Food and Nutrition Sciences, 2010, 1, 1-4
doi:10.4236/fns.2010.11001 Published Online July 2010 (http://www.SciRP.org/journal/fns)
1
Sodium Bicarbonate—A Potent Ergogenic Aid?
Jose Shelton1, Gideon V. Praveen Kumar²
1Victoria University, Melbourne, Australia; 2School of Biosciences and Technology, VIT University, Vellore, India.
Received May 30th, 2010; revised July 4th, 2010; accepted July 7th, 2010.
ABSTRACT
This report aims to look at the role of Sodium bicarbonate as a potent Ergogenic aid and its role in improving the per-
formance of athletes. It includes the mechanism of action of sodium bicarbonate during high-intensity exercise. The
report also shows the various types of athletes who can be benefited from sodium bicarbonate loading, evidences for
improvement in performance, conflicting evidences, recommended dosages and side-effects for bicarbonate loading.
Keywords: Sodium Bicarbonate, Ergogenic Aid, High-Intensity Exercise, Anaerobic Glycolytic System
1. Introduction
An ergogenic aid is defined as any substance, food,
chemical, or training method that helps the body work
harder and perform better. Ergogenic aids are any
external influences that can positively affect physical or
mental performance [1]. These include mechanical aids,
pharmacological aids, physiological aids, nutritional aids,
and psychological aids. Athletes at all levels of competi-
tions are constantly striving for a means to obtain a lead-
ing edge over their opponents and many of them use er-
gogenic aids to improve their energy and performance [2].
Ergogenic aids may directly influence the physiological
capacity of a particular body system thereby improving
performance, remove psychological constraints which
impact performance, and increase the speed of recovery
from training and competition [3].
The term Ergogenic means “to produce work”. Nutri-
tional ergogenic aids are dietary manipulations that can
increase physical power or energy production, enhance
mental strength, or provide a mechanical edge and there-
by improve sport performance [4]. Dietary manipulations
encompass 3 major efforts: alteration of food choices,
addition of macronutrients for specific uses in sports and
exercise, addition of micronutrients for specific uses in
sports and exercise [3].
2. Energy System for High-Intensity
Exercise
Of the 3 primary energy pathways, the anaerobic glyco-
lytic system provides fuel sources, primarily carbohy-
drates, for high-intensity exercises (exercises lasting be-
tween 20 seconds up to about 90 seconds). Anaerobic
glycolysis provides the primary fuel source for exercise
of near-maximal intensity lasting longer than about 30
seconds. High-intensity exercises (anaerobic work) in-
volve the breakdown of carbohydrates (muscle glycogen).
As the glycogen stores are rapidly depleted, there is a
resulting increase in hydrogen ion (H+) concentrations
and lactic acid in both the muscle and blood. It is this
increase in H+ concentration (drop in pH) that causes a
progressive increase in the acidity of the muscle cells
(intracellular environment). The increase in H+ produces,
among other reactions, an inhibition of calcium release
from the sarcoplasmic reticulum and an inhibition of the
interaction between actin and myosin [5]. The drop in pH
as a result of lactic acid accumulation is thought to in-
hibit the resynthesis of adenosine triphosphate (ATP) as
well as inhibit muscle contraction. This in turn results in
muscular fatigue defined as a decrease in force produc-
tion in the presence of increased perception of effort and
an inability to maintain high exercise intensities [6,7].
3. Sodium Bicarbonate
Sodium bicarbonate or sodium hydrogen carbonate is the
chemical compound with the formula NaHCO3. Sodium
bicarbonate is a white solid that is crystalline but often
appears as a fine powder. It has a slight alkaline taste
resembling that of washing soda (sodium carbonate). It is
a component of the mineral natron and is found dissolved
in many mineral springs. The natural mineral form is
known as nahcolite. It is also produced artificially. Since
it has long been known and is widely used, the salt has
many related names such as baking soda, bread soda,
cooking soda, bicarbonate of soda. Colloquially, its name
is shortened to sodium bicarb.

Sodium Bicarbonate – A Potential Ergonomic Aid? 2
4. Role of Sodium Bicarbonate during
High-Intensity Exercise
During high-intensity exercise, muscles keep up with the
demand for energy by converting some carbohydrate to
lactic acid. A build-up of acid inside the muscle cells is
one of the factors responsible for fatigue. This system’s
total capacity is limited by the progressive increase in
acidity within the muscles caused by the accumulation of
lactate and H+ ions. Increased acidity ultimately inhibits
energy transfer and the ability of the muscles to contract,
leading to a decrease in exercise performance. Reducing
the build-up of acid should reduce fatigue and allow the
athlete to go faster or further. The body’s defences against
an increase in acidity are the bicarbonate “buffers”,
which help to neutralize the acid produced by intense
exercise. The natural bicarbonate supply, part of the
body’s buffering system, provides a rapid first line of
defence against this increased acidity.
