Exercising abdominal muscles should not be done on an empty stomach before eating in the morning, nor should it be done immediately after eating. The time to exercise abdominal muscles should be 30 minutes to an hour apart from the time to eat.

After a full meal, gastrointestinal activity is enhanced, digestive juice secretion is increased, and the amount of blood needed in the process of digesting food is also increased. At this time, if strenuous exercise is carried out immediately, gastrointestinal activities and secretion of digestive juice will be inhibited due to the adjustment of nerve and body fluid factors, so that the blood supply in the gastrointestinal tract will be relatively reduced, and more blood will be supplied to the motor organs, which will lead to the weakening of gastrointestinal digestive function and easily cause gastrointestinal discomfort and pain, and even indigestion.

Similarly, you should eat regularly after exercise, because the center that manages muscle activity is in a state of high excitement during exercise, and at the same time, the digestive organs are inhibited, and the activities of the digestive organs will take some time to recover. Therefore, generally, after a long period of strenuous exercise, don't want to eat immediately, and rest for about 30 minutes before eating.