There are pills in the United States for testosterone supplementation, but their use is strongly discouraged because they cause significant liver toxicity. A safe oral formulation called testosterone undecanoate is available in Canada and in Europe, but not in the United States. What’s quite exciting is that an injectable version of testosterone undecanoate (Nebido) was submitted to the FDA for approval in August 2007. (It’s already approved in many other countries.) It lasts for 12 weeks, so a patient could come in and get a shot about four times a year. [Editor’s note: In December 2009, the brand name of the drug in the United States was changed to Aveed. As of January 2011, it was still awaiting FDA approval.]
Epidemiological evidence supports a link between testosterone and glucose metabolism. Studies in non-diabetic men have found an inverse correlation of total or free testosterone with glucose and insulin levels (Simon et al 1992; Haffner et al 1994) and studies show lower testosterone levels in patients with the metabolic syndrome (Laaksonen et al 2003; Muller et al 2005; Kupelian et al 2006) or diabetes (Barrett-Connor 1992; Andersson et al 1994; Rhoden et al 2005). A study of patients with type 2 diabetes using measurement of serum free testosterone by the gold standard method of equilibrium dialysis, found a 33% prevalence of biochemical hypogonadism (Dhindsa et al 2004). The Barnsley study demonstrated a high prevalence of clinical and biochemical hypogonadism with 19% having total testosterone levels below 8 nmol/l and a further 25% between 8–12 nmol/l (Kapoor, Aldred et al 2007). There are also a number longitudinal studies linking low serum testosterone levels to the future development of the metabolic syndrome (Laaksonen et al 2004) or type 2 diabetes (Haffner et al 1996; Tibblin et al 1996; Stellato et al 2000; Oh et al 2002; Laaksonen et al 2004), indicating a possible role of hypogonadism in the pathogenesis of type 2 diabetes in men. Alternatively, it has been postulated that obesity may be the common link between low testosterone levels and insulin resistance, diabetes and cardiovascular disease (Phillips et al 2003; Kapoor et al 2005). With regard to this hypothesis, study findings vary as to whether the association of testosterone with diabetes occurs independently of obesity (Haffner et al 1996; Laaksonen et al 2003; Rhoden et al 2005).
^ Jump up to: a b Sapienza P, Zingales L, Maestripieri D (September 2009). "Gender differences in financial risk aversion and career choices are affected by testosterone". Proceedings of the National Academy of Sciences of the United States of America. 106 (36): 15268–73. Bibcode:2009PNAS..10615268S. doi:10.1073/pnas.0907352106. PMC 2741240. PMID 19706398.
Transdermal preparations of testosterone utilize the fact that the skin readily absorbs steroid hormones. Initial transdermal preparations took the form of scrotal patches with testosterone loaded on to a membranous patch. Absorption from the scrotal skin was particularly good and physiological levels of testosterone with diurnal variation were reliably attained. The scrotal patches are now rarely used because they require regular shaving or clipping of scrotal hair and because they produce rather high levels of dihydrotestosterone compared to testosterone (Behre et al 1999). Subsequently, non-scrotal patches were developed but the absorptive capacity of non-scrotal skin is much lower, so these patches contain additional chemicals which enhance absorption. The non-scrotal skin patches produce physiological testosterone levels without supraphysiological dihydrotestosterone levels. Unfortunately, the patches produce a high rate of local skin reactions often leading to discontinuation (Parker and Armitage 1999). In the last few years, transdermal testosterone gel preparations have become available. These require daily application by patients and produce steady state physiological testosterone levels within a few days in most patients (Swerdloff et al 2000; Steidle et al 2003). The advantages compared with testosterone patches include invisibility, reduced skin irritation and the ability to adjust dosage, but concerns about transfer to women and children on close skin contact necessitate showering after application or coverage with clothes.
Consuming high amounts of sugary foods raises your blood glucose levels, which causes your body to release insulin as a response to the raised blood glucose levels. If not managed correctly, the body begins to develop a tolerance to insulin and cannot absorb the sugars in the blood stream as it used to, causing you to become insulin resistant. Being insulin resistant releases cortisol, and as you know, cortisol has extremely negative effects, lowering testosterone by quite a bit.
Ten healthy men aged around 24 years old spent 1 week sleeping for 8 hours per night at home, they then spent the next 11 nights in a lab. They slept for 10 hours per night for 3 nights, followed by 8 nights of restricted sleep, when they slept for only 5 hours. Doctors checked their blood every 15 to 30 minutes during the last night that they slept 10 hours, as well as on the sleep-restricted session.
