If you want to improve your testosterone levels, you're not alone. As a gym-goer and fitness enthusiast, you know that testosterone is essential for building muscle and strength. While there are many products on the market that claim to boost testosterone, not all of them are effective. In this E-book, you will explore some of the most proven ways to increase your testosterone levels.
So, whether you're looking to improve your gym performance or feel more energetic overall, read on for some helpful tips!
What is Testosterone?
The essential male sex hormone, testosterone, is in charge of regulating male sexuality. The biological and psychological traits you'd identify with masculinity, such as significant muscular mass, strength, facial hair, libido, and sperm production, are produced mainly by this male hormone. The hormone also aids in the metabolism, cognitive functioning, some sleep issues, the prevention of cardiovascular disease, low bone density, and a number of other critical activities.
Since steroids make up most of the testosterone's chemical makeup, it is generally recognized that they have substantial physiological and psychological impacts on guys, especially adults. From the age of 30, some men's testosterone production starts to decline steadily. Other studies suggest that the typical age at which physiological levels begin to decline is about 40. The primary symptom of low testosterone in younger men is a lack of energy and exhaustion.
Men may also experience various physiological and psychological symptoms as they age, including a loss of sexual desire, erectile dysfunction, acute depression, weariness, poor energy levels, and sleeplessness as testosterone blood concentrations gradually fall.
The appeal of anabolic steroids is understandable given that higher testosterone levels have been demonstrated to promote muscular growth, greater neural system activation, increased power and strength, improved mood, increased libido, and numerous other advantages.
A favourable association was identified between testosterone-mediated reactions and both functional performance and body composition, consistent with previous research on the anabolic effect of testosterone and its impact on muscular strength in alterations brought on by training.
Why Do Testosterone Levels Matter?
Testosterone is a hormone that is produced by the body to help regulate a number of different functions. In men, testosterone levels play a role in sexual development and fertility. Testosterone levels also affect bone and muscle mass and red blood cell production.
Low testosterone levels can cause various different problems, including fatigue, low libido, and depression. In some cases, low testosterone levels can also lead to osteoporosis.
Testosterone levels can be affected by various factors, including age, diet, and exercise. Maintaining healthy testosterone levels is essential for overall health and well-being.
Now the question is, what is the normal testosterone level in men? It doesn't really have an answer. However, in studies of men aged 20 to 80 and all-male groups, the average testosterone levels are regarded as normal values. Although it may appear absurd, this is reasonably near to the truth. Men who are physically fit, obese, exercise, use drugs, or binge drink will all fall under this category, as will men who may be ill or under physical, emotional, or environmental stress.
The median average of the normal levels is established, and then you have normal testosterone levels. The top and bottom numbers are discarded when calculating normal testosterone levels.
- The NHS states that the range is 10–30 nmol/l.
- The values of the British Society of Sexual Medicine are listed down below:
- The typical indication for testosterone therapy is a Total Testosterone (TT) level of less than 8 nmol/l or a Free Testosterone (FT) level of less than 180 pmol/l (0.180 nmol/l; based on 2 independent values from 8 to 11 AM).
- No testosterone therapy is necessary if the TT or FT levels are greater than 12 nmol/l or 225 pmol/l (>0.225 nmol/l), respectively.
- Based on symptoms, testosterone therapy may need to be tried for a minimum of 6 months at levels between 8 and 12 nmol/l.
One of the top diagnostic businesses in the world, Labcorp, has altered its recommendations from 12-42 nmol/l (348-1197 ng/dL) to 9-32 nmol/l(264-916 ng/dl).
To make matters even more complicated, many endocrine organizations in Europe and the West have varying ideas about what constitutes low or appropriate amounts of testosterone. Doctors' perspectives on the value of testosterone in older men or the efficacy of testosterone therapy vary greatly.
