One key to getting the most out of your workouts is to avoid exercising with a friend. While many experts will say exercising with a friend can help motivate you, it can often do more harm than good. For example, the tendency could be to spennd too much time talking and socializing with the person, and not spending enough time focused on your own workout.
Eat more when you are working out. When a body works out it burns more calories because the shifting muscles need energy to stretch. They stretch by utilizing your body's fat and sugar stores as energy. If you simply work out and forget to eat it can be negative to your gains, resulting in malnutrition and atrophy of the muscles.