Walking is a great exercise for weight loss, but it seems to be more effective when done right after eating. A 2011 Japanese study found that walking immediately after a meal was more effective for weight loss than waiting up to an hour afterwards. Subjects who went for a brisk, 30-minute walk right after lunch and dinner lost more weight than those who waited to walk. And because walking is a low impact form of exercise, it shouldn’t cause any digestive issues. By iVillage Health