Abstract:
:We compared physiological and perceptual responses to non-weight bearing (cycle) and weight bearing (treadmill) exercise in 16 sedentary women throughout a normal term pregnancy. Subjects were recruited late in the first trimester (less than 13 wk gestation) and were studied at 4 wk intervals throughout pregnancy and 4 wk postpartum (PP). Exercise consisted of four 5 min protocols; two were performed on the cycle (C1 = 50 W; C2 = 75 W) and two on the treadmill (T1 = 66 m.min-1, 2.5% grade; T2 = 66 m.min-1, 12% grade). Measured variables included oxygen consumption (VO2), heart rate (HR), minute ventilation (VE), and ratings of perceived exertion (RPE, 10-point Borg scale). Absolute VO2 (ml.min-1) during cycle exercise increased (P less than 0.001) by 25 wk gestation, while relative VO2 (ml.kg-1.min-1) during treadmill walking was unchanged through late pregnancy and PP. This suggests that cycle exercise is not a true non-weight bearing exercise within a given group of women throughout gestation. Subjects' VO2max values were estimated at each test interval and found to increase (P less than 0.001) by 25-28 wk gestation. Heart rate and RPE responses to exercise remained constant throughout gestation and decreased (P less than 0.01) PP. Although they did not participate in a regular exercise program, it appears that our subjects experienced a mild aerobic training effect during late pregnancy.
journal_name
Med Sci Sports Exercjournal_title
Medicine and science in sports and exerciseauthors
Pivarnik JM,Lee W,Miller JFsubject
Has Abstractpub_date
1991-04-01 00:00:00pages
470-5issue
4eissn
0195-9131issn
1530-0315journal_volume
23pub_type
杂志文章abstract:PURPOSE:Studies have shown that absolute intensity of physical activity is associated with reduced risk of preeclampsia. This analysis was performed to examine whether relative intensity may also be related to preeclampsia risk. METHODS:Using data from a case-control study conducted from 1998 to 2002, the authors asse...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000175862.41620.41
更新日期:2005-11-01 00:00:00
abstract::The immune response was assessed in 13 competitive bodybuilders self-administering anabolic-androgenic steroids and ten competitive bodybuilders not administering these drugs. Laboratory assessment included the number and relative distribution of T-cells, T-helper/inducer cells, T-cytotoxic/suppressor cells, activated...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:
更新日期:1989-08-01 00:00:00
abstract:UNLABELLED:High-speed auto racing has been demonstrated to produce accelerated heart rate (HR) during competition. However, it has not been determined whether the increase in HR was due to physical work efforts or a result of emotional stress. PURPOSE:The purpose of this investigation was to examine the physiological ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200212000-00033
更新日期:2002-12-01 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:BACKGROUND:Skeletal muscle from lean and obese subjects elicit differential adaptations in response to exercise/muscle contractions. In order to determine whether obesity alters the adaptations in mitochondrial dynamics in response to exercise/muscle contractions and whether any of these distinct adaptations are linked...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000002580
更新日期:2020-12-11 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:To determine which combination of landing protocol and analysis technique would be the most effective at detecting differences in dynamic stability between healthy subjects and subjects with functional ankle instability (FAI). METHODS:Fifty-eight subjects participated in this investigation: 29 healthy individu...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000149887.84238.6c
更新日期:2005-02-01 00:00:00
abstract::Sex is a potent modifier of the cardiovascular system because males and females differ in several aspects of the heart's biology and physiology. Epidemiologically, premenopausal women possess a distinct advantage over men in the occurrence of cardiovascular heart disease; however, this advantage shifts to men once a n...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1249/MSS.0b013e3181621311
更新日期:2008-04-01 00:00:00
abstract::Throughout a beat swinging motion prior to a kip the gymnast changes the relative orientation of his legs and head-torso with respect to his arms. It was observed that if these changes occurred in a correct order he could rapidly increase his swing with his limited strength. If changes in orientation of the body parts...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1980-04-01 00:00:00
abstract:PURPOSE:The purpose of this study was to determine whether there is a relationship between overall fitness improvement and varying amounts of running and movement mileage. METHODS:Subjects were male U.S. Navy recruits (N = 1703, 25 divisions), ages 17-35 yr (mean age = 20.1 +/- 2.9 yr), who attended boot camp from Apr...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200106000-00024
更新日期:2001-06-01 00:00:00
abstract::The purpose of this investigation was to determine the influence of post-exercise carbohydrate (CHO) intake on the rate of muscle glycogen resynthesis after high intensity weight resistance exercise in subjects not currently weight training. In a cross-over design, eight male subjects performed sets (mean = 8.8) of si...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1993-03-01 00:00:00
abstract:BACKGROUND:Because physical activity researchers are increasingly using objective portable devices, this review describes the current state of the technology to assess physical activity, with a focus on specific sensors and sensor properties currently used in monitors and their strengths and weaknesses. Additional sens...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1249/MSS.0b013e3182399bc8
更新日期:2012-01-01 00:00:00
abstract:PURPOSE:For most people, the benefits of physical activity far outweigh the risks. Research has suggested that exercise preparticipation questionnaires might refer an unwarranted number of adults for medical evaluation before exercise initiation, creating a potential barrier to adoption. The new American College of Spo...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000001331
更新日期:2017-10-01 00:00:00
abstract::Skeletal muscle is characterized by its ability to dynamically adapt to variable levels of functional demands. During periods of insufficient training stimulus, muscular detraining occurs. This may be characterized by a decreased capillary density, which could take place within 2--3 wk of inactivity. Arterial-venous o...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1097/00005768-200108000-00009
