Influence of an alkalizing supplement on markers of endurance

12 Pages·2012·0.65 MB·English

by  Daniel P Heil

Heiletal.JournaloftheInternationalSocietyofSportsNutrition2012,9:8
http://www.jissn.com/content/9/1/8
RESEARCH ARTICLE Open Access
Influence of an alkalizing supplement on markers
of endurance performance using a double-blind
placebo-controlled design
Daniel P Heil*, Erik A Jacobson and Stephanie M Howe
Abstract
Background: Previous research has shown that ingestion of substances that enhance the body’s hydrogen ion
buffering capacity during high intensity exercise can improve exercise performance. The present study aimed to
determine whether the chronic ingestion of an alkalizing supplement, which purports to enhance both intracellular
and extracellular buffering capacity, could impact cardiorespiratory and performance markers in trained Nordic
skiers.
Methods: Twenty-four skiers (12 men, 12 women), matched for upper body power (UBP), were split into treatment
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and placebo groups. The treatment group ingested Alka-Myte -based alkalizing tablets (1 tablet/22.7 kg body
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mass/day) over seven successive days while the placebo group consumed placebo tablets (i.e., no Alka-Myte ) at
the same dosage. Prior to tablet ingestion (i.e., pre-testing), both groups completed a constant power UBP test,
three successive 10-sec UBP tests, and then a 60-sec UBP test. Next, skiers completed the 7-day ingestion of their
assigned tablets followed immediately by a repeat of the same UBP tests (i.e., post-testing). Neither the skiers nor
the researchers were aware of which tablets were being consumed by either group until after all testing was
complete. Dependent measures for analysis included heart rate (HR), oxygen consumption (VO ), minute ventilation
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(V ), blood lactate (LA), as well as 10-sec (W10, W) and 60-sec (W60, W) UBP. All data were evaluated using a two-
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factor multivariate repeated measures ANOVA with planned contrasts for post-hoc testing (alpha = 0.05).
Results: Post-testing cardiorespiratory (HR, VO , V ) and LA measures for the treatment group tended to be
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significantly lower when measured for both constant power and UBP60 tests, while measures of both 10-sec (W10:
229 to 243 W) and 60-sec UBP (W60: 190 to 198 W) were significantly higher (P < 0.05). In contrast, there were no
significant changes for the placebo group (P > 0.05).
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Conclusions: Following the 7-day loading phase of Alka-Myte -based alkalizing tablets, trained Nordic skiers
experienced significantly lower cardiorespiratory stress, lower blood lactate responses, and higher UBP measures.
Thus, the use of this supplement appeared to impart an ergogenic benefit to the skiers that may be similar to the
effects expected from consuming well-studied extracellular buffering agents such as sodium bicarbonate.
Keywords: Cross country skiing, Upper body power, Oxygen uptake, Buffering capacity
Background supplement. For example, numerous studies have tested
Ergogenic aids are generally described as substances or the efficacy of ingesting sodium bicarbonate or sodium
techniques used to improve athletic performance. Nutri- citrate to enhance intracellular and extracellular buffer-
tion supplements are often evaluated for their potential ing capacity during high intensity exercise [1-3]. Theore-
as ergogenic aides by testing an athlete’s physiological tically, the ingestion of these substances can enhance the
work capacity both before and after consumption of the body’s buffering capacity by absorbing the hydrogen ion
(H+) by-product from intramuscular ATP hydrolysis, as
well as ATP production via sarcoplasmic glycolysis [4].
*Correspondence:[email protected]
MovementScience/HumanPerformanceLab,MontanaStateUniversity, During high intensity non-steady-state exercise, the rate
H&PEComplex,HoseausRoom121,Bozeman,MT59717,USA
©2012Heiletal;licenseeBioMedCentralLtd.ThisisanOpenAccessarticledistributedunderthetermsoftheCreativeCommons
AttributionLicense(http://creativecommons.org/licenses/by/2.0),whichpermitsunrestricteduse,distribution,andreproductionin
anymedium,providedtheoriginalworkisproperlycited.
