Those micro-tears that are such a key factor for muscle-building need rest to rebuild themselves and grow stronger. When do they do that? When you’re asleep! “You have to rest and feed your muscles between workouts or you will tear them down and they will become weaker,” says Olson. “Over time, you run the risk of over-training, which can result in injury, and possibly even more sleep troubles.”
I learned from this to focus on the body weight exercises. I never understood why I could lift a lot of weight, but felt weak when it came to dips, pull ups, push ups etc. Normally I spend 2 hours in a gym: 20 min jogging, 80 min lifting, 20 min jogging, 5 days a week. After reading this I’m excited to incorporate HIIT training in addition to mobility training on my off days, because I think I was wasting a lot of time and effort. I can push way harder on lifting days without the jog beforehand, so I’ll also be able to make the most of 60 minutes…
How to do it: Begin with one foot firmly planted in front of you with your other leg extended back. Keep balance by putting your weight in the ball of your front foot and the back heel of your back foot. Hold a dumbbell in either hand, arms at your sides. Or, place a resistance band under the foot of your working leg, up, and around the same shoulder. Stand tall and bend your front working leg to approximately 90 degrees, keeping your knee directly over your ankle so it doesn’t over-extend. Return to the start position and repeat. Do both sides.
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 the 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.
Note that this recommendation is for total weekly volume, which means it would need to be divided up based on how many times you’re training each muscle group per week. So, for example, someone training everything twice per week would do 30-70 reps for each bigger muscle group in each of those workouts, and 15-35 reps for each smaller muscle group in each of those workouts.