Nutrition and Exercise Concerns of Middle Age

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Nutrition and Exercise Concerns of

Middle Age

Nutrition and Exercise Concerns of

Middle Age Edited by

Judy A. Driskell

Boca Raton London New York

CRC Press is an imprint of the Taylor & Francis Group, an informa business

CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487‑2742 © 2009 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Printed in the United States of America on acid‑free paper 10 9 8 7 6 5 4 3 2 1 International Standard Book Number‑13: 978‑1‑4200‑6601‑2 (Hardcover) This book contains information obtained from authentic and highly regarded sources. Reasonable efforts have been made to publish reliable data and information, but the author and publisher can‑ not assume responsibility for the validity of all materials or the consequences of their use. The authors and publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint. Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www.copy‑ right.com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978‑750‑8400. CCC is a not‑for‑profit organization that pro‑ vides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Library of Congress Cataloging‑in‑Publication Data Nutrition and exercise concerns of middle age / editor, Judy A. Driskell. p. cm. Includes bibliographical references and index. ISBN 978‑1‑4200‑6601‑2 (alk. paper) 1. Middle‑aged persons‑‑Nutrition. 2. Exercise for middle‑aged persons. I. Driskell, Judy A. (Judy Anne) TX361.M47N88 2008 613.2’0844‑‑dc22 Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com

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This book is dedicated to the experts who wrote the included chapters.

Contents Preface.......................................................................................................................xi The Editor............................................................................................................... xiii Contributors.............................................................................................................. xv

Section Iâ•… Introduction Chapter 1 Introduction: Nutrition and Exercise Concerns of Middle Age............3 Judy A. Driskell

Section II╅ Energy-Yielding Nutrients Chapter 2 Carbohydrates.....................................................................................25 Michael S. Green and J. Andrew Doyle Chapter 3 Lipids................................................................................................... 53 Sarah J. Ehlers, Heather E.€Rasmussen, and Ji-Young Lee Chapter 4 Proteins................................................................................................ 87 Brian S. Snyder and Mark D. Haub

Section III╅ Vitamins Chapter 5 Fat-Soluble Vitamins......................................................................... 111 Maria Stacewicz-Sapuntzakis and Gayatri Borthakur Chapter 6 Vitamin C.......................................................................................... 149 Herb E. Schellhorn and Yi Li Chapter 7 B-Vitamins........................................................................................ 169 George U. Liepa, Sandra D. Pernecky, Steven€J.€Pernecky, and Stephen J. McGregor vii

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Contents

Section IVâ•… Minerals Chapter 8 Major Minerals—Calcium, Magnesium, and Phosphorus............... 193 Forrest H. Nielsen Chapter 9 Iron.................................................................................................... 219 Emily M. Haymes Chapter 10 Trace Elements Excluding Iron—Chromium and Zinc.................... 233 Henry C. Lukaski and Angus G. Scrimgeour

Section Vâ•… Fluids and Hydration Chapter 11 Fluids, Electrolytes, and Hydration................................................... 253 Douglas S. Kalman

Section VIâ•… Other Commonly Consumed Substances Chapter 12 Caffeine and Tannins........................................................................ 269 Jay Kandiah and Valerie A. Amend Chapter 13 Herbal Supplements.......................................................................... 283 Jidong Sun and David W. Giraud

Section VII╅ Recreational Activities Chapter 14 Endurance Training........................................................................... 317 Shawn R. Simonson and Catherine€G. Ratzin-Jackson Chapter 15 Resistance Training........................................................................... 353 Robert J. Moffatt, Jacob M.€Wilson, and Tait Lawrence

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Contents

Section VIIIâ•… Age-Related Disorders Chapter 16 Cardiovascular Issues........................................................................ 397 Susan Hazels Mitmesser Chapter 17 Cancer............................................................................................... 415 Farid E. Ahmed Appendices............................................................................................................. 457 Index....................................................................................................................... 485

