The effects of anabolic steroids on myocardial structure and cardiovascular fitness.

abstract：:The purpose of this study was to describe the body composition of adolescent and young adult ballet dancers using total body electrical conductivity (TOBEC). We studied 112 female and 33 male dancers. The mean ages were 15.0 +/- 2.0 and 18.7 +/- 3.1 yr for females and males, respectively. The mean percent body fat (PB...

journal_title：Medicine and science in sports and exercise

authors： Hergenroeder AC,Fiorotto ML,Klish WJ

更新日期：1991-05-01 00:00:00

abstract：PURPOSE:This study examines the usefulness of complementing accelerometry-based physical activity measurement with spatial data from portable global positioning system (GPS) units to determine where physical activity occurs. METHODS:First, using the geographic distribution of data points and Bland-Altman plots, we exa...

journal_title：Medicine and science in sports and exercise

authors： Rodríguez DA,Brown AL,Troped PJ

更新日期：2005-11-01 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

authors： Wakeling JM,Pascual SA,Nigg BM

更新日期：2002-09-01 00:00:00

abstract：PURPOSE:The objective of this study is to determine whether individuals with type 1 diabetes exhibit impairments in local and whole-body heat loss responses that could affect core temperature regulation during exercise in the heat compared with matched, nondiabetic individuals. METHODS:Twelve otherwise healthy individ...

journal_title：Medicine and science in sports and exercise

authors： Stapleton JM,Yardley JE,Boulay P,Sigal RJ,Kenny GP

更新日期：2013-09-01 00:00:00

abstract：PURPOSE:Increased serum testosterone (TST) occurs in response to resistance exercise and is associated with increased muscle mass. However, the effects of elevated TST and sequential resistance exercise bouts on androgen receptor (AR) expression in humans are not well known. This study examined three sequential bouts o...

journal_title：Medicine and science in sports and exercise

authors： Willoughby DS,Taylor L

更新日期：2004-09-01 00:00:00

abstract：INTRODUCTION:Cardiac magnetic resonance (CMR) late gadolinium enhancement (LGE) and T1 mapping techniques enable the quantification of focal and diffuse myocardial LGE, respectively. Studies have shown evidence of fibrosis in middle-age athletes, but not relative to physically active (PA) adults who perform recommended...

journal_title：Medicine and science in sports and exercise

authors： Banks L,Altaha MA,Yan AT,Dorian P,Konieczny K,Deva DP,LA Gerche A,Akhavein F,Bentley RF,Connelly KA,Goodman JM

更新日期：2020-12-01 00:00:00

abstract：:Twelve 9- to 12-year-old children (6 boys, 6 girls) performed four exercise-in-heat (35 degrees C, 45% RH) trials which differed in the composition of the fluids they drank. In each trial, subjects cycled for one 20-min and two 15-min bouts at 50% peak VO2 with 10-min rest periods in between. In a fourth bout, they cy...

journal_title：Medicine and science in sports and exercise

authors： Meyer F,Bar-Or O,MacDougall D,Heigenhauser GJ

更新日期：1995-06-01 00:00:00

abstract：PURPOSE:To investigate the use of Tritrac accelerometers to measure energy expenditure (EE) of various activities for women in the field setting, as compared with portable indirect calorimetry. METHODS:Twenty women (age 20-29) performed a choreographed routine of six activities (walking, jogging, stair climbing, walki...

journal_title：Medicine and science in sports and exercise

authors： Campbell KL,Crocker PR,McKenzie DC

更新日期：2002-10-01 00:00:00

abstract：PURPOSE:The purpose of this study is to examine whether performance supercompensation during taper is maximized in endurance athletes after experiencing overreaching during an overload training (OT) period. METHODS:Thirty-three trained male triathletes were assigned to either OT (n = 23) or normal training groups (n =...

journal_title：Medicine and science in sports and exercise

authors： Aubry A,Hausswirth C,Louis J,Coutts AJ,LE Meur Y

更新日期：2014-09-01 00:00:00

abstract：:To determine whether a 13C-bicarbonate, isotope dilution technique could be used to estimate relative changes in energy expenditure of leisure activities of short duration, we studied eight adolescents who performed the following activities: watching television (120 min); playing a stringed instrument (60 min plus 60 ...

journal_title：Medicine and science in sports and exercise

authors： Horswill CA,Zipf WB,Kien CL

更新日期：1997-09-01 00:00:00

abstract：:Energy expenditure during bicycling on flat terrain depends predominantly on air resistance, which is a function of total frontal area (bicycle and rider), coefficient of drag, and air speed. Body position on the bicycle may affect energy expenditure by altering either frontal area or coefficient of drag. In this stud...

