHODS:Randomly selected students in a nationally representative sample of 4-yr colleges in the United States completed self-re...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200101000-00008
更新日期:2001-01-01 00:00:00
abstract::Body composition has become a major field of interest for many exercise and sport scientists as well as clinicians who specialize in the prevention of and rehabilitation from hypokinetic diseases. This paper discusses the state of the art within selected areas of body composition, identifying significant areas of cont...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:
更新日期:1983-01-01 00:00:00
abstract::The effects of weight loss (dehydration) techniques (which mimicked techniques used prior to actual competition) used by intercollegiate wrestlers on selected physiological parameters (strength, anaerobic power, anaerobic capacity, the lactate threshold (LT), and peak aerobic power) were examined in seven intercollegi...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1990-04-01 00:00:00
abstract:PURPOSE:Most studies of physical fitness change have been relatively small, not population-based, and lacking in women and nonwhites. The purpose of this analysis was to evaluate the 7-yr change in physical fitness in a biracial (black and white) population of young men and women. METHODS:We evaluated change in exerci...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199803000-00014
更新日期:1998-03-01 00:00:00