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In both men and women, imbalances in testosterone result in health issues like diabetes, obesity, metabolic syndrome, and osteoporosis. So testosterone is important for more than just men’s health issues; it crosses gender boundaries and affects all areas of the body. The Providers at New Leaf Wellness are aware of the risks and inconveniences that imbalanced hormone levels bring to the human body, and we are pleased to offer Natural Hormone Therapy to our clients.
Actually he knows exactly what he is talking about. The fact your a doctor gives zero confidence that you have any knowledge in HRT, in fact I believe it where you wonderful doctors that started the larger opioid epedemic the world has ever seen. Make sure if your considering HRT you see a doctor that specializes in it, otherwise you very well could be getting terrible advice by a doctor with no knowledge of the subject as is the case here. Do your research on the doctor, and make sure you are getting a doctor that specializes in HRT. Don’t forget somebody had to finish at the bottom of the class in med school, and based on this doctors comments he probably was one of them. Doctors can be as dangerous as they are helpful; as we have seen quite clearly with the opioid epidemic being experienced in this country, as I mentioned above. This epidemic was caused 100% by doctors in this country. I own several HRT clinics and employ some of the top doctors in the HRT field. Our doctors put our patients health above all else especially above the all mighty dollar. I assure you the comment by this Dr. claiming the post above makes absolutely no sense (I believe it makes no sense to him, because he has zero knowledge on the subject) is dead wrong, and the poster was pretty much right on point with what he said.
Magnesium: About 60% of our (if you’re a man) testosterone is bound to Sex Hormone Binding Globulin (SHBG), which removes the anabolism of testosterone and the availability thereof, robbing the rest of the body from any testosterone. What magnesium does is it lowers the SHBG count by quite a bit, granting the free testosterone in the body to increase in a large amount.
Testosterone increases the tolerance for risk-taking. Testosterone has a strong link with one’s willingness to take risks. Studies show that men with low levels of power and status, but high levels of T, are motivated to take risks in order to gain status and power. On the other hand, men with high T, who already have power and status, are more risk-averse, because they want to hold on to what they have.
Epidemiological studies suggest that many significant clinical findings and important disease states are linked to low testosterone levels. These include osteoporosis (Campion and Maricic 2003), Alzheimer’s disease (Moffat et al 2004), frailty, obesity (Svartberg, von Muhlen, Sundsfjord et al 2004), diabetes (Barrett-Connor 1992), hypercholesterolemia (Haffner et al 1993; Van Pottelbergh et al 2003), hypertension (Phillips et al 1993), cardiac failure (Tappler and Katz 1979; Kontoleon et al 2003) and ischemic heart disease (Barrett-Connor and Khaw 1988). The extent to which testosterone deficiency is involved in the pathogenesis of these conditions, or to which testosterone supplementation could be useful in their treatment is an area of great interest with many unanswered questions.
In this study, an ethical approval No. 20171008 was obtained from Ethical Committee of Qassim province, Ministry of Health, Saudi Arabia. At the beginning, a written informed consent was taken from a 30-year-old man for participation in this study. The patient came to the King Saud Hospital, Unaizah, Qassim, Saudi Arabia, with abdominal pain. He looked pale and hazy, hence, immediately admitted. A battery of lab tests was ordered by the attending physician. Moreover, abdominal ultrasound imaging was performed. The results of the tests showed high levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), indicating liver injury. Other serum parameters, such as total proteins, albumin, and iron, in addition to the levels of kidney and heart enzymes were all found to be in the normal range. A complete blood count showed normal levels of red blood cells, white blood cells, and platelets. The ultrasound images of the man’s abdomen were all found to be normal as well [Figure 2]. The patient, a sportsman, described that he was taking a testosterone commercial booster product called the Universal Nutrition Animal Stak for the purpose of enhancing his testosterone profile to achieve a better performance and body composition. The attending physician decided to admit the man for 1 week. Some medications were prescribed, and the patient was discharged later after having fully recovered.
Another study in 2015 by Melville and friends gave subjects either three or six grams of DAA per day for a 14 days (2 weeks). Researchers noted that the 3g dose of D-aspartic acid did not result in any meaningful changes in testosterone levels (or any other anabolic hormones for that matter). However, the group of men receiving 6g per day experienced a significant reduction in both total testosterone and free testosterone levels, with no concurrent change in other hormones tested.
