What’s “best” for one is not always best for another. Some people weight train very intensively and aerobically. For them, weight training is more aerobic than their “cardio” workout on the treadmill or stationary bike.
For people who are trying to lose weight, we have seen the best results with an emphasis on aerobic activity. After five to six weeks of moderate aerobic exercise like walking, we recommend adding resistance training. That can be as simple as wearing or carrying weights while walking or doing light weight range-of-motion exercises. As one becomes more fit, they can increase their strength training regimen to incorporate eight to ten exercises, targeting all major muscle groups. Each exercise should be performed for two to four sets. Reps (the number of times each exercise is performed in one set) can vary widely – from five to more than fifty – depending on the weight, your ability, and your exercise goal.
There are a lot of books on the market with good descriptions and illustrations. ‘The New Encyclopedia of Modern Bodybuilding : The Bible of Bodybuilding’ by Arnold Schwarzenegger, published in January 2000 is a classic and appropriate for men and women.