KIN 267 FALL 2023 Biological Processes of Aging Muscle and Bone (Influence of Protein Creatine) (students) (4).pptx
Transcript
Biological Processes of Aging Muscle & Bone Potential Influence of Dietary Protein & Creatine Copyright ©2021 John Wiley & Sons, Inc. 1 The Impact of Aging The Marbling Effect Fiber type transitions Type II x Type II a Fiber type transitions with aging Type II x Type II a Type I Sp...
Biological Processes of Aging Muscle & Bone Potential Influence of Dietary Protein & Creatine Copyright ©2021 John Wiley & Sons, Inc. 1 The Impact of Aging The Marbling Effect Fiber type transitions Type II x Type II a Fiber type transitions with aging Type II x Type II a Type I Spinal Cord Fast twitch motor neuron Muscle Slow Twitch Motor neuron ST ST FT Spinal Cord Fast twitch motor neuron Muscle Slow Twitch Motor neuron ST Motor neuron death ST FT Spinal Cord Denervation of muscle fibers Fast twitch motor neuron Muscle Slow Twitch Motor neuron ST Motor neuron death ST FT Spinal Cord Denervation of muscle fibers Fast twitch motor neuron Death of some muscle fibers Muscle Slow Twitch Motor neuron ST Motor neuron death ST FT Spinal Cord Fast twitch motor neuron Denervation of muscle fibers Death of some muscle fibers Re-inervation of other muscle fibers Muscle Slow Twitch Motor neuron ST Motor neuron death ST FT Spinal Cord Fast twitch motor neuron Denervation of muscle fibers Death of some muscle fibers Re-inervation of other muscle fibers Conversion of fiber type Muscle Slow Twitch Motor neuron ST Motor neuron death ST ST FT ST Muscle biopsy from a young person FT ST Muscle biopsy from an old person young plantar flexors young plantar flexors older plantar flexors % Torque of Young Group 100 90 80 70 60 50 40 30 20 10 0 Candow & Chilibeck, 2005. a b b Anabolic Resistance Morton et al. (2018). Defining anabolic resistance: implications for delivery of clinical care nutrition. Curr Opin Crit Care, 24: 124-130. PAGE • Recommended dietary allowance of 0.8 grams per kg of protein per day is what the dietary reference intake suggests. • This is all that’s needed to maintain health even for older adults. ! What we’ve been told I’VE GOT A FEVER AND THE ONLY PRESCRIPTION IS MORE PROTEIN MetaA nalysis Morton et al. (2018). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 52: 376-384. PAGE How much protein should you ingest per day? a. 0.8-1.0 grams/kg b. 1.0-1.2 grams/kg c. 1.6-2.2 grams/kg d. > 2.2 grams/kg Morton et al. (2018). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 52: 376-384. Daily I ntake Range How much protein should you ingest per meal if < 40 years of age? a. 0.25 grams/kg b. 0.10 grams/kg c. 0.40 grams/kg d. 0.80 grams/kg How much protein should you ingest per meal if > 40 years of age? a. 0.25 grams/kg b. 0.10 grams/kg c. 0.40 grams/kg d. 0.80 grams/kg PAGE ? Is Timing Important? PAGE When is the best time to consume protein for muscle growth and recovery? a. Immediately before exercise b. During exercise c. Immediately after exercise d. Doesn’t matter PAGE ! However, Post-Exercise Protein An ideal time to recharge, refuel and recover! PAGE Protein Source • Focus on complete protein food sources (dairy, animal, some plant-based) which contains leucine • Leucine is an essential amino acid • Leucine is the ‘spark’ behind muscle protein synthesis Frequent intakes of dietary protein appear optimal vs. 1-2 large meals Offsets the potential Muscle ‘FULL’ effect Aging adults typically consume inadequate protein at breakfast and lunch Therefore, equal distribution of dietary protein intake throughout the day appears optimal Protein Pacing PAGE ! What we know PAGE Summary Dosage per meal Distribution Source Total Daily Amount < 40 yrs of age: 0.25 g/kg > 40 yrs of age: 0.40 g/kg • 3-5 servings • Example: Breakfast, lunch, supper, post-exercise, presleep • Emphasize complete food foods • Focus on Leucine • 1.1-2.2 grams/kg of body mass/day • For individuals exercising frequently and intensely, 2.2 grams/kg of body mass/day or 1 gram/lbs/day should be considered. • Creatine Nitrogen-containing compound (arginine, glycine, methionine) found in red meat and seafood. Click icon to add Click icon to add 2/3 or 70-90 mmol/kg dry muscle stored in muscle as phosphocreatine (PCr) and 1/3 as free creatine. MAINTAINS ATP LEVELS DURING EXERCISE Creatine Distribution Creatine Supplementation During Resistance Training on Lean Tissue Mass in