Best Ways to Increase Testosterone and IGF-1 Thru Diet, Exercise, and Lifestyle and Supplements.
By: Robbie Durand
Two of the most widely known anabolic for muscle growth and strength are testosterone and IGF-1. Both hormones are influenced by diet, exercise, and lifestyle. The prevailing dogma for the past 50 years has been that testosterone increases muscle mass by stimulating muscle protein synthesis and also increases other muscle growth factors. Testosterone administration also results in increases in GH secretion, androgen receptor number, satellite cell activity, and increased IGF-I expression in skeletal muscle. It’s also Also that the increase in muscle anabolism is associated with an increase in the expression of intramuscular mRNA IGF-I.
Lifestyle Factors Influencing Anabolic Hormones: Sleep
Sleep is one of the most neglected aspects of health for most athletes. Athletes will not think twice about staying up a little later if they can get more things done. Not getting a good night’s sleep can not only affect performance but it can also impact your gains in the gym.
Sleep Loss Lowers Testosterone
Plasma testosterone levels display circadian variation (i.e. highest in the morning and gradually decreasing throughout the night), however, during sleep, testosterone peaks. Various disorders of sleep including abnormalities of sleep quality, duration, circadian rhythm disruption, and sleep-disordered breathing may result in a reduction in testosterone levels. One cross-sectional study examined the different associations of age and sleep duration with sex steroid hormones and sexual activities in 531 Asian Chinese men aged between 29 and 72 years old. Age was a significant determinant of sleep, sex steroid hormones, and sexual activities in men. Bioavailable testosterone, DHEAS, sex frequency, masturbation, and sleep duration declined with age. On the other hand, SHBG and estrogen increased with age. Sleep duration, independently of age, aerobic exercise, and body fat, was positively associated with testosterone and bioavailable testosterone, but not with DHEA, estrogen, or any of the sexual activities studied. Men who masturbated had higher levels of both testosterone and bioavailable testosterone. DHEAS was significantly associated with sex frequency and desire for sex. The study showed that besides age, sleep duration was related to androgen concentrations in men, and thus the evaluation of sleep hygiene may be beneficial in the management of men with low androgen levels.
Get Your Sleep for Optimal Testosterone Production
Another study examined 531 healthy men as testosterone levels among subjects, and they examined how the amount of sleep correlated with their testosterone level. The results again show that the men who slept more also had significantly higher testosterone levels. In fact, the guys who slept for 4 hours had about 60% less testosterone in their serum, than the men who slept for 8 hours sleeping and male testosterone levels. If you want low testosterone levels, sleep less than four hours a night. In another study, Twelve healthy men age 64 to 74 years were examined. Three-morning blood samples were pooled for the measurement of total and free testosterone. The primary outcome measures were total sleep time and morning testosterone levels. Sleep time in the laboratory was correlated with the usual amount of nighttime sleep at home. The researchers reported that the amount of nighttime sleep measured was an independent predictor of the morning total and free testosterone levels of the subjects. The differences in the measured amount of nighttime sleep are associated with a significant part of the variability in the morning testosterone levels of healthy older men. If you want optimal testosterone levels, you should be sleeping more than eight hours a day.
Sleep and IGF-1
Similar to testosterone, serum IGF-1 also is correlated to sleep. Serum levels of IGF-I are modulated by different physiological (age, gender, nutrition, exercise, sleep, etc.) and pathological (illness, stress, etc.) conditions. In one previous study, a relationship between sleep and IGF-I levels was reported, as IGF-I levels co-vary significantly with slow wave sleep in healthy senior men. Acute or chronic sleep deprivation was found to induce a catabolic state with reduction of circulating IGF-I and GH levels in rats and healthy humans. Extending sleep can enhance IGF-1 according to new research. Researchers examined the effect of 6 nights of extended sleep (72 extra minutes of sleep) before total sleep deprivation on this catabolic profile. In a randomized cross-over design, 14 young men (age: 26-37 years) were either in extended or habitual sleep condition (extended sleep 9:00 PM- 07:00 AM or 12:30AM – 07:00 AM, time in bed), followed by three days in the laboratory with blood sampling at baseline, after 24 hours of sleep deprivation, and after one night of recovery sleep. Under extended sleep compared to regular sleep, free and total IGF-I levels were significantly higher at baseline, 24h-after sleep deprivation and recovery. In sum, healthy adults getting additional sleep over one week increased blood concentrations of the anabolic factor IGF-I before and during 24 hours of sleep deprivation.
