Exercise & Health

A study involving 97 healthy older adults (65-89) has found that those with the “Alzheimer’s gene” (APOe4) who didn’t engage in much physical activity showed a decrease in hippocampal volume (3%) over 18 months. Those with the gene who did exercise showed no change in the size of their hippocampus, nor did those without the gene, regardless of exercise. Physical activity was classified as low if the participant reported two or fewer days per week of low intensity activity, such as no activity, slow walking or light chores.

Brain scans have revealed that those who regularly practiced yoga had larger brain volume in the somatosensory cortex (maps the body), superior parietal cortex (involved in directing attention), visual cortex (perhaps because of visualization techniques), hippocampus, precuneus and the posterior cingulate cortex (the last two involved in our concept of self).

http://www.scientificamerican.com/article/how-yoga-changes-the-brain/

A mouse study has found that long-term physical activity increased levels of two proteins in the mitochondria of their heart. It’s thought this might help explain why regular exercise improves cardiovascular health.

http://www.eurekalert.org/pub_releases/2014-02/cfgr-etc021114.php

Several recent studies add to the evidence that physical fitness boosts cognitive processing in children.

Physically fit kids have better white matter

A brain imaging study involving 24 9- and 10-year-olds has found that physical fitness was associated with significant differences in the integrity of several white-matter tracts in the brain: the corpus callosum, the superior longitudinal fasciculus, and the superior corona radiata. All of these are involved in learning and memory. The differences are associated with faster and more efficient nerve activity.

Data from the American National Health and Nutrition Examination Survey (NHANES) III, involving 3,659 individuals (men aged 55+; women 65+), has found that the more muscle mass older adults have, the less likely they are to die prematurely. The findings add to the growing evidence that overall body composition — and not the widely used body mass index (BMI) — is a better predictor of mortality.

http://www.eurekalert.org/pub_releases/2014-03/uoc--oab031314.php

An 11-week trial involving 54 young, healthy men and women engaging in an endurance training program, has found that markers for the production of new muscle mitochondria only increased in the group not taking vitamin C and E supplements. It’s possible that high doses of vitamins C and E act as antioxidants and take away some of the oxidative stress needed to develop muscular endurance.

http://www.eurekalert.org/pub_releases/2014-02/w-vca013014.php

A mouse study has found that obese mice had high levels of interleukin 1 in both their blood and their brains, and this was associated with:

• high levels of inflammation,
• low levels of a biochemical important to synapse function, and
• impaired cognitive function.

Moreover, when fat was removed from the obese mice, interleukin levels dropped dramatically, and cognitive performance improved.

Putting obese mice on an exercise program had a similar effect, even though they didn’t lose weight — but they gained muscle and lost fat.