Testosterone is significantly correlated with aggression and competitive behaviour and is directly facilitated by the latter. There are two theories on the role of testosterone in aggression and competition.  The first one is the challenge hypothesis which states that testosterone would increase during puberty thus facilitating reproductive and competitive behaviour which would include aggression.  Thus it is the challenge of competition among males of the species that facilitates aggression and violence.  Studies conducted have found direct correlation between testosterone and dominance especially among the most violent criminals in prison who had the highest testosterone levels.  The same research also found fathers (those outside competitive environments) had the lowest testosterone levels compared to other males. 
Phase 3: REST! By far everyone’s favorite period of the HCG diet plan (and honestly one of the most critical as well). Caloric intake is returned to between 1200-1500/day, but the low fat and no milk portions of the diet remain to keep the body free of external unnatural hormones. This phase is initiated after about 43-60 days dependent upon the regimen followed. During this particular phase, HCG intake is halted, and a new diet plan called the “stability phase” is activated. HCG must be flushed from the body for a period no shorter than 23 days, before beginning a new regimen. This is necessary for your body to keep shedding weight and not simply adapt to the HCG intake, either from HCG drops or otherwise. Maintenance is another term often used for Phase 3, but it really doesn’t matter what it is called, Phase 3 is probably the most critical phase for people who are interested in losing over 30 lbs, since multiple HCG regimens are necessary. There are specific phase 3 foods that go well with it, but just avoid dairy and high fat foods and you will do well in this phase and be ready to start again. Some people actually continue to lose weight during Phase 3! Not surprisingly they come back into their HCG diet plan after 23 days even happier than when they left!
Estrogen versus estrogen-progesterone combinations: Women who have not had a hysterectomy need to take progesterone in combination with estrogen to protect against uterine cancer.
Continuous versus cyclic therapy: For women who have not had a hysterectomy, the traditional way of prescribing HRT simulates the normal monthly cycling of hormones in the body. A woman on cyclic therapy receives estrogen alone for about 15 days, then estrogen plus progesterone for 10 days, and then nothing for 5 days each month. This usually results in regular menstrual bleeding six or more days after starting the progesterone-containing agent. Bleeding can be moderately heavy at first, but periods usually become light within six months.
An alternative method of taking HRT is to take estrogen and low-dose progesterone every day. Women who choose this regimen will generally not experience regular menstrual periods but will often have irregular, light spotting.
Women who have only recently entered menopause are likely to experience excessive, unpredictable bleeding if they take a continuous regimen. Therefore, women whose periods have stopped within the past six months may benefit from a cyclic regimen for six to twelve months.