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Medicine and Science in Sports and Exercise | 2007

Physical Activity and Public Health Updated Recommendation for Adults From the American College of Sports Medicine and the American Heart Association

William L. Haskell; I-Min Lee; Russell R. Pate; Kenneth E. Powell; Steven N. Blair; Barry A. Franklin; Caroline A. Macera; Gregory W. Heath; Paul D. Thompson; Adrian Bauman

SUMMARY In 1995 the American College of Sports Medicine and the Centers for Disease Control and Prevention published national guidelines on Physical Activity and Public Health. The Committee on Exercise and Cardiac Rehabilitation of the American Heart Association endorsed and supported these recommendations. The purpose of the present report is to update and clarify the 1995 recommendations on the types and amounts of physical activity needed by healthy adults to improve and maintain health. Development of this document was by an expert panel of scientists, including physicians, epidemiologists, exercise scientists, and public health specialists. This panel reviewed advances in pertinent physiologic, epidemiologic, and clinical scientific data, including primary research articles and reviews published since the original recommendation was issued in 1995. Issues considered by the panel included new scientific evidence relating physical activity to health, physical activity recommendations by various organizations in the interim, and communications issues. Key points related to updating the physical activity recommendation were outlined and writing groups were formed. A draft manuscript was prepared and circulated for review to the expert panel as well as to outside experts. Comments were integrated into the final recommendation. PRIMARY RECOMMENDATION To promote and maintain health, all healthy adults aged 18 to 65 yr need moderate-intensity aerobic (endurance) physical activity for a minimum of 30 min on five days each week or vigorous-intensity aerobic physical activity for a minimum of 20 min on three days each week. [I (A)] Combinations of moderate- and vigorous-intensity activity can be performed to meet this recommendation. [IIa (B)] For example, a person can meet the recommendation by walking briskly for 30 min twice during the week and then jogging for 20 min on two other days. Moderate-intensity aerobic activity, which is generally equivalent to a brisk walk and noticeably accelerates the heart rate, can be accumulated toward the 30-min minimum by performing bouts each lasting 10 or more minutes. [I (B)] Vigorous-intensity activity is exemplified by jogging, and causes rapid breathing and a substantial increase in heart rate. In addition, every adult should perform activities that maintain or increase muscular strength and endurance a minimum of two days each week. [IIa (A)] Because of the dose-response relation between physical activity and health, persons who wish to further improve their personal fitness, reduce their risk for chronic diseases and disabilities or prevent unhealthy weight gain may benefit by exceeding the minimum recommended amounts of physical activity. [I (A)]


Medicine and Science in Sports and Exercise | 2000

Compendium of physical activities: an update of activity codes and MET intensities.

Barbara E. Ainsworth; William L. Haskell; Melicia C. Whitt; Melinda L. Irwin; Ann M. Swartz; Scott J. Strath; William L. O'brien; David R. Bassett; Kathryn H. Schmitz; Patricia O. Emplaincourt; David R. Jacobs; A. Leon

We provide an updated version of the Compendium of Physical Activities, a coding scheme that classifies specific physical activity (PA) by rate of energy expenditure. It was developed to enhance the comparability of results across studies using self-reports of PA. The Compendium coding scheme links a five-digit code that describes physical activities by major headings (e.g., occupation, transportation, etc.) and specific activities within each major heading with its intensity, defined as the ratio of work metabolic rate to a standard resting metabolic rate (MET). Energy expenditure in MET-minutes, MET-hours, kcal, or kcal per kilogram body weight can be estimated for specific activities by type or MET intensity. Additions to the Compendium were obtained from studies describing daily PA patterns of adults and studies measuring the energy cost of specific physical activities in field settings. The updated version includes two new major headings of volunteer and religious activities, extends the number of specific activities from 477 to 605, and provides updated MET intensity levels for selected activities.


Medicine and Science in Sports and Exercise | 1993

Compendium of physical activities: classification of energy costs of human physical activities.

