The first serious consequence is to gain weight. Eat less and eat more, and you will definitely get fat.
The second serious consequence is that muscles will shrink. Muscles are used and discarded. Muscle will grow when used, and will shrink when not used.
The third serious consequence, happiness will decline. Sports will affect happiness. Is it ridiculous? Of course not. People who don't exercise always feel that their physical function is declining, getting worse and worse, getting older and older, and their lives are not as arbitrary as before. You know, being able to control your body independently is also an important part of feeling happy in life.
The fourth serious consequence is bone loss.
With the increase of age, bone loss is inevitable, but the rate of decline can be controlled. There is a big difference between sprinkling a drop of water a day and sprinkling a bowl of water a day. So, what affects the speed of bone loss? It's sports! If you insist on exercise during the process of bone loss, exercise will always stimulate bones. Bone is a very clever organ. If you use it every day, it must support you and be constantly stimulated by this support. It must become stronger to withstand your use. Therefore, people who exercise for a long time will have high bone density and be strong, so that the calcium they eat can be absorbed.
If you eat delicious food in bed every day and don't absorb it at all, your bones will still lose quickly, so the strength of your bones still depends on practice. If there is no physical exercise, bone loss will be rapid and osteoporosis will be more likely. Other serious consequences are well known, so I won't go into them one by one. Tell you so much, just tell you a little. Even if there is no special physical exercise opportunity and time, do more activities.