The best time to work out every day is in the evening 19:30-21:00, this time fitness has the following three major benefits: First, at this time, such as outdoor aerobic exercise air index is fresher, the dust mites, microorganisms, haze and other activities in the air is lower, so it is a better air quality and air index time. Second, at this time, plants are no longer photosynthesizing, plants will release carbon dioxide when photosynthesizing, absorbing too much oxygen, so the oxygen content of the outdoors is higher during this time. Third, this is the time when the body’s basal metabolic rate is low, after exercise will significantly increase the metabolic rate and basal metabolic rate, which has a special good effect on weight loss and fat loss. Fourth, this time is 2-3 hours away from sleep, after the fitness will help to improve the quality of sleep.