Preface The scientific and lay media extol the health benefits of good nutrition and physical activity. Most books that have been published about nutrition and physical activity have dealt with nutritional needs of young adults who exercise vigorously. At around 30 years of age or so, individuals start to become more concerned about having and maintaining good health and realizing the personal benefits of good nutrition and moderate-intensity physical activity. Some health professionals seem to believe that nutrition and physical activity information is the same for all people. What constitutes good nutrition and exercise habits is generally not interpreted for middle-aged individuals. Middle age is considered to be around 30 to 60 years of age. Middleaged individuals most often are not involved in collegiate or professional sports but frequently do exercise on a regular basis as a form of recreation. Middle-aged adults are concerned about obtaining and maintaining good health and how they can reduce their risk of chronic diseases. This volume includes a collection of chapters written by scientists from several academic disciplines who have expertise in an area of nutrition or kinesiology as it relates to exercise and sport. The introductory chapter on nutrition and exercise concerns of middle age is followed by chapters on the energy-yielding nutrients (carbohydrates, lipids, and proteins), three chapters on the vitamins (fat-soluble vitamins, vitamin C, and B-vitamins), three chapters on the minerals (major minerals, iron, and trace elements excluding iron). A chapter is included on fluids, electrolytes, and hydration. Chapters are included on the commonly consumed substances caffeine and tannins as well as herbal supplements. Two chapters describe resistance training and endurance training relating these to nutrient intakes, exercise recommendations, and overall health. The age-related chronic diseases cardiovascular disorders and cancer are discussed in relation to nutrition and exercise. The book also includes appendices that list nutrient recommendations for middle-aged adults established by three major organizations: the Institute of Medicine, National Academy of Sciences for those living in the United States and Canada; the National Health and Medical Council (Australia and New Zealand Government for those living in Australia and New Zealand); and the World Health Organization. The daily values for vitamins and minerals are also listed. Sports nutritionists, sports medicine and fitness professionals, researchers, coaches, trainers, physicians, dietitians, nurses, athletes, students, and the wellinformed layperson will find this book to be informative and timely. It discusses “cutting edge” research on the topics of nutrition and exercise. Judy A. Driskell, Ph.D., R.D. Professor, University of Nebraska

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The Editor Judy Anne Driskell, Ph.D., R.D. is Professor of Nutritional Science and Dietetics at the University of Nebraska. She received her B.S. degree in Biology from the University of Southern Mississippi in Hattiesburg. Her M.S. and Ph.D. degrees were obtained from Purdue University. She has served in research and teaching positions at Auburn University, Florida State University, Virginia Polytechnic Institute and State University, and the University of Nebraska. She has also served as the Nutrition Scientist for the U.S. Department of Agriculture/Cooperative State Research Service and as a Professor of Nutrition and Food Science at Gadjah Mada and Bogor Universities in Indonesia. Dr. Driskell is a member of numerous professional organizations including the American Society of Nutritional Sciences, the American College of Sports Medicine, the International Society of Sports Nutrition, the Institute of Food Technologists, and the American Dietetic Association. In 1993 she received the Professional Scientist Award of the Food Science and Human Nutrition Section of the Southern Association of Agricultural Scientists. In addition, she was the 1987 recipient of the Borden Award for Research in Applied Fundamental Knowledge of Human Nutrition. She is listed as an expert in B-Complex Vitamins by the Vitamin Nutrition Information Service. Dr. Driskell co-edited the CRC book Sports Nutrition: Minerals and Electrolytes with Constance V. Kies. In addition, she authored the textbook Sports Nutrition and co-authored the advanced nutrition book Nutrition: Chemistry and Biology, both published by CRC. She co-edited Sports Nutrition: Vitamins and Trace Elements, first and second editions; Macroelements, Water, and Electrolytes in Sports Nutrition; Energy-Yielding Macronutrients and Energy Metabolism in Sports Nutrition; Nutritional Applications in Exercise and Sport; Nutritional Assessment of Athletes; Nutritional Ergogenic Aids; and Sports Nutrition: Energy Metabolism and Exercise; all with Ira Wolinsky. She also edited the book Sports Nutrition: Fats and Proteins, published by CRC Press. She has published more than 160 refereed research articles and 16 book chapters as well as several publications intended for lay audiences and has given numerous presentations to professional and lay groups. Her current research interests center around vitamin metabolism and requirements, including the interrelationships between exercise and water-soluble vitamin requirements.

