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 recorded every 3 s during 4-h time blocks from 8:00 a.m.-8:00 p.m. Agreement among observers using the coding system was 91%. Using indirect calorimetry, calibration studies in the laboratory determined VO2 (ml.min-1.min-1) during each coded activity, and activities were categorized by intensity (low, medium, or high). Subjects were found to engage in activities of low intensity 77.1% of time and activities of high intensity 3.1% of time. The median duration of low and medium intensity activities was 6 s, of high intensity activities only 3 s with 95% lasting less than 15 s. Children engaged in very short bursts of intense physical activity interspersed with varying intervals of low and moderate intensity. These findings may be important for discovering how children's activity patterns under natural conditions influence physiological processes leading to growth and development. This study demonstrates the advantages of using an observational system that captures more than the intensity and frequency of children's activities to include duration and the length of intervals between activities of varying intensity.
journal_name
Med Sci Sports Exercjournal_title
Medicine and science in sports and exerciseauthors
Bailey RC,Olson J,Pepper SL,Porszasz J,Barstow TJ,Cooper DMdoi
10.1249/00005768-199507000-00012subject
Has Abstractpub_date
1995-07-01 00:00:00pages
1033-41issue
7eissn
0195-9131issn
1530-0315journal_volume
27pub_type
杂志文章abstract:PURPOSE:For ultra-endurance athletes, whose energy expenditure is likely to be at the extremes of human tolerance for sustained periods of time, there is increased concern regarding meeting energy needs. Due to the lack of data outlining the energy requirements of such athletes, it is possible that those participating ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200101000-00022
更新日期:2001-01-01 00:00:00
abstract:PURPOSE:This study examined the direct, moderating, and indirect effects of dispositional optimism on the prediction of, and athletes' responses to, injury. METHODS:A 2-yr longitudinal design was conducted with a baseline sample of 694 asymptomatic participants (389 men, 305 women; mean ± SD age = 19.17 ± 1.69 yr), 10...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e31826ea8e3
更新日期:2013-02-01 00:00:00
abstract:PURPOSE:Cycling to school is positively associated with aerobic fitness in Danish schoolchildren and adolescents. The aim of the present study was to determine whether a positive association exists between active travel and aerobic fitness in English schoolchildren, where cycling to school is rare. METHODS:Participant...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3181b11bdc
更新日期:2010-02-01 00:00:00
abstract:PURPOSE:The purpose of this study was twofold: (a) to measure the effects of temporal parameters on both ball velocity and upper limb joint kinetics to identify pathomechanical factors during the tennis serve and (b) to validate these pathomechanical factors by comparing injured and noninjured players. METHODS:The ser...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e318299ae3b
更新日期:2013-11-01 00:00:00
abstract:PURPOSE:Physical activity questionnaires (PAQs) are considered the most cost-efficient method to estimate total energy expenditure (TEE) in epidemiological studies. However, relatively few PAQs have been validated using doubly labeled water (DLW) in women or in samples with diverse ethnic backgrounds. This study was co...
journal_title:Medicine and science in sports and exercise
pub_type: 临床试验,杂志文章
doi:10.1097/00005768-200111000-00024
更新日期:2001-11-01 00:00:00
abstract::The cell-to-cell lactate shuttle was introduced in 1984 and has been repeatedly supported by studies using a variety of experimental approaches. Because of its large mass and metabolic capacity, skeletal muscle is probably the major component of the lactate shuttle in terms of both production and consumption. Muscles ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1249/MSS.0b013e31815fa580
更新日期:2008-03-01 00:00:00
abstract:PURPOSE:Compare three published methods of quantifying physical activity (total activity, peak strain, and bone-loading exposure (BLE) scores) and identify their associations with areal bone mineral density (aBMD), volumetric BMD (vBMD), and bone strength. METHODS:Postmenopausal women (N = 239; mean age: 53.8 yr) from...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,多中心研究
doi:10.1249/mss.0b013e318155a7fe
更新日期:2007-12-01 00:00:00
abstract:PURPOSE:To examine the relationship between variable lower-limb coordination and shoulder joint kinetics and kinematics in the high-performance flat first serve in tennis. METHODS:Three-dimensional data describing three flat serve (FS) techniques, each executed with varying lower-limb involvement: foot-up (FU), foot-b...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/mss.0b013e31815c6d61
更新日期:2008-02-01 00:00:00
abstract::A variety of physiological responses, classified as local or central factors, have been suggested as providing the primary input for perception of effort during exercise. The potency of these responses as perceptual cues, however, has seldom been addressed in terms of relevant modifying variables such as exercise inte...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:
更新日期:1981-01-01 00:00:00
abstract::Data obtained from 16-mm film of world caliber Olympic weight lifters performing at major competitions were analyzed to study energy changes during body segment and barbell movements, energy transfer to the barbell, and energy transfer between segments during the lifting movements contested. Determination of barbell a...