Barbara E. Ainsworth; William L. Haskell; Arthur S. Leon; David R. Jacobs; Henry J. Montoye; James F. Sallis; Ralph S. Paffenbarger

A coding scheme is presented for classifying physical activity by rate of energy expenditure, i.e., by intensity. Energy cost was established by a review of published and unpublished data. This coding scheme employs five digits that classify activity by purpose (i.e., sports, occupation, self-care), the specific type of activity, and its intensity as the ratio of work metabolic rate to resting metabolic rate (METs). Energy expenditure in kilocalories or kilocalories per kilogram body weight can be estimated for all activities, specific activities, or activity types. General use of this coding system would enhance the comparability of results across studies using self reports of physical activity.


The Lancet | 1996

Randomised trial of effect of alendronate on risk of fracture in women with existing vertebral fractures

Dennis M. Black; Steven R. Cummings; David B. Karpf; Jane A. Cauley; Desmond E. Thompson; Michael C. Nevitt; Douglas C. Bauer; Harry K. Genant; William L. Haskell; Robert Marcus; Susan M. Ott; James C. Torner; Sara A. Quandt; Theodore F. Reiss; Kristine E. Ensrud

BACKGROUND Previous studies have shown that alendronate can increase bone mineral density (BMD) and prevent radiographically defined (morphometric) vertebral fractures. The Fracture Intervention Trial aimed to investigate the effect of alendronate on the risk of morphometric as well as clinically evident fractures in postmenopausal women with low bone mass. METHODS Women aged 55-81 with low femoral-neck BMD were enrolled in two study groups based on presence or absence of an existing vertebral fracture. Results for women with at least one vertebral fracture at baseline are reported here. 2027 women were randomly assigned placebo (1005) or alendronate (1022) and followed up for 36 months. The dose of alendronate (initially 5 mg daily) was increased (to 10 mg daily) at 24 months, with maintenance of the double blind. Lateral spine radiography was done at baseline and at 24 and 36 months. New vertebral fractures, the primary endpoint, were defined by morphometry as a decrease of 20% (and at least 4 mm) in at least one vertebral height between the baseline and latest follow-up radiograph. Non-spine clinical fractures were confirmed by radiographic reports. New symptomatic vertebral fractures were based on self-report and confirmed by radiography. FINDINGS Follow-up radiographs were obtained for 1946 women (98% of surviving participants). 78 (8.0%) of women in the alendronate group had one or more new morphometric vertebral fractures compared with 145 (15.0%) in the placebo group (relative risk 0.53 [95% Cl 0.41-0.68]). For clinically apparent vertebral fractures, the corresponding numbers were 23 (2.3%) alendronate and 50 (5.0%) placebo (relative hazard 0.45 [0.27-0.72]). The risk of any clinical fracture, the main secondary endpoint, was lower in the alendronate than in the placebo group (139 [13.6%] vs 183 [18.2%]; relative hazard 0.72 [0.58-0.90]). The relative hazards for hip fracture and wrist fracture for alendronate versus placebo were 0.49 (0.23-0.99) and 0.52 (0.31-0.87). There was no significant difference between the groups in numbers of adverse experiences, including upper-gastrointestinal disorders. INTERPRETATION We conclude that among women with low bone mass and existing vertebral fractures, alendronate is well tolerated and substantially reduces the frequency of morphometric and clinical vertebral fractures, as well as other clinical fractures.


Circulation | 2007

Physical activity and public health: updated recommendation for adults from the American College of Sports Medicine and the American Heart Association.