journal_title：Medicine and science in sports and exercise

authors： Ryschon TW,Stray-Gundersen J

更新日期：1991-08-01 00:00:00

abstract：:The purpose of this study was to determine whether the magnitude of the activation force, defined as the force that must be applied to the load cell in order to activate the resistance arm of an isokinetic dynamometer, affected knee extensor torques. Twenty-four healthy female subjects performed resisted knee extensio...

journal_title：Medicine and science in sports and exercise

authors： Kramer JF,Vaz MD,Hakansson D

更新日期：1991-02-01 00:00:00

abstract：PURPOSE:The purpose of this study was to examine and quantify the effect of repeated driving stints on the physiologic, metabolic, and hormonal responses of three professional endurance driver-athletes. METHODS:Core body temperature, HR, and physiological strain index were recorded during the Rolex 24 Hours of Daytona...

journal_title：Medicine and science in sports and exercise

authors： Potkanowicz ES,Ferguson DP,Greenshields JT

更新日期：2020-09-01 00:00:00

abstract：PURPOSE:The effects of chronic exercise training on the expression of heat shock protein (HSP) in skeletal muscle of senescent animals are unknown. Therefore, the purpose of this study was to investigate the effects of chronic exercise training on skeletal muscle HSP expression in both young and old rats. METHODS:Youn...

journal_title：Medicine and science in sports and exercise

authors： Naito H,Powers SK,Demirel HA,Aoki J

更新日期：2001-05-01 00:00:00

abstract：:A primary goal of studies of successful aging is to identify the modifiable factors related to the plasticity of higher physical function; however, little is known about the relationship between habitual physical activity (especially that of lower- to moderate-intensity) and the maintenance of day-to-day functioning i...

journal_title：Medicine and science in sports and exercise

authors： DiPietro L

更新日期：1996-05-01 00:00:00

abstract：:Acute and chronic positive mood changes have been said to occur with running and jogging. It has been suggested that endogenous substances with opioid activity (endorphins) may serve as modulators of mood. The authors report experiments in which mood changes associated with long-distance running were measured by pre- ...

journal_title：Medicine and science in sports and exercise

authors： Markoff RA,Ryan P,Young T

更新日期：1982-01-01 00:00:00

abstract：:We compared the aortic-cardiac baroreflex sensitivity in eight average fit (AF: VO2max = 44.7 +/- 1.3 ml.kg-1 x min-1) and seven high fit (HF: VO2max = 64.1 +/- 1.7 ml.min-1 x kg-1) healthy young men during hypotension elicited by steady state sodium nitroprusside (SN) infusion. During SN mean arterial pressure (MAP) ...

journal_title：Medicine and science in sports and exercise

authors： Shi X,Crandall CG,Potts JT,Williamson JW,Foresman BH,Raven PB

更新日期：1993-09-01 00:00:00

abstract：:Pyruvate and dihydroxyacetone are three carbon compounds that when infused directly into the blood or taken orally produce strong metabolic effects. When chronically fed to animals as part of their diet, pyruvate plus dihydroxyacetone reduce the rate of weight gain and body fat content during growth. These alterations...

journal_title：Medicine and science in sports and exercise

authors： Ivy JL

更新日期：1998-06-01 00:00:00

abstract：PURPOSE:To optimize endurance cycling performance, it is important to maximize efficiency. Power-measuring cranks and force-sensing pedals can be used to determine the mechanical effectiveness of cycling. From both a coaching and basic science perspective, it is of interest if a mechanically effective pedaling techniqu...

journal_title：Medicine and science in sports and exercise

authors： Korff T,Romer LM,Mayhew I,Martin JC

更新日期：2007-06-01 00:00:00

abstract：PURPOSE:Evidence suggests that female adolescents and those living in urban environments may have lower physical activity (PA) levels compared with their peers. Yet few studies report PA for urban adolescent females, and there is no consensus regarding potential causes for low PA in this subgroup. We examined PA levels...

journal_title：Medicine and science in sports and exercise

authors： Rockette-Wagner B,Hipwell AE,Kriska AM,Storti KL,McTigue KM

更新日期：2017-04-01 00:00:00

abstract：PURPOSE:The goal of this study was to explore the effect of lifelong aerobic exercise (i.e., chronic training) on skeletal muscle substrate stores (intramyocellular triglyceride [IMTG] and glycogen), skeletal muscle phenotypes, and oxidative capacity (ox), in older endurance-trained master athletes (OA) compared with n...

