Biomechanics of Resistance Training

Anabolic Exercise for Health Presented by: Dr. Robert Newton Foundation Professor in Exercise Science Edith Cowan University ―Indeed, with the possible exception of diet modification, we know of no single intervention with greater promise than physical exercise to reduce the risk of virtually all chronic diseases simultaneously‖ Booth et al, JAP 2000 Physical Inactivity and Chronic Disease 2 •slow progress, long continuance •individual crosses threshold - ‗‗clinical horizon‘‘ to manifest •mechanisms underlying active long before outwardly affected Chronic Disease 3 ―there has been an epidemic emergence of modern chronic diseases in the latter part of the 20th century‖ ―costs in the USA are now approaching $1 trillion‖ Cost of Chronic Disease Booth et al, JAP 2000 4 •coronary heart disease (atherosclerosis, heart failure, hypertension, and stroke) •obesity •Type 2 diabetes •some cancers •osteoporosis •sarcopenia Examples of Major Chronic Diseases 5 •Medical research and treatment is focused almost entirely on secondary and tertiary prevention •Primary prevention is cheaper, more effective, and far less painful Only fighting half of the battle: being reactive instead of proactive 6 ―the human genome evolved over at least the last 45,000 years within an environment of high physical activity‖ ―the current human genome expects and requires humans to be physically active for normal function and health maintenance‖ Booth et al, JAP 2000 7 We are programmed for physical activity ―There is no pharmacological intervention that holds a greater promise of improving health and promoting independence in the elderly than does exercise‖ Evans & Campbell, Journal of Nutrition, 1993 8 •~ 250,000 deaths per year in the US are premature due to physical inactivity •increases incidence of at least 17 unhealthy conditions •almost all of which are chronic diseases or considered risk factors for chronic diseases Booth et al, JAP 2000 9 Physical Inactivity and Chronic Disease •Physical inactivity ranks second only to tobacco smoking in terms of the burden of disease from risk factors in Australia. •6% (second highest burden for men) of the total burden of disease and injury among males •8% among females (highest burden for women) AIHW: Mathers et al. 1999 1 Physical Inactivity and Chronic Disease…2 •Adult participation in sufficient physical activity for a health benefit declined from 62% in 1997 to 57% in 2000. •Overweight and obesity remains a serious problem, affecting around 65% of men, 45% of women and 22% of children aged 2-17 years. Australian Institute of Health and Welfare Australia’s Health 2002 1 Physical Inactivity and Chronic Disease…3 •leading cause of death among Australians in 2000 •49,741 deaths or 39% of all deaths. •coronary heart disease 53% •stroke 25% •heart failure 5% •peripheral vascular disease 5% Australian Institute of Health and Welfare Australia’s Health 2002 Cardiovascular Disease in Australia 1 How important is physical activity? image from http://www.cotavic.org.au/ “Living Longer Living Stronger” 13 •Loss of muscle mass and function •60% of over 80yrs •Anabolic exercise most effective strategy to prevent or reverse sarcopenia Sarcopenia image from http://www.cotavic.org.au/ 14 •nutrition (under-nutrition and lack of vitamin D) •decreased hormone levels (e.g growth hormone, testosterone) •reduced physical activity particularly high intensity •loss of nerves that innervate the muscles 15 Causes of Sarcopenia image from http://www.cotavic.org.au/ Grounds, M.D. Biogerontology, 2002 •Diabetes is the world's fastest growing disease •It's Australia's sixth leading cause of death •Over one million Australians have it — but 50% are as yet unaware •Every 10 minutes someone is diagnosed with diabetes Diabetes http://www.diabetesaustralia.com.au/ 16 Age-specific prevalence of impaired glucose tolerance, 1999-2000 Age (years) Men% Women% 25–34 2.1 4.9 35–44 4.8 8.5 45–54 8.4 11.2 55–64 14.8 15.2 65–74 20.4 22.9 75+ 25.5 20.7 Source: Dunstan et al. 2001. •Metabolic stage between normal and diabetes •Risk factor for Type 2 diabetes •Also greater risk of heart disease •Much higher in physically inactive and obese •Improved with physical activity and weight reduction 17 Impaired Glucose Tolerance •―In addition to controlling weight, physical activity also improves the body‘s sensitivity to insulin, helping to lower blood sugar.‖ •―Even a single bout of vigorous physical activity will have an immediate effect on insulin sensitivity.