Abstract：
:Stress fractures (SF) are one of the most common and potentially serious overuse injuries. PURPOSE:This study aimed to develop a computational biomechanical model of strain in human tibial bone that will facilitate better understanding of the pathophysiology of SF. METHODS:The MRI of a healthy, young male was used for full anatomical segmentation of the calf tissues, which considered hard-soft tissues biomechanical interactions. From the undeformed coronal MR images, the geometry of bones, muscles, connecting ligaments, and fat were reconstructed in three dimensions and meshed to a finite element model. A force that simulated walking was applied on the tibial plateaus. The model was then analyzed for strains in the tibia under various conditions: unloaded walking, walking with a load equivalent to 30% of bodyweight, and walking under conditions of muscular fatigue. In addition, the effect of tibia robustness on strain was analyzed. RESULTS:The model showed that the tibia is mostly loaded by compression, with maximal strains detected in the distal anterior surface: 1241 and 384 microstrain, compressive and tensile, respectively. Load carriage resulted in ~30% increase in maximal effective strains. Muscle fatigue has a complex effect; fatigued calf muscles (soleus) reduced the maximal effective strains up to 9%, but fatigued thigh muscles increased those strains by up to 3%. It had also been shown that a slender tibia is substantially prone to higher maximal effective strains compared with an average (22% higher) or robust tibia (39% higher). CONCLUSIONS:Thigh muscle fatigue, load carriage, and a slender tibia were detected as factors that may contribute to the development of SF. The methodology presented here is a novel tool for investigating the pathophysiology of SF.
journal_name
Med Sci Sports Exercjournal_title
Medicine and science in sports and exerciseauthors
Hadid A,Epstein Y,Shabshin N,Gefen Adoi
10.1249/MSS.0000000000001628subject
Has Abstractpub_date
2018-09-01 00:00:00pages
1827-1836issue
9eissn
0195-9131issn
1530-0315journal_volume
50pub_type
杂志文章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
pub_type： 临床试验,杂志文章
doi：
更新日期：1995-06-01 00:00:00
abstract：INTRODUCTION:Muscle force production is usually impaired in people with spinal cord injury (SCI). The use of high-intensity neuromuscular electrical stimulation (NMES) strength training can help promote metabolically active lean muscle mass and, thus, increase muscle mass and improve physical health and quality of life...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0000000000001637
更新日期：2018-09-01 00:00:00
abstract：PURPOSE:This study investigated the effects of the menstrual cycle on prolonged exercise performance both in temperate (20°C, 45% relative humidity) and hot, humid (32°C, 60% relative humidity) conditions. METHODS:For each environmental condition, 12 recreationally active females were tested during the early follicula...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0b013e3182656f13
更新日期：2012-11-01 00:00:00
abstract：PURPOSES:To validate the energy expenditure estimated from The Minnesota Leisure Time Physical Activity Questionnaire (MLTPAQ) with total energy expenditure (TEE) measured by doubly labeled water (DLW), and to present and examine the validity of an extended version of the MLTPAQ with additional questions about inactivi...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/01.MSS.0000093608.95629.85
更新日期：2003-11-01 00:00:00
abstract：UNLABELLED:Theoretically, critical torque (CT) is the maximal isometric torque that can be maintained without fatigue, and anaerobic work capacity (AWC) is the total "isometric work" associated with stored energy sources within the muscle. PURPOSE:The purpose of this study was twofold: 1) to determine whether there we...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0b013e3181ab8cc0
更新日期：2009-12-01 00:00:00
abstract：PURPOSE:To date, no study has examined the synergistic effects of a nutrition and combination of aerobic and strength training (CAST) on both adiposity and metabolic parameters in overweight Latina adolescent females. The goal was to assess if a 16-wk nutrition plus CAST pilot study had stronger effects on reducing adi...