Testosterone and IGF-1 Boost Muscle Anabolism
For years, bodybuilders have been advocated to use short rest periods between sets to elicit metabolic stress and increase anabolic hormone responses. Various hormones have been shown to alter the dynamic balance between anabolic (i.e. testosterone, GH, IGF-1) and catabolic (i.e. cortisol) stimuli in muscle, helping to mediate an increase or decrease in muscle protein synthesis. Testosterone is not readily available to the androgen receptor. The vast majority of circulating testosterone is bound to either albumin (38%) or steroid hormone binding globulin (60%), with the remaining 2% flowing in a free, unbound state that is available to bind to the receptor. This means only a subtle portion of free testosterone is readily available to bind to the receptor in muscle.
Metabolic Stress Increases Anabolic Hormones
It is believed that high metabolic stress associated with such routines potentiates post-exercise hormonal release. Resistance exercise that involves high volume training with short rest periods can stimulate anabolic hormones. For example, numerous studies using resistance exercise training combined with blood flow restriction have shown to increase muscle hypertrophy with a training intensity as low as 20% 1RM. For instance, a low-intensity (~50% 1RM) resistance training performed with leg extensions caused a marked increase in muscular size [~12% gain in muscle size and strength (~20% gain) when combined with moderate vascular occlusion. These studies suggest that the muscle mass building effects of resistance exercise involve not only muscle tension (weight) but also metabolic factors such as GH and testosterone.
According to hypertrophy expert, Dr. Brad Brad Schoenfeld, hypertrophy-oriented program to increase testosterone should include a repetition range of 6–12 reps per set with rest intervals of 60–90 seconds between sets. Exercises should be varied in different exercises and different angles to ensure maximal stimulation of all muscle fibers. Multiple sets should be employed with a split training routine to heighten the anabolic hormones response. Concentric repetitions should be performed at fast to moderate speeds (1–3 seconds) while eccentric repetitions should be carried out at slightly slower speeds
Hormones such as human growth hormone (GH), testosterone, and IGF-1 have been shown to play a role in muscle hypertrophy and strength gains. The prevalent dogma for the past 50 years has been that testosterone increases muscle mass by stimulating fractional muscle protein synthesis. Testosterone administration also results in increases in GH secretion, androgen receptor number, satellite cell activity, and increased IGF-I expression in skeletal muscle. It’s also been demonstrated that the increase in muscle anabolism is associated with an increase in the expression of intramuscular mRNA IGF-I. GH is also highly recognized for its role in muscle growth. Resistance exercise stimulates the release of GH from the anterior pituitary gland, with released levels being very dependent on exercise intensity. GH helps to trigger fat metabolism for energy use in the muscle growth process. As well, GH stimulates the uptake and incorporation of amino acids into protein in skeletal muscle. In humans, GH administration is known to increase both whole-body and muscle protein synthesis and almost unequivocally to increase lean body mass and decreased fat mass. Human growth hormone also stimulates the liver production of circulating IGF-1 concentrations and may also stimulate IGF-1 production in other tissue such as skeletal muscle.
