New research suggests that even a simple exercise program might help older people with light, or mild, memory problems.Doctors have long advised patients to do physical activity to help keep their brains healthy.But the U.S. government-supported research marks the longest study of whether exercise makes any difference once memory starts to decline.Researchers found around 300 inactive older adults with memory changes called mild cognitive impairment (MCI).MCI is a condition that sometimes comes before Alzheimer’s disease.Half of the older adults did aerobic exercises, and the rest did stretching and balance movements that raised their heart rates a little.People in both groups got attention from trainers who worked with them at youth organization centers called YMCAs around the United States.When COVID-19 shut down gyms, the trainers helped the study participants keep moving at home by video calls.After a year, testing of mental activity showed neither group had worsened, said lead researcher Laura Baker of Wake Forest School of Medicine in the state of North Carolina.