Most people utilize the value of 8.64 nmol/l to 32 nmol/l for testosterone levels as the NHS uses it. Therefore, a male patient is regarded to have low testosterone and should be eligible for testosterone replacement therapy if his testosterone levels are below 8.64 mmol/l (TRT).
But what happens if the patient has levels of 9.5 nmol/l and experiences the typical signs of low testosterone? What is a physician's job? Nothing, usually. In that case, a doctor would soothe the patient and send him home if they followed the rules. They may also give out antidepressants.
Exercises and Lifting Weight to Boost Testosterone
Testosterone levels rise during some workouts. But how your testosterone levels are impacted depends on your biological sex and the type of exercise you perform. Also, not all exercises work in favour of increasing the testosterone level. This is how exercise and workout affect your testosterone levels:
- A study shows that testosterone levels in men and women who had lifted weights discovered that while testosterone levels in men significantly increased, those in women barely changed.
- Resistance training can briefly raise testosterone and affect how fat is distributed.
- Regular exercise improved testosterone and growth hormone (GH) levels in older men and positively impacted brain function.
- Dihydrotestosterone (DHT) levels rose by 14.5% in 102 men who hadn't exercised much before during a year.
- According to a 2012 study of men, exercising frequently was associated with greater testosterone levels than those who were sedentary (didn't exercise at all).
- According to a 2016 study of obese men, regular exercise increased testosterone levels more than combined diet and exercise.
Best Exercises to Boost Testosterone Level
As was already mentioned, not all forms of exercise have the same effects on testosterone levels. Resistance training and HIIT are the two main exercises beneficial for boosting testosterone.
Resistance training can help raise short and long-term testosterone levels. Weightlifting and other resistance training are the best exercises for short and long-term testosterone augmentation. It has been discovered to be very beneficial for those who have penises.
According to a study, men who engaged in strength/resistance training three days a week for four weeks experienced increased testosterone levels immediately following an exercise and over time.
However, not everyone experiences the same outcomes. One 30-minute weightlifting session mentioned earlier raised testosterone levels by 21.6 percent in men but only 16.7 percent in women.
Additionally, research implies that women's testosterone level increases only temporarily.
Another older study discovered that testosterone levels rose in both young and older males after three sets of 8 to 10 repetitions of weightlifting. However, other sex hormones, such as GH, spiked significantly more frequently in younger men than in older men.
High-Intensity Interval Training (HIIT) has become a famous workout routine for people looking to improve their cardiovascular health and lose weight. However, HIIT can also be an effective way to increase testosterone levels. HIIT can significantly increase testosterone levels, even in men who are not regularly active. Furthermore, HIIT can help improve your sleep quality, which is another critical factor in maintaining healthy testosterone levels. HIIT is a great option if you are looking for a workout that will not only help you lose weight but also improve your testosterone levels.
One study on males revealed that interval training, which consists of 90 seconds of vigorous treadmill jogging followed by 90 seconds of recovery, significantly raises free testosterone levels compared to just running for 45 minutes.
According to research, younger and older men's testosterone levels were raised by taking DHEA supplements and engaging in five sessions of 2-minute cycle activities. A study from 2014 discovered that HIIT raised men's testosterone levels.
Other Ways to Improve Testosterone Levels
Apart from exercise and workouts, other proven ways exist to improve testosterone levels. Getting enough sleep and managing stress levels are a few of the important things when it comes to maintaining hormone levels.
Getting 7-8 hours of sleep everynight and managing stress through relaxation techniques such as yoga or meditation can help to improve testosterone levels. Furthermore, eating a healthy diet is important for overall health and can help improve hormone production.
Foods rich in zinc, including oysters, beef, and pumpkin seeds, are particularly beneficial for boosting testosterone levels. By following these simple tips, it is possible to boost testosterone levels naturally.
