The first one may be an air bike. This method can be said to be known to every girl. Just lie flat on the bed, and then it's not too difficult and relatively easy to operate.
However, many girls are wrong when selling bicycles short. They should use the right methods, mainly to control the speed. If the speed is too fast, it will not work, and the exercise effect will not be achieved. Be sure to do it slowly, don't use inertia, be sure to straighten your toes and keep your legs in a state of exertion. If you feel sore at this time, you must stick to it, otherwise you can't improve your body shape.
Another way is to roll your belly, which will make your belly flatter, so that you won't have a protruding belly when you wear clothes, and there will be no swimming ring in early summer. It is worth noting that you should never do sit-ups desperately. According to scientific proof, sit-ups will do harm to people's spine now, and the exercise of abdominal muscles and core muscles is not as good as belly rolling, so everyone tries to choose belly rolling instead of sit-ups.
The third trick is scissors leg, which is also made for stovepipe, and sometimes it is even more effective than air bike. Pay attention to stretching after finishing, and then you can put your legs upside down on the wall, which will help blood circulation in your legs and improve leg edema.