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.0b013e31819b6aea
更新日期：2009-07-01 00:00:00
abstract：PURPOSE:This study aimed to examine the associations between participation frequency in physical education (PE) classes and objective measures of physical activity (PA) and sedentary behavior (SB) in children from 12 countries at different levels of development. METHODS:This multinational, cross-sectional study includ...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章,多中心研究
doi：10.1249/MSS.0000000000001524
更新日期：2018-05-01 00:00:00
abstract：INTRODUCTION:The application of an autologous plasma rich in growth factors is beneficial in restoring connective tissues, as shown by clinical evidence in oral surgery and more recently in arthroscopic anterior cruciate ligament reconstruction and two cases of ruptured Achilles tendon in professional athletes. This is...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/01.MSS.0000089344.44434.50
更新日期：2003-10-01 00:00:00
abstract：OBJECTIVE:The present study evaluated the effects of an acute bout of moderate-intensity treadmill walking on aspects of cognitive control underlying successful academic achievement. METHODS:The study used a within-subjects counterbalanced design with a sample of 36 preadolescent children. Cognitive performance was as...
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.0b013e318258bcd5
更新日期：2012-10-01 00:00:00
abstract：PURPOSE:Walking is likely to contribute substantially to nonexercise activity thermogenesis. The Tracmor triaxial accelerometer system (Maastricht, The Netherlands) is the most widely validated system for detecting body movement in free-living subjects. The aim of this study was to validate the Tracmor triaxial acceler...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1097/00005768-200109000-00024
更新日期：2001-09-01 00:00:00
abstract：:The aim of this study was to determine the energy expenditure of a 1-h noncontact boxing training session and to compare these results with the energy expenditure of a more conventional recreational activity such as running. Eight healthy males, accustomed to noncontact boxing training, were recruited for the study. S...
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：10.1097/00005768-199712000-00016
更新日期：1997-12-01 00:00:00
abstract：:Myocardial crypts are extensions of blood signal penetrating the compact myocardium and are considered in literature as either a distinctive cardiac magnetic resonance (CMR) imaging marker for hypertrophic cardiomyopathy or as benign congenital malformations. What if CMR reveals a myocardial crypt in the presence of a...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0000000000000406
更新日期：2015-02-01 00:00:00
abstract：PURPOSE:Cardiopulmonary exercise testing (CPX) provides valuable clinical information, including peak ventilation (V˙Epeak), which has been shown to have diagnostic and prognostic value in the assessment of patients with underlying pulmonary disease. This report provides reference standards for V˙Epeak derived from CPX...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0000000000001740
更新日期：2018-12-01 00:00:00
abstract：UNLABELLED:Hiking is a recreational activity shown to offer significant positive effects on the human body. However, walking downhill and external load carriage have both been shown to increase the risk of musculoskeletal pain and injury. The use of hiking poles has been demonstrated to be successful in reducing forces...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/01.mss.0000240328.31276.fc
更新日期：2007-01-01 00:00:00
abstract：:Muscle fatigue has been studied with a variety approaches, tools and technologies. The foci of these studies have ranged tremendously, from molecules to the entire organism. Single cell and animal models have been used to gain mechanistic insight into the fatigue process. The theme of this review is the concept that t...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章,评审
doi：10.1249/MSS.0000000000001052
更新日期：2016-11-01 00:00:00
abstract：UNLABELLED:Physically active classroom lessons have been found to increase on-task behavior in children. Given that physical activity has been associated with an increased time on task (TOT) and that overweight children take fewer steps than normal weight children do, it was expected that benefits of the physical activ...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0b013e3181a61495
更新日期：2009-10-01 00:00:00
abstract：PURPOSE:Physical fitness and physical activity tracking data enhance our understanding as to when children settle into their long-term exercise and fitness patterns and, therefore. provide insight as to when programs focusing on preventing sedentary adults behaviors should be initiated. METHODS:In this paper, the trac...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1097/00005768-200007000-00011
更新日期：2000-07-01 00:00:00
abstract：PURPOSE:To examine the effects of prolonged systemic administration of diclofenac sodium (Voltaren), a nonsteroidal anti-inflammatory drug, on objective indices of exercise-induced muscle damage in humans. METHODS:Fifty-four volunteers (mean age, 26.4 yr; range, 18-35) participated in this randomized double-blind, pla...