Testosterone Boosting Foods
While testosterone levels naturally decline with age, several lifestyle factors, including poor diet, can contribute to low testosterone. Fortunately, some simple dietary changes can help to boost testosterone levels. Here are some of the best foods to eat for testosterone:
Vitamin D, zinc, and omega-3 fatty acids are among the minerals that are abundant in fatty fish like salmon and sardines and are crucial for hormonal health. Your general health, including hormonal health, is probably improved by having healthy fat sources in your diet, such as fatty fish.
Additionally, fatty fish are a fantastic source of protein, zinc, and vitamin D, which are essential for preserving normal testosterone levels.
For instance, research indicates that testosterone levels are often lower in males with low vitamin D levels compared to those with higher levels. It is because vitamin D is necessary for healthy male reproduction.
Healthy fat, like that found in avocados, is crucial for maintaining hormonal balance. Additionally, avocados contain magnesium and boron, which may raise testosterone levels.
A trace mineral called boron affects the body's testosterone metabolism and may prevent testosterone deterioration.
Although some research suggests that taking high boron supplements may help certain people's testosterone levels, the findings are conflicting. To fully comprehend how boron supplements affect testosterone, more research is required.
Adding boron-rich foods to your diet, like avocados, may help you maintain healthy testosterone levels even if it is not currently advised to take boron pills to raise testosterone.
Berries, Cherries, and Pomegranate
Flavonoid antioxidants are abundant in berries, cherries, and pomegranates and may help prevent damage to testosterone-producing cells and boost testosterone synthesis.
In a study, testosterone levels were shown to increase, and Leydig cells, which create testosterone, were protected from damage when rats were supplemented with pomegranate juice.
Before we can say for sure whether pomegranates or their juice can alter your testosterone levels, more research on humans is required.
Pomegranates, berries, and cherries may guard against inflammation brought on by obesity, which can cause testosterone levels to drop.
Consuming foods high in antioxidants like these fruits may improve general health, including hormonal health.
Magnesium, a mineral essential for maintaining optimum testosterone levels, especially in older men, is found in dark, leafy greens and is a great source of micronutrients.
Because magnesium lowers oxidative stress, it is believed to improve testosterone bioactivity in the body. An imbalance between the body's antioxidant defences and free radicals results in oxidative stress.
Incorporating foods that fight oxidative stress may help maintain healthy testosterone levels because oxidative stress and inflammation can lower testosterone.
An earlier investigation with 399 males aged 65 or older discovered that those with higher blood magnesium levels also had higher testosterone levels than those with lower ones.
In addition, a study on Taiwanese men discovered a relationship between poor consumption of leafy green vegetables and decreased testosterone levels.
Therefore, increasing your intake of foods high in magnesium, such as spinach, kale, and collard greens, may support normal testosterone levels.
Healthy fat, protein, and selenium, a mineral that functions as an antioxidant in the body, are abundant in egg yolks.
According to research in test tubes and animals, selenium may increase testosterone production by activating specific pathways and activating specific genes.
Human and animal research have discovered that individuals with the highest blood levels of selenium also had greater testosterone levels.
However, more research is required before any generalizations concerning selenium's impact on testosterone are made, particularly in human beings.
Unless you have an egg allergy, it is a good idea to include eggs in your diet if they aren't already. Eggs are very nutrient-dense. Since the yolks contain most of the vitamins, keep in mind that whole eggs are significantly more nutrient-dense than egg whites.
Stress is a strong emotion that profoundly affects your hormones, especially your stress hormones. It is considered that males may create less testosterone when stress is strong and unresolved. The tendency for a relationship between stress and testosterone to quickly spiral out of control is concerning. More stress on the body due to low testosterone levels can cause those levels to fall even lower. It is why treating hormone problems brought on by stress may be so challenging. What causes this to occur?
Researchers are still learning more about the direct physiological link between stress and low testosterone. Your low testosterone levels may also result from some stress-related side effects, such as loss of motivation, poor sleep, and decreased energy, in addition to the physical reaction your body will experience.
