Friday, May 8, 2015

0.3g/kg BW NaHCO3 Power Up Your Most Intense Workouts by Helping You to Maintain Maximal Muscle Activation

Planning to fry your legs? Ingest 0.3g/kg sodium bicarbonate before your workout!
It has long been speculated that the increased concentration of protons /H+) during fatiguing exercise may contribute to increased activation of group III and IV afferents and subsequently reduced central drive. Surprisingly, though, the significance of this process has still to be confirmed in exercising humans.

In a recent study, Jason C. Siegler nd Paul Marshall from the School of Science and Health at the University of Western Sydney determined whether inducing metabolic alkalosis differentially affects descending central drive after fatiguing exercise and whether this effect may, in part, be explained by attenuating group III and IV afferent firing.
You can learn more about bicarbonate and pH-buffers at the SuppVersity

The Hazards of Acidosis

Build Bigger Legs W/ Bicarbonate

HIIT it Hard W/ NaCHO3

Creatine + BA = Perfect Match

Bicarb Buffers Creatine

Beta Alanine Fails to HIIT Back
In the corresponding experiment eleven recreationally active, young, male subjects performed a maximal 2 min voluntary knee extension (MVC) followed by a 2 min rest and subsequent 1 min MVC with an occlusive cuff either in placebo [PLA; 0.3 g/kg body weight calcium carbonate] or alkalosis conditions [ALK; 0.3 g/kg body weight sodium bicarbonate].
"At each of the two experimental sessions, a pre-exercise standardized beverage consisting of 0.3 g/kg BW of 60% maltodextrin and 40% protein (casein and whey) was consumed 1 h before commencing the ingestion protocol [...] After 1 h quiet rest, participants consumed the first of three equally divided doses of either PLA- or ALK-filled gelatin capsules. Capsules were consumed at −90, −60 and −30 min before the exercise protocol" (Siegler. 2015).
For those of you who are having trouble with bicarbonate and diarrhea or general gastro-intestinal distress it may be interesting to know that Siegler et al. have found in previous studies that the preload with the CHO + PRO beverage minimizes the potential for subjects to experience the negative side-effects often associated with ingesting NaHCO3 (Siegler. 2010).
Base excess after ingestion of different amounts of NaHCO3 = sodium bicarbonate (Siegler. 2010)
Gastrointestinal distress? Avoidable! With the CHO + protein preload and 3x 0.1g/kg body weight allotements ingested -90, -60 and -30 minutes before the workout the risk of developing gastrointestinal symptoms will be significantly reduced (Siegler. 2010). As the data on the left-hand side shows a single ingestion of 0.1g/kg NaHCO will yet not be sufficient to markedly increase the base excess in the blood. The data from Siegler 2011 does yet also show that there is still an increase in base excess that may have significant metabolic and health effects including the restoration of GH release and the other stuff I discussed here.