Heiletal.JournaloftheInternationalSocietyofSportsNutrition2012,9:8 Page2of12
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of H+ ion production exceeds the muscle fiber’s ability Procedures
to buffer and/or remove the H+ ions from the sarco- Thefirstvisitfamiliarizedsubjectswiththetestingproto-
plasm. As a result, both intracellular and extracellular coltobeusedforsubsequentvisits.Dependentmeasures
pH can decrease and subsequently contribute to muscu- recorded duringthe second visit(i.e., pre-testing) served
lar fatigue [5]. Thus, an enhanced buffering capacity has to establish a baseline for both placebo and treatment
the potential to ameliorate the impact of increased H+ groups.Followinga7-daysupplement loadingphase,the
production on muscular work capacity during exercise. same tests were administered and dependent measures
Recently,analkalizing nutritionsupplement,hereafter collectedduringthethirdvisit(i.e.,post-testing)andthen
referredtoasANS(TAMERLaboratories,Inc.,Shorline, compared directly to the pre-test measures. Dependent
WAUSA),hasbeenmarketedtoenduranceathletesasa measures of interest included measures of upper body
meansformaximizingtheirintracellularandextracellular power (UBP), as well as cardiorespiratory and blood lac-
bufferingcapacity via adaily mineral-based supplement. tateresponsestotheUBPtests.
According to the manufacturer, regular consumption of During the first visit, subjects read and signed an
this product will supplement the body’s ability to buffer informed consent document approved by the Montana
excess hydrogen ions resulting from metabolic acidosis State University Internal Review Board (IRB). Subjects
during high intensity exercise.Asa result,the manufac- thenpracticedwiththetestingprotocolstobeusedduring
turerclaimsthatuserscanexpecttoexperienceincreased theirsecond(pre-testing)andthird(post-testing)visitsto
time tofatigue,lower bloodlactate levelsduringsteady- thelab.Duringthelattertwovisits,subjectscompleteda
stateexercise,aswellasamorerapidrecoveryofmuscu- submaximaldoublepolingtest(i.e.,Constant-PowerTest),
lar strength following an intense muscular effort. The followed by three trials of a maximal intensity 10-sec
supplementcomesintablet form,isconsumed atadose upperbodypowertest(UBP10),andthenfinishedwitha
relativetobodymass(1tabletper22.7kg),andcontains highintensity60-secUBPtest(UBP60).Anoutlineofthe
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aproprietaryblendofingredientscalledAlka-Myte .All test protocoladministered forbothpre-andpost-testing
oftheANSingredientsareallowedby boththe U.S.and isoutlinedinFigure1.Thethirdlabvisit(i.e.,post-testing)
World anti-doping agencies (i.e., WADA), while Alka- occurred within 24 hrs of completing the supplement
®
Myte itself has been granted New Dietary Ingredient loading phase and repeated all test measures performed
(NDI)recognitionbytheFoodandDrugAdministration duringthesecondlabvisit(Figure1).Thefirstvisitlasted
(FDA). approximately30minutes,whiletheothertwovisitslasted
Given the clearance by WADA and the FDA’s NDI 60minuteseach.
recognition,itsurprisingthattherearenopublishedcon- Priortotheirpre-testingarrival,subjectswererandomly
trolledstudiestoevaluatetheefficacyoftheperformance- assigned into one of two groups, placebo and treatment,
relatedclaimsstatedearlier.Therefore,thepurposeofthis after being matched for their single highest W10 value
study was to investigate the potential influence of this fromthefirstvisitUBP10tests.Forexample,thetwosub-
alkalizing nutrition supplement on previously validated jects with the highest UBP10 values were randomly
correlatesofcross-countryskiingperformance(i.e.,upper assigned into the placebo and treatment groups, while
body power) [6], as well as cardiorespiratory and blood subsequently ranked pairs were similarly assigned. This
lactateresponsesinwell-trainedcompetitiveNordicskiers group assignment strategy was designed to place skiers
bothbeforeandaftera7-dayloadingperiod. with similar caliber of UBP within each test group. The
treatment group would consume the ANS tablets while
Methods theplacebogroupwouldconsumeplacebotabletsduring
Subjects and study design the 7-day loading phase. The ANS tablet manufacturer
Competitive Nordic skiers from the surrounding area was able to provide both ANS and placebo tablets (see
were recruited to visit the Movement Science/Human description below) in sealed packages corresponding to
Performance Labonthe Montana State University cam- the two groups such that neither the subjects nor the
pus on three separate occasions. Competitive skiers investigatorsknewtheidentityofeithergroup.
