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 weighing, and thigh volume and cross-sectional area were also determined. No difference was observed in the absolute MWO10, MWO30, and MWO90 between girls and boys at 9 and 11 yr of age. However, significant differences appeared between genders from 13 yr of age onward, anaerobic performances of the knee extensor muscles of girls representing about 75% or even less of those of boys. The analysis of variance revealed that maximal work ouput during the three knee extension tests was significantly greater in males as well as in females from 9 to 18 yr, regardless how performance was related to morphological characteristics. Performance in absolute values or expressed per unit of body weight, fat free mass, and thigh cross-sectional area for the MWO10, MWO30, and MWO90 tests were almost always significantly lower in both genders when performances of the 9-yr-old group were compared with those of the 13-yr-old group or older groups. Improvement in maximal work output during the 10-s, 30-s, or 90-s knee extension tests with age occurred mainly between 9 and 15 yr in both genders. The results of the present study show that there are gender differences in predominantly anaerobic performances during growth and reveal that increase in muscle mass does not appear to be the only factor responsible for the age-related increment in the anaerobic working capacity of the knee extensor muscles.
journal_name
Med Sci Sports Exercjournal_title
Medicine and science in sports and exerciseauthors
Saavedra C,Lagassé P,Bouchard C,Simoneau JAsubject
Has Abstractpub_date
1991-09-01 00:00:00pages
1083-9issue
9eissn
0195-9131issn
1530-0315journal_volume
23pub_type
杂志文章abstract:PURPOSE:It is unclear how muscle strength in tibial rotation and knee abduction change following anterior cruciate ligament (ACL) injury and reconstruction. Such strength changes are likely, considering the oblique orientation of the ACL and the constraint provided by the ACL at various tibial rotation and adduction po...
journal_title:Medicine and science in sports and exercise
pub_type: 临床试验,杂志文章
doi:10.1097/00005768-200201000-00002
更新日期:2002-01-01 00:00:00
abstract:UNLABELLED:Considerable evidence suggests regular physical activity can reduce chronic pain symptoms. The dysfunction of endogenous facilitatory and inhibitory systems has been implicated in multiple chronic pain conditions. However, few studies have investigated the relationship between levels of physical activity and...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3182a69cf1
更新日期:2014-03-01 00:00:00
abstract::We studied gastric and intestinal function by gastric intubation/intestinal perfusion in six healthy male volunteers to evaluate optimal use of a 6% glucose-electrolyte (GES) solution. Gastric volume, residual volume, emptying rate, and secretion were measured for an initial 763 +/- 19 ml gastric load of GES and at th...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199704000-00009
更新日期:1997-04-01 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:UNLABELLED:The cumulative effect of the female athlete triad (Triad) risk factors on the likelihood of low bone mineral density (BMD) in exercising women is unclear. PURPOSE:This study aimed to determine the risk of low BMD in exercising women with multiple Triad risk factors. METHODS:We retrospectively examined cros...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3182a03b8b
更新日期:2014-01-01 00:00:00
abstract:PURPOSE:Data from the general population suggest that habitual exercise decreases bronchial responsiveness, but the possible role of exercise in asthmatics is undefined. The leukotriene receptor antagonist montelukast decreases bronchial responsiveness and exercise-induced symptoms in asthmatic children. This randomize...
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.0b013e31815d9670
更新日期:2008-03-01 00:00:00
abstract:PURPOSE:Lateral knee osteoarthritis (OA) is common after anterior cruciate ligament reconstruction (ACLR), yet gait characteristics associated with lateral knee OA after ACLR are not well understood. This cross-sectional study aimed to compare knee, trunk, pelvis, hip, and ankle kinematics and moments between people wi...
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:PURPOSE:beta2 adrenergic agonists are widely used as doping agents. Their side effects on bone, especially microarchitecture, remain unknown. The purpose of this study was to evaluate the effects of chronic clenbuterol and salbutamol treatment on bones of growing rats. METHODS:Twelve-week-old Wistar female rats were d...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000177592.82507.95
更新日期:2005-09-01 00:00:00
abstract::The purpose of this experiment was to determine whether reflexive, or more broadly, automatic hamstrings excitation could be elicited during isometric, maximum effort, step increases in knee extension torque. Eight healthy subjects without lower extremity dysfunction or injury performed maximum effort isometric knee e...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1992-10-01 00:00:00
abstract:INTRODUCTION:Exercise-induced bronchoconstriction (EIB) is thought to result from osmotic and thermal events of air conditioning during exercise at high ventilation rates. The purpose of this study was to evaluate lung function after exercise and eucapnic voluntary hyperventilation (EVH) while breathing both room-tempe...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000158186.32450.ec
更新日期:2005-04-01 00:00:00
abstract:PURPOSE:The purpose of this study was to investigate neuromuscular characteristics and muscle power as determinants of distance running performance. METHODS:Seventeen male endurance athletes performed a 5-km time trial (5K) that included three separate constant-velocity 200-m laps during the course and a maximal 20-m ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199901000-00020
更新日期:1999-01-01 00:00:00
abstract::Perceptual and physiological congruity was examined during recovery from high-intensity dynamic exercise. Nine males (24.8 +/- 0.6 yr; VO2max; 52.3 +/- 1.5 ml.kg-1.min-1) undertook in random order four maximal treadmill protocols. Treadmill speed was held constant (5.3 km.h-1) while grade was incremented by 2, 4, 6, o...
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:1992-03-01 00:00:00
abstract::Ten highly trained endurance athletes were studied to determine the effects of exposure to low ozone (O3) concentrations on simulated competitive endurance performance and associated physiological and subjective symptom responses. Each subject was randomly exposed to filtered air (FA), and to 0.12, 0.18, and 0.24 ppm ...
