Abstract：
PURPOSE:The purpose of this study is to compare the time-frequency characteristic, using nonlinearly scaled wavelets, of the EMG signal as well as the three-dimensional (3D) knee kinematics of female and male elite soccer players performing an unanticipated cutting maneuver. METHODS:Fifteen female and 15 male elite soccer players performed several cutting maneuvers during which EMG of eight muscles of the leg and 3D kinematics of the knee were recorded. To create an unanticipated condition, the participants executed one of three tasks, which were signaled to them with an illuminated target board. RESULTS:Male participants generally executed the unanticipated cutting maneuver with a quadriceps activation of higher frequency components. These gender differences were also found at initial ground contact (IC) for the vastii and biceps femoris (BF) muscles. These higher frequencies dominated the signal earlier in time for the BF and later for the tibialis anterior (TA) in women. Furthermore, women performed the cutting task with greater knee abduction than did the men. CONCLUSION:Female athletes adopted a different motor unit recruitment strategy that was particularly evident at, and near, IC resulting in lower frequency components in the EMG signal of the lateral hamstring. This strategy may play a role in explaining the gender bias in anterior cruciate ligament (ACL) injury rates. Gender differences in knee kinematics were also observed, exposing the female ACL to higher strain, which may be the result of differences in neuromuscular strategies to stabilize the knee joint.
journal_name
Med Sci Sports Exercjournal_title
Medicine and science in sports and exerciseauthors
Beaulieu ML,Lamontagne M,Xu Ldoi
10.1249/MSS.0b013e31817b8e9esubject
Has Abstractpub_date
2008-10-01 00:00:00pages
1795-804issue
10eissn
0195-9131issn
1530-0315pii
00005768-200810000-00012journal_volume
40pub_type
杂志文章abstract：INTRODUCTION/PURPOSE:Hyperpnea and hyperinflation have been proposed as contributors to exaggerated energy demands in chronic obstructive pulmonary disease (COPD), yet there are incomplete data on exercise requirements. This study compared total-body energy demands of the internal (unloaded) and external work of cyclin...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/mss.0b013e3180383d50
更新日期：2007-06-01 00:00:00
abstract：PURPOSE:To assess reliability and validity of the 7-d physical activity recall (PAR) in 60- to 80-yr-old men from urban and rural homes in the southeastern United States. METHODS:Two hundred twenty 60- to 80-yr-old men (29% minority ethnicity) from Veterans Affairs primary care clinics completed two PAR interviews at ...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/01.mss.0000139893.65189.f2
更新日期：2004-09-01 00:00:00
abstract：:This 1 year study examined the effect of high impact and low impact activities on bone mineral density (BMD) at the lumbar vertebrae (L2-L4) in healthy, sedentary, early postmenopausal women. Fifteen subjects whose postmenopausal status was verified by the blood levels of follicle stimulating hormone (FSH) and estradi...
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：1992-11-01 00:00:00
abstract：PURPOSE:The objective of this study is to determine whether childhood muscular fitness phenotypes (strength, endurance, and power) are independently associated with adult metabolic syndrome (MetS). METHODS:We conducted a longitudinal study including 737 participants who had muscular fitness measures in 1985 when age 9...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0000000000000955
更新日期：2016-09-01 00:00:00
abstract：PURPOSE:To provide evidence that lower-extremity muscle activity during running is tuned in response to the loading rate of the impact forces at heel-strike. METHODS:Six runners ran two 30-min trials per week for 4 wk. The trials tested two shoes which differed only in the material hardness of the midsole. The shoes w...