Although this can be upsetting, experts contend that stress management can assist in reducing low testosterone symptoms. Additionally, lowering your hormone levels can lessen your sensitivity to stress. Working on stress management is one of the first things you can do to address your low testosterone symptoms.
Here are a few things you can try to improve your stress and start noticing improvements in how you look and feel, even if it can be challenging to notice:
Weight Loss: Your mood can be improved by diet and exercise, and it has been demonstrated that testosterone levels can rise when weight is lost.
Increasing Sleep: Low testosterone levels can result from sleep deprivation, but testosterone levels that average eight hours per night can rise.
Better Diet: High-protein, low-fat diets can help regulate those testosterone levels, according to experts.
Exercise: Endorphins, which can lower stress and increase testosterone levels, can be released by engaging in sufficient aerobic exercise. Additionally, your testosterone levels will naturally rise when you work out and add lean muscle to your body.
Take a Vitamin D Supplement
Vitamin D is a crucial mineral that supports bone health and works to stave against osteoporosis, a disorder marked by fragile and brittle bones. Additionally, it promotes normal nerve and muscle function. Vitamin D can be obtained from food sources, such as fish, eggs, and fortified milk, or made in the skin after exposure to sunlight. However, many people do not get enough vitamin D from their diet or sun exposure. As a result, they may need to take a supplement to ensure they are getting enough.
What does any of this have to do with testosterone specifically? Low vitamin D levels can also produce depression, which can mimic the signs and symptoms of low testosterone, such as erectile dysfunction and a diminished sex drive found in testosterone insufficiency. Additional indications of vitamin D insufficiency and low testosterone include:
- Weakened bone and muscle mass
It's advisable to first confirm low levels of testosterone or vitamin D with a blood test and then, for most people, focus on improving them individually. But what is the link between vitamin D and testosterone?
Although studies have revealed that consuming vitamin D may impact testosterone for certain people, the relationship between vitamin D and testosterone is not well understood.
One study focused on middle-aged males with low testosterone and vitamin D levels. Both their vitamin D and testosterone levels increased after taking vitamin D supplements. However, studies also revealed that testosterone levels in healthy, middle-aged men did not change after taking vitamin D supplementation.
The fact that fat cells have a high concentration of an enzyme called aromatase, a protein that speeds up chemical reactions, is one of many factors that obesity has been linked to low testosterone levels. The primary duty of aromatases is to create estrogen from testosterone molecules (estrogen is the primary female sex hormone; however, men also require this hormone at much smaller levels).
Therefore, as a man begins to acquire weight through additional adipose tissue, his testosterone is converted into estrogen by an increasing number of aromatases. His testosterone levels will start to drop as a result. (Under normal circumstances, aromatases only convert a small portion of your testosterone to estrogen, ensuring that you have the proper estrogen level, neither too little nor too much.)
Additionally, abdominal fat is known to create exceptionally high levels of aromatases; therefore, if a man's excess pounds tend to concentrate in this area of his body, it can be highly detrimental to his testosterone levels. But there are other factors at play when it comes to low testosterone.
When the hypothalamus and pituitary glands in the brain receive signals from your body that more testosterone is required, the testes in males produce testosterone. Your testes respond to a chemical communication from these glands by increasing testosterone production.
Estrogen, in this scenario, is the wrench that fat can throw in this process. In other words, there is evidence that estrogen can reduce testosterone production by telling your hypothalamus and pituitary glands to release hormones that inform your brain that it no longer needs to produce testosterone.
Dr. Peter Bajic, MD, argues that weight loss is necessary since estrogen is produced by the body's fat cells when testosterone is present. "This conversion can be stopped, and testosterone levels can naturally rise with weight loss. Not all overweight men with low testosterone, though.
According to research, testosterone levels below 300 ng/dL, or hypogonadism, are present in over 50% of obese males. It is supported by a study of obese men who underwent weight loss surgery, which discovered that, within a year after the procedure, their testosterone levels increased from an average of 295 ng/dL before surgery to 423 ng/dL afterwards.
