Testosterone is a key hormone involved in many body functions like building muscles, boosting strength, helping with sexual health, and making sure we feel good overall. People who have low levels of testosterone might think about getting testosterone replacement therapy (TRT) to help them feel better. But figuring out the best testosterone dose to use can be tricky because it depends on things like how old you are, what your health is like, how your diet and exercise program are,  and how your body reacts to the treatment.

In this piece, we're going to take a closer look at an important study led by Dr. Bhasin and his colleagues in 2001, which they shared with the world through the American Journal of Physiology and Endocrinology Metabolism. Their research was focused on understanding how various amounts of testosterone affect young men and figuring out the best dose for different results. By diving into what they discovered, we can learn a lot about finding just the right amount of testosterone for goals like getting stronger or building muscle.

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What is the optimal Testosterone Dose? Results from a Study

 

The Study Overview

In the research, about 65 young guys around 25 years old and in pretty good shape were studied. At first, the scientists stopped their bodies from making testosterone naturally by giving them a drug that blocks testosterone. Then, for 20 weeks, they gave these men shots of a type of testosterone called cypionate once every week. The amount given varied from as little as 25 milligrams to as much as 600 milligrams each week. By doing this, the researchers could see how different amounts of testosterone affected various things.

Testosterone Dose and Hormone Levels

The study uncovered a crucial link between the amount of testosterone given and the levels of different hormones in the body. The scientists looked at several hormones like total testosterone, free testosterone, LH (which stands for luteinizing hormone), SHBG (short for sex hormone-binding globulin), and IGF-1, also known as insulin-like growth factor 1. Here's what they found out:

  • The study showed that when the amount of testosterone given went up, so did the total testosterone levels in the body. In the beginning, people had testosterone levels between 500 and 600 ng/dL. By week 16, those who got higher doses (300–600 mg/week) saw their levels jump to between 1300 and 2300 ng/dL. Even with a smaller dose of just 125 mg/week, participants reached levels near what they started with. This hints that taking about 100 to 125 mg/week might be enough for young men to get their testosterone back to normal.
  • Regarding free testosterone: Just like with total testosterone, as more was administered, free testosterone amounts rose too. This backs up the idea that getting more dosage increases how much free testosterones there is available in someone's system.
  • When it comes to LH and SHBG, the more testosterone you take, the lower these levels go. As people up their dose of testosterone, they see a drop in LH and also in SHBG. This shows us that taking more testosterone can actually slow down how much LH is made and cut down on SHBG. By doing this, there's more free testosterone available for your body to use.

The impact of the testosterone dosage for muscle growth and body composition

The research looked into how different amounts of testosterone affect muscle size and the makeup of the body. By using a range of methods to measure, they checked out participants' lean muscle mass, known as fat-free mass, and their amount of body fat. Here's what was discovered:

  • When looking at fat-free mass, the research found that taking between 100 and 125 mg of testosterone every week helped people gain more muscle without fat. Those who took these amounts saw less body fat and more muscle. Taking even more (300–600 mg/week) led to better results in gaining muscle without fat. But, the smallest doses (25–50 mg/week) didn't really do much; sometimes they even made people put on more fat.
  • Regarding body fat, it turns out that higher doses of testosterone help reduce it. People who got between 100 and 125 mg each week lost some body fat. On the other hand, very low doses (25–50 mg/week) didn't help lose weight or might have caused a gain in body fatsuggesting high levels of this hormone can make you leaner by cutting down on fatty tissues while boosting your muscles' growth.

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Testosterone Dose Effect on Sexual Function and Libido

The study also looked into how different amounts of testosterone affect sexual function and desire. To figure this out, they asked participants to fill out questionnaires about their sex lives and how much they wanted sex. Here's what was discovered:

  • Regarding sexual activity, the research didn't show a big change in how often people were sexually active when they took more testosterone. The frequency of sexual encounters stayed pretty much the same across various doses. It's worth mentioning that there weren't a lot of participants in this study, which might have affected these findings.
  • On the topic of libido, it was found that taking 300–600 mg/week of testosterone led to a slight boost in desire. Yet, smaller doses ranging from 25–125 mg/week didn’t really make any difference in increasing libido. This suggests that higher amounts typically used by bodybuilders could be more effective at enhancing sexual desire.