Researchers examined in the Journal of Strength and Conditioning Research the impact of post-exercise hormones on muscle growth. Pre-testing measures of muscle size (thickness and cross-sectional area) of the legs were collected in 26 resistance-trained men. Participants were randomly selected to complete a high-volume exercise program consisting of 10–12 repetitions, 1-min rest periods) or high-intensity (3–5 RM, 3-min rest periods) resistance training program. During training, participants were required to complete at least 28 resistance training sessions (~90%) of an 8-wk resistance-training program (4 sessions · week) that included six upper- and lower-body exercises during each session. Blood samples were collected at baseline, immediately post-exercise, 30-min, and 60-min post-exercise during weeks 1 (week 1) and 8 (week 8) of training. At the end of the study, of all the hormones, measured, only post-exercise testosterone is related to muscle hypertrophy across eight weeks of training. There were no significant pathways observed in the other hormones studies such as cortisol, GH, IGF-1, or insulin. The findings indicate that baseline muscle size and the hormonal response to resistance exercise are related to muscle hypertrophy following eight weeks of training.
Best Way to Increase IGF-1 by Exercise
IGF-1 is a powerful anabolic hormone that has direct effects on increasing muscle protein synthesis and has a direct effect on muscle. During exercise, muscles not only produce more IGF-1 than the liver but also use more circulating IGF-1. Levels of IGF-1 then remain elevated in muscle tissue for some time after that, with post-exercise anabolic effects seen up to 72 hours postexercise. One of the most effective ways of increasing muscle IGF-1 is by using eccentric exercise.
Back in the early 90’s, there was a book called Bigger Muscles in 42 Days by Dr. Elliot Darden. The book took a revolutionary approach to training by advocating that people needed to spend less time in the gym but more importantly to emphasize eccentric contractions. If you look at most people train in the gym lifting, they pay little attention to the eccentric or lowering phase of the lift. Lowering the weight under control brings gravity into play in another fashion. During positive work or concentric contractions, muscle fibers are shortening. During negative work or eccentric contractions, the same fibers are lengthening. Although lifting and lowering may seem like a very simple process, the physiological differences to muscle adaption are much different.
Emphasizing the eccentric contraction is associated with positive changes in strength and lean muscle mass. Eccentric contractions are so important that if you remove the eccentric contraction from the lift, strength gains are reduced. In one study, researchers compared a concentric only strength training program to a concentric and eccentric program for five weeks. Subjects who performed the concentric/eccentric training had nearly twice the strength gains as those who only trained only with a concentric contraction only exercise regimen. Another study found that placing an emphasis on the eccentric overload experienced a 46 percent increase in strength in just one week! Also, eccentric exercise primarily activates the fast twitch muscle fibers are more likely to lead to greater muscle soreness and muscle growth.
Eccentric Exercise Increases Muscle Damage
If you look at muscles under a microscope after an intense bout of eccentric exercise, it would seem like a bomb exploded in the muscles. The muscle fibers are pulled apart, and the fibers have increased growth factors at the site of injury repairing the muscle fibers. Researchers have long been aware that maximal eccentric contractions result in more muscle damage and more muscle tissue growth, but researchers wanted to compare the differences between maximal concentric contractions and maximal eccentric contractions and how they affected satellite cells.
Satellite cells are essential for muscle growth and repair, without the activation of satellite cells, muscle won’t grow. Satellite cells are so important for muscle growth that if you prevent satellite cells from being activated after an intense muscle overload, there is no muscle growth despite being damaged by tension overload. Optimal repair and adaptation of skeletal muscle is facilitated by resident stem cells (satellite cells). To understand how different exercise modes influence satellite cell dynamics, researchers measured satellite cell activity in conjunction with markers of muscle damage and inflammation in human skeletal muscle following a single work- and an intensity-matched bout of eccentric or concentric contractions. Participants completed a single bout of eccentric or concentric of the knee extensors. A muscle biopsy was obtained before and 24 hours after exercise. At the end of the study, peak torque decreased following eccentric exercise but not concentric exercise. The researchers found that in the eccentric group, satellite cell content per muscle fiber increased significantly (by 27%), but there was no significant increase in the concentric group. In conclusion, eccentric but not concentric results in functional and histological evidence of muscle damage that is accompanied by increased satellite cell activity 24 hours post-exercise. The research study should be a real wake-up call for those athletes that want to grow, to emphasize eccentric contractions during their weight training by lowering the weight slowly with the heaviest weight possible.