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：10.1097/00005768-200007000-00001
更新日期：2000-07-01 00:00:00
abstract：PURPOSES:To compare the claudication distances between men and women patients with peripheral arterial disease (PAD), and to determine whether sex differences in claudication pain persisted after controlling for potential confounders such as demographic, functional, and physiological measures. METHODS:A total of 488 m...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1097/00005768-200211000-00001
更新日期：2002-11-01 00:00:00
abstract：PURPOSE:Dual-energy x-ray absorptiometry (DXA) is becoming a popular tool to measure body composition in athletes, owing to its ease of operation and comprehensive analysis of body composition. This study represents the first systematic investigation of the reliability of DXA measurements of body composition in trained...
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.0b013e318228b60e
更新日期：2012-01-01 00:00:00
abstract：PURPOSE:Recent literature suggests that subconcussive impacts may influence cognitive functioning across the life span. These effects are suggested to manifest as functional and possibly structural changes. Head impact biomechanics during American football have been characterized from the high school to professional le...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0b013e3182798758
更新日期：2013-04-01 00:00:00
abstract：:Participation in sports in on the increase; this article addresses the intersection of sports and infectious diseases. Some infections occur with increased incidence in sports; others have an increased impact in that setting. Addressed in this article are issues of diagnosis, prevention, and management of many of thes...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章,评审
doi：10.1097/00005768-200007001-00008
更新日期：2000-07-01 00:00:00
abstract：:Cardiovascular responses were obtained during cycling with graded levels of lower-body positive pressure (LBPP) applied to the exercising limbs. Seven men performed four incremental work rate (25 W.min-1) exercise (IWREx) tests to their limit of tolerance while exposed to 0, 15, 30, or 45 Torr LBPP. They also performe...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/00005768-199406000-00008
更新日期：1994-06-01 00:00:00
abstract：PURPOSE:Investigate hemodynamic responses of resistance exercise (RE) with moderate load (i.e., international guidelines for RE of patients) versus RE with high load in patients with coronary artery disease (CAD). METHODS:Medically stable male (n = 11) and female patients (n = 4) treated with PCI or percutaneous coron...
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.0000000000000811
更新日期：2016-04-01 00:00:00
abstract：PURPOSE:Maternal obesity is known to predispose the offspring to impaired glucose metabolism and obesity associated with low-grade inflammation and hypothalamic dysfunction. Because preventive approaches in this context are missing to date, we aimed to identify molecular mechanisms in the offspring that are affected by...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0000000000000835
更新日期：2016-05-01 00:00:00
abstract：PURPOSE:The main purpose of the present study was to measure the total oxygen consumed, accumulation of blood metabolites, and performance during alternating intensity exercise before and after a period of creatine (Cr) loading in well-trained humans. METHODS:Fourteen males were randomly assigned to two groups of seve...
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：10.1097/00005768-200002000-00018
更新日期：2000-02-01 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：BACKGROUND:Recent work has identified deficits in dual-task gait balance control for up to 2 months after adolescent concussion; however, how resumption of preinjury physical activities affects recovery is unknown. PURPOSE:The objective of this study is to examine how return to activity (RTA) affects recovery from con...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1249/MSS.0000000000000462
更新日期：2015-04-01 00:00:00
abstract：PURPOSE:The purpose of this study was to compare architectural characteristics of leg muscles of sprinters and distance runners. METHODS:Skeletal muscle architectural characteristics were studied in 23 elite male 100-m sprinters (SPR, 10.0-10.9 s for 100 m), 24 elite male distance runners (DR, 13.5-14.5 min for 5000 m...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1097/00005768-200006000-00014
更新日期：2000-06-01 00:00:00
abstract：PURPOSE:To compare four different methods of measuring physical activity (PA) in adult women under free-living conditions. METHODS:Twelve women participated in a 7-d period during which PA was assessed via self-report, accelerometry and step-counting. Subjects wore at the waist a Tritrac-R3D accelerometer, a Computer ...
journal_title：Medicine and science in sports and exercise
pub_type： 杂志文章
doi：10.1097/00005768-200007000-00021
更新日期：2000-07-01 00:00:00
