How much exercise is enough? Apparently, it depends on your goals and that of your care provider. A study from the UK in the journal Neuroscience and Biobehavioral Reviews concludes low to moderate physical activity reduced the amount of depression and anxiety by one-quarter. The data was collected from around the world. The strong benefit for reduced depression came from activities such as gardening, walking and golf. However, this was not strongly observed from high-intensity exercise. An explanation is that moderate exercise can improve mental health through biochemical reactions, whereas high-intensity exercise may worsen stress-related responses in some individuals.