xiii

Contributors Farid E. Ahmed, Ph.D. GEM Tox Consultants and Labs, Inc. Greenville, North Carolina Valerie A. Amend, B.S. Department of Family and Consumer Sciences Ball State University Muncie, Indiana Gayatri Borthakur, Ph.D. Department of Kinesiology and Nutrition University of Illinois at Chicago Chicago, Illinois J. Andrew Doyle, Ph.D. Department of Kinesiology and Health Georgia State University Atlanta, Georgia

Michael S. Green, Ph.D. Department of Kinesiology and Health Promotion Troy University Troy, Alabama Mark D. Haub, Ph.D. Department of Human Nutrition Kansas State University Manhattan, Kansas Emily M. Haymes, Ph.D. Department of Nutrition, Food and Exercise Sciences Florida State University Tallahassee, Florida

Judy A. Driskell, Ph.D., R.D. Department of Nutrition and Health Sciences University of Nebraska Lincoln, Nebraska

Douglas S. Kalman, Ph.D., R.D., C.C.R.C., F.A.C.N. Nutrition and Applied Clinical Research Miami Research Associates South Miami, Florida and Department of Dietetics and Nutrition Florida International University

Sarah J. Ehlers, M.S. Department of Nutrition and Health Sciences University of Nebraska Lincoln, Nebraska

Jay Kandiah, Ph.D. Department of Family and Consumer Sciences Ball State University Muncie, Indiana

David W. Giraud, M.S. Department of Nutrition and Health Sciences University of Nebraska Lincoln, Nebraska

Tait Lawrence, M.S., C.S.C.S. Department of Nutrition, Food and Exercise Sciences Florida State University Tallahassee, Florida

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xvi

Contributors

Ji-Young Lee, Ph.D. Department of Nutrition and Health Sciences University of Nebraska Lincoln, Nebraska

Sandra D. Pernecky, M.S., R.D. Department of Dietetics and Human Nutrition Eastern Michigan University Ypsilanti, Michigan

Yi Li, M.S. Department of Biology McMaster University Hamilton, Ontario, Canada

Steven J. Pernecky, Ph.D. Department of Chemistry Eastern Michigan University Ypsilanti, Michigan

George U. Liepa, Ph.D., F.A.C.N. School of Health Sciences Eastern Michigan University Ypsilanti, Michigan Henry C. Lukaski, Ph.D. Grand Forks Human Nutrition Research Center U.S. Department of Agriculture, Agricultural Research Service Grand Forks, North Dakota

Heather E. Rasmussen, Ph.D., R.D. Department of Nutrition and Health Sciences University of Nebraska Lincoln, Nebraska Catherine G. Ratzin-Jackson, Ph.D. Department of Kinesiology Fresno State University Fresno, California

Stephen J. McGregor, Ph.D. School of Health Promotion and Human Performance Eastern Michigan University Ypsilanti, Michigan

Herb E. Schellhorn, Ph.D. Department of Biology McMaster University Hamilton, Ontario, Canada

Susan Hazels Mitmesser, Ph.D. Mead Johnson Nutrition Evansville, Indiana

Angus G. Scrimgeour, Ph.D. Military Nutrition Division U.S. Army Research Institute for Environmental Medicine Natick, Massachusetts

Robert J. Moffatt, Ph.D., M.P.H. Department of Nutrition, Food and Exercise Sciences Florida State University Tallahassee, Florida Forrest H. Nielsen, Ph.D. Grand Forks Human Nutrition Research Center U.S. Department of Agriculture, Agricultural Research Center Grand Forks, North Dakota

Shawn R. Simonson, Ed.D., C.S.C.S., A.C.S.M., H.F.S. Department of Kinesiology Boise State University Boise, Idaho Brian S. Snyder, M.S. Department of Human Nutrition Kansas State University Manhattan, Kansas

xvii

Contributors

Maria Stacewicz-Sapuntzakis, Ph.D. Department of Kinesiology and Nutrition University of Illinois at Chicago Chicago, Illinois Jidong Sun, Ph.D. Perrigo Company Holland, Michigan

