Friday, September 27, 2013

Rats "On" Taurine Can't Ever Get Enough... Exercise of Course! What Were You Thinking About? Mice Cover 50% More Distance W/ HED of 3-4G of Taurine Post Workout

On Taurine? If she was, she could run another marathon 6h later ;-)
Actually, the results a group of researchers report in a recent paper in the Journal of Sports Medicine and Physical Fitness are a bit surprising. After all, taurine is - as you all should know by now - a GABA agonist and should thus rather have had a calming effect on the mice, the scientists used in their experiment. What Yumiko Takahashi, Eiki Urushibata and Hideo Hatta from the Department of Sports Sciences at the University of Tokyo observed when they supplied their lab animals with 0.5 mg/g body weight immediately after they had them run on a treadmill at 25m/min for 90 min was yet quite the opposite of the laziness you would expect after having read about the calming and balancing effects of taurine Mure et al. (2003) observed, when they administered it either alone or in conjunction with caffeine (read pervious SuppVersity article).

Mice on taurine run more, because they can!?

Contrary to the saline-group in which the exhausting bout of exercise lead to a significant decrease in the amount of voluntary wheel running (compared to the non-exercised mice in the control group; p < 0.01), the rodents who had received a human equivalent of 3-4g taurine (that's what a human would have to take) did not exhibit any signs of exercise induced fatigue. On the contrary:
"Significant effects of post-exercise taurine administration on voluntary wheel running during 6 h were found (p < 0.05). The 30-min running distance was significantly higher in the taurine-treated group than in the saline-treated group at 1-1.5 h after treadmill exercise (p < 0.05)." (Takahashi. 2013)
This increase in voluntary endurance training occurred irrespective of similar blood glucose and liver and skeletal muscle glycogen concentrations in both, the supplemented and placebo treated rodents after the treadmill exercise.
Figure 1: Total running distance and running distance per food ingestion (left); liver and muscle glycogen content (right) at different time points before (baseline) immediately after 0 and 3-6h after the forced 90 min run (Takahashi. 2013)
The total food consumption during 6 h of voluntary wheel running was likewise identical, or as the scientists wrote, it "showed no difference between the two groups". This means that the ratio of total running distance to total food consumption was significantly higher in the taurine treated group - a clear advantage for anyone who wants to burn a few additional calories on the treadmill (you should yet always remember that 90% of the weight loss happens in the kitchen, i.e. by dieting, and "training to burn energy", only, is nothing but stupid!)

Now this clearly raises the question "what's going on here?"

SuppVersity Suggested Read: "Taurine Pumps Up Strength & Recovery in Response to Eccentric Curls. NAC Decreases Peformance & Boosts Fat Oxidation!?" | read more
Obviously you and me are not the only ones who are asking themselves this important question. What is it that makes the post-workout so effective? Actually the mere fact that taurine is effective, when it is administered after a workout and not chronic or pre-workout as in the majority of previous studies is already news.

Well, the scientists seem to believe that the effects must be directly mediated by improved post-exercise recovery. With identical blood, liver and skeletal muscle glucose, we do however have to discard the beneficial effects of taurine on glucose metabolism and a potentially faster restoration of muscle glycogen as a potential explanation (click here to learn more about taurine's beneficial effects on glucose metabolism) .

As Takahashi et al. point out, skeletal muscle loses various ions and other solutes including taurine during exercise to compensate for increases in many osmotically active molecules as a result of enhanced energy metabolism (Usher-Smith. 2009). They go on to explain that
"the restoration of [taurine] may no have direct beneficial effects on the contractile properties of skeletal muscle, including the release and uptake of Ca2+ by the sarcoplasmic reticulum in the excitation-contraction coupling process,  prevention of peroxidation of plasma membranes, and recovery from exercise-induced cellular membrane damage." (Takahashi. 2013)
Accordingly, rodents with a knockout of the taurine transporter (which means these rodents could not use the taurine) showed both reduced taurine concentration in skeletal  muscles and tissues and significantly lower endurance capacity (>80%) compared to wild-type mice.

Taurine could also help fatty oxidation; after all, a recent study by Piña-Zentella et al. observed that taurine treatment increased the catalytic activity of cAMP-activated protein kinase A in white adipocyte tissue cells (Piña-Zentella. 2012).
With this kinase being important for the activation of the lipolitic enzyme cascade in both adipocytes and skeletal muscle.
This may not just help you burn off more fat, but also provide you with the fuel you need during prolonged exercise.
Bottom line: While we still do not know for sure, if it is the increase / faster recovery of cellular osmolality or other aspects of skeletal muscle recovery that are promoted by the post-workout ingestion of 3-4g of taurine (that's what a human would take), the real world results in the study at hand appear to suggest that the usage of an amino acid most trainees usually think of as part of a pre-workout formula may make just as much, if not more sense after a workout. This is particularly true, if you are one of the many trainees who can't wait till he or she gets back to the gym.

In conjunction with the recently covered beneficial effects on insulin sensitivity and think of the importance of the latter with respect to the replenishment of glycogen stores, and the triggering of p-Akt and the nutrient-based increase in protein synthesis, it would therefore appear to make sense to get yourself a 250-500g bag of (dirt cheap) bulk taurine and start experimenting with it. As stated before, the effective dose in the study was 3-4g and the insulin sensitizing effects have been observed with dosages in the 6g range (spread evenly across the meals).

Don't go overboard, though, in susceptible individuals the chronic ingestion of high(er) amounts taurine could trigger an increase in anxiety and that despite the fact that it is actually an anxiolytic (=reduces anxiety; cf. Kong. 2006).

  • Kong WX, Chen SW, Li YL, Zhang YJ, Wang R, Min L, Mi X. Effects of taurine on rat behaviors in three anxiety models. Pharmacol Biochem Behav. 2006 Feb;83(2):271-6.
  • Piña-Zentella G, de la Rosa-Cuevas G, Vázquez-Meza H, Piña E, de Piña MZ. Taurine in adipocytes prevents insulin-mediated H2O2 generation and activates Pka and lipolysis. Amino Acids. 2012 May;42(5):1927-35.
  • Usher-Smith JA, Huang CL, Fraser JA. Control of cell volume in skeletal muscle. Biol Rev Camb Philos Soc. 2009 Feb;84(1):143-59.