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Can resistance training increase bone mineral density in osteoporotic women?. Tricia Backus and Christa Roessner. Resistance Training . Exercise during which a muscle contracts just a few times against a heavy load or with high tension.
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Can resistance training increase bone mineral density in osteoporotic women? Tricia Backus and Christa Roessner
Resistance Training • Exercise during which a muscle contracts just a few times against a heavy load or with high tension. • Distinct from endurance training during which muscles contract against little or no resistance. (Evans, 2005)
What is Osteoporosis? • A systemic skeletal disease • More prevalent among women • One in two women aged 50 and over will have an osteoporosis-related fracture in their lifetime • After age 30 • Deliberating effect on independence and quality of life • 10 million Americans (ACSM, 2006)
What is low bone mineral density? • How it is measured • DEXA video • BMC results are put into T score to determine risk (mayoclinic.com)
How to Prevent / Treat • Supplements • Calcium: • 500mg and 1500mg • Alendronate: • 10mg • Prescription medicine • Lifestyle • Healthy diet • Exercise
How Does BMD Increase? • Multiple-Hormone System • Blood calcium levels (Robergs & Roberts, 1997). • Physical Stress • Bone tissue must have daily stimulus to increase/maintain BMD (Hamill, Knutzen 2003) • Stresses help activate the osteoblasts and favor bone deposition (Hamill, Knutzen 2003)
Types of Exercise looked at • Strength • Flexibility • Agility • Power
Power vs Strength • 53 postmenopausal women • Resistance training, gymnastics session, and home training over 12 months • Strength: used slow movements • Power: used fast movements • Power= Strength/Time • Used calcium and Vit. D • Power training is more effective in reducing bone loss (significant at p<0.05) (Stengel, 2005)
Hormone Replacement Therapy • 28 women on HRT • 75 and older • Physical Frailty • 9 months of supervised or home exercise • PT, resistance, and endurance training • Relatively vigorous exercise training significantly increases lumbar spine BMD • No control group (Villareal, 2003)
Frequency/Duration • Resistance Training: • 2x/week; 50 mins.(Liu-Ambrose, 2005) • 2x/week; 35 mins. (Judge, 2005) • 2x/week; 50 mins. (Lohman, 1995) • 2x/week; 45 mins. (Braith, 2003) • 3x/week; 60 mins. (Pruitt,1992) • 3x/week; 90-100 mins. (Villarel, 2003) • 2x/ week; 60 mins. (Stengel, 2005) • Power Training: • 2x/week; 60 mins. (Stengel, 2005) • Agility Training: • 2x/week; 50 mins. (Liu-Ambrose, 2005) • Flexibility Training: • 2x/week; 50 mins. (Liu-Ambrose, 2005) • 2x/week; 60 mins. (Villareal, 2003)
Intensity • Resistance training: • 2 sets 10-15 reps. 50-60% 1 RM (Liu-Ambrose, 2005) • 1-3 Sets 10-12 reps. (Lohman, 1995) • 2 sets 10-15 reps. 50-60% 1 RM (Braith, 2003) • 1-3 sets 12 reps. ~65% 1 RM (Villareal, 2003) • Power Training: • 2 sets. 10-15 reps. (fast movements) (Stengel, 2005) • Agility Training: • Varied (relay races, obstacle courses, dance) (Liu-Ambrose, 2005)
Diet • A high ratio of dietary animal to vegetable PRO increases the rate of bone loss and the risk of fracture in postmenopausal women. • More rapid femoral neck bone loss • Suggest an increase in plant PRO and a decrease in animal PRO to prevent (Selmeyer, 2001 Sports Nutrition Workshop)
Helen Zechmeister, Age 91, Weight Lifter (http://nihseniorhealth.gov)
Summary of Findings • Largest increases were shown in subjects using hormone replacement therapy or Alendronate in addition to resistance exercise • Power training was shown to be best form of resistance training (Stengel, 2005) • May not be best for older populations • Therefore, resistance training still effective • Exercise prescription: • Frequency: 2-3x/week • Duration: 60 mins. • Intensity: 50-65% 1 RM • 2 sets 10-15 reps. • Diet: protein helps to decrease bone loss (Selmeyer, 2001)
References • Liu-Ambrose T., Khan K, Eng J, Lord S, Lentle B, McKay H. Both resistance and agility training reduce back pain and improve health-related quality of life in older women with low bone mass. Intl. Osteoporosis Foundation 2005; 16: 1321-1329 • Villareal D, E Binder, K Yarasheski, et al. Effects of Exercise Training Added to Ongoing Hormone Replacement Therapy on Bone Mineral Density in Frail Elderly Women. J Am Geriatr 2003; 51: 985-990 • Stengel SV, W Kemmler, R Pintag, et al. Power training is more effective than strength training for maintaining bone mineral density in postmenopausal women . J Applied Phys 2005; 99(1): 181-188 • Kelley GA, KS Kelley, & ZV Tran. Resistance training and bone mineral density in women: a meta-analysis of controlled trials. Am J Physical Med and Rehab 2001; 80(1): 65-77 • Sports Nutrition Workshop: Nutrition and Exercise. Nancy Clark MS RD & William Evans PhD. Columbus, Ohio. Dec 2-3 2005 • Judge J, et al. Home-based resistance training improves femoral bone mineral density in women on hormone therapy. Osteoporosis Intl. 2005; 16 (9): 1096-1108 • Lohman T. et al. Effects of resistance training on regional and total bone mineral density in premenopausal women-a randomized prospective study. Journal of Bone and Mineral Research 1995; 10 (7): 1015-1024
References (cont.) • Braith RW et al. Resistance Training and alendronate reverse glucocorticoid-induced osteoporosis in heart transplant recipients. Journal of heart and lung transplantation 2003; 22 (10): 1082-1090. • Pruitt LA et al. Weight training effects on bone-mineral density in early postmenopausal women. Journal of bone and mineral research 1992; 7 (2): 179-185. • Hamill, Joseph and Knutzen, Kathleen. Biomechanical Basis of Human Movement. Lippincott Williams & Wilkins, Philadelphia, PA 2003. • ACSM Guidelines for Exercise Testing and Prescription. Lippincott Williams & Wilkins: 2006. • www.familydoctor.com • www.pinksunrise.com • www.imagins.com • www.mayoclinic.com • (Robergs & Roberts, 1997).http://www.unm.edu/~lkravitz/Article%20folder/bonemass.html