Fats and Testosterone
In the early 80 and 90’s, low-fat diets were the mainstream way to lose weight. It was a diet of chicken breasts and egg whites because we had the misconception that fats were unhealthy. What we do know today is that dietary fat provide the building blocks to support optimal testosterone production. Testosterone levels reach a peak during a man’s twenties and subsequently decline over a man’s lifetime. Aging and lifestyle factors such as stress, improper diet, physical inactivity, smoking, drinking, lack of sleep and the use of prescription medications can significantly reduce testosterone levels. Most men don’t associate food with testosterone, but if you’re not getting enough fat in your diet, you may be hurting your bodies natural testosterone production. One of the fascinating studies suggesting that diet can raise testosterone was conducted in 2000 when researchers compared serum sex hormone levels in 42 men who ate lean meat 150 g or tofu 290 g daily and found a significantly higher ratio of testosterone to estradiol levels in meat eaters.
Two major studies examining vegan diets to those of meat eaters found that vegan diets elevated the hormone sex hormone binding globulin which binds to testosterone. Excessively high SHBG is problematic especially for males and athletes because it decreases the amount of free testosterone. Elevated levels of SHBG are associated with infertility, a decreased sex drive, and erectile dysfunction, especially when total testosterone levels are already low. Another factor that increases SHBG is overtraining. In a 2011 Finnish study, researchers assessed the impacts of overtraining on levels of SHBG and total testosterone. Researchers examined military recruits undergoing intense military training. The physical regimen started at 2 hours/day in week one and increased to 7 hours/day by week 8. The researchers took blood samples of the subjects after 12 hours of fasting before weeks 1, 4, and seven where the first blood sample served as the baseline blood levels of SHBG and total testosterone. Researchers revealed that total testosterone remained the same as baseline while serum SHBG concentrations increased gradually over the study. Because of the increase in SHBG and the same level of TT, the free serum testosterone levels decreased resulting in lower muscle recovery and ultimately poorer physical performance. In another study, two elite ice hockey teams were put on different diets for seven months. One group received a diet higher in fat and lower in carbs containing 40% fat and 45% carbs, whereas the other team ate less fat and more carbs with 30% fat and 55% carbs (protein intake was identical). Both during and after the study, the researchers saw that the higher fat intake group had higher free testosterone levels, along with lower sex hormone binding globulin (SHBG) levels.
What Types of Fats Are Best?
Most men need a mix of mono and saturated fats to optimize testosterone levels. It seems that polyunsaturated fats and transfats are associated with a decrease in testosterone. In one study the type of lipid appears to influence circulating T concentrations. In this study, Mono and Saturated fats were the strongest predictors of increased testosterone levels. Cortisol concentrations in this study were not affected by dietary fat. However, this study did not specifically look at the effects of essential fatty acids. Olive oil is a fundamental food in the Mediterranean diet, which has reported beneficial effects on sexual function. One study reported an increase in serum total testosterone and luteinizing hormone after three weeks’ consumption of 25 mL of virgin argan oil or extra virgin olive oil compared with baseline in 60 men 23 to 40 years old, with no real difference between the two oils. Another study in rats found that both olive oil and coconut oil could enhance testosterone production. For sixty days, the rats were given feed to which seventy grams of soya oil, olive oil, coconut oil, or grapeseed oil per kilogram had been added. At the end of the study, the researchers were interested in how much testosterone levels changes at the end of the study.