familiar with the test protocols used for this study were
recruited to help minimize changes expected with ath- Constant-power test
letesperforminglab-basedperformancetestsforthefirst After a 5-minute warm-up on the double poling erg-
time. All subjects wereassignedintoa treatment or pla- ometer at a self-selected power output, subjects were fit
cebogroup,butneitherthesubjectsnortheinvestigators withthemetabolicmeasuringequipmentandbegandou-
were aware of the either group’s identity until after all ble poling at a power output equivalent to 50% of the
datacollectionwascomplete(i.e.,double-blindplacebo- value derived from the UBP10 test (W10, W; from first
controlleddesign). visit). Using a constant poling cadence, the goal was to
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Figure1Diagramoftimelinefortestingprotocol.Thetoprowshowstheorderofupperbodypower(UBP)testsandrestintervals(RI),as
wellasthetotaltimeaccumulated(inparentheses)withineachmeasurementperiod.Thesecondrowshowstheapproximatetimesatwhich
eightseparatefingertipbloodlactatesampleswerecollected(indicatedsequentiallyasL1-L8).Arrowswithinthissamerowpointtowardthe
timeperiodatwhichthetestactuallyoccurred(shownasdarkenedboxeswithinthirdrow).Timeswithinparenthesesinthethirdrowindicate
actualRItimefollowingeachtest.
reach a plateau inheart rate (HR)and oxygenconsump- Previousresearchinourlab hasdeterminedthat mea-
tion(VO )withinthreeminutes.Theconstant-powertest sures of both W10 and W60 correlate highly (r ≥ 0.92)
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continuedfor5-minsatwhichtimethepolingstoppedto with10kmclassical Nordicski race performance[6].At
draw a fingertip blood sample for the determination of 10 seconds of maximal effort, the UBP10 test was
blood lactate. Two blood lactate samples were drawn at designedtoemphasizeutilizationoftheATP-PCrenergy
approximately 30 and120secondspost-exercise(L1and system,whereastheUBP60testwasdesigned toempha-
L2,respectively;Figure 1). Priorto testing, the constant- sizeuseoftheglycolyticsystem.Thus,thebasisforusing
powertestwasintendedtobeasteady-stateevaluationof the W10 and W60 measures within the current study is
double-poling economy, but the ergometer load (50% of the supposition that any factor, such as a nutrition sup-
W10) was too high for all subjects to maintain a steady- plement, that can influence measures of W10 and/or
stateoverfivemins.Thus,thetestisreferredtoasacon- W60couldpotentiallyinfluenceactualNordicskiracing
stant-power test rather than a test of double-poling performanceaswell.
economy. Additional research in our lab has established reliabil-
ity characteristics for the W10 and W60 measures (i.e.,
UBP Testing day-to-day repeatability). A local group of competitive
Immediately following the constant-power test, subjects Nordic skiers, each with 3+ years of ski racing experi-
rested for three minutes before performing three conse- ence, participated in two UBP testing visits in our lab
cutive trials of the UBP10 test. The 10-second test pro- within 24 hours to two weeks of each other. During
tocol is imbedded within a 30-second time period where each test visit, the UBP10 and UBP60 tests were admi-
the skier spends the first 20 seconds ramping up power nistered exactly as described for the present study. Spe-
output and poling cadence before exerting a maximal cifically, three UBP10 tests were followed by a single
double poling effort the final 10 seconds. The average UBP60 test with a fixed amount of rest between tests.