William L. Haskell; I-Min Lee; Russell R. Pate; Kenneth E. Powell; Steven N. Blair; Barry A. Franklin; Caroline A. Macera; Gregory W. Heath; Paul D. Thompson; Adrian Bauman

On Line Network is a listserv that creates an international network of physical activity and public health practitioners, researchers, and interested others. To subscribe to this listserv, send an email to [email protected]. In the body of the email type: SUBSCRIBE PHYS-ACT, along with your first and last name or anonymous, if you wish to have your subscription hidden. from the Centers for Disease Control and Prevention. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the Centers for Disease Control and Prevention. The University of South Carolina does not discriminate in educational or employment opportunities or decisions for qualified persons on the basis of race Promoting Health Through Physical Activity partners and stakeholders in center activities, and increase participation in cancer prevention and control behaviors among high-risk and disparate populations. Physical Activity Resources We maintain an extensive website (http:// prevention.sph.sc.edu/index.htm) to provide resources and information to researchers, public health practitioners, and others who are interested in promoting physical activity in their communities. The USC Prevention Research Center Notes is a quarterly e-mail newsletter with current information about physical activity and public health. To subscribe to the newsletter, send an email to [email protected]. In the body of the email type: SUBSCRIBE PRCNEWS, along with your first and last name or anonymous, if you wish to have your subscription hidden. Please visit the USC PRC website to explore our physical activity tools, many developed by the PRC, often in partnership with local communities.SUMMARY In 1995 the American College of Sports Medicine and the Centers for Disease Control and Prevention published national guidelines on Physical Activity and Public Health. The Committee on Exercise and Cardiac Rehabilitation of the American Heart Association endorsed and supported these recommendations. The purpose of the present report is to update and clarify the 1995 recommendations on the types and amounts of physical activity needed by healthy adults to improve and maintain health. Development of this document was by an expert panel of scientists, including physicians, epidemiologists, exercise scientists, and public health specialists. This panel reviewed advances in pertinent physiologic, epidemiologic, and clinical scientific data, including primary research articles and reviews published since the original recommendation was issued in 1995. Issues considered by the panel included new scientific evidence relating physical activity to health, physical activity recommendations by various organizations in the interim, and communications issues. Key points related to updating the physical activity recommendation were outlined and writing groups were formed. A draft manuscript was prepared and circulated for review to the expert panel as well as to outside experts. Comments were integrated into the final recommendation. PRIMARY RECOMMENDATION To promote and maintain health, all healthy adults aged 18 to 65 yr need moderate-intensity aerobic (endurance) physical activity for a minimum of 30 min on five days each week or vigorous-intensity aerobic physical activity for a minimum of 20 min on three days each week. [I (A)] Combinations of moderate- and vigorous-intensity activity can be performed to meet this recommendation. [IIa (B)] For example, a person can meet the recommendation by walking briskly for 30 min twice during the week and then jogging for 20 min on two other days. Moderate-intensity aerobic activity, which is generally equivalent to a brisk walk and noticeably accelerates the heart rate, can be accumulated toward the 30-min minimum by performing bouts each lasting 10 or more minutes. [I (B)] Vigorous-intensity activity is exemplified by jogging, and causes rapid breathing and a substantial increase in heart rate. In addition, every adult should perform activities that maintain or increase muscular strength and endurance a minimum of two days each week. [IIa (A)] Because of the dose-response relation between physical activity and health, persons who wish to further improve their personal fitness, reduce their risk for chronic diseases and disabilities or prevent unhealthy weight gain may benefit by exceeding the minimum recommended amounts of physical activity. [I (A)].


Medicine and Science in Sports and Exercise | 2011

2011 Compendium of Physical Activities: A Second Update of Codes and MET Values

Barbara E. Ainsworth; William L. Haskell; Stephen D. Herrmann; Nathanael Meckes; David R. Bassett; Catrine Tudor-Locke; Jennifer L. Greer; Jesse W. Vezina; Melicia C. Whitt-Glover; Arthur S. Leon