Jacob M. Wilson, M.S., C.S.C.S. Department of Nutrition, Food and Exercise Sciences Florida State University Tallahassee, Florida

Section I Introduction

1 Nutrition and Exercise Introduction:

Concerns of Middle Age Judy A. Driskell Contents I. Introduction.......................................................................................................3 II. Definition of Middle Age...................................................................................5 III. Energy Balance..................................................................................................6 IV. Nutrient Recommendations...............................................................................8 V. Dietary Guidelines........................................................................................... 13 VI. Food Guidance Recommendations.................................................................. 16 VII. Exercise Recommendations............................................................................. 16 VIII. Conclusions......................................................................................................20 References.................................................................................................................20

I.â•… Introduction Middle-aged adults should have good nutritional and exercise habits. These habits influence their physical performance as well as their overall health. The American College of Sports Medicine, American Dietetic Association, and Dietitians of Canada issued a joint position statement on nutrition and athletic performance in 2000.1–3 The key points of this joint position statement are given in Table€1.1. These key points summarize the current energy, nutrient, and fluid recommendations for physically active adults and competitive athletes. These recommendations would also apply to physically active middle-aged adults. This position statement is intended to provide guidance to health professionals working with physically active adults and is not intended for use with children or adolescents. It is currently being updated. The updated version, once it is available, can be accessed via the websites of these organizations. According to the World Health Organization (WHO), about 30% of deaths in the world in 1999 were due to cardiovascular diseases, and this percentage is expected to increase.4 One of the main objectives of the WHO’s global strategy for the prevention and control of noncommunicable diseases is to reduce exposure in an integrated manner to the major risk factors of tobacco use, unhealthy diet, and physical inactivity. Unhealthy diets and physical inactivity are a problem to populations worldwide.

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4

Nutrition and Exercise Concerns of Middle Age

TABLE€1.1 Key Points of the Joint Position Statement of the American College of Sports Medicine, American Dietetic Association, and Dietitians of Canada on Nutrition and Athletic Performance • During times of high-intensity training, adequate energy needs to be consumed to maintain body weight, maximize the training effects, and maintain health. Low-energy intakes can result in loss of muscle mass, menstrual dysfunction, loss or failure to gain body density, and increased risk of fatigue, injury, and illness. • Body weight and composition can affect exercise performance but should not be used as the sole criterion for participation in sports; daily weigh-ins are discouraged. Optimal body-fat levels vary depending upon the sex, age, and heredity of the athlete, as well as the sport itself. Body-fat assessment techniques have inherent variability, thus limiting the precision with which they can be interpreted. If weight loss (fat loss) is desired, it should start early—before the competitive season—and involve a trained health and nutrition professional. • Protein requirements are slightly increased in highly active people. Protein recommendations for endurance athletes are 1.2 to 1.4 g/kg body weight per day, whereas those for resistance and strength-trained athletes may be as high as 1.6 to 1.7 g/kg body weight per day. These recommended protein intakes can generally be met through diet alone, without the use of protein or amino acid supplements, if energy intake is adequate to maintain body weight. • Fat intake should not be resisted, because there is no performance benefit in consuming a diet with less than 15% of energy from fat, compared with 20% to 25% of energy from fat. Fat is important in the diets of athletes as it provides energy, fat-soluble vitamins, and essential fatty acids. Additionally, there is no scientific basis on which to recommend high-fat diets to athletes. • The athletes at greatest risk of micronutrient deficiencies are those who restrict energy intake or use severe weight-loss practices, eliminate one or more food groups from their diet, or consume high-carbohydrate diets with low micronutrient density. Athletes should strive to consume diets that provide at least the RDAs/DRIs for all micronutrients from food. • Dehydration decreases exercise performance; thus, adequate fluid before, during, and after exercise is necessary for health and optimal performance. Athletes should drink enough fluid to balance their fluid losses. Two hours before exercise 400 to 600 mL (14 to 22 oz) of fluid should be consumed, and during exercise 150 to 350 mL (5 to 12 oz) of fluid should be consumed every 15 to 20 minutes depending on tolerance. After exercise the athlete should drink adequate fluids to replace sweat losses during exercise. The athlete needs to drink at least 450 to 675 mL (16 to 24 oz) of fluid for every pound (0.5 kg) of body weight lost during exercise. • Before exercise, a meal or snack should provide sufficient fluid to maintain hydration, be relatively low in fat and fiber to facilitate gastric emptying and minimize gastrointestinal distress, be relatively high in carbohydrate to maximize maintenance of blood glucose, be moderate in protein, and be composed of foods familiar and well tolerated by the athlete. • During exercise, the primary goals for nutrient consumption are to replace fluid losses and provide carbohydrate (approximately 30 to 60 g per hour) for the maintenance of blood glucose levels. These nutrition guidelines are especially important for endurance events lasting longer than an hour, when the athlete has not consumed adequate food or fluid before exercise, or if the athlete is exercising in an extreme environment (heat, cold, or altitude).

