It’s hard sometimes to be motivated about working out. I mean for some of us it actually makes us physically ill. But let me suggest something. If you are actually getting physically ill from working out, you are going too hard, starting too fast. I knew a woman with a type of bulimia in college. Essentially she would eat, but then she would run until she threw up. It was extremely unhealthy, and she had to really cut back on workouts and control things to get past it. But while you may not be meaning to go to this extreme, you may be inevitably doing it to yourself. In addition, remember to eat before you workout as you are burning off more calories and may be experiencing low blood sugar. In extreme cases, people have experienced what is essentially understood as a severe breakdown of the skeletal system. The skeletal system is sturdy and hard when we are young yes. But still, it can take too much pressure and you will end up hospitalized. In less severe cases, when you are still doing too much against your body, you will still feel sick as you might now. So cut your workout in half and see if that helps. It might not do the whole job at which time you will have to further tone down your workout. I suggest always starting out small, and remember the part about blood sugar.