Abstract:
UNLABELLED:Although effects of workload and cadence on sagittal plane knee biomechanics in cycling have been widely studied, few studies have examined their impact on the frontal plane. PURPOSE:The purpose of this study was to investigate the effects of different workloads and cadences on knee sagittal and frontal plane biomechanics. METHODS:Eighteen healthy participants (age, 55.7 ± 11.0 yr) volunteered for this study. A motion analysis system and a custom instrumented pedal were used to collect five cycles of three-dimensional kinematics (240 Hz) and pedal reaction force (PRF, 1200 Hz) during 2 min of cycling in each of eight testing conditions, including five workload conditions of 0.5, 1, 1.5, 2, and 2.5 kg at 60 rpm, and three cadence conditions of 70, 80, and 90 rpm with 1-kg workload. Two one-way repeated measures analyses of variance were used to examine the influence of cadence and workload on selected variables (P < 0.05). RESULTS:Increased workloads with constant rpm caused an increased peak knee abduction moment from 5.82 to 14.36 N · m and peak knee extension moment from 11.61 to 37.16 N · m. Increased workloads also significantly increased peak medial and vertical PRF. Increased cadences at the constant workload had no effects on peak knee abduction moment but caused increased peak anterior and vertical PRF and peak knee flexion moment. CONCLUSIONS:The findings of this study indicate that increasing workload at constant cadence significantly increased peak knee abduction moment. Further study may be needed to demonstrate the efficacy of appropriate levels of workload and cadence in knee osteoarthritis and other populations with knee problems.
journal_name
Med Sci Sports Exercjournal_title
Medicine and science in sports and exerciseauthors
Fang Y,Fitzhugh EC,Crouter SE,Gardner JK,Zhang Sdoi
10.1249/MSS.0000000000000759subject
Has Abstractpub_date
2016-02-01 00:00:00pages
260-6issue
2eissn
0195-9131issn
1530-0315journal_volume
48pub_type
杂志文章,随机对照试验abstract:PURPOSE:There is interest in the potential long-term use of dietary supplementation with bovine colostrum to enhance exercise performance. The purpose of the present study was to determine the dose effects of bovine colostrum on cycling performance. METHODS:Forty-two competitive cyclists were randomly divided into thr...
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:10.1097/00005768-200207000-00020
更新日期:2002-07-01 00:00:00
abstract:PURPOSE:To determine whether the magnitude of improvement in athletic performance and the mechanisms driving these adaptations differ in relatively weak individuals exposed to either ballistic power training or heavy strength training. METHODS:Relatively weak men (n = 24) who could perform the back squat with proficie...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,随机对照试验
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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:PURPOSE:To evaluate the effects of a 12-wk period of aquatic training and subsequent detraining on health-related quality of life (HRQOL) and physical fitness in females with fibromyalgia. METHODS:Thirty-four females with fibromyalgia were randomly assigned into two groups: an exercise group, who exercised for 60 min ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,随机对照试验
doi:10.1249/01.mss.0b0138059aec4
更新日期:2007-07-01 00:00:00
abstract:PURPOSE:To study the effect of genetic factors, birth weight, early childhood growth, sport, hours of training, and pubertal status on the stature and body mass index (BMI) of children aged 9-13 participating in sports at a competitive level. METHODS:A total of 184 children (96 girls, 88 boys), competing in swimming, ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200010000-00006
更新日期:2000-10-01 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
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3182084562
更新日期:2011-07-01 00:00:00
abstract:UNLABELLED:Closed rupture of the flexor tendon sheath has been known to occur in the elite rock climbing population. However, only one study has investigated the prevalence of this entity. PURPOSE:To examine an elite climbing group in this country for the prevalence of pulley rupture and report on other commonly occur...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200008000-00002
更新日期:2000-08-01 00:00:00
abstract::This report demonstrates the effect of voluntary exercise in attenuating increases in heart rate (HR) caused by chronic stress in an animal model of stress-induced hypertension, the borderline hypertensive rat (BHR). Exercise training also protected against the hypertensive effects of stress in 16-wk-old, but not 10-w...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1987-02-01 00:00:00
abstract::Selective beta 1-receptor blockade with atenolol (1 mg X kg-1, i.v.) was used to determine the effect of partial exercise training on diastolic coronary resistance (DCR) during sub-maximal exercise. Seven conscious dogs were studied in the untrained (UT) and partially trained (PT) conditions. The conditioning regime c...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1987-08-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,多中心研究
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更新日期:2015-10-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
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更新日期:2008-07-01 00:00:00
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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:10.1097/00005768-199809000-00010
更新日期:1998-09-01 00:00:00
abstract:PURPOSE:To develop a protocol for isolating changes in aerodynamic and rolling resistances from field-based measures of power and velocity during level bicycling. METHODS:We assessed the effect of body position (hands on brake hoods vs drops) and tire pressure changes (414 vs 828 kPa) on aerodynamic and rolling resist...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3181fcb140
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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
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.MSS.0000064941.43869.4E
更新日期:2003-05-01 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
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abstract::Natural killer (NK) cells are highly influenced by physical exercise. The possible important mechanisms behind exercise-induced changes in NK cell function are cytokines, hyperthermia, and stress hormones, including catecholamines, growth hormone, cortisol, and beta-endorphins. Infusion studies mimicking stress hormon...
journal_title:Medicine and science in sports and exercise
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199811000-00015
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journal_title:Medicine and science in sports and exercise
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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::A 23-yr-old female body builder injured her right wrist while training. A correct diagnosis of pure distal radio-ulnar dislocation, ulnar volar, was made, and reduction was successfully carried out. After removal of plaster, the patient complained of wrist pain and clicking. Surgical exploration revealed a ruptured tr...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1990-04-01 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
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更新日期:2016-07-01 00:00:00
abstract:PURPOSE:Approximately 6500 high school football athletes are treated annually for exertional heat illness (EHI). In 2009, the National Athletic Trainers Association (NATA)-led Inter-Association Task Force (NATA-IATF) released preseason heat acclimatization guidelines to help athletes become accustomed to environmental ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
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更新日期:2014-01-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/mss.0b013e3180383d50
更新日期:2007-06-01 00:00:00
abstract:PURPOSE:This study evaluated the effect of Tai Chi Chuan (TCC) on the autonomic nervous modulation in older persons. METHODS:Twenty TCC practitioners and 20 normal controls were included in this study. The stationary state spectral heart rate variability (HRV) measures between TCC practitioners and normal controls, an...
journal_title:Medicine and science in sports and exercise
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更新日期:2003-12-01 00:00:00
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journal_title:Medicine and science in sports and exercise
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更新日期:2011-02-01 00:00:00
abstract:INTRODUCTION AND PURPOSE:Physical inactivity in postmenopausal women contributes to a rise in atherogenic risk factors associated with the metabolic syndrome. Although regular physical activity positively contributes to health, inactivity progressively increases with age. The Dose Response to Exercise in Women aged 45-...
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
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更新日期:2004-02-01 00:00:00
abstract:UNLABELLED:Ratings of perceived exertion (RPE) were developed to provide a subjective estimation of exercise intensity during exercise but are also used to produce exercise intensities and to report the intensity of completed exercise sessions. PURPOSE:To determine the relationship between RPE assessed before, during,...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
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更新日期:2009-03-01 00:00:00
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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.0000000000002122
更新日期:2020-01-01 00:00:00