power output measured by the ergometer during the Subjects who had never performed these tests prior to
final 10 seconds is recorded as the 10-second UBP the reliability study returned for a third visit (i.e., first
(W10, W). Each 30-sec test period was followed by 2.5 visit data were not used for data analysis). Mean values
mins of rest prior to beginning the next 30-sec UBP10 for W10 and W60 across the first (Mean ± SE: 208 ± 21
test period. Subjects used the first trial as an additional W and 164 ± 16 W, respectively) and the second tests
warm-up, using approximately 80% of maximal effort (210 ± 22 W and 162 ± 16 W, respectively) did not dif-
during the last 10 seconds, before giving 100% effort for fer significantly (P = 0.55 and 0.39, respectively). In
the final two trials. Next, subjects rested again for an addition, intraclass correlations, whether computed
additional 2.5 mins before performing a single 60-sec across two days of testing (ICC > 0.99) or extrapolated
test during which the goal was to achieve the highest for a single measurement (ICC > 0.98), were high, while
average power output over the entire 60 seconds (W60, the standard errors of measurement for both W10 (±
W) when starting from a dead stop. Thus, dependent 2.7 W) and W60 (± 2.0 W) were low. Collectively, these
measures of UBP from these tests included both W10 data indicate that the UBP10 and UBP60 test variables
(best of the last two of three trials) and W60 (one trial were reliable when using trained Nordic skiers familiar
only). During the UBP testing, the metabolic measure- with the test protocols.
ment system was continuously measuring both HR and
VO , while recovery measures of fingertip blood lactate Nutrition supplement
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were measured at 30 and 120 secs immediate post-exer- The treatment group consumed ANS tablets at the pre-
cise into each rest interval. scribed dosage of 1 tablet per 22.7 kg (i.e., 50 lbs) of
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body mass per day, with half to two-thirds of the dosage visit was recorded and used for testing during each sub-
consumed in the morning and the remainder at night sequent visit.
before going to bed. The ANS tablets are considered a Indirect calorimetry
mineral supplement with each tablet containing calcium Based upon unreported pilot testing prior to this study,
(225 mg), magnesium (1 mg), potassium (36 mg), in a we speculated that one or more cardiorespiratory para-
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proprietary blend of ingredients called Alka-Myte meterscouldbeinfluencedbyANSiftherewasasubse-
(1000 mg). According to the manufacturer, there have quentinfluence onmeasuresofUBP. Thus, measuresof
been no significant adverse events reported to acute or oxygen consumption (VO , L/min), minute ventilation
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chronic consumption of this supplement. The placebo (V ,L/min),andheartrate(BPM)wereincorporatedinto
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tablets were formulated by the ANS manufacturer to theprotocol.Using standardindirectcalorimetry proce-
have a similar size, color, shape, and texture as the ANS dures, a portable metabolic system (Oxycon Mobile,
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tablets while lacking the Alka-Myte active ingredient. Viasys Healthcare, Yorba Linda, CA) was worn by each
Those subjects assigned to the placebo group consumed subjectusingamodifiedhydrationbackpack(Slipstream;
a placebo tablet (maltodextrin-based) in the same dose Camelbak Products, LLC; Petaluma, CA). The oxygen
(1 tablet/22.7 kg body mass/day), frequency (split over and carbon dioxide analyzers were calibrated prior to
morning and evening), and duration (7 day ingestion eachtestusingacertifiedgasmixture.Bothanalyzers,as
period) as prescribed for the treatment groups’ con- well as the ventilation meter, were calibrated prior to
sumption of ANS tablets. eachtestaccordingtothemanufacturer’sguidelines.The
metabolic system collected breath-by-breath data which
Instrumentation was then reported as 60-sec (for the Constant-Power
UBP Ergometer Test) and 5-sec sample intervals (UBP10 and UBP60
A modified Concept 2 rowing ergometer (Concept 2 tests) for both VO and V . Using a Polar Accurex Plus
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Model D; Morrisville, VT, USA), similar to that heart rate monitor strap (Polar Electro, Inc., Lake Suc-
described by Nilsson et al. [7], was used for all UBP cess, NY), the metabolic system also collected and
testing in this study. In place of the sliding seat on a reportedheartrate(BPM)dataoverthesame60-and5-
typical Concept 2 ergometer, a resistance-loaded trolley sec intervals. During testing, the raw data signals from
is connected to the chain that turned the air-braked fly- the metabolicsystem,includingthatforHR,were trans-
wheel. Two cross-country ski poles are attached to the mitted via telemetry to a computer base station within
trolley such that pushing on the poles slides the trolley 20 meters of the UBP ergometer (telemetry range is <
backward along the rail. The chain, in turn, spins the 1000meters).