Note that DHT is what causes male pattern baldness so it stands to reason that fenugreek may delay the balding process. A quick Google search of “fenugreek and baldness” reveals that I am not the only genius struck with this idea. There are sites out there that claim that a fenugreek+saw palmetto concoction or applying a fenugreek paste can help prevent Mr. Cleanitis.
Felt I was more sluggish than I should be,Went on TRT ’cause my bloodwork said I fell in the parameters for hormone therapy. When i started felt I was 17, (I was 50))I did everything possible and passed for type A, and physiologically, things seem to heal faster. But I missed memories, now that I was speeded-up I no longer could easily connect and be a part of them.
Some foods, vitamins, and herbs can help boost your testosterone levels. Be sure to talk to your doctor, if you’re concerned about low testosterone. These alternative and natural treatments aren’t proven to be more, or as, effective as traditional testosterone therapy. Some may also interact with any medications you may be taking and cause unintended side effects.
Studies have shown that testosterone-replacement therapy may offer a wide range of benefits for men with hypogonadism, including improved libido, mood, cognition, muscle mass, bone density, and red blood cell production. But little consensus exists on what constitutes low testosterone, when testosterone supplementation makes sense, or what risks patients face. Much of the current debate focuses on the long-held belief that testosterone may stimulate prostate cancer.
The content here is for information purposes only. By delivering the information contained herein is does not mean preventing, diagnosing, mitigating, treating or curing any type of medical condition or disease. When beginning any natural supplementation regiment or integrative treatment, the advice of professionally licensed healthcare providers is advisable to seek.
Boron, a mineral, keeps the cell walls of plants strong. Eating dried fruits and nuts gives you abundant amounts of boron. You can also take boron supplements. It's important to keep your daily boron intake at less than 20 mg, however, according to a current factsheet available from the U.S. National Library of Medicine. High doses of boron can cause serious side effects such as skin inflammation and peeling, irritability, tremors or depression.
Men who produce more testosterone are more likely to engage in extramarital sex. Testosterone levels do not rely on physical presence of a partner; testosterone levels of men engaging in same-city and long-distance relationships are similar. Physical presence may be required for women who are in relationships for the testosterone–partner interaction, where same-city partnered women have lower testosterone levels than long-distance partnered women.
Every ingredient can be harmful when taken in significant quantities (we go more into that below), so we pored over each booster’s ingredient list to make sure that they weren’t serving up an overdose. In particular, we took a close look at magnesium and zinc, which have enough scientific background behind them to offer hard upper limits on how much you can safely consume.
For this reason, after the 2008 financial market meltdown, some commentators put the blame for the crash on the male-dominated profession, arguing that men take too many risks, and the economy would do better and be more stable if it was run by women. Of course, risk-taking does come with inherent risk, but it has also been responsible for the lion’s share of society’s progress and innovation since the dawn of time. Financial markets would likely not exist – period – without testosterone-driven risk-taking.
The International Journal of Sports Physiology and Performance recently studied tennis players, rugby teams, and wrestlers to find a link between testosterone and competitive outcome. They found that the difference between winning and losing was reflected in testosterone levels! The athletes' own natural testosterone prior to the game was directly related to the outcome after the game -- the higher the testosterone, the more frequently the athlete won.6
AC, I just ran across the thread… definitely start the injections. Should help with levels that low. I’m 36 and have battled low T for 6-7 years. My labs came back to show 90ng/dl when I just turned 30, and I’ve done Testosterone cypionate injections @ 100mg/mL weekly, Testim, Androgel, and Fortesta over the years. I’m actually going to my endocrinologist tomorrow to have new blood work done.
High levels of testosterone in the bloodstream lead to increased energy and aggressiveness. The latter pertains to one’s sense of motivation to train harder to achieve optimum muscle growth. Increased aggressiveness or motivation during a workout due to the intake of testosterone boosters guarantees faster progress to beginners as well as professional athletes and bodybuilders.
Take 1 teaspoon. Incredibly dense in nutrients and feed by bees to the larvae who grows on to be the queen bee. I found one human study where a 4g daily serving led to an small increase in testosterone in older men (ref 78). There are also numerous animal studies (ref 79) showing positive effects. Personally I source NZ manuka royal jelly from Manuka Health.