PURPOSE The Compendium of Physical Activities was developed to enhance the comparability of results across studies using self-report physical activity (PA) and is used to quantify the energy cost of a wide variety of PA. We provide the second update of the Compendium, called the 2011 Compendium. METHODS The 2011 Compendium retains the previous coding scheme to identify the major category headings and specific PA by their rate of energy expenditure in MET. Modifications in the 2011 Compendium include cataloging measured MET values and their source references, when available; addition of new codes and specific activities; an update of the Compendium tracking guide that links information in the 1993, 2000, and 2011 compendia versions; and the creation of a Web site to facilitate easy access and downloading of Compendium documents. Measured MET values were obtained from a systematic search of databases using defined key words. RESULTS The 2011 Compendium contains 821 codes for specific activities. Two hundred seventeen new codes were added, 68% (561/821) of which have measured MET values. Approximately half (317/604) of the codes from the 2000 Compendium were modified to improve the definitions and/or to consolidate specific activities and to update estimated MET values where measured values did not exist. Updated MET values accounted for 73% of all code changes. CONCLUSIONS The Compendium is used globally to quantify the energy cost of PA in adults for surveillance activities, research studies, and, in clinical settings, to write PA recommendations and to assess energy expenditure in individuals. The 2011 Compendium is an update of a system for quantifying the energy cost of adult human PA and is a living document that is moving in the direction of being 100% evidence based.


The Lancet | 2012

Global physical activity levels: surveillance progress, pitfalls, and prospects

Pedro Curi Hallal; Lars Bo Andersen; Fiona Bull; Regina Guthold; William L. Haskell; Ulf Ekelund

To implement effective non-communicable disease prevention programmes, policy makers need data for physical activity levels and trends. In this report, we describe physical activity levels worldwide with data for adults (15 years or older) from 122 countries and for adolescents (13-15-years-old) from 105 countries. Worldwide, 31·1% (95% CI 30·9-31·2) of adults are physically inactive, with proportions ranging from 17·0% (16·8-17·2) in southeast Asia to about 43% in the Americas and the eastern Mediterranean. Inactivity rises with age, is higher in women than in men, and is increased in high-income countries. The proportion of 13-15-year-olds doing fewer than 60 min of physical activity of moderate to vigorous intensity per day is 80·3% (80·1-80·5); boys are more active than are girls. Continued improvement in monitoring of physical activity would help to guide development of policies and programmes to increase activity levels and to reduce the burden of non-communicable diseases.


Circulation | 1994

Effects of intensive multiple risk factor reduction on coronary atherosclerosis and clinical cardiac events in men and women with coronary artery disease. The Stanford Coronary Risk Intervention Project (SCRIP).

William L. Haskell; Edwin L. Alderman; Joan M. Fair; David J. Maron; S F Mackey; H R Superko; Paul T. Williams; I M Johnstone; M A Champagne; Ronald M. Krauss

BACKGROUND Recent clinical trials have shown that modification of plasma lipoprotein concentrations can favorably alter progression of coronary atherosclerosis, but no data exist on the effects of a comprehensive program of risk reduction involving both changes in lifestyle and medications. This study tested the hypothesis that intensive multiple risk factor reduction over 4 years would significantly reduce the rate of progression of atherosclerosis in the coronary arteries of men and women compared with subjects randomly assigned to the usual care of their physician. METHODS AND RESULTS Three hundred men (n = 259) and women (n = 41) (mean age, 56 +/- 7.4 years) with angiographically defined coronary atherosclerosis were randomly assigned to usual care (n = 155) or multifactor risk reduction (n = 145). Patients assigned to risk reduction were provided individualized programs involving a low-fat and -cholesterol diet, exercise, weight loss, smoking cessation, and medications to favorably alter lipoprotein profiles. Computer-assisted quantitative coronary arteriography was performed at baseline and after 4 years. The main angiographic outcome was the rate of change in the minimal diameter of diseased segments. All subjects underwent medical and risk factor evaluations at baseline and yearly for 4 years, and reasons for all hospitalizations and deaths were documented. Of the 300 subjects randomized, 274 (91.3%) completed a follow-up arteriogram, and 246 (82%) had comparative measurements of segments with visible disease at baseline and follow-up. Intensive risk reduction resulted in highly significant improvements in various risk factors, including low-density lipoprotein cholesterol and apolipoprotein B (both, 22%), high-density lipoprotein cholesterol (+12%), plasma triglycerides (-20%), body weight (-4%), exercise capacity (+20%), and intake of dietary fat (-24%) and cholesterol (-40%) compared with relatively small changes in the usual-care group. No change was observed in lipoprotein(a) in either group. The risk-reduction group showed a rate of narrowing of diseased coronary artery segments that was 47% less than that for subjects in the usual-care group (change in minimal diameter, -0.024 +/- 0.066 mm/y versus -0.045 +/- 0.073 mm/y; P < .02, two-tailed). Three deaths occurred in each group. There were 25 hospitalizations in the risk-reduction group initiated by clinical cardiac events compared with 44 in the usual-care group (rate ratio, 0.61; P = .05; 95% confidence interval, 0.4 to 0.9). CONCLUSIONS Intensive multifactor risk reduction conducted over 4 years favorably altered the rate of luminal narrowing in coronary arteries of men and women with coronary artery disease and decreased hospitalizations for clinical cardiac events.


