Showing posts with label exercise. Show all posts
Showing posts with label exercise. Show all posts

Sunday, October 19, 2008

Exercise and Brain Aging

There is now abundant research pointing to the beneficial effects of aerobic exercise on cerebral health. This recent study finds that taking up exercise can improve cognition and cerebral health. There is a striking relationship between cardiovascular and cerebral health. The reason for this is obvious: the brain consumes approximately 20% of our oxygen intake, so maintaining maximal blood supply to the brain is critical. One of the reasons Ginkgo Biloba works is because it reduces platelet activating factor, thereby improving cerebral circulation.

Exercise and do it often. You don't have to run marathons, in fact intense exercise can do more harm than good. Light exercise is okay but it is important to push yourself, just going for a casual walk is good but going for a brisk walk is much better.

Exercise effects on cognitive and neural plasticity in older adults
Kirk Erickson and Arthur F Kramer
British Journal of Sports Medicine (2008).
The abstract:

Older adults frequently experience cognitive deficits accompanied by deterioration of brain tissue and function in a number of cortical and subcortical regions. Because of this common finding and the increasing aging population in many countries throughout the world, there is an increasing interest in assessing the possibility that partaking in or changing certain lifestyles could prevent or reverse cognitive and neural decay in older adults. In this review we critically evaluate and summarize the cross-sectional and longitudinal studies that assess the impact of aerobic exercise and fitness on cognitive performance, brain volume, and brain function in older adults with and without dementia. We argue that six-months of moderate levels of aerobic activity are sufficient to produce significant improvements in cognitive function with the most dramatic effects occurring on measures of executive control. These improvements are accompanied by altered brain activity measures and increases in prefrontal and temporal grey matter volume that translate into a more efficient and effective neural system.

Tuesday, September 16, 2008

Exercise is not Enough to Ward off Type 2 Diabetes:

Numerous studies now indicate that just going to the gym a few times a week is not enough to prevent type 2 diabetes. Long hours sitting, as work so often demands, is a significant risk factor even if we engage in regular exercise. This study highlights the risk of long hours of sitting and provides some insight into the underlying physiological processes that can occur from such inactivity.

As a general rule it is a good idea to stand up every 30 minutes. No, not for another cup of coffee, but to go for a quick walk. Plan your work day to allow this type of break.

The news item can be read here.



Below is the abstract details.

Diabetes Care 31:661-666, 2008
Breaks in Sedentary Time. Beneficial associations with metabolic risk



OBJECTIVE—Total sedentary (absence of whole-body movement) time is associated with obesity, abnormal glucose metabolism, and the metabolic syndrome. In addition to the effects of total sedentary time, the manner in which it is accumulated may also be important. We examined the association of breaks in objectively measured sedentary time with biological markers of metabolic risk.

RESEARCH DESIGN AND METHODS—Participants (n = 168, mean age 53.4 years) for this cross-sectional study were recruited from the 2004–2005 Australian Diabetes, Obesity and Lifestyle study. Sedentary time was measured by an accelerometer (counts/minute–1 < 100) worn during waking hours for seven consecutive days. Each interruption in sedentary time (counts/min 100) was considered a break. Fasting plasma glucose, 2-h plasma glucose, serum triglycerides, HDL cholesterol, weight, height, waist circumference, and resting blood pressure were measured. MatLab was used to derive the breaks variable; SPSS was used for the statistical analysis.

RESULTS—Independent of total sedentary time and moderate-to-vigorous intensity activity time, increased breaks in sedentary time were beneficially associated with waist circumference (standardized β = –0.16, 95% CI –0.31 to –0.02, P = 0.026), BMI (β = –0.19, –0.35 to –0.02, P = 0.026), triglycerides (β = –0.18, –0.34 to –0.02, P = 0.029), and 2-h plasma glucose (β = –0.18, –0.34 to –0.02, P = 0.025).

CONCLUSIONS—This study provides evidence of the importance of avoiding prolonged uninterrupted periods of sedentary (primarily sitting) time. These findings suggest new public health recommendations regarding breaking up sedentary time that are complementary to those for physical activity.

Abbreviations: AusDiab, Australian Diabetes, Obesity and Lifestyle