5. Acting Mechanism
Sodium bicarbonate is an alkalising agent and therefore
reduces the acidity of the blood (known as a buffering
action). By buffering acidity in the blood, bicarbonate
may be able to draw more of the acid produced within
the muscle cells out into the blood and thus reduce the
level of acidity within the muscle cells themselves. This
in turn could delay the onset of fatigue [8]. Studies [9,10]
have confirmed that increased extracellular pH and
higher bicarbonate raise the H+ and lactic acid efflux
from active muscles. This is due to an increase in the
activity of the Lactic acid/H+ co-transporter, which be-
comes more active as the intracellular/extracellular H+
gradient increases, during contraction as well as during
recovery. It has been suggested that this mechanism
causes a decrease in muscular fatigue, delaying the de-
crease in pH level and leading to a greater contractile
capacity of the muscular tissue involved by means of
enhanced muscle glycolytic ATP production. It has been
proven that all of these metabolic perturbations imply a
shift in muscle metabolism toward anaerobic energy
production, which is especially advantageous during
high-intensity exercise [5].
Taking a sufficient quantity of sodium bicarbonate
(baking soda) before high-intensity event makes the
muscles and blood less acidic during the event and can
enhance physical performance [11].
6. Athletes Benefiting from Sodium
Bicarbonate Loading
Athletes have been practising “soda loading” or “bicar-
bonate loading” for over 70 years in an attempt to delay
the onset of muscular fatigue during prolonged anaerobic
exercise. The specific athletes who might stand to benefit
from bicarb supplementation are those who typically
compete in events that last between 1 and 7 minutes, i.e.
400 m - 1500 m running, 100 m - 400 m swimming,
sprint cycling, kayaking, rowing and canoeing events at
intensities that fall between 80 and 125% of peak maxi-
mal oxygen uptake, and many team sports with their re-
peated nature of high intensity exercise. All these events
stress the anaerobic glycolysis system significantly and
produce a lot of acidity. Sports that are dependent on
repeated anaerobic bursts may also benefit from bicar-
bonate loading [6,8].
7. Evidences for Improvement in
Performance
A study done by McNaughton et al. [9], among moder-
ately trained female athletes, showed significant im-
provement in both work and power output, during high
intensity exercise of 60 second duration. The ingestion of
sodium bicarbonate in the experimental trial had the de-
sired effect of raising blood bicarbonate levels by 60%
above the resting bicarbonate value.
According to Stellingwerff [12], a meta-analysis of 29
studies on the performance effects of sodium bicarbonate,
featuring predominately untrained individuals, found that
bicarbonate supplementation resulted in a performance
effect that was 0.44 standard deviations better than in the
control trial. An improvement of 0.44 of the standard
deviation would bring the 2006 average men’s 800m
Golden League time of 1:46.36 down to 1:45.52, which
is a worthwhile improvement. In summary, most data
suggest that the ingestion of 0.3 g/kg body weight of so-
dium bicarbonate administered in solution approximately
1-2 hours before exercise offers a small, but significant,
effect on middle-distance race performance.
In one study [7] designed to simulate athletic competi-
tion, trained non-elite middle-distance runners performed
a simulated 800 m race. In the alkalotic condition, they
ran almost 3 s faster than in the placebo or control trials.
Another report by Maughn et al. [13] indicated similar
improvements (3-4 s) over a distance of 1500 m in run-
ners who completed simulated races in about 4 min 15s.
Although these effects on performance might appear
small, they are of considerable significance to the athlete,
for whom an improvement of even a fraction of a second
in these events is considered to be a major achievement.
In a study by VanMontfoort et al. [10], ingestion of so-
dium bicarbonate was found to increase the sprint per-
formance in elite male athletes compared to citrate, lac-
tate and chloride ingestion.
Studies by McNaughton et al. [14] have also found
that sodium bicarbonate can be used as an ergogenic aid
to offset the fatigue process in high-intensity, competi-
tive cycle ergometry of 1 hour duration.

Sodium Bicarbonate – A Potential Ergonomic Aid? 3
8. Conflicting Evidence
However, even though many of the studies have shown
that sodium bicarbonate administration modifies the
blood acid-base balance, its effects on performance are
not always positive [5]. For instance, no improvements
have been registered following 90 seconds of maximal
cycle exercise by untrained men [15].
No differences were found between the experimental
or placebo trials in female cyclists pedalling at 95% VO2
max [9]. This suggested that bicarbonate buffering does
not improve performance in female athletes during re-
peated bouts of high intensity exercise.
