You will start with 1 set of 12 repetitions for each of 9 exercises for the first week. At workout session 8, you should have progressed to 3 sets of 12 repetitions for each exercise. The weight you choose to start with will be sufficient to perform a set of 12 repetitions to failure with good form, which means that the twelfth repetition is pretty much the most you can do without resting. This is called 12RM (repetition maximum).
This period also saw the rise of anabolic steroids in bodybuilding and many other sports. In bodybuilding lore, this is partly attributed to the rise of "mass monsters", beginning with Arnold Schwarzenegger, Sergio Oliva, and Lou Ferrigno in the late 1960s and early 1970s, and continuing through the 1980s with Lee Haney, the 1990s with Dorian Yates, Ronnie Coleman, and Markus Rühl, and up to the present day. Bodybuilders such as Greg Kovacs attained mass and size never seen previously but were not successful at the pro level. Others were renowned for their spectacular development of a particular body part, like Tom Platz or Paul Demayo for their leg muscles. At the time of shooting Pumping Iron, Schwarzenegger (while never admitting to steroid use until long after his retirement) said that "you have to do anything you can to get the advantage in competition". He would later say that he does not regret using anything.
Getting comfortable with a steady running routine is definitely something to be proud of, but when you're on that cardio grind day-in and day-out, you might be ready to change things up and take on a new challenge. Time to throw some strength training into the mix. It can be a little intimidating at first if you don't know where the hell to start, but understanding the basics can help you feel confident in your refreshed fitness routine.
Warmups are important to get blood flowing to heart, lung, and muscles and lubricating (synovial) fluid loosening the joints ready for action. Each weights exercise should include a warmup with light weights and practicing the same form as for the workout weight. Sixty percent of your workout weight is about right for warmups. Stretching is not so important before exercise and is better performed after exercise. Some light stretches will do no harm.
On January 16, 1904, the first large-scale bodybuilding competition in America took place at Madison Square Garden in New York City. The competition was promoted by Bernarr Macfadden, the father of physical culture and publisher of original bodybuilding magazines such as Health & Strength. The winner was Al Treloar, who was declared "The Most Perfectly Developed Man in the World". Treloar won a $1,000 cash prize, a substantial sum at that time. Two weeks later, Thomas Edison made a film of Treloar's posing routine. Edison had also made two films of Sandow a few years before. Those were the first three motion pictures featuring a bodybuilder. In the early 20th century, Macfadden and Charles Atlas continued to promote bodybuilding across the world. Alois P. Swoboda was an early pioneer in America.
Bodybuilders often split their food intake into 5 to 7 meals of equal nutritional content and eat at regular intervals (e.g. every 2 to 3 hours). This approach serves two purposes: to limit overindulging in the cutting phase, and to allow for the consumption of large volumes of food during the bulking phase. Eating more frequently does not increase basal metabolic rate when compared to 3 meals a day. While food does have a metabolic cost to digest, absorb, and store, called the thermic effect of food, it depends on the quantity and type of food, not how the food is spread across the meals of the day. Well-controlled studies using whole-body calorimetry and doubly labeled water have demonstrated that there is no metabolic advantage to eating more frequently.
When lifting it is essential to focus your mind completely on the muscle group you are attempting to work on. This makes sure that you are actually using the target muscle to lift the weight rather than accessory muscles or even momentum. This skill will develop with time, and as you progress in making that mind to muscle connection, your workouts will become much more productive and efficient.