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 [2]. 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 [1], which is transported to the muscle cells for storage. It is also stored in the kidneys, sperm cells, and brain tissue [5].
What kind of exercises? Work all major muscle groups, starting with the larger muscles. Always include exercises for opposing muscles: for example, work the biceps and triceps of your arms, and the quadriceps and hamstrings of your thighs. Avoid above-the-shoulder exercises if you have arthritis in your upper body, and talk to your doctor before using leg press machines if you have arthritis in your knees or hips.
Using too much weight, too soon; always start lower than your expected ability and work your way up that first workout. If your form suffers, you are swinging the weight, or using momentum, this indicates you may be using too much weight. Greater momentum increases the potential for injury and reduces the effectiveness to the muscle group being targeted.