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:1986-08-01 00:00:00
abstract:PURPOSE:To study the ventilatory effects of closely monitored cycle ergometer conditioning (HR target, 145-150 beats x min(-1); 25 min/session; three sessions per week) during the second and third pregnancy trimesters (TMs) in healthy human pregnancy. METHODS:Subjects were 27 previously sedentary pregnant women (exerc...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199801000-00004
更新日期:1998-01-01 00:00:00
abstract::The 1-mile run/walk test is the field test of choice for evaluating maximal aerobic power (VO2max) in school-aged children. The objective of this study was to determine the relative importance of selected metabolic determinants of mile run/walk performance in children 6-14 yr of age. Mile run/walk time (MRWT), VO2max,...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1991-05-01 00:00:00
abstract:PURPOSE:Heart rate (HR) is widely used to adjust exercise intensity in aerobic training. Training HR recommendations are calculated often from simple equations. Because at lactate steady state (LASS) may be an intensity of exercise eliciting similar objective measures of intensity and similar subjective measures of met...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200205000-00024
更新日期:2002-05-01 00:00:00
abstract:PURPOSE:This study examined some physiological and performance responses to a 6-d taper, and the influence of training intensity and volume on these responses. METHODS:After 15 wk of training, 8 well-trained male middle-distance runners were randomly assigned to either a moderate volume taper (MVT, N = 4) or a low vol...
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:10.1097/00005768-200002000-00038
更新日期:2000-02-01 00:00:00
abstract:BACKGROUND:Sensitization of mechanosensitive afferents, which contribute to the exercise pressor reflex, has been recognized as a characteristic of patients with heart failure (HF); however, the hemodynamic implications of this hypersensitivity are unclear. OBJECTIVES:The present study used passive leg movement (PLM) ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000000782
更新日期:2016-03-01 00:00:00
abstract:PURPOSE:Habitual running has been associated with reduced risk of cataract development in one prospective study. The purposes of the current analyses were to provide further evidence of this potentially important benefit of vigorous exercise and to test whether moderate exercise (e.g., walking) provides as significant ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e31828121d0
更新日期:2013-06-01 00:00:00
abstract:PURPOSE:Unilateral strength training strengthens not only the muscles on the trained side but also the homologous muscles on the untrained side; however, the magnitude of this interlimb cross-education is modest. We tested the hypothesis that heightened sensory feedback by mirror viewing the exercising hand would augme...
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.0000000000000871
更新日期:2016-06-01 00:00:00
abstract::Walking is an important form of physical activity. It is practiced by people of nearly all ages, throughout the world. Walking is an integral part of life, and there is accumulating evidence that it is essential to good health. There are many ways to measure walking including pedometers, accelerometers, trail counters...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1249/MSS.0b013e31817c699c
更新日期:2008-07-01 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:PURPOSE:Ultraendurance exercise is steadily growing in popularity; however, the effect of increasingly prolonged durations of exercise on the vascular endothelium is unknown. The aim of this study was to characterize the effect of various ultramarathon running distances on vascular form and function. METHODS:We evalua...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000002493
更新日期:2020-08-15 00:00:00
abstract::Twelve male swimmers were studied psychologically before, during, and after 10 d of increased training. Daily training distance was increased from 4,000 to 9,000 m.d-1, and intensity was maintained at 94% of VO2max. Three of the swimmers were unable to tolerate the increased training load, and they did the same distan...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/00005768-198808000-00014
更新日期:1988-08-01 00:00:00
abstract:PURPOSE:Aerodynamic drag plays an important role in performance for athletes practicing sports that involve high-velocity motions. In giant slalom, the skier is continuously changing his/her body posture, and this affects the energy dissipated in aerodynamic drag. It is therefore important to quantify this energy to un...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3182443315
更新日期:2012-06-01 00:00:00
abstract:PURPOSE:Few epidemiological studies have been conducted among middle-aged women on long-term total and specific physical activity (PA) trends. We studied in a cross-sectional setting the relationship of self-reported total daily PA with age and calendar time. METHODS:In a population-based cohort of 38,988 women aged 4...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000185086.19220.b3
更新日期:2006-02-01 00:00:00
abstract:PURPOSE:To characterize the hemodynamic and ventilatory responses to exercise in a group of patients with unexplained dyspnea, increased risk for pulmonary arterial hypertension (PAH), and an elevated mean pulmonary artery pressure (mPAP; >30 mm Hg) on exercise. METHODS:A total of 37 symptomatic patients at risk of PA...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e318204cdac
更新日期:2011-06-01 00:00:00
abstract::Six adult females with normal menstrual cycles (28-31 d in length) volunteered to exercise on a bicycle ergometer on five different days of their menstrual cycles (days 2, 8, 14, 20, and 26; day 1 = onset of menstruation). Each day the subjects exercised at a maximum work load (184.4 W) and at four submaximal exercise...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1982-01-01 00:00:00
abstract::The coordination of blood flow control in exercising skeletal muscle is exemplified by the interaction among muscle fibers, nerves, and the smooth muscle and endothelial cells which comprise the resistance vasculature. During functional hyperemia in active muscle, maximal flow exceeds resting values by 10- to 50-fold,...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:
更新日期:1995-08-01 00:00:00
abstract:PURPOSE:A twin design was used to test whether the association between exercise behavior and heart rate and the association between exercise behavior and respiratory sinus arrhythmia (RSA) derive from a common genetic factor. METHODS:Data were available from 157 adolescent (aged 13-22) and 208 middle-aged twin pairs (...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.MSS.0000079073.20399.11
更新日期:2003-08-01 00:00:00