Get Adequate Sleep
The body's required amounts of hormones and substances, including testosterone, can be negatively impacted by sleep deprivation.
Men who don't get enough sleep may see a decline in testosterone levels, according to a University of Chicago study.
Ten healthy males in their mid-twenties slept eight hours per night at home for a week before spending the following eleven nights in a lab. They slept for 10 hours every night for three nights, then only got 5 hours of sleep for eight nights. During the previous night, when they slept for 10 hours and during the sleep-restricted period, doctors examined their blood every 15 to 30 minutes.
The researchers discovered that testosterone levels in the daytime decreased by up to 15% after just one week of sleep deprivation. Compared to normal aging, testosterone drops by just 1% to 2% annually.
Prioritizing sleep could keep testosterone levels in check. Aim for sleeping for at least 7 to 8 hours every night. Anyone who consistently has trouble sleeping soundly should consult their doctor.
Take DMoose Testosterone Booster Supplement
Low testosterone levels can lead to various health problems, including fatigue, muscle weakness, and decreased sex drive. Testosterone booster supplements are designed to help improve testosterone levels by providing the body with the necessary nutrients to produce more of the hormone.
One of the best testosterone booster supplements is by DMoose. It has all the key ingredients that help improve the testosterone level and improve overall health. The supplement can help improve energy levels, build muscle, and increase sex drive by providing the body with these building blocks to produce more testosterone. This supplement's most beneficial ingredients for boosting testosterone levels are discussed below.
It has aspartic acid, an amino acid that has been shown to stimulate testosterone production. Unlike other amino acids, aspartic acid is not used to build proteins. Instead, it plays a role in synthesizing proteins and other molecules. Aspartic acid helps to increase the level of testosterone by stimulating the release of luteinizing hormone from the pituitary gland. Luteinizing hormone then triggers the production of testosterone in the testes. In addition, aspartic acid helps increase the level of glutathione, an important antioxidant that helps protect cells from damage. As a result, aspartic acid can help to improve testosterone levels and overall health.
Another common ingredient is Tribulus terrestris. It is a small, leafy plant native to southern Europe and Asia. Also known as puncture vine, Tribulus has been used in traditional Chinese and Ayurvedic medicine for centuries. Today, Tribulus is sometimes taken as a supplement to improve athletic performance or sexual function. Tribulus is thought to work by boosting testosterone levels, a hormone that plays a crucial role in male fertility and muscle growth. While Tribulus does contain compounds that can potentially increase testosterone levels, there is currently no reliable evidence to support these claims. In addition, Tribulus may cause side effects such as stomach upset, headache, and difficulty sleeping.
Fenugreek is an aromatic herb used in traditional Indian and Chinese medicine for centuries. Studies suggest that fenugreek may help to increase testosterone levels and improve male sexual function. Fenugreek is thought to work by increasing the production of luteinizing hormone, which stimulates the testes to produce more testosterone. Additionally, fenugreek contains compounds that may help to block the conversion of testosterone to estrogen. These properties make fenugreek a popular natural remedy for low testosterone levels. However, more research is needed to confirm its efficacy. Nevertheless, fenugreek is generally considered safe and may be worth trying for men experiencing low testosterone symptoms.
DMoose testosterone booster also contains L-arginine, an amino acid that has many benefits for the human body, one of which is its ability to improve testosterone levels. In addition, L-arginine can also help to improve blood flow, which can enhance muscle pumps during workouts. Moreover, L-arginine can increase nitric oxide levels in the body, leading to improved recovery from exercise. For these reasons, L-arginine is a popular supplement among athletes and fitness enthusiasts.
We have discussed a few different ways that you can improve your testosterone levels. While some of these methods, such as boosting your vitamin D intake or getting adequate sleep, are relatively easy to do, others, like weight loss and exercise, may require more effort.
