What could be the reasons for my body not getting bigger despite efforts?

If you are trying to build muscle but not seeing results, several factors could be at play.

Exercise Routine: According to research, how often you exercise and the type of exercises you do are very important. If you are not exercising enough, or not doing the right kind of exercises, your muscles might not grow as much as you'd like.

Nutrition: Eating enough food, especially protein, is crucial for muscle growth. Without the right nutrients, your body won't have what it needs to build muscle.

Body's Limits: Everyone's body is different, and some people might find it harder to gain muscle due to their genetics.

In summary, to increase muscle size, you need to focus on exercising regularly, eating well, and understanding your body's natural limits. Try changing your exercise routine or diet if you are not seeing the results you want.