It's never too late to start. In one study of elderly men and women (mean age 87) who lifted weights three times per week for 10 weeks, strength increased a whopping 113%! The improvement in strength enabled the elderly participants to also walk faster (12% faster than before the study), climb 28% more stairs, and it even caused the muscles in their thighs to increase by more than 2.5%.
Keep your arms almost straight and elbows not quite locked. Raise the handles straight out to the sides and upward to only a couple of degrees above shoulder level without rotating your hands (do not pronate or supinate). Palms should face downward throughout the move. Leading with your elbows, lift only with your deltoid muscles, not with your traps or upper back. Resist during the descent to the starting position. Make sure that the movement is controlled and consistent from the beginning to the end of the set.
Doing at least eight sets per muscle is enough to get some muscle growth but, it can depend on how many reps you're doing. Eight to twelve reps is great, while doing any more may be unnecessary, depending on your body type. Arnold Schwarzenegger had to do 25 sets for squats and about 10 reps, whereas his friend Franco Columbu only did five sets of squats and 10 reps.
Place your hands on the floor slightly wider than shoulder width apart and extend your legs behind you. Brace your core and lower your body until your chest is just above the floor. Take two seconds to lower down and two seconds to press back up. Remember to keep your back flat throughout the movement, your elbows close to the sides of your torso, and to fully extend your elbows at the top of the pushup.
As you have hopefully passed beyond the need to throw obscene amounts of weight around, it's important to realize that not only will you get better results from training by feel, but you will also tend to put less pressure on your joints. Don't get me wrong, it's still crucial to train to failure in the six to eight rep range using compound lifts. Those types of lifts are important, but they are not the focal point of every routine. Use intensity-building techniques such as rest pauses or dropsets, to recruit more muscle fibers.
If you decide to join a gym, know that you're not expected to know how all of the equipment works right off the bat—or what to do with it. Be sure to take advantage of the free orientation so you can learn how to properly use everything that's offered and set up a basic strength-training program. At the gym, machines are preferred for beginners, because they're quite safe: Most require little coordination and offer more stability than free weights while performing the movements.
Believe me, whatever you're doing, you can do more. And no, you won't overtrain; you'll just advance faster when you push your limits. I used to think squatting 405 pounds for 10 reps was great. Now I can do 405 for 25 reps and it's okay, but I know I'm going to get up to 35 reps. Don't be afraid of more weight and more sets; just push a little more each and every workout (even adding 2.5 pounds is great). The greatest athletes in the world have done things that everyone thinks are crazy, but these are the same people breaking world records. Trust me, you can always do more. Train hard, train harder!
This no-holds-barred quest for growth is based on the principle of four: performing four exercises and adding four extra reps to each exercise after the first. Because each lift changes the area of the muscle that receives the most stimuli, the ever-increasing reps shift the demands of the muscle from strength to hypertrophy to endurance to a skin-stretching crescendo that flushes the muscle and celebrates the pump.
The pyramid system of training was in vogue during those days. Bodybuilders using multiple sets per exercise would typically warm up with a light weight and gradually increase the resistance over the 4-5 sets so they were using their heaviest weights for the last sets. As mentioned above, the bodybuilders would start training faster while still using heavy weights as the contest got closer. This would increase the intensity of the workout while still using the same weights because of the decreased rest periods.
Carbohydrates play an important role for bodybuilders. They give the body energy to deal with the rigors of training and recovery. Carbohydrates also promote secretion of insulin, a hormone enabling cells to get the glucose they need. Insulin also carries amino acids into cells and promotes protein synthesis. Insulin has steroid-like effects in terms of muscle gains. It is impossible to promote protein synthesis without the existence of insulin, which means that without ingesting carbohydrates or protein—which also induces the release of insulin—it is impossible to add muscle mass. Bodybuilders seek out low-glycemic polysaccharides and other slowly digesting carbohydrates, which release energy in a more stable fashion than high-glycemic sugars and starches. This is important as high-glycemic carbohydrates cause a sharp insulin response, which places the body in a state where it is likely to store additional food energy as fat. However, bodybuilders frequently do ingest some quickly digesting sugars (often in form of pure dextrose or maltodextrin) just before, during, and/or just after a workout. This may help to replenish glycogen stored within the muscle, and to stimulate muscle protein synthesis.