If you are looking for an easier solution, testosterone-boosting supplements can be a great way to go. Make sure you research before purchasing any product and speak with a healthcare professional if you have any concerns. Remember that consistency is key in whichever route you choose, so stick with it and see results.
- Ari, Zeki, et al. “Serum Testosterone, Growth Hormone, and Insulin-like Growth Factor-1 Levels, Mental Reaction Time, and Maximal Aerobic Exercise in Sedentary and Long-Term Physically Trained Elderly Males.” The International Journal of Neuroscience, vol. 114, no. 5, May 2004, pp. 623–37. PubMed, https://doi.org/10.1080/00207450490430499.
- Chen, Chi, et al. “Causal Link Between Vitamin D and Total Testosterone in Men: A Mendelian Randomization Analysis.” The Journal of Clinical Endocrinology and Metabolism, vol. 104, no. 8, Aug. 2019, pp. 3148–56. PubMed, https://doi.org/10.1210/jc.2018-01874.
- Craig, B. W., et al. “Effects of Progressive Resistance Training on Growth Hormone and Testosterone Levels in Young and Elderly Subjects.” Mechanisms of Ageing and Development, vol. 49, no. 2, Aug. 1989, pp. 159–69. PubMed, https://doi.org/10.1016/0047-6374(89)90099-7.
- Di Blasio, Andrea, et al. “Acute and Delayed Effects of High Intensity Interval Resistance Training Organization on Cortisol and Testosterone Production.” The Journal of Sports Medicine and Physical Fitness, vol. 56, no. 3, Mar. 2016, pp. 192–99.
- Golan, Ron, et al. “Age-Related Testosterone Decline Is Due to Waning of Both Testicular and Hypothalamic-Pituitary Function.” The Aging Male : The Official Journal of the International Society for the Study of the Aging Male, vol. 18, no. 3, 2015, pp. 201–04. PubMed Central, https://doi.org/10.3109/13685538.2015.1052392.
- Hackney, A. C., et al. “Testosterone Responses to Intensive Interval versus Steady-State Endurance Exercise.” Journal of Endocrinological Investigation, vol. 35, no. 11, Dec. 2012, pp. 947–50. PubMed, https://doi.org/10.1007/BF03346740.
- HAWKINS, VIVIAN N., et al. “Effect of Exercise on Serum Sex Hormones in Men: A 12-Month Randomized Clinical Trial.” Medicine and Science in Sports and Exercise, vol. 40, no. 2, Feb. 2008, pp. 223–33. PubMed Central, https://doi.org/10.1249/mss.0b013e31815bbba9.
- Hyder Qazi, Izhar, et al. “Role of Selenium and Selenoproteins in Male Reproductive Function: A Review of Past and Present Evidences.” Antioxidants, vol. 8, no. 8, 2019, p. 268, https://doi.org/10.3390/antiox8080268.
- Kumagai, Hiroshi, et al. “Increased Physical Activity Has a Greater Effect than Reduced Energy Intake on Lifestyle Modification-Induced Increases in Testosterone.” Journal of Clinical Biochemistry and Nutrition, vol. 58, no. 1, Jan. 2016, pp. 84–89. PubMed Central, https://doi.org/10.3164/jcbn.15-48.
- Kurniawan, Adi-Lukas. “Association of Testosterone-Related Dietary Pattern with Testicular Function among Adult Men: A Cross-Sectional Health Screening Study in Taiwan.” Nutrients, vol. 13, no. 1, Jan. 2021, p. 259, https://doi.org/10.3390/nu13010259.
- Leproult, Rachel, and Eve Van Cauter. “Effect of 1 Week of Sleep Restriction on Testosterone Levels in Young Healthy Men.” JAMA, vol. 305, no. 21, June 2011, pp. 2173–74. Silverchair, https://doi.org/10.1001/jama.2011.710.