Olive oil was the best fat for raising testosterone, but olive oil had a few other potent beneficial effects. The researchers also found a relationship between the diet, the amount of free cholesterol in the Leydig cells and the testosterone level. The Leydig cells make testosterone from cholesterol. A diet that is rich in coconut oil or olive oil apparently helps the cells to absorb more cholesterol. Cholesterol is vital per-cursor for testosterone production. So natural athletes could optimize their testosterone production by making olive oil their primary source of fat. Olive oil and coconut oil also raise the concentration of the body’s antioxidants in the Leydig cells, which produce testosterone. Another theory is that leydig cells begin to produce less testosterone due to cell damage from free radicals, the antioxidants in olive oil, and coconut oil may prevent cell damage. Olive oil and coconut oil also increased the two enzymes necessary for testosterone production which were 3-beta-HSD and 17-beta-HSD. This was done in cell cultures, so it’s not conclusive evidence that it works in real life. There has never been a study in humans to show that olive oil or coconut oil raises testosterone levels in man, but the study is interesting nevertheless.
Fats are important constituents of our diet and, beside their functions as sources of energy and carriers for fat-soluble vitamins, they supply essential fatty acids that are vital components of cell membranes and precursors for hormones such as testosterone. Fats are necessary for optimal testosterone production, but there is one fat you need to avoid if you want optimal testosterone production…Trans-Fatty Acids or hydrogenated fats.
Trans Fats are Testosterone Lowering
Trans fats (or trans-fatty acids) are created in an industrial process that adds hydrogen to liquid vegetable oils to make them more solid. The primary dietary source of trans fats in processed food is “partially hydrogenated oils.” Trans fats give foods a desirable taste and texture. Many restaurants and fast-food outlets use trans fats to deep-fry foods because oils with trans fats can be used many times in commercial fryers. Many cheap, packaged foods are full of trans fat (i.e. low-cost microwave popcorn, and peanut butter), as are many frozen foods (such as frozen pizza, packaged pastries, cakes, etc.). Fried foods are often cooked in trans fat.
Most of the research has reported that saturated fats have a positive impact on testosterone, trans fats have a negative impact on testosterone. The good news is that the FDA is banning the use of partially hydrogenated oils, the main source of artery-clogging artificial trans fats, in processed food. Food makers will have three years to remove partially hydrogenated oils from products, according to the recent FDA ruling. Given that the FDA’s statement says that “there is no safe level of consumption of artificial trans fat.” Scientists are well aware of the negative risks on trans-fatty acids on heart disease, but a lesser known role is the effect on testosterone levels. In addition, experimental evidence in rodent models suggests that intake of trans fats can cause impaired spermatogenesis and testicular damage.
Here is a 1976, 1989, and 2007 study on Trans fats and Rats:
Wistar rats were fed for three successive generations on a semi-purified diet, in which the fat was provided by butter, sunflower oil, rapeseed oil or hydrogenated vegetable fat, differing in the content of cis,cis-18:2 and trans-18:1 fatty acids. Effects of these fats on the composition of adipose tissue and reproductive performance were studied. Hydrogenated fat decreased the level of serum testosterone in male rats. Furthermore, this type of supplementation with trans-fatty acids leads to a number of adverse male reproductive outcomes including reduced fertility, decreased serum testosterone levels, decreased sperm count, motility and normal morphology and, in extreme cases, arrest of spermatogenesis and testicular degeneration.
A 2013 study in Spain with over 2019 men reported that trans-fatty acids reduced sperm quality in young men. Spain has seen an increase in the proportion of calories consumed as fat over the same period that a downward trend in semen quality has been observed. Also, rodent models suggest that trans fat intake may severely affect testicular function. Researchers recruited 209 healthy young university students, 18–23 years of age, each provided a semen sample and completed a previously validated food frequency questionnaire. The association between intake of fatty acids with semen quality parameters (sperm concentration, motility, morphology and total count) was assessed using multivariate linear regression. At the end of the study, Trans-fatty acid intake was inversely related to total sperm count after adjusting for potential confounders. Intake of trans-fatty acids, primarily derived from french fried potatoes and commercially baked items, was inversely related to total sperm count. Intake of other fatty acids was not significantly related to semen parameters. This means the more trans-fatty acids the young men consumed, the less sperm production they had. The results of this study, together with previous experimental work in rodents and biomarker studies among infertility patients, suggest that intake of trans-fatty acids may be related to lower semen quality. Although the data provide further evidence that diet is a modifiable factor that could impact male fertility, it is not known whether the observed differences in sperm count translate into differences in fertility.
