Muscle growth is more difficult to achieve in older adults than younger adults because of biological aging, which leads to many metabolic changes detrimental to muscle growth; for instance, by diminishing growth hormone and testosterone levels. Some recent clinical studies have shown that low-dose HGH treatment for adults with HGH deficiency changes the body composition by increasing muscle mass, decreasing fat mass, increasing bone density and muscle strength, improves cardiovascular parameters, and affects the quality of life without significant side effects.[45][46][unreliable medical source?][47]
Nutrient timing is a hot topic, especially for athletes and anyone looking for that extra edge in the gym or in body transformation. Part of this stems from science showing that the timing of carbohydrate consumption does influence important aspects, such as glycogen replenishment (and in limited cases, muscle protein synthesis). The other side is practical: You want the most bang for your buck when it comes to the nutritional products and supplements you purchase.
Several studies have used either beet root juice or pomegranate extract in multi-ingredient performance supplements and have observed improvements in strength, hypertrophy, and performance in resistance-trained men. At this point, however, it's difficult to determine if these benefits are from beet root juice and pomegranate extract working alone or synergistically with other ingredients.[11,12]

In vitro studies on endothelial cells have noted that the benefits of creatine against atherosclerosis (via immune cell adhesion to the endothelial cell) are blocked with the pharmaceutical ZM241385, a high affintiy adenosine A2A receptor antagonist.[316] This particular receptor subset (A2A rather than other adenosine receptors) and its inhibition are similar to caffeine,[589] suggesting that caffeine may have an inhibitory effect on this mechanism of creatine.
Anti-depressive effects have been noted in woman with major depressive disorder when 5g of creatine monohydrate was supplemented daily for 8 weeks in combination with an SSRI. Benefits were seen at week two and were maintained until the end of the 8-week trial.[253] The improvement in depressive symptoms was associated with significantly increased prefrontal cortex levels of N-acetylaspartate, a marker of neuronal integrity,[254] and rich club connections, which refers to the ability of nerons to make connections to one another.[255] 

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.