A notable study out of Wayne State University in Indiana found that older men who had a mild zinc deficiency significantly increased their testosterone from 8.3 to 16.0 nmol/L—a 93 percent increase—following six months of zinc supplementation. Researchers of the study concluded that zinc may play an important role in modulating serum testosterone levels in normal healthy men.6
In fact, studies on vegetarian and low-fat diets both show reduced testosterone levels of about 12 percent. Where higher fat diets of at least 40 percent of calories, with a higher intake of saturated fat, show increased testosterone levels. Why? It’s not rocket science. After all, cholesterol makes up the building blocks from which testosterone is formed; without it, the hormone simply can’t synthesize. Organic eggs are one of the best dietary sources. In addition to essential fatty acids, a whole egg is rich in aspartic acid, an amino acid that triggers production of testosterone.
Feeling low energy, lack of enthusiasm, but not so much on the sexual side, seems okay. At age 63 started an exercise program. nothing seem to help bring me back, so had my blood test at age 64. 150. 6 months later 165. My doctor started me on testosterone patches after a heart and prostate exam. Now two months into program, now using the gel, there seems little change. Disappointed. I am guess my next blood test will show less than 200. I am disappointed sufficiently to decide not to continue the program. I mean, the drugs cost $500 a month, although my cost is less. I guess my question is if I quit the program, will my body return to its normal, or will it be worse. i can live with a low normal, but less would not not be acceptable.
Garlic is a very effective food that has been used for centuries in treating various physical ailments including heart problems and respiratory infections. What most people don’t know is that it is also a potent aphrodisiac and very effective in boosting sperm volume. It contains a compound called allicin which improves blood flow to the male sexual organs, increasing sperm production and semen volume.
The study population in these TTrials included men aged 65 years or older with mean morning serum testosterone concentrations of 275 ng/dL or less and symptoms of impaired sexual function, physical function, or vitality. These trials were placebo-controlled and the testosterone treatment group received 1% testosterone gel at variable doses adjusted to maintain plasma testosterone at levels normal for young men (500-800 ng/dL).
Short bursts of timed intense activity — known as high-intensity interval training or HIIT — trigger the body to make more testosterone than less-than-intense aerobic or endurance exercise, says La Puma. Spurts of activity stimulate androgen-sensitive tissue, he explains, which tells the body to make more testosterone. Strength training has also been shown to increase testosterone.
A couple years ago I was having a problem with my thighs burning when walking up stairs. I noticed the muscles in my legs looking smaller. So I had my doc to check my T levels , and it was under 100. So she started me on testosterone injections weekly 200mg . After several injections I felt great , muscles in legs came back , lots of energy everything good . Leveled out at 3 injections a week 100mg , had a T level of 550 . So I go in for my scheduled injection and they tell me there out of testosterone . I might mention, this is a health care facilility that gives financial assistant if needed. And they have 3 or doctors and a nurse practitioner, which was who I was seeing . So I went on to check back often and got the same reply , were out of supply . So finally after months of the same , I gave up . I started loosing wait and my nerves got bad . Was having panic attacks etc. but I was coming off Prozac at the same time so I blamed it all on that. I was so bad with my nerves I ended up in the ER while on vacation . Doc there put me on a med for stress which I’m still using . After close to a year I checked back with the place I was getting TRT and they were resupplyed with testosterone. So I started back up because of low sex drive and ED. My first injection of 200mg was just short of a Marical , nerves felt great ED gone , had a sex drive , lot of energy . Then after 7 days or so all gone bad nerves started back up . He had me scheduled for anouther injection in 4 weeks 100mg . I went in for injection and after a couple days started feeling a little better . Then same thing as before about 7 days later nerves and everything else as before got worse . 3 weeks later I finally got a appt. with this different doc then I use to have . Told him the problems I was having , which included a horrible down mood , no energy . He decided to start injections every 2 weeks and upped the dose slitley. It’s been 5 days and already noticing ED problem reaccuring . He’s worried about the threat of prostate cancer. And doesn’t want to add any more injection to the schedule. I guess I’m going to have to start seeing the nurse practitioner who seemed to be more liberal and informed about TRT. I feel once a week injection is what it will take to get feeling good again. I’m 57 now with good health . Just need to get my T level on track with a doctor that will listen to how his patient is feeling . My last T level was at 365 . I failed to mention before I started the injections I was on androgel Dailey , 5 pumps a day . Then he gave me the injection of 200mg test . That’s when I felt fantastic for about a week or so . Then down hill . And I wanted to switch because the injection just seem so much better and they are . I noticed a big difference.