The reasons for the conflicting effects are not alto-
gether clear, but are at least in part due to variations in
the intensity and duration of the exercise tests used, the
nature of the exercise task, the dosage of bicarbonate
administered and the time delay between bicarbonate
administration and the beginning of the exercise test (i.e.
the amount of metabolic alkalosis induced). Performance
has been monitored over exercise durations ranging from
a few seconds to more than 1 hour, and during continu-
ous, incremental and intermittent dynamic exercise as
well as during sustained isometric contractions [13].
There is no clear pattern of exercise duration between
those studies where a positive effect was observed and
those where no effect was seen. In most studies, a dose of
0.3 g of sodium bicarbonate/kg of body weight has been
used to induce alkalosis, and this has usually been ad-
ministered orally in solution or in capsule form. Such a
dose has usually resulted in an increase of 4-5 mmol.L-1
in the plasma buffer base 2-3 hours after administration,
although the time-course of changes in acid-base status
was not carefully followed in most of these studies [16].
Those studies in which high-intensity and short-term
exercises (less than 2 minutes) were used, and in which
the doses of sodium bicarbonate given were lower than
0.3 g/kg body weight, did not generally produce an en-
hancement of performance, which might be due to the use
of an insufficient dose or due to the short duration of the
effort [5]. Therefore, it has been suggested that exercises
lasting less than 1 minute may not be of sufficient duration
for the glycolytic metabolism to activate completely, in
that the capacity of the intracellular buffer is exceeded and
a positive gradient between the intracellular and extracel-
lular medium is established. The main reason for the lack
in performance improvement may consequently be due
more to the exercise duration than to the doses used.
9. Recommended Dosage
Many studies indicate an effective dose of 300mg of
sodium bicarbonate per kg body weight taken 1-2 hours
prior to short-term maximal, high intensity performance
lasting 60 sec shows 30% improvement in performance
[6,11]. Sodium bicarbonate appears to be safe when
taken in the recommended dose of 140mg/pound of body
weight. For a 150 pound athlete this translates to a dose
of 5 teaspoons of baking soda that provides 21,000mg or
21g of bicarbonate. Safety should not be confused with
side effects. Baking soda should be consumed with
plenty of water, (eg. a litre or more), when taken 1 or 2
hours prior to exercise [4].
10. Side Effects
There are of course potential problems of severe alkalo-
sis associated with the use of increased doses of bicarbo-
nate. Additionally side effects like vomiting, gastrointes-
tinal discomfort, bloating, and diarrhea may occur parti-
cularly if sufficient water is not taken with sodium
bicarbonate. Vomiting and diarrhea are frequently report-
ed as a result of ingestion of even relatively small doses
of bicarbonate, and this may limit any attempt to improve
athletic performance by this method, certainly among
those individuals susceptible to gastrointestinal problems.
There have been reports of athletes using this interven-
tion, which is not prohibited by the rules of the sport,
being unable to compete because of the severity of these
symptoms. Although unpleasant and to some extent
debilitating, these effects are not serious and there are no
long term adverse consequences [17].
11. Acute vs Chronic Loading
Given that some individuals exhibit urgent gastrointesti-
nal distress with bicarbonate, such as vomiting and diar-
rhoea, it is important for athletes to experiment with bi-
carbonate in training that features daily consecutive races,
since much of the gastrointestinal distress seems to occur
after a race (semi-finals), which could limit performance
in any subsequent race (finals) [12].
Studies [18,19] have shown more favourable gastroin-
testinal tolerance effects after chronic multiday bicar-
bonate supplementation as compared to acute pre-exer-
cise single-dose administration. Performance in high-
intensity exercise may be enhanced for a full 2 days after
cessation of chronic bicarbonate supplementation which
might alleviate many of the severe gastrointestinal side-
effects found with acute bicarbonate loading.
Not withstanding these results, more research is need-
ed to show performance efficacy for chronic bicarbonate
ingestion protocols in elite athletes, and to better eluci-
date the dosing and time-course effects between the ces-
sation of dosing and exercise performance testing.
12. Conclusions
In conclusion, there are sufficient data to suggest that
sodium bicarbonate can be used as a nutritional ergogenic
aid or dietary supplement for improving performance in
short term, high intensity exercise, provided it is taken in
the recommended dosage of 300 mg (0.3g)/kilogram

Sodium Bicarbonate – A Potential Ergonomic Aid? 4
body weight. Continued use of bicarbonate may help
athletes become less susceptible to the side effects and
may give even larger improvements in performance.
13. Further Research
Since the time elapsed from the ingestion of bicarbonate
to the beginning of exercise (time of absorption) varies
considerably, until further research can clarify the time
course and cessation of dosing that that can lead to per-
formance enhancement, the individual athlete is advised
to experiment in training to judge their own case. The
athlete needs to discover not only the potential for per-
formance improvement, but also the likelihood of un-
wanted side-effects. Further research is also needed to
find out the longest duration of endurance exercise that
benefits from the use of sodium bicarbonate.
