Aerobic exercise can improve memory function and maintain brain health as we are getting older. Researchers examined the effects of aerobic exercise on a region of the brain called the hippocampus, which is critical for memory and other brain functions. Brain health decreases with age, with the average brain shrinking by approximately five per cent per decade after the age of 40.
Studies in mice and rats have consistently shown that physical exercise increases the size of the hippocampus but until now evidence in humans has been inconsistent. The researchers systematically reviewed clinical trials which examined the brain scans of different people before and after aerobic exercise programs or in control conditions.
The participants included a mix of healthy adults, people with mild cognitive impairment such as Alzheimer’s and people with a clinical diagnosis of mental illness including depression and schizophrenia. Ages ranged from 24 to 76 years with an average age of 66. They examined effects of aerobic exercise, including stationary cycling, walking, and treadmill running. The length of the interventions ranged from three to 24 months with a range of 2-5 sessions per week.
Result showed that while exercise had no effect on total hippocampal volume, it increases the size of the left region of the hippocampus in humans. When you exercise you produce a chemical called brain-derived neurotrophic factor BDNF, which may prevent age-related decline by reducing the deterioration of the brain. Exercise maintains the program for the brain, prevents ageing-related neurodegenerative disorders such as Alzheimer’s and dementia.