- Lerchbaum, Elisabeth, et al. “Vitamin D and Testosterone in Healthy Men: A Randomized Controlled Trial.” The Journal of Clinical Endocrinology and Metabolism, vol. 102, no. 11, Nov. 2017, pp. 4292–302. PubMed, https://doi.org/10.1210/jc.2017-01428.
- M Al-Olayan, Ebtesam, and Manal F. El-Khadragy. “Protective Effects of Pomegranate (Punica Granatum) Juice on Testes against Carbon Tetrachloride Intoxication in Rats.” BMC Complementary Medicine and Therapies, vol. 14, 2014, p. 164, https://doi.org/10.1186/1472-6882-14-164.
- M Traish, Abdulmaged. “Testosterone and Weight Loss: The Evidence.” Current Opinion in Endocrinology, Diabetes, and Obesity, vol. 21, no. 5, 2014, pp. 313–22, https://doi.org/ 10.1097/MED.0000000000000086.
- Maggio, M., et al. “Magnesium and Anabolic Hormones in Older Men.” Int J Androl, June 2011, pp. e594–600, https://doi.org/ 10.1111/j.1365-2605.2011.01193.x.
- Nindl, B. C., et al. “Testosterone Responses after Resistance Exercise in Women: Influence of Regional Fat Distribution.” International Journal of Sport Nutrition and Exercise Metabolism, vol. 11, no. 4, Dec. 2001, pp. 451–65. PubMed, https://doi.org/10.1123/ijsnem.11.4.451.
- Pilz, S., et al. “Effect of Vitamin D Supplementation on Testosterone Levels in Men.” Hormone and Metabolic Research = Hormon- Und Stoffwechselforschung = Hormones Et Metabolisme, vol. 43, no. 3, Mar. 2011, pp. 223–25. PubMed, https://doi.org/10.1055/s-0030-1269854.
- Pizzorno, Lara. “Nothing Boring About Boron.” Integrative Medicine - A Clinician’s Journal, no. 4, Aug. 2015, pp. 35–48, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4712861/.
- Rondanelli, Mariangela, et al. “Pivotal Role of Boron Supplementation on Bone Health: A Narrative Review.” Journal of Trace Elements in Medicine and Biology, vol. 62, Dec. 2020, p. 126577. ScienceDirect, https://doi.org/10.1016/j.jtemb.2020.126577.
- Scovell, Jason M., et al. “Hypogonadal Symptoms in Young Men Are Associated with a Serum Total Testosterone Threshold of 400 Ng/DL.” BJU International, vol. 116, no. 1, July 2015, pp. 142–46. DOI.org (Crossref), https://doi.org/10.1111/bju.12970.
- Shi, Lei, et al. “Effects of Selenium on the Proliferation, Apoptosis and Testosterone Production of Sheep Leydig Cells in Vitro.” Theriogenology, vol. 93, Apr. 2017, pp. 24–32. PubMed, https://doi.org/10.1016/j.theriogenology.2017.01.022.
- Timón Andrada, Rafael, et al. “Variations in Urine Excretion of Steroid Hormones after an Acute Session and after a 4-Week Programme of Strength Training.” European Journal of Applied Physiology, vol. 99, no. 1, Jan. 2007, pp. 65–71. PubMed, https://doi.org/10.1007/s00421-006-0319-1.
- Vaamonde, Diana, et al. “Physically Active Men Show Better Semen Parameters and Hormone Values than Sedentary Men.” European Journal of Applied Physiology, vol. 112, no. 9, Sept. 2012, pp. 3267–73. PubMed, https://doi.org/10.1007/s00421-011-2304-6.
- Weiss, Lawrence W., et al. “Comparison of Serum Testosterone and Androstenedione Responses to Weight Lifting in Men and Women.” European Journal of Applied Physiology and Occupational Physiology, vol. 50, no. 3, Mar. 1983, pp. 413–19. Springer Link, https://doi.org/10.1007/BF00423247.