journal_title：Medicine and science in sports and exercise

authors： Dubé JJ,Broskey NT,Despines AA,Stefanovic-Racic M,Toledo FG,Goodpaster BH,Amati F

更新日期：2016-03-01 00:00:00

abstract：:Anaerobic threshold (AT) and Vo2max were determined by automated analysis for 25 members of the 1980 U.S. Olympic Rowing Team during a progressive rowing ergometer exercise to exhaustion. Heart rates and power outputs were also measured to gauge severity of the exercise and to compare with metabolic data. Power increm...

journal_title：Medicine and science in sports and exercise

authors： Mickelson TC,Hagerman FC

更新日期：1982-01-01 00:00:00

abstract：PURPOSE:The objective of this study is to test the feasibility and impact of a 10-wk after-school exercise program for children with attention deficit hyperactivity disorder and/or disruptive behavior disorders living in an urban poor community. METHODS:Children were randomized to an exercise program (n = 19) or a com...

journal_title：Medicine and science in sports and exercise

authors： Bustamante EE,Davis CL,Frazier SL,Rusch D,Fogg LF,Atkins MS,Marquez DX

更新日期：2016-07-01 00:00:00

abstract：PURPOSE:High school cross-country runners have a high incidence of injury, particularly at the shin and knee. An increased step rate during running has been shown to reduce impact forces and loading of the lower extremity joints. The purpose of this prospective study was to examine step rate as a risk factor for injury...

journal_title：Medicine and science in sports and exercise

authors： Luedke LE,Heiderscheit BC,Williams DS,Rauh MJ

更新日期：2016-07-01 00:00:00

abstract：PURPOSE:This study aimed to determine the effect of acute exercise on the proliferation and expression of activation markers on T-lymphocytes. METHODS:Seventeen well-trained male endurance runners completed 60 min of treadmill running at 95% of ventilatory threshold and a resting, no exercise, control session at the s...

journal_title：Medicine and science in sports and exercise

authors： Green KJ,Rowbottom DG,Mackinnon LT

更新日期：2003-04-01 00:00:00

abstract：:In this study the gross efficiency of swimming was determined in a group of male (N = 6) and female (N = 4) competitive swimmers. The gross efficiency is defined as the ratio of the power output (W) to the power input (W). In a range of swimming velocities (0.95-1.6 m.s-1), the power input (rate of energy expenditure,...

journal_title：Medicine and science in sports and exercise

authors： Toussaint HM,Knops W,De Groot G,Hollander AP

更新日期：1990-06-01 00:00:00

abstract：:The objective of this study was to design and validate a working tool for the objective evaluation of daily energy expenditure (DEE) by means of a simple, noninvasive method: the QAPSE (Saint-Etienne Physical Activity Questionnaire), a questionnaire about physical activity (PA) over a period of 7 d (168 h). This eight...

journal_title：Medicine and science in sports and exercise

authors： Berthouze SE,Minaire PM,Chatard JC,Boutet C,Castells J,Lacour JR

更新日期：1993-12-01 00:00:00

abstract：:Regression analysis is often used to demonstrate associations among variables believed to be biologically related. Failure to demonstrate a "significant" relationship may be due to two factors: 1) the variables are truly unrelated, or 2) a relationship exists but goes undetected due to inadequate statistical power. In...

journal_title：Medicine and science in sports and exercise

authors： Sharp DS,Gahlinger PM

更新日期：1988-12-01 00:00:00

abstract：PURPOSE:The purpose of this study was to measure noninvasively the absolute concentrations of muscle adenosine triphosphate [ATP], phosphocreatine [PCr], inorganic phosphate (Pi), and glycogen [Gly] of elite soccer players. METHODS:Magnetic resonance spectroscopy (31P- and 13C-MRS) was used to measure the concentratio...

journal_title：Medicine and science in sports and exercise

authors： Rico-Sanz J,Zehnder M,Buchli R,Kühne G,Boutellier U

更新日期：1999-11-01 00:00:00

abstract：PURPOSE:To comprehensively quantify through daily, serial measures changes in knee laxity as a function of changing sex-hormone levels across one complete menstrual cycle. METHODS:Twenty-five females, 18 - 30 yr, body mass index < or = 30, who reported normal menstrual cycles (28-32 d) over the past 6 months participa...

journal_title：Medicine and science in sports and exercise

authors： Shultz SJ,Kirk SE,Johnson ML,Sander TC,Perrin DH

更新日期：2004-07-01 00:00:00