A balanced, moderate approach is best for most people for long-term weight management. So have that apple, and offer one to your co-workers. I work out three to four times a week and watch what I eat, but it has become increasingly more difficult to stay fit. Your body changes over time, and it is good to re-evaluate your diet periodically, because your needs can change. If your weight is creeping up, keep an accurate food diary for a week.
Weight training builds muscles and therefore increases metabolism.
Aerobics burns fat. Try to vary your aerobic routine so you can use different muscle groups to help keep your metabolism up. I dropped the weight I needed, as well as the use of the drug. With regular exercise I successfully kept the weight off for more than a year. My job situation changed, and so did my exercise patterns.