Abstract：
:We have studied the effect of exercise on the percentage of free plasma estradiol 17-beta (E2) and testosterone (T) in 13 untrained (UT) and 8 trained (marathon runners, MR) eumenorrheic women. All women performed a standardized bicycle ergometer (UT) or treadmill (MR) test in the follicular and luteal phases of their menstrual cycles (15-min consecutive work loads of 60%, 70%, and 80% VO2 max to exhaustion). Blood was drawn through an indwelling venous catheter at 15 and 2 min before and immediately after exercise. Free E2 and T was assayed by centrifugal ultrafiltration using undiluted plasma at 37 degrees C (basal samples) and 39 degrees C (exercise samples). Statistical analysis was performed by a two-tailed paired t test. In the UT, the basal percentage of free E2 was measured to be 1.55% +/- 0.24% (mean +/- SD) in the follicular phase and 1.62% +/- 0.32% in the luteal phase (differences NS). In the MR, these values were 1.22% +/- 0.25% and 1.25% +/- 0.12% for the follicular and luteal phases, respectively. The differences between the groups were not significant. Exercise did not provoke significant changes in free E2 in either of the groups. Constrastingly, exercise induced a significant (P less than 0.02) increase in the percentage of free T from 1.56% +/- 0.27% to 2.1% +/- 0.36% and from 1.6% +/- 0.27% to 2.12% +/- 0.33% in the UT in the follicular and luteal phases, respectively. In the MR, the free percentage of T increased from 1.04% +/- 0.39% to 1.6% +/-0.16% (follicular phase) and from 1.24% +/- 0.22% to 1.67% +/- 0.18% (P less than 0.02).
journal_name
Int J Sports Medjournal_title
International journal of sports medicineauthors
Keizer HA,Beckers E,de Haan J,Janssen GM,Kuipers H,van Kranenburg G,Geurten Pdoi
10.1055/s-2008-1025721subject
Has Abstractpub_date
1987-12-01 00:00:00pages
151-3eissn
0172-4622issn
1439-3964journal_volume
8 Suppl 3pub_type
杂志文章abstract：:The peripheral adaptation process associated with repeating eccentric training over a longer period of time was studied in m. vastus lateralis of eleven healthy males aged 24 +/- 4 years. The maximal dynamic concentric muscle strength was only slightly improved after 8 weeks of training. However, eccentric work capaci...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2008-1026031
更新日期：1983-08-01 00:00:00
abstract：:The determination of anaerobic capacity (AC) using treadmill ergometry is problematic from a methodological, as well as a technical standpoint. In this study, a procedure from Monod and Scherrer was modified to examine whether realistic magnitudes of AC could be determined using three subject groups with different lev...
journal_title：International journal of sports medicine
pub_type： 临床试验,杂志文章
doi：10.1055/s-2004-821228
更新日期：2005-09-01 00:00:00
abstract：:The purpose of this study was to examine whether lower body positive pressure (LBPP) could improve maximal performance in paraplegic subjects (P). LBPP may diminish venous blood pooling (VBP) below the lesion and, therefore, support the redistribution of blood during exercise. Twelve male P subjects with complete spin...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-1021192
更新日期：1993-10-01 00:00:00
abstract：:This study was undertaken to evaluate the effects of the supine posture, immersion, and swimming on hormones involved in the regulation of hydrosaline equilibrium. Plasma levels of atrial natriuretic peptide (ANP), arginine vasopressin (AVP), plasma renin activity (PRA), and aldosterone (ALDO) were measured by radioim...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-1024933
更新日期：1989-12-01 00:00:00
abstract：:The aim of the present study was to compare the physiological responses when the crank rate was chosen spontaneously (Ts) or set at +/- 10% (T-10%, T+10%) of the freely chosen rate, during two upper body exercises: i) a sub-maximal test (T(SUB)) in which intensities ranged from 50 to 80% (118.4 +/- 10.2 to 189.5 +/- 1...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-971124
更新日期：1999-05-01 00:00:00
abstract：:The aim of this study was to determine long term changes in shoulder and elbow joints of former elite javelin throwers. Twenty-one elite javelin throwers were examined at an average of 19 years after the end of their high performance phase. Mean age at examination was 50 years. Functional assessment of both shoulders ...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2001-13814
更新日期：2001-05-01 00:00:00
abstract：:Based on the assumption that the stretch-shortening cycle is a natural way of muscle function, the occurrence of such a cycle was investigated in a diagonal technique of cross-country skiing. Cinematographic, special force platform, and telemetered EMG techniques were employed. The four subjects studied were all elite...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2008-1025703
更新日期：1987-03-01 00:00:00
abstract：:Chlorhexidine-containing mouthwash (STRONG), which disturbs oral microflora, has been shown to diminish the rise in plasma nitrite concentration ([NO2-]) and attenuate the reduction in resting blood pressure (BP) typically seen after acute nitrate (NO3-) ingestion. We aimed to determine whether STRONG and weaker antis...