Older Adults • 22 studies were included • 721 men and women (57-70 yrs) • Randomized to creatine supplementation or placebo • Resistance training 2-3 d/wk for 752 wks Chilibeck et al. (2017). Effect of Creatine Supplementation During Resistance Training on Lean Tissue Mass and Muscular Strength in Older Adults: A meta-analysis. Open Access Journal of Sports Medicine, 8: 213-226. OVERALL RESULTS Creatine & resistance training increased lean mass by 1.41 kg vs. placebo IMPORTANT! • Lean tissue mass is a proxy surrogate and poor indicator of muscle mass as it takes into account water and fibrotic tissue which can account for ~ 15% of total muscle area (Cawthon et al. 2020; Taaffe et al. 2009). • Lean tissue mass does not predict muscle strength (Manini & Clark, 2012) or health outcomes (i.e., mobility, activities of daily living) (Bhasin et al. 2020) OVERALL RESULTS Creatine & resistance training increased muscle mass by 700 g vs. placebo? Creatine Supplementation Combined with Resistance Training on Regional Measures of Muscle Hypertrophy • 6 studies were included (5 used ultrasound, 1 used pQCT) • 282 participants (57-72 yrs) • Sample sizes ranged from 25 to 88 Burke et al. (2023). The Effects of Creatine Supplementation Combined with Resistance Training on Regional Measures of Muscle Hypertrophy: A Systematic Review with MetaAnalysis. Nutrients, 15(9): 2116. LIMB MUSCLE SIZE Muscle sites measured: elbow and knee flexors and extensors, ankle plantar- & dorsiflexors Efficacy of Creatine Supplementation and Resistance Training on Area and Density of Bone and Muscle in Older Adults • 53 participants (> 50 yrs of age) • 1 year of supervised resistance training (3 days/week) • Creatine or Placebo: 0.1g/kg/day Candow et al. (2021). Efficacy of creatine supplementation and supervised resistance training on area and density of bone and muscle in older adults. Medicine and Science in Sports and Exercise, 1; 53(11): 2388-2395. peripheral Quantitative Computed Tomography (pQCT) Cr group experienced a significant increase in lower-leg muscle density (Δ + 0.83 ± 1.15 mg·cm3) compared to placebo (Δ − 0.16 ± 1.56 g·cm3) STRENGTH Creatine Supplementation During Resistance Training on Muscular Strength in Older Adults • 22 studies were included • 721 men and women (57-70 yrs) • Randomized to creatine supplementation or placebo • Resistance training 2-3 /wk for 7-52 wks Chilibeck et al. (2017). Effect of Creatine Supplementation during Resistance Training on Lean Tissue Mass and Muscular Strength in Older Adults: A meta-analysis. Open Access Journal of Sports Medicine, 8: 213-226. UPPER BODY STRENGTH LOWER BODY STRENGTH CLINICALLY SIGNIFICANT Lower-body muscle groups are more negatively affected with aging vs. upper-body muscle groups (Candow & Chilibeck, 2005) FUNCTIONALIT Y HOW IT WORKS ● Increases muscle anabolic processes (satellite cells, myogenic transcription factors, IGF1; mTOR kinases, PCr, glycogen and calcium kinetics) ● Decreases muscle catabolic processes (protein breakdown, inflammation, oxidative stress) Chilibeck et al. (2017). Effect of creatine supplementation during resistance training on lean tissue mass and muscular strength in older adults: a metaanalysis. Open Access Journal of Sports Medicine, 8: 213-226. MUSCLE SUMMARY The combination of creatine supplementation and resistance training increases: 1 5 Whole-body lean tissue mass ( ̴ 1.4 kg) Functional ability 2 3 Regional (limb) muscle size Lower-limb muscle density 4 Upper- and lower-body strength BONE Bone • Bone is an organ made up of several different tissues (bone, cartilage, dense connective tissue, adipose, and nervous tissue) working together • The entire framework of bones and their cartilages constitute the skeletal system Copyright ©2021 John Wiley & Sons, Inc. 62 Functions of the Skeletal System 1. Provides support 2. Protects the internal organs (brain, heart, etc.) 3. Assists body movements (in conjunction with muscles) 4. Mineral homeostasis - stores and releases calcium and phosphorus 5. Participates in blood cell production (hemopoiesis) 6. Stores triglycerides Copyright ©2021 John inWiley adipose & Sons, Inc. cells of 63 Histology of Bone Copyright ©2021 John Wiley & Sons, Inc. 64 Histology of Bone (1 of 7) Bone contains an abundant extracellular matrix that surrounds widely separated cells • The extracellular matrix is about 15% water, 30% collagen, and 55% crystalized