So the bottom line is, avoid fast food restaurants at all costs because they are the primary sources of trans-fatty acids in their foods.
Supplements for Testosterone
Fenugreek is a herb that is commonly found growing in the Mediterranean region of the world. Fenugreek seeds have been found to contain protein, vitamin C, niacin, potassium, and diosgenin. Other active constituents in fenugreek are alkaloids, lysine, and L-tryptophan, as well as steroidal saponins (diosgenin, yamogenin, tigogenin, and neotigogenin). Fenugreek glycosides are reported to be major components of health benefits of fenugreek seeds. Recently, Fenugreek has been found to have performance-enhancing effects mediated through an aromatase and 5α reductase inhibition, thereby increasing total testosterone levels by blocking its conversion to estrogen and dihydrotestosterone (DHT), respectively. Fenugreek also increases total and free testosterone. One study found that fenugreek increased The bio-available testosterone by 26 percent. In a different study, conducted by the Journal of the International Society of Sports Nutrition, researchers found that fenugreek had a significant impact on upper and lower body strength and body composition in comparison to placebo in a double-blind controlled trial. TESTOFEN is a product containing fenugreek seed extract as an active ingredient.
A new study published in the Journal of Aging Males just released a new paper titled, “Testofen, a specialized Trigonella foenum-graecum seed extract reduces age-related symptoms of androgen decrease, increases testosterone levels and improves sexual function in healthy aging males in a double-blind randomized clinical study” reports Testofen supports testosterone enhancement. The study examined the effect of Testofen; a fenugreek extract specialized Trigonella foenum-graecum seed extract on the symptoms of possible androgen deficiency, sexual function, and serum androgen concentrations in healthy aging males. This was a double-blind, randomized, placebo-controlled trial involving 120 healthy men aged between 43 and 70 years of age. The active treatment was standardized Trigonella foenum-graecum seed extract at a dose of 600 mg/day for 12 weeks. The primary outcome measure was the change in the Aging Male Symptom Questionnaire (AMS), a measure of possible androgen deficiency symptoms; secondary outcome measures were sexual function and serum testosterone. There was a significant decrease in Aging Male Symptom Questionnaire score over time and between the active and placebo groups. Sexual function improved, including number of morning erections and frequency of sexual activity. Both total serum testosterone and free testosterone increased compared to placebo after 12 weeks of active treatment of Testofen. Trigonella foenum-graecum seed extract is a safe and efficient treatment for reducing symptoms of possible androgen deficiency, improves sexual function and increases serum testosterone in healthy middle-aged and older men.
3 Grams of Leucine After Exercises Increases IGF-1 Levels in Muscle
To demonstrate the potent muscle building properties of leucine. Nine trained men performed 3 lower-body resistance exercise sessions involving 4 sets of 8–10 repetitions at 75%–80% one repetition maximum on the angled leg press and knee extension exercises. Immediately following each session, participants orally ingested:
– 3 g cellulose placebo or
– 3 grams of L- leucine
Blood samples were obtained pre-exercise and at post exercise, 2, and 6 hours postexercise. Muscle biopsies were obtained pre-exercise and at 2 and 6 hours postexercise. At the end of the study, supplementation did not induce increases in serum IGF-1; however, skeletal muscle IGF-1 concentrations were significantly increased at 2 and 6 hours postexercise in response to the leucine supplementation.
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