REFERENCES
[1] D. M. Ahrendt, “Ergogenic Aids: Counselling the Ath-
lete,” American Family Physician, Vol. 63, No. 5, 2001,
pp. 913-922.
[2] J. R. Berning and S. N. Steen, “Sports Nutrition for the
90’s: The Health Professional’s Handbook,” Aspen Pub-
lishers, Gaithersburg, 1991.
[3] I. Wolinsky and J. A. Driskell, “Nutritional Ergogenic
Aids,” CRC Press, Boca Raton, 2004.
[4] M. Ryan, “Sports Nutrition for Endurance Athletes,”
Velo Press, Boulder, 2002.
[5] B. Requena, M. Zabala, P. Padial and B. Feriche, “So-
dium Bicarbonate and Sodium Citrate: Ergogenic Aids,”
Journal of Strength and Conditioning Research, Vol. 19,
No. 1, 2005, pp. 213-224.
[6] E. Applegate, “Effective Nutritional Ergogenic Aids,”
International Journal of Sports Nutrition, Vol. 9, No. 2,
1999, pp. 229-239.
[7] R. J. Maughn, L. M. Burke and E. F. Coyle, “Food, Nu-
trition and Sports Performance II–The International Oly-
mpic Committee Consensus on Sports Nutrition,” Rout-
ledge Publishing, Cornwall, 2004.
[8] L. Burke and V. Deakin, “Clinical Sports Nutrition,” 2nd
Edition, McGraw-Hill Book Company, Sydney, 2000, p.
478.
[9] L. R. McNaughton, S. Ford and C. Newbold, “Effect of
Sodium Bicarbonate Ingestion on High Intensity Exercise
in Moderately Trained Women,” Journal of Strength and
Conditioning Research, Vol. 11, No. 2, 1997, pp. 98-102.
[10] M. C. E. VanMontfoort, L. VanDieren, W. G. Hopkins
and J. P. Shearman, “Effects of Ingestion of Bicarbonate,
Citrate, Lactate, and Chloride on Sprint Running,” Medi-
cine and Science in Sports and Exercise, Vol. 36, No. 7,
2004, pp. 1239-1243.
[11] L. R. McNaughton, B. Dalton, J. Tarr and D. Buck, “Neu-
tralize Acid to Enhance Performance,” Sportscience Train-
ing & Technology, 1997. http://www.sportsci.org/train-
tech/buffer/lrm.htm
[12] T. Stellingwerff, M. K. Boit and P. T. Res, “Nutritional
Strategies to Optimize Training and Racing in Middle-
Distance Athletes,” Journal of Sports Sciences, Vol. 25,
No. S1, 2007, pp. S17-S28.
[13] R. J. Maughn, D. S. King and T. Lea, “|Dietary Supple-
ments,” Journal of Sports Sciences, Vol. 22, No. 1, 2004,
pp. 95-113.
[14] L. McNaughton, B. Dalton and G. Palmer, “Sodium Bi-
carbonate can be Used as an Ergogenic Aid in
High-Intensity, Competitive Cycle Ergometry of 1 h Du-
ration,” European Journal of Applied Physiology, Vol. 80,
No. 1, 1999, pp. 64-69.
[15] J. O. Marx, S. E. Gordon, N. H. Vos, B. C. Nindl, A. L.
Gomez, J. S. Volek, J. Pedro, N. Ratamess, R. U. Newton,
D. N. French, M. R. Rubin, K. Hakkinen, J. William and
W. J. Kraemer, “Effect of Alkalosis on Plasma Epineph-
rine Responses to High Intensity Cycle Exercise in Hu-
mans,” European Journal of Applied Physiology, Vol. 87,
No. 1, 2002, pp. 72-77.
[16] R. J. Maughan, “Nutritional Ergogenic Aids and Exercise
Performance,” Nutrition Research Reviews, Vol. 12, No.
2, 1999, pp. 255-280.
[17] R. J. Maughan and L. M. Burke, “Handbook of Sports
Medicine and Science: Sports Nutrition,” Blackwell Pub-
lishing, Cornwall, 2002.
[18] I. I. Douroudos, I. G. Fatouros, V. Gourgoulis, A. Z.
Jamurtas, T. Tsitsios, A. Hatzinikolaou, K. Margonis, K.
Mavromatidis and K. Taxildaris, “Dose-Related Effects
of Prolonged NaHCO3 Ingestion during High-Intensity
Exercise,” Medicine and Science in Sports and Exercise,
Vol. 38, No. 10, 2006, pp. 1746-1753.
[19] J. Edge, D. Bishop and C. Goodman, “Effects of Chronic
NaHCO3 Ingestion during Interval Training on Changes
to Muscle Buffer Capacity, Metabolism, and Short-Term
Endurance Performance,” Journal of Applied Physiology,
Vol. 101, 2006, pp. 918-925.