Maintaining Muscle Mass in Older Adults

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1 Maintaining Muscle Mass in Older Adults Nutrition and Exercise Strategies Douglas Paddon-Jones, Ph.D. Professor, Nutrition and Metabolism The University of Texas Medical Branch

2 Disclosures Dr. Paddon-Jones is a Research Investigator with funding from the National Institute of Health (NIH), the Dairy Research Institute and the National Space Biomedical Research Institute (NSBRI). Dr. Paddon-Jones is a member of the Scientific Advisory Board or Speaker s Bureau for the National Dairy Council, US Dairy Export Council, American Egg Board, Texas Beef Council and Abbott Nutrition.

3. protein distribution and daily requirements

3 Overview 1. building muscle in response to protein: young vs. elderly 2. how much protein do older adults need and when? 3. protein distribution and daily requirements 4. priority areas: what happens if you are injured or sick? 5. sarcopenia and a new approach to interventions

4 Maintaining Muscle Mass and Function Synthesis Balance Breakdown Muscle growth Malnutrition Inactivity Illness/Injury Hormones Exercise Nutrition Protein Muscle loss

5 Stable Isotope Methodology (ring - 13 C 6 - Phenylalanine) Artery Synthesis Breakdown Vein

6 1. Building muscle in response to protein

Protein Synthesis (%/h) Stimulating Muscle Growth with Protein 0.14 0.12 * * 0.1 0.08 0.

7 Protein Synthesis (%/h) Stimulating Muscle Growth with Protein * * % increase Young Elderly 0 Fasting 30 g protein Symons et. al. AJCN, 2007

8 2. How much protein do we need and when?

9 Protein Synthesis (%/h) How much protein do we need? - a message of moderation - 30 g protein 90 g protein * * * * Fasting 30 g protein Fasting 90 g protein Young Old ~1.2 g/kg/day for 75kg individual Symons et. al. AJCN, 2007 Symons et. al. JADA. 2009

Protein Synthesis (%/h) Key points 0.18 0.

02 No age-related impairment * * 0 Symons

10 Protein Synthesis (%/h) Key points No age-related impairment * * 0 Symons et. al. AJCN, 2007 Fasting Moderate protein meal

11 Net Muscle Protein Synthesis (mg Phe/leg) Age-related dose-response 60 6 g 50 Young Elderly 5 g 8 g 0 More than ~25 g protein Less than ~15 g protein 6 g Katsanos et. al. AJCN, 2005

12 Protein + Exercise +

Protein Synthesis (%/h) Additive Effect of Protein and Exercise 0.18 0.16 * * 0.14 0.12 100% increase * * 0.1 0.

13 Protein Synthesis (%/h) Additive Effect of Protein and Exercise * * % increase * * % increase Young Elderly 0 Fasting Protein meal Protein + Exercise Symons et. al. JNHA, 2010

14 3. Protein distribution and recommendations

15 How Much Protein Do We Eat? Protein consumed in Australia (grams per day) HIGH PROTEIN DIETS Males 5 th % 50 th % 95 th % 19-30y y y y Females good thing I moved 19-30y y y y Source : NNS 95 (M. Noakes)

16 Daily protein distribution - typical? - maximum rate of protein synthesis Catabolism Anabolism 10 g 15 g 65 g Total Protein 90 g ~ 1.3 g/kg/day A skewed daily protein distribution fails to maximize potential for muscle growth Paddon-Jones and Rasmussen 2009

17 Daily protein distribution - typical? - maximum rate of protein synthesis Catabolism Anabolism 10 g X 15 g 65 g 30 g Total Protein 90 g Usable Protein 55 g A skewed daily protein distribution fails to maximize potential for muscle growth ~ 0.7 g/kg/day Paddon-Jones and Rasmussen 2009

Daily protein distribution - Optimal - maximum

3 g/kg/day Repeated maximal stimulation of

18 Daily protein distribution - Optimal - maximum rate of protein synthesis Catabolism Anabolism 30 g 30g 30 g Total Protein 90 g Usable Protein 90 g ~ 1.3 g/kg/day Repeated maximal stimulation of protein synthesis increase / maintenance of muscle mass Paddon-Jones and Rasmussen 2009

19 Exercise/Rehabilitation and Protein Distribution Effective exercise? maximum rate of protein synthesis Catabolism Anabolism 10 g 15 g 65 g Total Protein 90 g

20 Exercise/Rehabilitation and Protein Distribution Effective exercise maximum rate of protein synthesis Catabolism Anabolism 30 g 30g 30 g Total Protein 90 g

21 4. priority areas: dealing with injury or illness

22 Bed rest is a defacto treatment modality - if you re hospitalized you become inactive - % of Time Inactive (0 steps/min) Low Activity (< 15 steps/min)

23 Loss of lean leg mass (g) Inactivity and Aging Muscle Healthy Young 28 Days Inactivity Healthy Elders 10 Days Inactivity % total lean leg mass 3 times more muscle loss 1/3 the time All volunteers consumed the RDA for protein % total lean leg mass Paddon-Jones et. al Kortebein et al. 2007

Protein Synthesis (%/h) Inactivity reduces muscle protein synthesis 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.

24 Protein Synthesis (%/h) Inactivity reduces muscle protein synthesis Day 1 Day 10 * 30% 24 h muscle protein synthesis during 10 day of inactivity in elders (stable isotope methodology) Kortebein et al. 2007

25 Protein Synthesis (%/h) Protein combats muscle loss during inactivity Day 1 Day 10 - older adults - # * 30% Normal Diet Normal Diet + Amino Acids Normal Diet Normal Diet + Amino Acids Ferrando & Paddon-Jones et. al. 2009

26 Loss of lean leg mass (g) Muscle Loss in Hospitalized Older Adults Healthy Young 28 Days Inactivity Healthy Elders 10 Days Inactivity Elderly Inpatients 3 days hospitalization % total lean leg mass 10% total lean leg mass 10+ % total lean leg mass Paddon-Jones, Pilot Data

27 5. Sarcopenia and a new approach to interventions

(kg) (kg) Sarcopenia: - definitions - 55 Lean Body Mass 35 Fat Mass 50 45 40 35 30 20 30 40 50 60 70 80 30 25 20 15 10 5 20 30 40 50 60 70 80 Age (years) Age (years) a syndrome

28 (kg) (kg) Sarcopenia: - definitions - 55 Lean Body Mass 35 Fat Mass Age (years) Age (years) a syndrome characterized by progressive and generalized loss of skeletal muscle mass and strength with a risk of adverse outcomes such as physical disability and poor quality of life. Holloszy, Mayo Clin Proc. 2000

29 Lean muscle mass (kg) Alternate model of muscle loss - developing tactical nutrition interventions Age (yrs)

30 Prevention and treatment strategies PREVENTION: Adopt a meal-based approach to protein consumption Consume a moderate amount of high-quality protein, 3-times per day Consume protein in close proximity to exercise

31 Prevention and treatment strategies TREATMENT: React aggressively with nutritional support to reduce the rapid loss of muscle and strength associated with physical inactivity, illness or injury

32 Emily Arentson-Lantz, Ph.D. Fellow Kirk English Doctoral Student Barbara Doucet, OT., Ph.D Assistant Professor Joni Mettler, Ph.D. Assistant Professor, TSU Christopher Danesi Coordinator

Dietary protein: guidelines, requirements and a lack of common sense

Dietary protein: guidelines, requirements and a lack of common sense Douglas Paddon-Jones, Ph.D. The University of Texas Medical Branch Overview 1. protein metabolism 2. building muscle in response to