journal_title：Medicine and science in sports and exercise
pub_type： 临床试验,杂志文章
doi：10.1097/00005768-200209000-00021
更新日期：2002-09-01 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:Obesity is epidemic in Western societies, with rapid rates of increase in the young. Various methods exist for the assessment of body composition, but these have not been compared in obese children and adolescents. This study compared methods of body composition assessment in obese young people to determine whe...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/01.mss.0000191160.07893.2d
更新日期：2006-03-01 00:00:00
abstract：PURPOSE:Above a given exercise intensity, rapid muscle fatigue will occur. We explored the possibility of assessing torque threshold for peripheral fatigue during single-legged repetitive isometric knee extensor exercise. We hypothesized this fatigue threshold to be related to the general aerobic fitness level and the ...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0b013e318249d701
更新日期：2012-07-01 00:00:00
abstract：PURPOSE:The objective of this study is to determine the effect of body mass index (BMI) on level of agreement between six previously established prediction equations for three commonly used accelerometers to predict summary measures of energy expenditure (EE) in youth. METHODS:One hundred and thirty-one youth between ...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0b013e318267b8f1
更新日期：2012-12-01 00:00:00
abstract：:The purpose of this study was to investigate the association between elite endurance athlete (EEA) status and two restriction fragment length polymorphisms (RFLPs) at the muscle-specific creatine kinase (CKMM) gene locus. Genomic DNA was extracted from white blood cells or lymphoblastoid cell lines of 124 unrelated Ca...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1097/00005768-199711000-00009
更新日期：1997-11-01 00:00:00
abstract：PURPOSE:To better understand the mechanical behavior of healing skeletal muscle; specifically the tissue's response after acute eccentric stretch injury. METHODS:Rabbit tibialis anterior (TA) muscle tendon units were subjected to an in vivo single stretch (eccentric) injury and mechanically evaluated (constant rate el...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/01.MSS.0000084423.39529.C5
更新日期：2003-09-01 00:00:00
abstract：:The cell-to-cell lactate shuttle was introduced in 1984 and has been repeatedly supported by studies using a variety of experimental approaches. Because of its large mass and metabolic capacity, skeletal muscle is probably the major component of the lactate shuttle in terms of both production and consumption. Muscles ...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章,评审
doi：10.1249/MSS.0b013e31815fa580
更新日期：2008-03-01 00:00:00
abstract：PURPOSE:The purpose of this study was twofold: (a) to measure the effects of temporal parameters on both ball velocity and upper limb joint kinetics to identify pathomechanical factors during the tennis serve and (b) to validate these pathomechanical factors by comparing injured and noninjured players. METHODS:The ser...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0b013e318299ae3b
更新日期：2013-11-01 00:00:00
abstract：INTRODUCTION:The vascular endothelium plays an important role in the maintenance of vascular health and the modulation of vascular tone and blood pressure. Recently, it has been demonstrated that blood pressure reactivity to physical activity is greater in the morning, and possibly, diurnal variation in vascular functi...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0b013e318195109c
更新日期：2009-06-01 00:00:00
abstract：:Cellular oxidants include a variety of reactive oxygen, nitrogen, and chlorinating species. It is well established that the increase in metabolic rate in skeletal muscle during contractile activity results in an increased production of oxidants. Failure to remove these oxidants during exercise can result in significan...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章,评审
doi：10.1097/00005768-199907000-00011
更新日期：1999-07-01 00:00:00
abstract：PURPOSE:FRESH START is a randomized controlled trial that will test whether a personally tailored, distance-medicine-based program will increase exercise and fruit and vegetable consumption, and decrease fat intake of individuals recently diagnosed with breast or prostate cancer. METHODS:Early-stage breast and prostat...
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：10.1249/01.MSS.0000053704.28156.0F
更新日期：2003-03-01 00:00:00
abstract：:This study assessed body density (BD) in an ethnically diverse sample of women (African American, Caucasian, Mexican American and Native American) (N = 139) who were between 20 and 30 or 40 and 50 yr of age and of normal weight for their height. BD was assessed using three methods: hydrostatically determined density (...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1097/00005768-199701000-00013
更新日期：1997-01-01 00:00:00
abstract：:We develop an observation system that quantifies the duration, intensity, and frequency of children's physical activities. We use this system to assess the level and tempo of energy expenditure under free-ranging, natural conditions experienced by 15 children aged 6-10 yr in southern California. Observations were reco...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/00005768-199507000-00012
更新日期：1995-07-01 00:00:00
abstract：:Two swims (1993 and 1994) are described which led to post-swim orthostatic intolerance and one episode of syncope in a 50/51-yr-old well-trained and experienced marathon swimmer. The swims of 33 km and 38 km took 12 h 30 s and 17 h 35 min, respectively. Water temperature in each swim was above 23 degrees C and rectal ...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：
更新日期：1995-09-01 00:00:00
abstract：PURPOSE:The present study investigated the effects of severe-intensity interval training at a frequency of once a week on cardiorespiratory function at rest and during exercise. METHODS:Fourteen young healthy males were randomly assigned to either an interval training group or control group. Cardiorespiratory function...