Introduction:

5

• After exercise, the dietary goal is to provide adequate energy and carbohydrates to replace muscle glycogen and to ensure rapid recovery. If an athlete is glycogen-depleted after exercise, a carbohydrate intake of 1.5 g/kg body weight during the first 30 minutes and again every 2 hours for 4 to 6 hours will be adequate to replace glycogen stores. Protein consumed after exercise will provide amino acids for the building and repair of muscle tissue. Therefore, athletes should consume a mixed meal providing carbohydrates, protein, and fat soon after a strenuous competition or training session. • In general, no vitamin and mineral supplements should be required if an athlete is consuming adequate energy from a variety of foods to maintain body weight. Supplementation recommendations unrelated to exercise—such as folic acid in women of childbearing potential— should be followed. If an athlete is dieting, eliminating foods or food groups, is sick or recovering from injury, or has a specific micronutrient deficiency, a multivitamin/mineral supplement may be appropriate. No single nutrient supplements should be used without a specific medical or nutritional reason (e.g., iron supplements to reverse iron deficiency anemia). • Athletes should be counseled regarding the use of ergogenic aids, which should be used with caution and only after careful evaluation of the product for safety, efficacy, potency, and legality. • Vegetarian athletes may be at risk for low-energy, -protein, and micronutrient intakes because of high intakes of low-energy-dense foods and the elimination of meat and dairy from the diet. Consultation with a registered dietitian will help to avoid these nutrition problems. Sources: American College of Sports Medicine, Joint position statement: nutrition and athletic performance, Med. Sci. Sports Exerc. 32, 2130–45, 2000.1 Used with the permission of Wolters Kluwer Health. RDAs = Recommended Dietary Allowances; DRIs = Dietary Reference Intakes.

II.â•…Definition of Middle Age Exactly what is middle age? Simply stated, middle age is the period of life between young adulthood and old age. The idea that midlife or middle age is a separate and distinct life stage is a cultural conception that originated in the 20th century.5 The emergence of middle age as a life stage is linked to the increase in longevity and the decrease in fertility.6 Little research has been conducted on the middle aged, especially with regard to nutrition and exercise. Middle age is better defined by a pattern of characteristics as opposed to chronological age. Generally by middle age, adults are expected to have established a family of their own, have found a clear career direction, and have taken on responsibility with respect to their children, their aging parents, and sometimes their community.7 Many physiological changes occur during aging. Aging is a gradual process. Many of the physiological changes that usually occur in healthy individuals during middle age are given in Table€1.2. Good nutrition and exercise practices can moderate the effects of aging on the body’s physiological functioning. Caloric restriction may slow some of the changes that occur in aging.8 Conclusive evidence indicates that endurance and strength training generally slow some of the age-related changes.8–11 The chapters in this book discuss how good nutrition and exercise practices are beneficial to the health status of individuals, particularly during middle age.

