Still, it's important to realize that for everyone, at a certain point, building muscle becomes more difficult. "We all have an endpoint to our genetic potential," Matheny says. "Someone who is starting strength training for the first time can build muscle with a lower percentage of their 1RM [the maximum amount of weight they can lift one time] than a more tenured athlete. The longer you train and the closer you to get to your natural potential, the more specific you need to get with your training and nutrition to keep making progress. And that week-by-week progress will likely be much smaller than it once was."
A child’s ability to regenerate high energy phosphates during high intensity exercise is less than that of an adult. Due to this, creatine supplementation may benefit the rate and use of creatine phosphate and ATP rephosporylation. However, performance in short duration high-intensity exercise can be improved through training therefore supplementation may not be necessary .
Sports where strength training is central are bodybuilding, weightlifting, powerlifting, and strongman, highland games, hammer throw, shot put, discus throw, and javelin throw. Many other sports use strength training as part of their training regimen, notably: American football, baseball, basketball, football, hockey, lacrosse, mixed martial arts, rowing, rugby league, rugby union, track and field, boxing and wrestling.
A great analogy that I like is that the balance between training and recovery is like digging a hole. Each time you lift, you dig yourself deeper and make it harder to climb out of the hole. To get back out again, you have to fill in the hole to return to ground level, and the only way to fill it is with food and rest. If you overdo it in the gym by pushing too hard, you won’t be able to train as often or at a high capacity. Eventually, you’ll get injured.
The body's pool of creatine can be replenished either from food (or supplements) or through synthesis from precursor amino acids. Dietary sources include beef, tuna, cod, salmon, herring, and pork . The normal dietary intake of creatine is 1-2 g/day, although vegetarians may consume less [3,4]. Dietary creatine is absorbed from the intestines into the bloodstream. If the dietary supply is limited, creatine can be synthesized from the body stores of the amino acids glycine, arginine, and methionine. The kidneys use glycine and arginine to make guanidinoacetate, which the liver methylates to form creatine , which is transported to the muscle cells for storage. It is also stored in the kidneys, sperm cells, and brain tissue .
As the name implies, the muscle power objective can be pursued if you want to achieve maximum size in your muscles or if you want them to be explosively strong (i.e. very powerful for short bursts at a time). In order to develop muscles this way you'll want to use no more than 3 sets in which no more than 8 reps are used. Muscle size and power is often used for muscles that are prominently displayed on the human figure, such as the pectorals, or the biceps and triceps.