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.0000000000000477
更新日期：2015-04-01 00:00:00
abstract：PURPOSE:The frequency of interruptions in sedentary time (sedentary breaks) is an aspect of sedentary behaviors that may be associated with metabolic health outcomes. The aim of this study was to describe the change in the frequency of sedentary breaks during a 10-yr period from ages 5 to 15 yr. METHODS:The longitudin...
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：:Magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) are new and powerful tools to study tissue biochemistry, and to provide precise anatomical visualization of soft tissue structures. This review focuses on the use of these techniques to study exercise-induced muscle injury. MRS measurements sho...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章,评审
doi：
更新日期：1992-05-01 00:00:00
abstract：UNLABELLED:Skeletal muscle injury is major concern in sport- and occupation-related fields. PURPOSE:We investigated the effects of increasing stretch-shortening contraction (SSC) repetition number in vivo and the resulting changes in functional performance and quantitative morphometry in rat skeletal muscle. METHODS:...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/mss.0b013e3180686dc7
更新日期：2007-08-01 00:00:00
abstract：:Ten subjects were studied to determine within-subject variance (Swi2), and its components, biovariability (Si2) and technological error (Se2) of residual lung volume (RLV). Each subject's RLV was determined 18 times using the oxygen dilution method (O2D) over a 5-day period. Se2 was measured using a 9.0 l spirometer a...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：
更新日期：1986-08-01 00:00:00
abstract：PURPOSE:Oral L-arginine supplementation has been shown to improve treadmill time to exhaustion and resting insulin sensitivity in individuals with peripheral vascular disease and type 2 diabetes, respectively. Furthermore, L-citrulline supplementation increases plasma L-arginine concentration to a level higher than tha...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/01.mss.0000210197.02576.da
更新日期：2006-04-01 00:00:00
abstract：:The purpose of this study was to determine whether competitive and recreational runners would replicate land training intensity during water immersion (WI) running with (V) and without (NV) a flotation vest and during treadmill running (Tm). Seven female competitive runners (CR) and seven female noncompetitive runners...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1097/00005768-199710000-00015
更新日期：1997-10-01 00:00:00
abstract：:Muscle force can be transmitted via connective tissues to neighboring muscles. The goal of this research is to determine the extent to which this effects force summation between synergists during physiological conditions. This manuscript reviews two studies examining the interaction between synergists in cat hindlimb....
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章,评审
doi：10.1249/MSS.0b013e318183c0c3
更新日期：2009-01-01 00:00:00
abstract：PURPOSE:Investigate hemodynamic responses of resistance exercise (RE) with moderate load (i.e., international guidelines for RE of patients) versus RE with high load in patients with coronary artery disease (CAD). METHODS:Medically stable male (n = 11) and female patients (n = 4) treated with PCI or percutaneous coron...
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.0000000000000811
更新日期：2016-04-01 00:00:00
abstract：PURPOSE:This study was designed to compare the differences in EMG and kinematics between successful and unsuccessful attempts in bench pressing at one repetition maximum (1RM) in recreational weight-trained subjects. We hypothesized that failure occurs during the sticking period (the period during which there is a temp...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0b013e3181a8c360
更新日期：2009-11-01 00:00:00
abstract：:The purposes of this investigation were to compare selected gait parameters characteristic of running without respiratory apparatus on a treadmill (NOR) with those displayed while wearing a mouthpiece-breathing valve apparatus (MP) and while wearing a respiratory face mask (MASK), and to compare the running economy (R...
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：1993-02-01 00:00:00
