Exercise and the Benefits for Memory and Cognition
The past 2 decades have revoluntionized our understanding of the intimate connection between mind and body. Every year for the past 10-15 years new studies have reported additional evidence for the major benefits physical exercise and physical activities have for our brain health and brain power, in all dimensions of cognition and many areas of emotional health as well. In addition, it is now well established that physical exercise is a key factor promoting neurogenesis, i.e. the creation of new brain cells, especially in the hippocampus. This evidence began with animal studies (see below) and now has been established in ordinary older adults. (see below link and an abstract of major study reported in January 2011 (link to download). In addition, recent studies also clarify that SPECIFIC PHYSICAL activities can be more effective than some cognitive exercises in helping people improve their cognitive skills, including those with cognitive impairments (reference and eventually link to download of cognitive motion study in press).
Among the facts established to date for how physical exercise benefits cognitive health are the following:
Physical exercise:
- Helps blood flow to the brain.
- Increases metabolic capacity, oxygen to brain (McCloskey, 2001).
- Increases cardio-vascular health.
- Decreases inflammation.
- Decreases depression and stress.
- Increased blood flow & oxygen consumption improves cognition in healthy elderly & people with AD (Barnes, 2002; Palleschi, 1996).
- Aerobic fitness reduces brain tissue loss in aging humans (Colcombe, 2003).
- Tai Chi improves cardio respiratory function, immune system, flexibility, balance, mood, thinking and well-being (Li, 2001).
Physical Exercise Reduces Risk of Alzheimer
- Physical exercise reduces risk of AD, dementia and cognitive decline. (Jedrziewski, Lee & Trojanowski 2006; (Laurin, Arch Neurology 2001; Yaffe Arch Int Med 2001, Albert MS 1995, Chyou 1996 ).
- May be especially true for women.
- Some dose effects: more years and greater physical activity increases protection.
- Physical exercise helps us grow new brain cells.
- Physical exercise that involves other people and thinking are the best e.g. dancing, golf, tennis, team sports.
Exercise Improves Cognitive Function in Older Adults-It’s Never Too Late!
- Walking & Stretching with previously inactive older adults (age 60-75)(Kramer Nature 1999):
- Aerobic (walking) but not anaerobic (stretching/toning) improved performance on executive function
- Both improved performance on other cognitive tasks
- Both aerobic and combination (aerobic plus strength training) exercises improved cognitive function (Colcombe & Kramer Psych. Science 2003)
- Combination exercise were more beneficial.
- Exercise sessions must be at least 30 minutes long.
Walking Increases Size of Hippocampus – RCT 120 adults 65+
- Moderate walking 40 minutes, three times/week for 1 year vs. control of stretching
- Increases size of ANTERIOR hippocampus and improves spatial memory; related to increased BDNF
- Hippocampus size measured by MRI scan
- “Exercise training increased hippocampal volume by 2%, effectively reversing age-related loss by 1 to 2 years.” Kramer of Univ. Illinois (control group lost about 1.4 percent )
- Erickson, Kramer et al. Jan 2011 PNAS
Alzheimer Mice Help Us Know Why Physical Exercise Helps Our Brains
- Physical activity (wheel running) and environmental enrichment (other mice & toys) creates new brain cells and doubles number of surviving newborn cells in the hippocampus. (van Praag, Kempermann, Gage, 1999).
- Physical exercise reduces levels of beta amyloid in the brain (Sisodia 2005, Lazarov &Lee 2005; Adlard, Cotman 2005)
- Dose response effect: more exercise on wheel, even less beta amyloid in brains.
- Mice using exercise wheel for 5 months also increased learning speed. (Adlard, Cotman 2005)
Physical Exercise Helps Alzheimer Patients & Carers
- Physical Exercise intervention for AD patients
- Care partner served as “trainer,”
- Improved cognition, ADL function, depression and quality of life
- Improvements in exercise level & results maintained for at least 2 years. (Teri, JAMA, 2003 & 2006)
- Recommended: Use physical exercise with MCI &AD patients and their family carers simultaneously.
