Abstract:
:The present study was designed to investigate the neuronal control and biomechanical effects of stumbling reactions. To induce these perturbations, a specially prepared treadmill was used which allowed rapid and powerful changes of treadmill speed. EMG recordings of leg muscles were related to cinematic movement patterns. Following an accelerating impulse, the standing leg was displaced in a posterior direction compared with normal gait, with a premature touchdown of the contralateral, swinging leg, forward of the body axis. This was associated with simultaneous activation of the gastrocnemius and biceps femoris of the ipsilateral and the tibialis anterior muscles of the contralateral leg. Following deceleration, the standing leg was displaced in an anterior direction and the contralateral swinging leg touched the ground prematurely behind the body axis. This was associated with activation of the ipsilateral tibialis anterior and rectus femoris and contralateral tibialis anterior muscles. In both conditions, the activation of the lower leg muscles on both sides occurred with a latency of 60-70 ms, monosynaptic responses being absent. In both cases, early touchdown was associated with a forward extension of the arm. It is concluded that the EMG responses are mediated by a polysynaptic spinal pathway to keep the body center of gravity constant and to prevent falling.
journal_name
Int J Sports Medjournal_title
International journal of sports medicineauthors
Gollhofer A,Schmidtbleicher D,Quintern J,Dietz Vdoi
10.1055/s-2008-1025785subject
Has Abstractpub_date
1986-12-01 00:00:00pages
325-9issue
6eissn
0172-4622issn
1439-3964journal_volume
7pub_type
杂志文章abstract::The purpose of this study was to determine whether a post-exercise cryotherapy protocol could facilitate recovery of elbow flexor strength and reduce the severity of delayed onset muscle soreness following eccentric exercise. Eight resistance-trained males (23 +/- 3 yr) performed 64 eccentric elbow flexions with each ...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2007-972686
更新日期:1997-11-01 00:00:00
abstract::This randomized, double-blind, placebo-controlled study examined the influence of 6% carbohydrate ingestion on hormonal and lymphocyte proliferative responses (5 total samples over 9 hours) to 2.5 h of high-intensity running by 30 experienced marathon runners. The T-cell response differed between groups, with the plac...
journal_title:International journal of sports medicine
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1055/s-2007-971962
更新日期:1998-11-01 00:00:00
abstract::The aim of this study was: i) to compute an energy balance of a slalom kayak competition by measuring the percentage contributions of the aerobic and anaerobic energy sources to total metabolic power (E(tot)); and ii) to compare these data with those obtained, on the same subjects, over a flat-water course covered at ...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2005-865922
更新日期:2006-07-01 00:00:00
abstract::The ratio between the amount of hemoglobin in the mature erythrocyte population and the reticulocytes (RBCHb:RetHb ratio) has previously been suggested as a marker to screen for EPO-abuse. We speculated that the reinfusion of blood would lead to a marked increase in this ratio, making it a valuable parameter in the sc...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-0028-1105938
更新日期:2009-04-01 00:00:00
abstract::Wasted left ventricular effort (∆Ew) refers to work required of the left ventricle to eject blood that does not result in increased stroke volume and is related to left ventricular hypertrophy. Literature shows that men and women have differing ventricular and vascular responses to and following exercise. Our purpose ...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-0032-1329990
更新日期:2013-09-01 00:00:00
abstract::The frequency of sister chromatid exchanges (SCE) in the peripheral blood lymphocytes of eighteen healthy old women with 88 style Taichiquan exercise was studied. When compared with eighteen old women without exercise, the training group showed a decreased frequency of SCE in cultured peripheral blood lymphocytes at r...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:
更新日期:1990-04-01 00:00:00
abstract::The influence of exercise training on plasma amino acid concentrations at rest and after exercise was examined in a highly trained group of humans and compared with the response of a control group of nontrained healthy humans. After a bout of intense exercise at the same relative work load, the trained group exhibited...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2007-1024908
更新日期:1989-08-01 00:00:00