Bisphenol-A also known under the name of BPA is a chemical compound which is very widespread for manufacturing a wide spectrum of plastic items and aluminum cans. Many studies have already proven the fact that even the smallest amount of BPA is very harmful to the human health. This compound causes hormonal imbalance and even may lead to prostate cancer.
Ryan is a former college wrestler and lifelong fitness fanatic. He has run half marathons, done mud runs, placed in body transformation contests, coached wrestling and now coaches girls soccer. Not to mention he has also tried literally hundreds of supplements over the years and has a vast and thorough supplement knowledge. He is also the owner of this website. Feel free connect with him on his LinkedIn page below.
DHEA (dehydroepiandrosterone) extract - this is a chemical that used in your body which a ‘hormone precursor’. This means it’s the chemical used by the body to create hormones like oestrogen or testosterone. When taken as supplement it is believed to boost testosterone levels, but DHEA has not been shown to increase testosterone in men. DHEA comes in two form:
I am a 67 yo male diagnosed with prostate cancer gleason 6. I have a prescription on bicalutamide 50 mg a day since Nov 2016 and leuprolide 11,5 mg every 3 months. My testicles reduced their size to half it´s original size, my libido is almost zero. I went through a radiotherapy of 45 sessions; my PSA level went from 11.2 to 0.13 on my last test from Sept 2017 and the leuprolide injections are taken away from my prescription by my urologist. I am planning to take TRT with Testosterone mix called SUSTANON 250 mg per week and HCG 5000 IUs twice a month. Give me your thoughts please
Remember that each person is unique, and each body responds differently to treatment. TT may help erectile function, low sex drive, bone marrow density, anemia, lean body mass, and/or symptoms of depression. However, there is no strong evidence that TT will help memory recall, measures of diabetes, energy, tiredness, lipid profiles, or quality of life.
The IOM report estimated that a study of whether there is an increased risk of prostate cancer in men on testosterone therapy might require following 5,000 men for three to five years. Before launching such an endeavor, the report recommended more firmly establishing the effectiveness of testosterone-replacement therapy, saying that studies of long-term risks and benefits should be conducted only after short-term efficacy has been proven. That means the male equivalent of the WHI remains far off.
While steroids like DHEA can be used to boost testosterone, if used in the wrong dosages or by people who don’t need them they can raise T-levels far beyond the normal range, which is what causes accelerated muscle gain. According to Dr. Emil Hodzovic, who is a competitive bodybuilder as well as a doctor with Medichecks, steroids come with “a set of risks, including liver damage, hormone imbalance, high blood pressure, and a higher risk of a stroke or heart attack”.
It’s worth emphasizing that these supplements are totally legit. They’re NOT steroids. Meaning, only the natural and harmless ingredients have been used to make these products, which can help the guys dealing with the low testosterone problems, such as low energy, fatigue, muscle loss, irritability, and similar. Usually, the guys tend to start experience these problems in their late 20s and in some cases in their early 30s.
Preliminary research has shown that clomiphene citrate (Clomid), a drug generally prescribed to stimulate ovulation in women struggling with infertility, can foster the production of natural testosterone, termed endogenous testosterone, in men. In a recent prospective study, 36 hypogonadal men took a daily dose of clomiphene citrate for at least three months. Within four to six weeks, all of the men had heightened levels of testosterone; none reported any side effects during the year they were followed.
Based on my research, I guess fenugreek is kind of a crapshoot, a toss-up, a gamble, a coin toss, a roulette spin of sorts, you get the idea. There are a lot of conflicting reports on whether it increases or decreases testosterone levels, but it seems like the libido-improvement is consistent. The vast majority of men report positive effects from fenugreek so go ahead and give it a shot.
A testicular action was linked to circulating blood fractions – now understood to be a family of androgenic hormones – in the early work on castration and testicular transplantation in fowl by Arnold Adolph Berthold (1803–1861). Research on the action of testosterone received a brief boost in 1889, when the Harvard professor Charles-Édouard Brown-Séquard (1817–1894), then in Paris, self-injected subcutaneously a "rejuvenating elixir" consisting of an extract of dog and guinea pig testicle. He reported in The Lancet that his vigor and feeling of well-being were markedly restored but the effects were transient, and Brown-Séquard's hopes for the compound were dashed. Suffering the ridicule of his colleagues, he abandoned his work on the mechanisms and effects of androgens in human beings.
