Aerobic exercise after or before meals

There is no universal optimal choice, it just needs to be completely adapted to your exercise goals, basic health conditions and daily routine.

I have been a fitness instructor for the past 6 years, and this question has been asked by members no less than 800 times. There is a young girl who just went to work and climbed the stairs in the morning to burn fat. She climbed up until her eyes were black and leaned against the wall to send me a message. There is also a retired aunt who went to square dance immediately after dinner. After dancing, she came back with a bloated stomach and could not sleep for half the night. I have seen people go to both extremes.

The popular saying "Fasting aerobic fat-burning efficiency is high" that has been widely circulated on the Internet is really not made up by marketing accounts. Indeed, sports nutrition research has confirmed that the human body has less glycogen reserves in a fasting state, and the proportion of fat participating in energy supply will be 20% to 30% higher than after a meal. But this is only half the story - if you don’t have high muscle mass and do aerobics on an empty stomach for more than 40 minutes, the proportion of your body that breaks down muscles for energy will also increase. By then, you won’t have lost much fat, but you will first have lost the muscles that support metabolism, and it will become more difficult to lose weight. There are also people who have problems with hypoglycemia and anemia, and they should avoid doing aerobics on an empty stomach. They are really prone to fainting on the road.

Wouldn't it be better to do it after a meal? Neither. For most office workers who have a regular schedule, taking an hour's break after eating is the easiest option to stick to. For example, if you work from 9 to 6, have a meal on the way after get off work, go home and rest until 7:30, change clothes and go downstairs to run 3 kilometers, or dance to Pamela for 20 minutes, you will not have to force yourself to get up half an hour early and feel sleepy, nor will you be so hungry that you have no energy when practicing. And for people with unstable blood sugar, or people who need to ensure calories during the muscle-building period, aerobic exercise after meals can also help reduce blood sugar peaks after meals and prevent excess calories from being converted into fat accumulation. I have contacted several members with prediabetes who insist on walking slowly for 20 minutes half an hour after meals. After three months, their blood sugar levels after meals have dropped by 20%, which is better than simple sugar control.

The preferences of different sports circles are actually very different, and it is impossible to say who is right and who is wrong. Several friends I know who are preparing for bodybuilding competitions basically don’t do aerobics on an empty stomach. Even if they want to clean up fat, they always eat their pre-workout meal (usually a piece of toast with a spoonful of peanut butter) and rest for half an hour before doing aerobics, for fear of losing the hard-earned muscles. ； But friends who often run marathons are just the opposite. Most people are used to running in the morning on an empty stomach. After practicing for several years, their bodies have already adapted to the mode of fat supply. They don’t feel tired after running 10 kilometers. However, if they run after eating, they will feel that their stomachs are shaking and the probability of gas problems is much higher.

I actually try both. I can’t get up at all on weekdays. I usually ride a spinning bike for 40 minutes an hour and a half after dinner. My digestion is about the same. After the ride, I feel refreshed. I go home, take a shower and fall asleep. The quality of my sleep is much better.； If I don’t have to rush on weekends, I’ll get up early and run 3 kilometers on an empty stomach in a park near my home. After the run, I’ll buy a soy-milk bun for breakfast, and I won’t feel any discomfort.

To be honest, don’t worry about before or after meals. Don’t touch the two red lines and nothing will happen: One is not to be so hungry that your hands and feet are weak and you are sweating when you practice hard. It is really easy to get into danger. I saw a girl at the gym last year who ran 5 kilometers in the evening without eating in order to lose weight quickly. She fell down after just two laps and broke her chin and needed three stitches. It was not worth it.； The other is when you have just finished eating a big meal that is heavy in oil and salt, such as hot pot or barbecue. Do not immediately do strenuous exercise such as jumping or running. Your stomach will be full and shaking around can easily cause stomach cramps. The pain can really make you break into a cold sweat. I have done it once, and I don’t want to experience it again in my life.

In fact, there is really no need to be tied down by the "standard answers" on the Internet. If you don't feel uncomfortable getting up early, want to brush fat quickly, and you don't have hypoglycemia problems, it's absolutely fine to do it on an empty stomach before meals.； If you can't get up, it's more comfortable to move after eating. There's no harm in doing it after a meal. The time that makes you willing to stick to it for a long time is the time that suits you best.