Ah, there's something else I wan to address: Let's also take a look at the stupid non-alternatives out there. Beta-alanine is no alkalizer. It works (if at all) in the cell and may have additive effects, but cannot replace sodium bicarbonate. What is even more stupid, though, is to suggest using calcium carbonate instead. Don't laugh, I've seen "experts" suggest that, because "it's healthier than sodium!" First of all, it's not healthier. Second of all, it's not working AT ALL. In fact it is used as placebo in sodium bicarbonate studies like the one at hand. Ah, and speaking of stupid non-functional replacements. If you want to decrease your performance, go ahead and use potassium carbonate instead. The exuberant increase in serum potassium from supplementation and exercise which will increase the eflux of potassium from the cell into the blood (Medbø. 1990) may eventually impair not increase your performance (Lindinger. 1995). So goddamn, forget about the myth of the bad sodium and stick to what works: Sodium bicarbonate, the only form of sodium that has proven hypotensive (=blood pressure lowering) effects (Luft. 1990).
For the same reason the caspules with the ~24grams of NaHCO3 were ingested in 0.1g/kg allotments -90, -60 and -30 minutes before the workout.
"The actual exercise protocol was performed on an isokinetic dynamometer (KinCom 125, version 5.32, Chattanooga, TN, USA). Participants were seated with their hip and leg flexed to 90 deg, the centre of rotation of the lever arm was carefully aligned with the sagittal plane axis of the knee joint, the lever arm of the dynamometer was firmly attached 2–3 cm superior to the lateral malleolus, and the participant was firmly strapped into the chair with straps across the trunk. [...]  Before the exercise protocol, participants performed a series of submaximal isometric knee-extension efforts (25, 50 and 75% of perceived maximal effort). Six MVCs [maximal voluntare contractions] were then performed in a random order (two with stimulation applied, two with cuff and stimulation applied, and two with no additional measures performed), with 2 min rest between efforts. Each MVC was required to be as fast and forceful as possible and maintained for 3–4 s" (Siegler. 2015).
The results of the extensive tests Siegler and Marshall conducted were unambiguous: While the voluntary activation declined to a similar extent after the 2 min MVC, the voluntary activation during the ischaemic period, i.e. during a period of reduced oxygen availability as it may occur towards the end of a long, intense workout, the voluntary activation was higher during the sodium bicarbonate aka ALK (PLA, 57 ± 8%; ALK, 76 ± 5%) trial.
Figure 1: Single-subject representation of maximal voluntary torque (MVC), superimposed twitch amplitude (SIT; Strojnik & Komi, 1998) and resting twitch amplitude (RT) (left) and voluntary activation (expressed as a percentage) for PLA and ALK at the start of exercise (BASE) and end of the 2 min MVC (120 s), the 2 min ischaemic period (140, 180 and 220 s, respectively) and the end of the experimental trial (300 s) (right | Siegler. 2015).
Similarly, the maximal rate of torque development was significantly higher in the ALK conditions after the 2 min MVC (mean difference of 177 ± 60 N m s−1).
I know what you are about to ask and the answer is easy: Yes, bicarbonate is not only beneficial for endurance athletes and sprinters, it is also highly beneficial for people who lift weight - 25g of Baking Soda (NaHCO3) Will Increase Your Squat (+27%) & Bench Press (+6%) Performance Within 60 Minutes | read the full article.
Overall, the study at hand does therefore demonstrate the effect of pH on voluntary activation as well as maximal rates of torque development after sustained, maximal voluntary knee extension in mans.

The original question, i.e. whether the NaHCO3 induced metabolic alkalosis affects central and peripheral mechanisms associated with exercise-induced muscle fatigue in humans can therefore be answered in the affirmative. Or, as Siegler et al. phrase it "Inducing metabolic alkalosis before exercise preserved voluntary activation, but not muscle excitation, after a 2 min maximal voluntary contraction (MVC) followed by ischaemia. An effect of pH was also observed in maximal rates of torque development, where alkalosis mitigated the reduction in maximal rates of torque development after the initial 2 min MVC" (Siegler. 2015) | Comment on Facebook!
References:
  • Luft, Friedrich C., et al. "Sodium bicarbonate and sodium chloride: effects on blood pressure and electrolyte homeostasis in normal and hypertensive man." Journal of hypertension 8.7 (1990): 663-670.
  • Medbø, J. I., and O. M. Sejersted. "Plasma potassium changes with high intensity exercise." The Journal of Physiology 421.1 (1990): 105-122.
  • Lindinger, Michael I. "Potassium regulation during exercise and recovery in humans: implications for skeletal and cardiac muscle." Journal of molecular and cellular cardiology 27.4 (1995): 1011-1022.
  • Siegler, Jason C., et al. "Effects of various sodium bicarbonate loading protocols on the time-dependent extracellular buffering profile." The Journal of Strength & Conditioning Research 24.9 (2010): 2551-2557.
  • Siegler, Jason C., and Paul Marshall. "The effect of metabolic alkalosis on central and peripheral mechanisms associated with exercise induced muscle fatigue in humans." Experimental physiology (2015).