According to a study in the International Journal of Reproductive BioMedicine, D-Aspartic acid increases testosterone levels in some animals. However, studies that have looked at its effects on humans are inconclusive and mainly of poor quality. The paper says there is an urgent need for more research on this chemical, which occurs naturally in some human tissues.
Think: when you were teenager: you were active without thinking of ways to be active. When you start TRT, you want to be mobile/active (maybe again), don’t forget this when you stop TRT. You have to think of ways to incorporate activity into your routine or you get porky.When you cycled, walked everywhere as a teen you did this automatically. Without the hormone stimulus you must use your head and memories of what to do. here’s where the memory issue occurs.
But if somebody fails testosterone therapy, meaning that their erections aren’t any better, I’ve said, “Well, let’s stop the testosterone and try one of the PDE5, or phosphodiesterase type 5, inhibitors — sildenafil (Viagra), tadalafil (Cialis), and vardenafil (Levitra).” A lot of patients then say, “Well, actually, I’d like to stay on the testosterone. True, it’s not helping my erections, but I’m more turned on, and I’m getting these other benefits.” So we often continue the testosterone and add a PDE5 inhibitor.
6) Take Cold Showers: Cold showers have been known to stimulate and boost testosterone production and improve metabolism, detoxification and brain function. Start your shower with warm/hot water and turn it to cold for the last 30-60 seconds while pumping your muscles and creating a big shiver as your muscles contract. That will help to boost internal heat and boost testosterone production. This article will help you.
A related issue is the potential use of testosterone as a coronary vasodilator and anti-anginal agent. Testosterone has been shown to act as a vasodilator of coronary arteries at physiological concentrations during angiography (Webb, McNeill et al 1999). Furthermore men given a testosterone injection prior to exercise testing showed improved performance, as assessed by ST changes compared to placebo (Rosano et al 1999; Webb, Adamson et al 1999). Administration of one to three months of testosterone treatment has also been shown to improve symptoms of angina and exercise test performance (Wu and Weng 1993; English et al 2000; Malkin, Pugh, Morris et al 2004). Longer term studies are underway. It is thought that testosterone improves angina due its vasodilatory action, which occurs independently of the androgen receptor, via blockade of L-type calcium channels at the cell membrane of the vascular smooth muscle in an action similar to the dihydropyridine calcium-channel blockers such as nifedipine (Hall et al 2006).
Why do we need magnesium? Magnesium is an essential nutrient in the body that can help decrease the risk of developing osteoporosis, improve insulin sensitivity, and lower the risk of hypertension. This article looks at other health benefits of magnesium, what happens if a person has a deficiency, supplements, and how to include it in the diet. Read now
A number of research groups have tried to further define the relationship of testosterone and body composition by artificial alteration of testosterone levels in eugonadal populations. Induction of a hypogonadal state in healthy men (Mauras et al 1998) or men with prostate cancer (Smith et al 2001) using a gonadotrophin-releasing-hormone (GnRH) analogue was shown to produce increases in fat mass and decreased fat free mass. Another experimental approach in healthy men featured suppression of endogenous testosterone production with a GnRH analogue, followed by treatment with different doses of weekly intramuscular testosterone esters for 20 weeks. Initially the experiments involved men aged 18–35 years (Bhasin et al 2001) but subsequently the study was repeated with a similar protocol in men aged 60–75 years (Bhasin et al 2005). The different doses given were shown to produce a range of serum concentrations from subphysiological to supraphysiological (Bhasin et al 2001). A given testosterone dose produced higher serum concentrations of testosterone in the older age group (Bhasin et al 2005). Subphysiological dosing of testosterone produced a gain in fat mass and loss of fat free mass during the study. There were sequential decreases in fat mass and increases in fat free mass with each increase of testosterone dose. These changes in body composition were seen in physiological and supraphysiological treatment doses. The trend was similar in younger versus older men but the gain of fat mass at the lowest testosterone dose was less prominent in older patients (Bhasin et al 2001; Bhasin et al 2005). With regard to muscle function, the investigators showed dose dependent increases in leg strength and power with testosterone treatment in young and older men but there was no improvement in fatigability (Storer et al 2003; Bhasin et al 2005).