That testosterone decreases with age has been clearly established by many studies over many years in several different populations of men (Harman et al 2001; Feldman et al 2002; Araujo et al 2004; Kaufman and Vermeulen 2005). Of even greater significance is the steeper fall of the most biologically active fraction of total testosterone, non-sex hormone binding globulin (SHBG)- bound testosterone, or bioavailable testosterone (bio-T). The classical, but not the only approach to measuring bio-T, is to precipitate out SHBG (and hence the testosterone which is strongly bound to it as well) and measure the remainder as total testosterone (Tremblay 2003). Vermeulen et al (1999) have devised a less tedious and less expensive method of measuring a surrogate for bio-T, namely calculated bio-T, inserting total T, albumin, SHBG and a constant into a mathematical formulation. There is a strong correlation between actual bio-T and calculated bio-T (Emadi-Konjin et al 2003).
I’m afraid I have no super cool “secrets” to share and there are no easy shortcuts to increasing your T. If you were expecting some magical potion or supplement or weird body hack that will instantly and naturally increase your T levels, what follows is bound to disappoint. Despite what some companies or websites might tell you, there’s no single thing that will boost your testosterone naturally for the long term.
There is increasing interest in the group of patients who fail to respond to treatment with PDE-5 inhibitors and have low serum testosterone levels. Evidence from placebo-controlled trials in this group of men shows that testosterone treatment added to PDE-5 inhibitors improves erectile function compared to PDE-5 inhibitors alone (Aversa et al 2003; Shabsigh et al 2004).
Since then there have been many publications documenting suppressed testosterone and gonadotropins (Daniell 2006) in men using opioid medications whether these agents were administrated orally (Daniell 2002) or intrathecally (Finch et al 2000). Not only do opioids act centrally by suppressing GnRH, they also act directly on the testes inhibiting the release of testosterone by Leydig cells during stimulation with human chorionic gonadotropin (Purohit et al 1978). Although the large majority of men (and women) receiving opioids do develop hypogonadism, about 15 percent also develop central hypocorticism and 15 percent develop growth hormone deficiency (Abs et al 2000).
Keep in mind that you can use virtually any type of equipment you want for this – an elliptical machine, a treadmill, swimming, even sprinting outdoors (although you will need to do this very carefully to avoid injury) -- as long as you're pushing yourself as hard as you can for 30 seconds. But do be sure to stretch properly and start slowly to avoid injury. Start with two or three repetitions and work your way up, don't expect to do all eight repetitions the first time you try this, especially if you are out of shape.

Natural remedies for treating erectile dysfunction Erectile dysfunction has many causes, can affect any male, and is often distressing? Some people advocate several different natural remedies, mostly herbs and other plants. Here, we look at their merits and side effects, plus lifestyle changes, and alternative therapies that may bring relief for erectile dysfunction. Read now