abstract::To assess changes of sex hormones, cortisol, prolactin (PRL) and beta-endorphins in an exhaustive aerobic performance, blood samples were taken in 11 endurance trained runners (R) along an ultra-marathon race of 110 km (T1 before the start, T2 at km 33, T3 at km 75 and T4 immediately after completing the race). Result...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2007-972629
更新日期:1997-05-01 00:00:00
abstract::This study compared breathing frequency (fB) during a ventilation threshold (VT) test with fB during a simulated 40 km time trial (40TT) to assess whether fB can be used to monitor exercise intensity. Twenty-six male cyclists (mean +/- SD VO2max = 4.42 +/- 0274 l.min-1) performed an incremental VT ergometer test and a...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2007-973001
更新日期:1995-05-01 00:00:00
abstract::It has been suggested that lactate concentrations may provide a guide to an optimal training intensity. However, lactate concentrations established during incremental exercise in the laboratory are not always indicative of what is occurring during constant-load exercise at the same intensity. Ideally, lactate concentr...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2001-17611
更新日期:2001-10-01 00:00:00
abstract::The aim of the present study was to investigate the relationship between maximal fat oxidation rate (MFO) measured during a progressive exercise test on a cycle ergometer and ultra-endurance performance. 61 male ironman athletes (age: 35±1 yrs. [23-47 yrs.], with a BMI of 23.6±0.3 kg/m2 [20.0-30.1 kg/m2], a body fat p...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-0043-117178
更新日期:2017-11-01 00:00:00
abstract::We investigated the effects of vibration (35 Hz, 45 Hz and 55 Hz) as countermeasure locally applied to unloading hind limbs on bone, muscle and Achilles tendon. 40 female Sprague Dawley rats were divided into 5 groups (n=8, each): tail-suspension (TS), TS plus 35 Hz/0.3 g vibration (TSV35), TS plus 45 Hz/0.3 g vibrati...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-0033-1358468
更新日期:2014-06-01 00:00:00
abstract::Within a 3-year period, from 1980 to 1982, 1124 sports injuries of children aged 6-15 years were treated in the Turku University Central Hospital casualty department. Two-thirds (69%) of the injuries were sustained by boys. Sports injuries represented 21% of the diagnoses related to accidents in this age group. Half o...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2007-1024879
更新日期:1989-04-01 00:00:00
abstract::The aim of the present study was to compare the effects of using different intensities and types of aerobic exercise (i. e., cycle ergometer or running) during concurrent training on neuromuscular adaptations. A total of 44 young women were randomly assigned to 1 of 4 groups: concurrent strength and continuous running...
journal_title:International journal of sports medicine
pub_type: 杂志文章,随机对照试验
doi:10.1055/s-0031-1299698
更新日期:2012-08-01 00:00:00
abstract::There is a potential need for the official criterion of testosterone abuse in sport (the urinary concentration ratio of testosterone glucuronide/epitestosterone glucuronide, TG/EG > 6) to be backed-up by some complementary markers, more particularly in cases of physiologically high TG/EG and when there is suspicion of...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2007-972853
更新日期:1996-07-01 00:00:00
abstract::Acute aerobic exercise produces post-exercise hypotension (PEH). Chinese populations have lower prevalence of cardiovascular disease compared to Caucasians. PEH may be associated cardiovascular disease through its influence on hypertension. The purpose of this study was to compare PEH between Caucasian and Chinese sub...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-0034-1390493
更新日期:2015-03-01 00:00:00
abstract::The aim of the study was to examine the associations between maximal and submaximal field tests with match physical activity and biological maturation in youth football players. Sixty-eight youth football players (U14, U15, U16, U17) performed maximal and submaximal field endurance tests. Biological maturity was estim...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/a-0938-5431
更新日期:2019-09-01 00:00:00
abstract::Recreational scuba diving is a sport of increasing popularity. Previous studies indicating subtle brain injury in asymptomatic divers imply a cumulative effect of minor neural insults in association with diving for professional and/or recreational purposes, over the long-term. This is the first study to investigate pu...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-0031-1284341
更新日期:2011-12-01 00:00:00
abstract::Vigorous and prolonged physical exercise and mechanical involvement of the perineal region might influence prostatic function and measurement of both total (PSA) and free prostate specific antigen (fPSA), decreasing the diagnostic efficiency of the laboratory screening for either benign or neoplastic prostate disorder...