‖ Impaired Glucose Tolerance Australian Institute of Health and Welfare Australia’s Health 2002 18 •Exercise improves insulin resistance •Beneficial for preventing and treating type 2 diabetes •Aerobic exercise hindered in older, obese, co-morbid patients •Anabolic exercise safe and effective Resistance Exercise and Diabetes Willey and Singh. Diabetes Care, 2003 19 •It is estimated that appropriate levels of physical activity could prevent 30-50% of new cases of Type 2 diabetes •Benefits for preventing and treating diabetes occur only with regular sustained physical activity patterns Manson & Spelsberg,1994) Physical Activity and Diabetes 20 •Evidence is conclusive •Lifelong physical activity has strong preventative effect •Anabolic exercise - greatest efficacy •Example* •1 year study of strength and endurance training •1.3% increase BMD in training group •1.2% decrease for control Anabolic Exercise and Osteoporosis *Kemmler et al. Archives of Physical Medicine & Rehabilitation, 2003 21 •Increased function e.g. stair climb and descend, chair rise, walking •Reduced ratings of pain •Reduced stiffness •Studies report anabolic exercise to be ―safe, effective and well tolerated in OA patients‖ Anabolic Exercise and Osteoarthritis 22 •Feasible and safe in selected patients with well-controlled RA •Significant improvements in strength, pain, and fatigue Without exacerbating disease activity or joint pain. Anabolic Exercise and Rheumatoid Arthritis 23 Hakkinen, A. 2002 and 2003 •People who are physically inactive are nearly twice as likely to develop colon cancer (Colditz et al. 1997). •Physical activity is also associated with around a 30% reduction in the risk of women of all ages developing breast cancer (Thune & Furberg 2001). Physical activity and cancer risk 24 •Disease and treatment usually results in debilitating fatigue •Research examining exercise programs pre surgery and/or during treatment Increased vigor Reduced muscle and bone loss Enhanced immune function Possible increase survival Positive psychological influences Exercise for Cancer Patients •Prostate and Breast cancer •More accurate detection 25 Anabolic Exercise •Physical inactivity - risk factor •Mechanism unknown •Physical activity – strong positive effect •Slows progression of disease •Ageing population – dementia will become major problem Mental Illness, Dementia, Alzheimer‘s 26 •Epidemiological studies into Alzheimer disease indicates physical activity appears beneficial, as does a diet with high levels of vitamins B6, B12 and folate, while red wine in moderate quantities also appears protective Epidemiology 27 McDowell, I. Alzheimer's disease: insights from epidemiology. Aging-Clinical & Experimental Research. 13:143-162, 2001. Cholesterol •Exercise and nutrition demonstrated effects on: •Lowered TC •Lowered LDL-C •Increased HDL-C •Lowered triglycerides Scranton, R., et al. Predictors of 14-year changes in the total cholesterol to high-density lipoprotein cholesterol ratio in men. American Heart Journal. 147(6):1033-1038, 2004 28 Hypertension •Exercise can lower BP in patients with stage 1 and 2 essential hypertension •Average reduction in BP is 10.5 mm Hg for systolic and 7.6 mm Hg for diastolic BP Kokkinos, P. F., P. Narayan, and V. Papademetriou. Exercise as hypertension therapy. Cardiology Clinics. 19:507-516, 2001. 29 Obesity and Overweight •Combination of exercise and dietary modification is the only effective long-term strategy for controlling body weight 30 •accidental falls for > 65 years $83 million in 2001/02 •1.5 % of health expenditure in WA •cost per fall was $6,500 •Personal and family cost much larger 31 Falls - Cost •Multifactorial •Range of physical activity interventions proven successful •Anabolic exercise reverse loss of muscle strength and slows bone loss – critical function Falls Prevention 32 •Must reverse our concept of ―gentle exercise‖ •To maintain function, reduce chronic disease, enhance quality of life – MUST simulate preindustrial revolution! •Ageism! We need to change our perceptions 33 Deficiencies of some physical activity programs for seniors •Clearly life-long physical activity including resistance exercise is crucial to maintaining optimal structure and function into old age •Primary prevention is imperative! Life-Long Prevention Strategy image from http://www.cotavic.org.au/ 34 Fighting Fit?? http://www.ucomics.com/closetohome/2004/03/07/ 35 Edith Cowan University International enrolments exceed 3,000 with students originating from more than 80 countries. ECU's origins go back to 1902 when it began as a teaching college. Today it is Western Australia's second largest university with almost 23,000 students. The University has three metropolitan campuses in Churchlands, Mount Lawley and Joondalup and a regional campus in Bunbury, a city 200kms south of Perth. More than 330 courses are offered through the five faculties: Business and Public Management; Computing, Health and Science; Communications and Creative Industries, which incorporates the Western Australian Academy of Performing Arts; Community Services, Education and Social Sciences; and the Faculty of Regional Professional Studies 36 •Certificates offered •Personal Training •Women‘s Wellness •Degrees offered •Bachelor of Science (Sports Science) Sport and Exercise Science •Masters and PhD by research •Masters of Exercise Science (Strength and Conditioning) 37 ECU Wellness •Training and certification •Professional development •On-going support 38 Thank You www.ecu.edu.au 39