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Nutrition and Exercise Concerns of Middle Age

TABLE€1.2 Major Physiological Changes That Occur in Healthy Individuals during Middle Age Brain weight declines around 10% from age 20 or 30 to age 90; however, intellectual performance tends to be maintained until at least age 80 in individuals who do not have neurologic disease.10 Lung function gradually declines after age 20.10 A decrease in height begins at around age 25 in men and 20 in women.8 Loss of muscle mass begins around age 30.9 The number and size of muscle fibers progressively decrease, beginning when individuals are in their 30s; this results in a decrease in skeletal muscle mass and lean body mass.10 A modest increase in the size of the heart occurs from age 20 to 80.8 Plasma endothelin-1 concentration, which is produced by vascular endothelial cells and has been implicated in regulation of vascular tonus and progression of atherosclerosis, was higher in healthy middle aged women (31–47 years) than in healthy young women (21–28 years).11 Intellectual abilities peak during the 30s and plateau through the 50s and 60s.10 Renal blood flow progressively decreases at age 30 to 40 years to age 80.10 Bone density begins to decrease between ages 40 and 50 in both genders, but most rapidly in women.10 The abilities to taste and smell start to gradually diminish when people are in their 50s.9 Adapted from: Masoro, E.J., Challenges of Biological Aging, Springer, New York, 1999;8 Beers, M.H. and Jones, T.V., Eds., The Merck Manual of Health & Aging, Merck Research Laboratories, Whitehouse Station, NJ, 2005;9 Beers, M.H. and Berkow, R., Eds., The Merck Manual of Geriatrics, 3rd ed., Merck Research Laboratories, Whitehouse Station, NJ, 2006;10 Maeda S. et al., Aerobic exercise training reduces plasma endothelin-1 concentration in older women, J. Appl. Physiol. 96, 336–41, 2003.11

Some researchers, governmental agencies, and others have utilized chronological age in designating the middle years of adulthood. These designations vary from 40 to 65 years,12 35 to 54 years,13 25 to 75 years,14 40 to 60 years,15 and 31 to 50 years.16 No consensus exists regarding the entry and exit points of middle age.

III.â•…Energy Balance Energy balance in individuals depends on their energy intakes as well as their energy outputs. The majority of the population in the United States consumes more food energy than they expend, primarily because they are sedentary. Data from the 2006 National Health Interview Survey indicates that 35% of adults 18 years of age and older in the United States were overweight (but not obese) and 26% were obese.17 Sixty-two percent of adults included in the survey reported not participating in any type of vigorous leisure-time physical activity. This is also true in other developed countries, though in some developing countries, most of the population consumes too little food energy. In the United States, food energy is expressed as calories

Introduction:

7

(properly referred to as kilocalories), while some other countries express food energy as kilojoules; one calorie is equal to 4.186 kilojoules18 or 4.18 kilojoules.19 The three major components of energy expenditure are basal metabolism (though sometimes resting metabolism is utilized), thermic effect of food (previously known as specific dynamic action), and physical activity (also known as thermic effect of exercise and as energy expenditure of physical activity). All three of these components decrease as one ages, with a more rapid decline occurring around 40 years of age in men and 50 years of age in women.20,21 The Institute of Medicine, National Academy of Sciences, uses the term Estimated Energy Requirement (EER) which is the average dietary intake predicted to maintain energy balance in a healthy adult of a certain gender, age, weight, height, and level of physical activity that is consistent with good health.18 The formula for calculating the EER for men 19 years of age and older is given below: EER = 662 – (9.53 x age [y]) + PA x (15.91 x weight [kg] + 539.6 x height [m]) The physical activity coefficient (PA) for men is 1.00 for those who are sedentary; 1.11, for low active; 1.25, for active; and 1.48, for very active. The formula for calculating the EER for women 19 years of age and older is given below:

EER = 354 – (6.91 x age [y]) + PA x (9.36 x weight [kg] + 726 x height [m])

The PA for women is 1.00 for those who are sedentary; 1.12, low active; 1.27, active; and 1.45, very active. Individuals who take 30 minutes of moderately intense activity (such as walking 2 miles in 30 minutes) or an equivalent amount of physical exertion in addition to activities involved in maintaining a sedentary lifestyle have a physical activity level (PAL) of about 1.5 and are classified as low active. PALs of ≥1.0–