mineral salts • Mineral salts calcium phosphate and calcium hydroxide combine to form crystals called hydroxyapatite Copyright ©2021 John Wiley & Sons, Inc. 65 Histology of Bone (2 of 7) Bone contains 4 types of cells: • Osteoprogenitor cells (bone stem cells able to differentiate into the other types of cells) • Osteoblasts (bone-building cells that secrete matrix; initiate calcification) • Osteocytes (mature bone cells) • Osteoclasts (remodel bones and cause them to release calcium; bone resorption) Copyright ©2021 John Wiley & Sons, Inc. 66 Histology of Bone Copyright ©2021 John Wiley & Sons, Inc. 67 THE BONE REMODELING PROCESS Histology of Bone • Compact bone is good at providing protection and support; strongest • Spongy bone is lightweight and provides tissue support; also called trabecular or cancellous bone Copyright ©2021 John Wiley & Sons, Inc. 69 Bone’s Role in Calcium Homeostasis Copyright ©2021 John Wiley & Sons, Inc. 70 Bone’s Role in Calcium Homeostasis Bones store 99% of the body’s calcium. The parathyroid gland secretes parathyroid hormone (PTH) when calcium levels drop. Osteoclasts are stimulated to increase bone resorption and calcium is released. PTH also stimulates the production of calcitriol by the kidneys to increase calcium absorption in the intestines. Copyright ©2021 John Wiley & Sons, Inc. 71 2-72 2-73 Low-Dose Creatine Combined with Protein During Resistance Training in Older Men 35 older males (59-77 yrs) were randomized (double-blind) to: • Creatine monohydrate (0.1g/kg/day) • Placebo • 10 weeks of supervised whole-body resistance training 3x/week) Candow et al. (2008). Low-dose creatine combined with protein during resistance training in older men. Medicine and Science in Sports and Exercise, 40(9):1645-1652. BONE RESORPTION CR Values are mean ± SE. Creatine had a greater % decrease vs. PLA after training (p<0.05). Effects of Creatine and Resistance Training on Bone Health in Postmenopausal Women RCT: NCT01057680; clinicaltrials.gov 32 women (54 yrs) were randomized to receive: • Creatine monohydrate (0.1g/kg/day) • Placebo • 52 weeks of supervised whole-body resistance training Chilibeck et al. (2015). Effects of creatine and resistance training on bone health in postmenopausal women. Medicine and Science in Sports and Exercise, 47(8): 1587-1595. BONE MINERAL DENSITY *Participants on creatine lost significantly less BMD (-1.2%) vs. placebo (3.9%) (p<0.05). Clinically Significant A 5% decrease in BMD is associated with 25% greater risk of fracture (Guyatt et al. 2002) Efficacy of Creatine Supplementation and Resistance Training on Area and Density of Bone and Muscle in Older Adults RCT: NCT01057680; clinicaltrials.gov • 53 participants (> 50 yrs of age) • 1 year of supervised resistance training (3x/wk) • Creatine or Placebo: 0.1g/kg/day Candow et al. (2021). Efficacy of creatine supplementation and supervised resistance training on area and density of bone and muscle in older adults. Medicine and Science in Sports and Exercise, 1; 53(11): 2388-2395. BONE STRUCTURE +17 ± 27 mm2 -1 ± 22 mm2 BONE STRUCTURE –5 ± 7 mm2 Δ 0 ± 9 mm2 A 2-Year Randomized Controlled Trial on Creatine Supplementation during Exercise for Postmenopausal Bone Health RCT: NCT02047864; clinicaltrials.gov • 237 participants (mean age: 59 yrs) • 2 years of supervised resistance training (3x/wk) & walking (6x/wk) • Creatine or Placebo: 0.14g/kg/day Chilibeck et al. (2023). A 2-year randomized controlled trial on creatine supplementation during exercise for postmenopausal bone health. Medicine and Science in Sports and Exercise. BONE STRENGTH Femoral neck section modulus (cm3) 1.4 1.35 * 1.3 1.25 1.2 1.15 1.1 1.05 1 0.95 0.9 baseline 12 mo 24 mo creatine baseline 12 mo placebo 24 mo Values are means and SD. *Value at 24 months is less than baseline and 12 months (p<0.01). BONE BUCKLING RATIO ** 14 13 12 11 10 9 creatine placebo **Value at 24 months is higher than baseline (p<0.001) 24 mo 12 mo baseline 24 mo 7 12 mo 8 baseline Femoral neck buckling ratio 15 Clinically Significant Bone strength & buckling ratio are predictors of hip fracture Hip fracture is a main cause of functional impairment BONE SUMMARY The combination of creatine supplementation (≥ 0.1 g/kg/day) and resistance training: 1 2 3 Has some favorable effects on bone area and bone geometric properties Decreases urinary measures of bone resorption Does not increase bone mineral density