journal_title：International journal of sports medicine
pub_type： 杂志文章,随机对照试验
doi：10.1055/s-0035-1554700
更新日期：2015-12-01 00:00:00
abstract：:The purpose of this study was to investigate the effects of short-term, high-intensity sprint training on the root mean squared (RMS) and median frequency (MF) derived from surface electromyography (EMG), as well as peak power, mean power, total work, and plasma lactate levels in trained cyclists when performed concur...
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-2004-819945
更新日期：2004-02-01 00:00:00
abstract：:It has been suggested in previous studies that the difference in endurance performance between males and females is related to gender-specific differences in cardiac function. Other studies have not equated males and females for physical condition, and this may have contributed to the findings. The purpose of this stu...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-1024696
更新日期：1991-08-01 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 anaerobic threshold (AnT) seems to be not only a physiologic boundary but also a transition after which swimmers technique changes, modifying their biomechanical behaviour. We expanded the AnT concept to a biophysical construct in the four conventional swimming techniques. Seventy-two elite swimmers performed a 5×...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/a-0975-9532
更新日期：2020-05-01 00:00:00
abstract：:During rowing, the respiratory musculature is confronted with dual demands: assisting the propulsive force generation and as the effector for ventilatory control. We determined the pulmomechanical and breathing pattern features of rowing-induced hyperpnea in five national class rowers (18 years old). Each subject perf...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-1021217
更新日期：1993-09-01 00:00:00
abstract：:The O2 equivalent of lactic acid accumulation in blood was estimated from data on ten subjects acclimatized to altitudes up to 6500 m in the course of a Mt. Everest expedition. The calculated value of the O2 equivalent of La by standard least squares regression was 2.07 +/- 0.4 l O2 for a rise of blood lactic acid con...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-1024850
更新日期：1990-02-01 00:00:00
abstract：:This study evaluated the respiratory effects of a single dive in children. Eighteen young divers and 18 controls participated in our study (age range: 9 - 13 years). Volumes and expiratory flow rates were measured 20 minutes before and 10 minutes after one air dive (3 meters, 25 minutes). Before the dive, no differenc...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2006-923810
更新日期：2006-11-01 00:00:00
abstract：:During an overhead throw, the gluteal muscle group stabilizes the lumbopelvic-hip complex (LPHC), leading to efficient energy transfer from the lower to upper extremity. It has been shown that LPHC instability can lead to throwing pathomechanics. The single leg squat has become a common assessment for LPHC stability, ...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/a-0577-3722
更新日期：2018-07-01 00:00:00
abstract：:The aims of this study were: to compare energy expenditure (EE) estimated from the existing GT3X accelerometer equations and EE measured with indirect calorimetry; to define new equations for EE estimation with the GT3X in youth, adults and older people; and to define GT3X vector magnitude (VM) cut points allowing to ...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-0033-1337945
更新日期：2013-11-01 00:00:00
abstract：:Over the past 25 years sport climbing has developed from an elite extreme sport subculture pursued by few into a mainstream recreational sport enjoyed globally by climbers of all ages, climbing abilities, and with pre-existing health conditions. As the demands and grades of climbing difficulty have increased over this...