Medicine and Science in Sports and Exercise | 2001

CHAMPS Physical Activity Questionnaire for Older Adults: outcomes for interventions.

Anita L. Stewart; Kristin M. Mills; Abby C. King; William L. Haskell; Dawn Gillis; Philip L. Ritter

PURPOSE To evaluate effectively interventions to increase physical activity among older persons, reliable and valid measures of physical activity are required that can also detect the expected types of physical activity changes in this population. This paper describes a self-report physical activity questionnaire for older men and women, developed to evaluate the outcomes of the Community Healthy Activities Model Program for Seniors (CHAMPS), an intervention to increase physical activity. METHODS The questionnaire assesses weekly frequency and duration of various physical activities typically undertaken by older adults. We estimated caloric expenditure/wk expended in physical activity and created a summary frequency/wk measure. We calculated measures of each of these for: 1) activities of at least moderate intensity (MET value >/= 3.0); and 2) all specified physical activities, including those of light intensity. Six-month stability was estimated on participants not likely to change (assessment-only control group, physically active cohort). Several tests of construct validity were conducted, and sensitivity to change was analyzed based on response to the CHAMPS intervention. RESULTS The sample (N = 249) comprised underactive persons (N = 173 from the CHAMPS trial) and active persons (N = 76). The sample was aged 65-90 yr (mean = 74, SD = 6); 64% were women, and 9% were minorities. Six-month stability ranged from 0.58 to 0.67, using intraclass correlation coefficients. Nearly all construct validity hypotheses were confirmed, though correlations were modest. All measures were sensitive to change (P < or = 0.01), with small to moderate effect sizes (0.38-0.64). CONCLUSIONS The CHAMPS measure may be useful for evaluating the effectiveness of programs aimed at increasing levels of physical activity in older adults.


Circulation | 2007

Resistance Exercise in Individuals With and Without Cardiovascular Disease: 2007 Update A Scientific Statement From the American Heart Association Council on Clinical Cardiology and Council on Nutrition, Physical Activity, and Metabolism

Mark A. Williams; William L. Haskell; Philip A. Ades; Ezra A. Amsterdam; Vera Bittner; Barry A. Franklin; Meg Gulanick; Susan T. Laing; Kerry J. Stewart

Prescribed and supervised resistance training (RT) enhances muscular strength and endurance, functional capacity and independence, and quality of life while reducing disability in persons with and without cardiovascular disease. These benefits have made RT an accepted component of programs for health and fitness. The American Heart Association recommendations describing the rationale for participation in and considerations for prescribing RT were published in 2000. This update provides current information regarding the (1) health benefits of RT, (2) impact of RT on the cardiovascular system structure and function, (3) role of RT in modifying cardiovascular disease risk factors, (4) benefits in selected populations, (5) process of medical evaluation for participation in RT, and (6) prescriptive methods. The purpose of this update is to provide clinicians with recommendations to facilitate the use of this valuable modality.

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Steven N. Blair

University of South Carolina

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Carolyn E. Barlow

University of Texas Southwestern Medical Center

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Paul T. Williams

Lawrence Berkeley National Laboratory

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