更新日期:2001-08-01 00:00:00
abstract:PURPOSE:The purpose of this study was to test the hypothesis that stretch-activated ion channel (SAC) function is essential for the repeated bout effect (RBE) in skeletal muscle. Specifically, we investigated if daily injections of streptomycin (a known SAC blocker) would abrogate the muscle's adaptive resistance to th...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e318187cffa
更新日期:2009-02-01 00:00:00
abstract:PURPOSE:We investigated the knee-extensor torque at which reoxygenation (inflow of arterial blood) during an isometric contraction stopped, whether this torque depended on maximal torque capacity (MTC), and whether there were differences among the synergists. METHODS:Isometric knee-extension torque was measured using ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/mss.0b013e31802dd3cc
更新日期:2007-03-01 00:00:00
abstract:PURPOSE:The purpose of this study was to determine whether increased intraluminal pressure is the damaging factor that reduces flow-mediated dilation (FMD) in young, healthy subjects after resistance exercise to maximal exertion. HYPOTHESIS:Attenuating the rise in brachial artery pressure during weight lifting by plac...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000001150
更新日期:2017-04-01 00:00:00
abstract:PURPOSE:The present longitudinal study assessed cardiorespiratory capacity and running economy of Olympic athletes over several decades to measure changes in fitness in an elite group during aging. METHODS:Twenty-six male runners training for the 1968 Olympics were recruited. HR, V˙O2max, ventilation, and running econ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000001407
更新日期:2018-01-01 00:00:00
abstract::The kinetics of gas exchange at the on-transient of exercise are appreciably slowed in older individuals. Eight older men (72 yr) completed 6 months of aerobic cycle training. Ventilation and gas exchange kinetics were determined at the onset of a below threshold (ventilatory threshold, V(E)T) square wave exercise fun...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1994-04-01 00:00:00
abstract:PURPOSE:Although several studies have shown that immune cells stimulated by in vitro stress are capable to produce neurotrophins, there is still no evidence whether physiological stress, such as exercise, can modulate the in vivo levels of brain-derived neurotrophic factor (BDNF) in peripheral blood mononuclear cells (...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e31825ab69b
更新日期:2012-10-01 00:00:00
abstract::Although no conclusive evidence exists to suggest that vitamin supplementation improves athletic performance in nutritionally adequate individuals, exercise may increase requirements for certain vitamins in individuals with marginal vitamin stores. This review summarizes results from recent research studies of vitamin...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1987-10-01 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:BACKGROUND:Extracellular vesicles (EV) are purported to mediate type 2 diabetes and CVD risk and development. Physical activity and a balanced diet reduce disease risk, but no study has tested the hypothesis that short-term interval (INT) training would reduce EV compared with continuous (CONT) exercise in adults with ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000002185
更新日期:2020-03-01 00:00:00
abstract::Physical inactivity has been linked to rates of obesity, diabetes, and heart disease through insulin resistance and other mechanisms. Although sedentary workplace environments have unintentionally contributed to the risk for chronic diseases, innovations in the workplace environment could potentially rectify this publ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000001679
更新日期:2018-10-01 00:00:00
abstract:INTRODUCTION:Although both humans and quadrupeds frequently coordinate breathing and limb movement during running, early studies in humans focused on how increased breathing flexibility in humans allowed for relaxed or even transient coordination during locomotion. This difference was used to explain why quadrupeds had...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e318248d907
更新日期:2012-07-01 00:00:00
abstract:PURPOSE:The increased physiological demand of pregnancy results in profound adaptation of the maternal cardiovascular system, reflected by greater resting cardiac output and left ventricular (LV) deformation. Whether the increased resting demand alters acute cardiac responses to exercise in healthy pregnant women is no...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000002554
更新日期:2020-11-03 00:00:00
abstract::For high-intensity muscular exercise, the time-to-exhaustion (t) increases as a predictable and hyperbolic function of decreasing power (P) or velocity (V ). This relationship is highly conserved across diverse species and different modes of exercise and is well described by two parameters: the "critical power" (CP or...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1249/MSS.0b013e3181d9cf7f
更新日期:2010-10-01 00:00:00
abstract:PURPOSE:The purpose of this investigation was to determine whether whole body composition could be estimated in tall individuals using summed measures from two partial DXA scans. METHODS:Using a pencil-beam DXA, a convenience sample of young individuals (N = 19) were scanned three times. Two partial scans of the upper...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000170077.87301.65
更新日期:2005-07-01 00:00:00
abstract:PURPOSE:The present study investigated the effects of three consecutive days of endurance training under conditions of low energy availability (LEA) on the muscle glycogen content, muscle damage markers, endocrine regulation, and endurance capacity in male runners. METHODS:Seven male long-distance runners (19.9 ± 1.1 ...
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.0000000000002098
更新日期:2020-01-01 00:00:00
abstract::Although low back pain (LBP) is a widespread and disabling health problem, there is a lack of evidence based medicine with respect to its treatment and rehabilitation. A major reason for this is the poor understanding of the underlying mechanisms of the LBP syndromes. In an attempt to fill this gap, the present review...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1097/00005768-200111000-00014
更新日期:2001-11-01 00:00:00