PHYSICAL EXERCISE MAKES YOUR BRAIN WORK BETTER
Love it or hate it, bouts of physical activity can have potent effects on your mood. The runner’s high – that feeling of elation that follows intense exercise – is real. It may not be due to an “endorphin rush”, though. Levels of the body’s homemade opiate do rise in the bloodstream, but it’s not clear how much endorphin actually gets into the brain. Instead, recent evidence points to a pleasurable and pain-killing firing of the endocanna-binoid system: the psychoactive receptor of cannabis.
When anxiety levels rise, you tense up, your heart races and your attention narrows to a slit. This shift to “fight or flight” mode is automatic, but that doesn’t mean it’s wholly out of your control. Yoga teaches the deliberate command of movement and breathing, with the aim of turning on the body’s “relaxation response”. Science increasingly backs this claim. For example, a 2010 study put participants through eight weeks of daily yoga and meditation practice. In parallel with self-reported stress-reduction, brain scans showed shrinkage of part of their amygdala, a deep-brain structure strongly implicated in processing stress, fear and anxiety.
The evidence that staying physically fit keeps your brain healthy into old age is especially compelling. Most concrete is the link between aerobic fitness and cognitive preservation. Workouts needn’t be extreme either: 30-45 minutes of brisk walking, three times a week, can help fend off the mental wear and tear and delay the onset of dementia. It pays to get used to regular exercise early, though. The protective effects are clearest before the cognitive signs of old age kick in.
Exercises to improve balance, coordination and agility made a clear impact on the brain structure and cognitive function of a large group of German elderly people. Twice weekly sessions of weightlifting can have a visible neurological impact. Dancing may also be restorative for ageing brains. Just an hour of dance a week, for six months, did little for elderly participants’ aerobic capacity, but the physical and social stimulation bolstered their cognitive well being.
Researchers are still teasing out the critical factors that make exercise such a potent brain tonic. Prime suspects include increased blood flow to the brain, surges of growth hormones and expansion of the brain’s network of blood vessels. It’s also possible that exercise stimulates the birth of new neurons. Until recently, few believed this could happen in adult human brains.
28 May, 2017