Taurine, a semi-essential sulfur-containing β-amino acid, is an organic osmolyte involved in cell volume regulation (by regulating sodium, potassium and magnesium levels), and provides a substrate for the formation of bile salts. It plays a role in the modulation of intracellular free calcium concentration (this aids in muscle relaxation, and prevents involuntary twitchiness, restlessness, etc…), it’s one of the most abundant amino acids in the brain, retina, muscle tissue, and organs throughout the body and is extremely important for the development and health of those tissues.
Taurine can be synthesized from homocysteine. Homocysteine ⇒ cysteine ⇒ taurine. The enzymes involved in this conversion require vitamin B6 and glycine as a cofactor. The body is able to synthesize 50-125mg taurine a day. During stress, this conversion is limited. (R) Also, the availability of cysteine is highly dependent on the metabolic equilibrium between homocysteine and methionine, via folic acid, vitamin B12 and the efficiency of the enzyme methyltetrahydrofolate reductase (MTHFR). Also, many people eat a low protein diet and have improper digestion, and low absorption and utilization of protein, leading to a deficiency in methionine, thus inadequate SAMe is produced and this leads to low homocysteine and ultimately low taurine.
The daily excretion of taurine via the kidney varies, but is usually between 28-231mg per day. A few factors increase the excretion thereof, and one is muscle damage. One reason that guys who workout need more taurine. (R) Also, cortisol, a glucocorticoid, exert an inhibitory action of renal taurine re-uptake which can lead to hypotaurinemia. (R)
Food sources highest which contain the highest amount of taurine are: mussels, turkey (dark meat), clams, chicken (dark meat) as well as other meat in that order.
Taurine promotes muscle growth and exercise performance
1) Taurine promotes insulin sensitivity. Insulin is a very anabolic hormone, and the more sensitive you are to it, the better you’ll be able to build muscle and lose fat (R).
2) It improves mitochondrial function by stabilizing the electron transport chain and inhibiting the generation of reactive oxygen species (ROS) (R, R). This will also lead to less inflammation and better energy production. Building muscle is energy intensive and increasing energy production will aid in muscle growth.
3) Taurine modulates calcium fluxes and enhances muscle contraction and beta-adrenergic activation through its influence on cyclic AMP regulation. (R) Clenbuterol exerts its anabolic function by binding to beta-adrenergic receptors. Taurine exerts the same function, just less powerful. cAMP also activates muscle protein synthesis enzymes and aids in improving hypertrophy.
4) Taurine supplementation has been shown to result in significant increase in VO(2)max, exercise time to exhaustion and maximal workload. It also inhibits exercise induced DNA damage via down-regulation of inducible nitric oxide synthase (iNOS) and consequent reduction of nitrosative inflammation (from elevated ROS) (R, R)
5) Taurine also decreases lipid peroxidation and protects against inflammation and therefor aids in preventing and recovering from muscle damage after a workout. (23) Faster recovery from DOMS.
6) As seen in the following study, taurine (2g x3day) combined with BCAAs a few days prior and post exercise improved muscle recovery in untrained men. (24) I think this is significant, as untrained men experience the greatest muscle soreness post-workout compared to a trained individual.
7) Muscles with a taurine deficiency (in mice) had a shift of metabolism toward the glycolytic pathway, especially in condition of exercise; this has been related to a dysfunction in mitochondrial function and in fatty acid oxidative pathways (the inability to oxidize fatty acids). (25) This leads to mitochondrial damage. Inhibiting fatty acid oxidation (such as with a taurine deficiency) during exercise can lead to a reduction in exercise performance.
8) As taurine is a natural osmolyte, it increases the cells’ hydration. Hydrated cells are the perfect state for muscle growth as dehydrated cells are catabolic.
9) Taurine reduces lactate levels as well as the enzymes’ activity that produces lactate, namely lactate dehydrogenase. (26) Lactate produces fatigue so less lactate can lead to greater endurance.
10) Taurine is also shown to increase protein utilization, as excess protein gets converted to ammonia, creatinine, BUN, etc… Supplemental taurine reduces these markers, which indicate better protein utilization by the body. (27)
11) Taurine supplementation is also confirmed to increase growth hormone significantly in epileptic patients, from 3.0 ng/mL to 17.1 ng/mL after 2 weeks. (29) However, 5g taurine was unable to increase GH in normal men. This could be that a build-up period is required to increase GH.
Dosing and supplement suggestions
Taking taurine with caffeine, before bed or pre-workout would be the best times to do so. Just keep your body saturated with taurine, and that will ensure optimal tissue taurine levels during the day as well as during exercise.
Ingesting lots of taurine for a long period of time will decrease taurine transporters and this will decrease taurine transport into muscles, and the kidneys will also increase taurine excretion.
I think a loading phase with 15g taurine daily for a month would be optimal, as tissue taurine can stay saturated for up to 3 months thereafter. If you don’t want to do a taurine loading phase, taking 250mg to 2g daily will be more than enough for it’s other benefits.