Growth hormone, produced by the pituitary gland, stimulates the production of protein in muscle cells and the release of energy from the breakdown of fats. The amino acid combination of L-lysine and L-arginine pyroglutamate was used in a landmark study to promote the release of human growth hormone (HGH).
Certain nutrients assist in the body's utilization of lipids (fats) for energy. Choline and inositol metabolize and remove fats from the liver. Also, the amino acid L-carnitine assists in the transport of fats into the mitochondria (the energy factories) of muscle cells for fuel during activity.
A strenuous aerobic or anaerobic workout puts great demands on the body. To respond to this stress, the adrenal glands produce hormones such as cortisol. Nourishing the adrenals is an important factor in exercise recovery. As men turn 40, only about 2% of testosterone are free and 98% of testosterone are bound by Sex Hormone Binding Globulin (SHBG). Free testosterone is responsible for providing the body with energy, and enhancing sport performance.
Exercise and nutrition are critical for muscle development. The branched chain amino acids, L-leucine, L-isoleucine, and L-valine, are important components of muscle tissue and are taken into muscle cells preferentially. These aminos help muscle growth and protein synthesis by enhancing the uptake of other amino acids into muscle cells. The body also uses the branch-chain aminos as alternate fuel sources, sparing muscle breakdown.
Skeletal muscles must have energy reserves to cope with bursts of activity. Fatty acids are the main energy source in skeletal muscle of endurance athletes, such as long distance runners. During short-term sprint or power exercises, muscles rapidly metabolize ATP, phosphocreatine and glucose from glycogen stores. To support immediate and sustained energy, branched chain amino acids may be utilized as an energy source for the muscles.
Eurycoma Longifolia, (commonly known as Tongkat Ali or Long Jack), has been used for centuries in SE Asia to increase male virility and sexual prowess. Research has shown Tongkat Ali to increase the testosterone level by 440% in human testicular tissue and increase the frequency and length of sexual performance of the animals studied. Eurycoma has shown in human clinical trials - an ability to increase DHEA, increase free testosterone, and decrease Sex Hormone Binding Globulin (SHBG).
In 9 volunteers that took 100mg of LJ100 daily for 10 days, volunteers that engaged in regular exercise experience a significant increase in free testosterone from 70% to 132%. Volunteers that do not engaged in regular exercise experience an increase in free testosterone of 35% to 70%
In another human clinical study, 14 athletes received either 100 mg/day LJ100 ® (22% Bioactive Eurypeptides) (n = 7) or placebo (n = 7) for 8 weeks. Simultaneously, both groups performed an intensive strength training programs. Results showed that the LJ100® group experienced significant increase in fat free mass (FFM), reduce body fat percentages (FM), increase gross muscle power (1RM), increase significantly arm circumference, and decrement in the mean sEMG reading.
30 volunteers were recruited from a 24-hour mountain biking event; 15 were given 100mg of LJ100, and 15 were given placebo. 8 saliva samples were collected over a 24h period. Cortisol levels were 32.3% lower in the LJ100 compared to Placebo. Testosterone levels were 16.4% higher in the LJ100 group compared to Placebo. By promoting an anabolic state, LJ100® helps the athletes to improve endurance and shorten recovery time.
In Europe, tribulus has been used in folk medicine throughout history. Because of the plants reputed benefits, athletes have used Tribulus Terrestris extract dietary supplements to boost energy levels, to promote healthy hormone function, to enhance muscle tone and to support athletic training. Tribulus increase both free and total testosterone levels, thereby enhancing muscle building property.
Tribulus from Bulgaria contains Protodioscin, which may have effect on sport performance as they regulate energy level and stamina by increasing the percentage of free testosterone level for men. Researchers have credited protodioscin's physiological effects as being the main source of Tribulus' T-boosting power because of its remarkable ability to enhance testosterone precursors such as dehydroepiandrosterone and dehydroepiandrosterone sulphate. As a result, protodioscin-rich Tribulus extracts have been shown to directly elevate the "master" of all muscle-building hormones, testosterone, and its precursor, luteinizing hormone.
Tribulus terrestris works by increasing the amount of Luteinizing Hormone (LH) produced by the body's pituitary gland. LH stimulates the testes to secret the male hormone testosterone. This physiological activity is of primary importance to athletes because higher "T" levels correlate directly to increased anabolism and greater strength.
In a study by Milanov et al. (1981), 8 healthy male subjects aged 28 to 45 years were administered 250 mg of Tribulus terrestris, three times daily at 8-hour intervals for 5 days. Luteinizing hormone levels are markedly elevated, plasma testosterone increased by 40%,
Glycine-l-arginine-alpha-ketoisocaproic acid calcium (GAKIC) is the newest nitric oxide combining Glycine and L Arginine together. In a double-blind, randomized, crossover-designed study conducted at the University of Florida by Stevens et al. (2000), participants ingested either glycine-l-arginine-alpha-ketoisocaproic acid or a placebo (9.46 g sucrose) prior to exercise. After supplementation, subjects performed consecutive right knee concentric and eccentric contractions. Measurements were taken during the last 5 reps of each set. The researchers concluded that glycine-l-arginine-alpha-ketoisocaproic acid calcium treatment increases the ability to sustain muscle force, delays fatigue, and increases total muscle work.
In another double-blind, randomized, crossover-designed study, subjects were given glycine-l-arginine-alpha-ketoisocaproic acid or a placebo before exercise and measured during repeated bouts of anaerobic cycling performance. Results indicated glycine-l-arginine-alpha-ketoisocaproic acid treatment significantly decreased the drop in mean power between the first and second sprints, resulting in a longer time taken to fatigue.
L Arginine AKG —dilates blood vessels, reduces blood pressure, replicates the activity of nitroglycerine, and is needed to produce nitric oxide. L-arginine, along with a properly planned exercise program, assists in amending abnormalities occurring in blood vessels. A study reported in the American College of Cardiology concluded that treatment with L-arginine produced a fourfold increase in blood vessel dilation from 2.2-8.8% (Hambrecht et al. 2000). Regular forearm exercises increased the dilation response by the same amount, but the combination of L-arginine and exercise training resulted in an improvement from 2.9-12%. Doses of 5.6-12.6 grams of arginine increased blood flow to the extremities 29%; the distance walked on a treadmill in 6 minutes increased 8% (Rector et al. 1996).
Much of L-arginine's effectiveness comes by way of increasing nitric oxide, a blood vessel dilator and clot buster produced in endothelial cells by the enzyme nitric oxide synthase (Brunini et al. 2002). Nitric oxide counteracts the vasoconstriction and platelet-aggregating effects of the stress hormone adrenaline (epinephrine) and assists in maintaining vascular elasticity. Nitric oxide (the endothelial relaxing factor) is needed for expansion and contraction of the arterial system (Rohdewald 1999). L-arginine increases nitric oxide, but hypertension, hyperhomocysteinemia, diabetes, and smoking decrease it.
L Arginine is an essential amino acid. It causes the secretion of growth hormone. In fact, a 15 to 30 gram intravenous infusion of arginine is used as a standard endocrinological test to provoke the pituitary into releasing growth-hormone.
A study at the University of Turin, Italy, showed that even though people in their seventies had lower response than either children or young adults to arginine, the nutrient still boosted their blood levels of HGH to triple the average for their age group. Arginine appears to stimulate HGH by blocking the secretion of the growth-hormone inhibitor somatostatin. It also greatly enhances the effect of growth hormone-releasing hormone when they are given together.