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 purpose of the present investigation was to examine the wet suit effect on 8 swimmers and 8 triathletes. For swimmers, the performances of a 400-m swim with and without wet suit were not statistically different (4 min 12.5 +/- 8 s vs 4 min 13.9 +/- 4 s) while for triathletes the swim times were reduced by 19 s (4 ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1995-04-01 00:00:00
abstract:PURPOSE:To assess the validity of the new Actical accelerometer step count function. METHODS:Actical step counts were compared according to two criterion standards. 1) Eight Acticals were assessed using a mechanical shaker table under six different testing conditions. 2) Thirty-eight volunteers (aged 9-59 yr) wore eig...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/mss.0b013e3804ec4e9
更新日期:2007-07-01 00:00:00
abstract::This symposium is concerned with the use of resistive exercise in cardiac and coronary prone populations. In the past, these populations have been refrained from resistive exercise. However, recent studies suggest that this form of exercise is safe and has favorable effects on physical fitness, cardiac risk factors su...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1989-12-01 00:00:00
abstract::MRI is an excellent noninvasive method of diagnosing difficult shoulder problems. Although usually not needed for classic primary impingement syndrome or clinically obvious rotator cuff tears, MRI may be helpful in diagnosing secondary causes of impingement or in some cases involving partial rotator cuff tears. Some s...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1097/00005768-199804001-00002
更新日期:1998-04-01 00:00:00
abstract::Although hyponatremia (HN) has been reported among endurance athletes, its etiology often remains uncertain and of great interest to clinicians and physiologists. This case report presents physiologic evidence regarding the etiology and development of HN during exercise in the heat. A 21-yr-old male volunteer (K.G.) u...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1993-05-01 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
pub_type: 杂志文章
doi:
更新日期:1993-12-01 00:00:00
abstract:PURPOSE:To determine the reliability and validity of the School Health Action, Planning and Evaluation System (SHAPES) physical activity questionnaire, a machine-readable questionnaire designed to collect data from all students in a school from grades 6 to 12 and to provide feedback to the school for planning and evalu...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000227539.58916.35
更新日期:2006-09-01 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::The purpose of this study was to assess the relationship between the isometric and isokinetic peak torque (PT) (speed of movement 0, 60, and 180 degrees.s-1) and the peak torque acceleration energy (PTAE) and average power (AP) of multiple contractions (180 degrees.s-1) of the quadriceps and hamstrings in 38 patients ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1989-06-01 00:00:00
abstract::Knee injuries continue to present a complex set of clinical problems. The answers to these problems have recently been redefined by the application of sophisticated biomechanical research methods to the study of knee ligaments and joint function. This manuscript reviews contributions which our laboratory has made to t...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/00005768-198410000-00002
更新日期:1984-10-01 00:00:00
abstract:PURPOSE:The objective of this study is to determine the effect of body mass index (BMI) on level of agreement between six previously established prediction equations for three commonly used accelerometers to predict summary measures of energy expenditure (EE) in youth. METHODS:One hundred and thirty-one youth between ...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e318267b8f1
更新日期:2012-12-01 00:00:00
abstract:INTRODUCTION:Physical activity may affect health via DNA methylation. The epigenetic influences of sedentary behaviors such as television viewing are unknown. We performed a genomewide study of DNA methylation in peripheral blood in relation to physical activity and television viewing time. METHODS:DNA methylation was...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000001827
更新日期:2019-03-01 00:00:00
abstract:PURPOSE:Apnea divers hyperinflate the lung by taking a deep breath followed by glossopharyngeal insufflation. The maneuver can lead to symptomatic arterial hypotension. We tested the hypotheses that glossopharyngeal insufflation interferes with cardiac function further reducing cardiac output (CO) using cardiac magneti...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e31821ff294
更新日期:2011-11-01 00:00:00
abstract:PURPOSE:To evaluate long-term susceptibility to subsequent serious exertional heat illness (EHI) in military recruits who suffered exertional heat illness during basic training. METHODS:We identified Marine Corps members who completed at least 6 months of military service and suffered EHI treated as outpatients (N = 8...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200109000-00004
更新日期:2001-09-01 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:This study examined whether plasma total glutathione levels could explain the intersubject variability in the creatine kinase (CK) response to eccentric exercise. We hypothesized that the increase in plasma CK activity after eccentric exercise would be lower for individuals with low plasma total glutathione (<2...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.MSS.0000069553.47739.36
更新日期:2003-06-01 00:00:00
abstract::A decrease in hepatic lactate dehydrogenase (LDH) activity following endurance training has been a consistent observation. In the present study, we sought to determine whether the training-induced decrease in hepatic LDH activity (pyruvate = substrate) was associated with a shift in the isoenzyme profile and/or altera...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1995-04-01 00:00:00
abstract:PURPOSE:Physical exercise or hypoxic exposure influences hemorheology and acid-base homeostasis. Band 3 protein in erythrocytes modulates cells' rheological properties and anion transport ability. This study investigated how cycling aerobic interval training (AIT) and moderate continuous training (MCT) affect the rheol...
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.0000000000000730
更新日期:2016-01-01 00:00:00
abstract:PURPOSE:The rapidly increasing incidence of Lyme disease has become a serious public health problem. Persistent symptoms of Lyme disease occur in over 40% of the 300,000 new cases diagnosed annually in the United States and often include debilitating musculoskeletal pain, fatigue, and poor health-related quality of lif...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000000683
更新日期:2015-11-01 00:00:00
abstract:PURPOSE:To determine the prevalence of full-thickness focal chondral defects in the athlete's knee. METHODS:We conducted a systematic review of multiple databases, evaluating studies of the prevalence of articular cartilage defects in athletes. Because of the heterogeneity of data, a meta-analysis could not be perform...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1249/MSS.0b013e3181d9eea0
更新日期:2010-10-01 00:00:00