journal_title:International journal of sports medicine
pub_type: 临床试验,杂志文章
doi:10.1055/s-2004-830450
更新日期:2005-01-01 00:00:00
abstract::Long-term side effects of high doses of anabolic androgenic steroids self-administration were evaluated in this study. Twenty male bodybuilders, voluntarily starting steroid self-administration, were followed every 6 months over 2 years. Physical examination, haematological, metabolic and endocrine variables, semen an...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2007-965808
更新日期:2008-08-01 00:00:00
abstract::The aim of the present study was to evaluate a heart transplanted patient who ran a 20-km race 9 months after surgery. Thirty-six healthy male subjects were studied during the same run and served as control group. Biochemical variables were determined in blood and urine samples collected before and after the race. Pos...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2008-1025867
更新日期:1985-12-01 00:00:00
abstract::Metabolic syndrome (MetS) is a cluster of cardiometabolic risk factors with high prevalence among adult populations and elevated costs for public health systems worldwide. Despite the lack of consensus regarding the syndrome definition and diagnosis criteria, it is characterized by the coexistence of risk factors such...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/a-1263-0898
更新日期:2020-10-19 00:00:00
abstract::Because previous researchers have reported a reduced lactic acid production that accompanies a delayed or an absent ventilatory threshold (VTh) in water-based exercise, we hypothesized that the metaboreflex, activated by muscle acidosis, might be absent in fin swimming. This motor response, delaying the occurrence of ...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-0030-1251993
更新日期:2010-08-01 00:00:00
abstract::We aimed to describe the changes in footprint characteristics after 2 types of resistance training sessions performed at different intensities. 18 young subjects (8 men and 10 women) volunteered for the study. All of them performed 2 different resistance training sessions, one with light loads (LS) and the other with ...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-0031-1275354
更新日期:2011-08-01 00:00:00
abstract::Highly repetitive submaximal intermittent contractions of the forearm muscles during periods of 30-50 min partially explain why motorcycle races are so demanding for the neuromuscular system. This study investigated the contribution of central and peripheral mechanisms of fatigue on the exerted and contralateral exten...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-0035-1549959
更新日期:2015-11-01 00:00:00
abstract::The aim of this study was to assess the hypothesis that water intake will accelerate cardiac vagal reactivation after a single session of upper-body resistance exercise. 13 healthy men (26.5±5.9 years) with previous experience in resistance training were enrolled. In visits 1 and 2, participants performed the one-repe...
journal_title:International journal of sports medicine
pub_type: 杂志文章,随机对照试验
doi:10.1055/s-0034-1389971
更新日期:2015-03-01 00:00:00
abstract::This study examined the influence of 28 days of dietary carbohydrate (CHO) supplementation on plasma cytokine responses to cycle ergometry. Sixteen highly trained male cyclists and triathletes (age: 30.6+/-5.6 y; VO2max: 64.8+/-4.7 mL x kg(-1) x min(-1); mean+/-SD) participated in the study. One group (n=8) consumed a...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-0029-1243645
更新日期:2010-03-01 00:00:00
abstract::Food restriction has a great impact on skeletal muscle mass by inducing muscle protein breakdown to provide substrates for energy production through gluconeogenesis. Genetic models of hyper-muscularity interfere with the normal balance between protein synthesis and breakdown which eventually results in extreme muscle ...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-0032-1312605
更新日期:2013-03-01 00:00:00
abstract::The aim of this study was to investigate the influence of a 4-week electromyostimulation training program on the strength of the knee extensors and the vertical jump performance of 10 basketball players. Electromyostimulation sessions were carried out 3 times weekly; each session consisted of 48 contractions. Testing ...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2000-3837
更新日期:2000-08-01 00:00:00
abstract::Electromyographic and force production characteristics of leg extensor muscles of elite weight lifters (n = 14) were examined during isometric, concentric, and various stretch-shortening cycle exercises. The data showed that utilization of stored elastic energy of leg extensor muscles was observable in countermovement...
journal_title:International journal of sports medicine
pub_type: 杂志文章
doi:10.1055/s-2008-1025752
更新日期:1986-06-01 00:00:00