journal_title：International journal of sports medicine
pub_type： 杂志文章,评审
doi：10.1055/s-0028-1112143
更新日期：2009-06-01 00:00:00
abstract：:Carbon monoxide (CO) rebreathing procedures are used to assess hemoglobin mass (Hbmass) but recent evidence suggests that CO is a signaling molecule that may alter physiological functions. We examined the effects of 10 days of intermittent, low-dose CO inhalation on Hbmass, aerobic performance predictors, and peak-pow...
journal_title：International journal of sports medicine
pub_type： 杂志文章,随机对照试验
doi：10.1055/s-0042-108197
更新日期：2016-10-01 00:00:00
abstract：:This study examined the relationship between ratings of perceived exertion (RPE, CR-10), heart rate (HR), peak blood lactate (La peak), and immersion (IM) parameters in 17 elite synchronized swimmers performing 30 solo and duet routines during competition. All were video recorded (50 Hz) and an observational instrumen...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-0033-1353177
更新日期：2014-05-01 00:00:00
abstract：:Three different procedures to analyse fencing performances were tested. The test subjects were ten world class epée fencers from the Swedish national team. The procedures involved measurements of reaction time and response time to different stimuli. Test 1 measured the lunging performance as a response to a light. Tes...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-1024736
更新日期：1991-12-01 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：:Hypertension is not uncommon in childhood and adolescence; vascular and renal causes predominate. Non-pharmacologic therapy, including exercise, may lower blood pressure (BP). There are several articles relating to the use of exercise as a therapy for high BP. Most of these show a beneficial effect. The "dose" of exer...
journal_title：International journal of sports medicine
pub_type： 杂志文章,评审
doi：10.1055/s-2000-8497
更新日期：2000-11-01 00:00:00
abstract：:Our purpose was to determine if an acute bout of heading soccer balls adversely affected postural control and self-reported symptoms of cerebral concussion. Thirty-one college-aged soccer players were randomly placed into either a kicking group or a heading group. Subjects either kicked or headed 18 soccer balls over ...
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-2004-819941
更新日期：2004-07-01 00:00:00
abstract：:Declines in exercise capacity throughout an individual's life span can affect function and can ultimately limit the ability to perform activities of daily living. Along with these changes in exercise capacity and function, studies have reported age-associated changes in several parameters of immune status including de...
journal_title：International journal of sports medicine
pub_type： 杂志文章,评审
doi：10.1055/s-2007-972697
更新日期：1997-03-01 00:00:00
abstract：:The present study evaluated the accuracy of predicting velocity and oxygen consumption (VO2) at the LT lactate threshold and FBLC fixed blood lactate concentrations from a 3200-m time trial in women. Forty-four women (mean age = 31.1 yrs, mean ht = 164.9 cm, mean wt = 65.0 kg) completed a treadmill protocol for the de...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-1024821
更新日期：1990-10-01 00:00:00
abstract：:The purpose of this study was to determine the effect of a reduced ventilatory frequency (Vf) on blood gases and acid-base changes during three intensities of cycling exercise. VO2max and lactate threshold workload (LaT) of six subjects were assessed on a Monark ergometer. Experimental rides were performed 1) with no ...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-1024657
更新日期：1991-02-01 00:00:00
abstract：:The alterations in thigh muscle properties of chondromalacia patellae patients during isometric and dynamic endurance tests were studied using a variokinetic knee testing system linked to surface EMG. A total of 41 patients (chondromalacia group) with arthroscopically certified chondromalacia of the patella were studi...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-972962
更新日期：1995-01-01 00:00:00
abstract：:The ActiPed (FitLinxx) is a uniaxial accelerometer, which objectively measures physical activity, uploads the data wirelessly to a website, allowing participants and researchers to view activity levels remotely. The aim was to validate ActiPed's step count, distance travelled and activity time against direct observati...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-0032-1323723
更新日期：2013-05-01 00:00:00
abstract：:To study the relationship between the onset of an increase in dyspnea and ventilatory threshold (VT) in children with congenital heart impairment, sixteen young subjects underwent a cardiopulmonary exercise test with dyspnea perception and ventilatory gas exchange assessments. Dyspnea score was measured from a visual ...
journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2006-924396
更新日期：2007-04-01 00:00:00