No Changes in Cognitive Function

In the study, they also looked at how well people could think and remember things. But, even with different amounts of testosterone, there wasn't a big change in these brain skills. It's worth mentioning that this research was all about young guys. To understand if testosterone impacts thinking and memory in older folks, more studies need to be done.

Testosterone Dose Effect on Strength and Power

In the research, they looked at how strong and powerful participants' legs got by testing their leg press strength and power over 20 weeks. What they found was pretty interesting - the amount of testosterone given to participants made a real difference in how much stronger or more powerful their legs became. Those who got between 300–600 mg/week saw a noticeable boost in both strength and power of their legs. This hints that taking higher doses of testosterone could actually make people stronger and more powerful, even if they don't work out regularly.

Impact on Hemoglobin, Hematocrit, and Cholesterol Levels

Giving testosterone is known to change blood counts and fat levels in the body. The results of the study matched what we already know about this:

  • Hemoglobin: With the increase in testosterone dose, there was also a rise in hemoglobin levels. This means that as more testosterone is given, the amount of hemoglobin goes up too. It shows us that treatment with testosterone can affect erythropoiesis, which is how our body makes red blood cells.
  • Just like hemoglobin, when the doses of testosterone go up, so do hematocrit levels. Hematocrit is all about how much space red blood cells take up in our blood. The study didn't pinpoint what the best level of hematocrit should be, but it's important to mention that having too much can actually be risky for your heart health.
  • Lipid Profile: When testosterone was given, it turned out there's a kind of see-saw effect with HDL cholesterol, which is the good type. The more testosterone you have in your system, the lower your HDL cholesterol seems to go. This highlights why it's really important to keep an eye on lipid profiles if you're undergoing testosterone therapy.

 

Conclusion

In 2001, Dr. Bhasin and his team conducted a study that sheds light on how different amounts of testosterone can impact several factors. Despite focusing on young men and using a small group of participants, the research provides valuable information about how testosterone levels relate to muscle size, sexual health, brain function, physical strength, and blood-related measures.

According to the research, taking a dose of 100 to 125 mg per week might be enough for young men to get their testosterone levels back to normal. When it comes to bodybuilding, using higher doses like between 300 and 600 mg every week seems to really boost muscle size, strength, and sex drive. But it's important we remember that how people react can differ from one person to another. So, any treatment with testosterone should be customized for each person's unique needs and always checked on by a healthcare expert who knows what they're doing.

It's important to note that the research we're talking about happened more than 20 years ago. Since then, there might have been new findings. For those thinking about testosterone therapy, it's crucial to talk with medical experts. They can look into your unique situation and give advice just for you.

The study really helps us get a better grip on how testosterone dosing works and points out that we need to dig deeper into this topic. By doing more research, we can make the most of testosterone therapy's advantages while keeping any downsides to a minimum.

Getting a budget-friendly testosterone test without having to see a doctor is possible.

By purchasing a testosterone test from DiscountedLabs.com, you can discover your testosterone blood level and adjust your TRT dose accordingly.

 

Frequently Asked Questions

Is 2 ml of testosterone a week enough to build muscle?

The study reviewed above found that using 125 mg per week of injectable testosterone was enough to increase muscle.  Two mls of testosterone represent 400 mg/week, which will increase muscle but may cause side effects like high hematocrit, water retention, and blood pressure.

How much test cypionate per week for bodybuilding?

The study mentioned in this article concluded that 125 mg/week of test cypionate is enough to significantly increase muscle in bodybuilding without having significant TRT side effects.

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