ergometer’s flywheel which thus provides resistance Blood lactate analyzer
each time the poles are pushed backward. As the poles Using the handheld Lactate Pro analyzer (Arkray, Inc.,
are brought back forward during the recovery phase, the Kyoto, Japan), whole blood lactate from a single finger-
trolley is pulled forward by the pole tips along the rail tip blood droplet is analyzed in 60 seconds. The reagent
with very little resistance. Additional ergometer modifi- test strip for the meter requires 5 μl of whole blood,
cations included a longer steel rail than a typical rowing sampled by capillary action, to initiate an internal che-
ergometer (2.8 m instead of 1.4 m), as well as a platform mical reaction and subsequent electrical current propor-
mounted above and to the front of the rail on which the tional to the lactate concentration. Previous research has
skier stands during testing. Identical to the Concept 2 shown that while correlations between blood lactate
ergometer, the modified ergometer provides a continu- values from different analyzers using the same blood
ous digital display of power output in watts (using the sample can be high (r ≥ 0.97), the absolute difference
Concept 2 PM3 digital monitor), as well as a recording between monitors can be practically meaningful (± 2-3
of average power output over user-defined work periods. mM) over the physiological range of 1-18 mM). To help
Previous research has reported the test-retest of power control for known confounders to the measurement of
measurements using the Concept 2 ergometer to have blood lactate for this study, several precautions were
been reliable in tests lasting 90 to 420 seconds [8]. The taken. First, the monitor’s Check Strip (allows a self-
ski poles used for ergometer testing (Toko P232 poles; check by the monitor) and Calibration Strip (comes
Mammut Sports Group AG, Seon, Switzerland; Swix with each box of reagent strips) was utilized prior to
synthetic cork grips and Swix Pro Fit straps; Swix Sport each test session. Second, it is known that lactate con-
USA Inc., Boston, MA), available in 5-centimeter incre- centrations can vary between boxes of test strips for the
ments between 135 cm and 170 cm, were fit to within same blood sample. To help control for this variability,
2.5 cm of each subject’s own classic racing pole length. a single box of test strips was assigned to each subject
The length of poles used by each subject during the first for both pre- and post-testing lactate measures. Third,
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fingertip sampling for blood lactate can be highly vari- the placebo or ANS tablets. Subjects were instructed to
able due to inconsistent skin cleaning and sampling pro- considerunusualorunexpectedgastrointestinal(GI)dis-
cedures. Lastly, it is possible for individual Lactate Pro tress(e.g.,stomachachingorcramping,excessgas),orany
meters to provide slightly variable lactate measures for other unusual physiological sensations, as possible side
the same blood sample. These last two factors were effects.
mitigated with standard measurement protocols, using
the same researcher for all lactate testing and by using Statistical analyses
the same meter for each subject for both pre- and post- Summarymeasuresofpoweroutput(W10,W60),cardior-
testing. Given the controls mentioned above, Pyne et al. espiratorymeasuresfromtheconstant-powertest(60-sec
[9] concluded that “the Lactate Pro is accurate, reliable HR, VO , V ), peak cardiorespiratory measures fromthe
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and exhibits a high degree of agreement with other lac- UBP10 and UBP60 tests (5-sec HR, VO , V ), as well as
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tate analyzers”. recovery blood lactate measures following each test (L1-
Diet and exercise log L8)wereevaluatedusingmultivariatetwo-factor(group×
Bothdiet and recent exercise habitscouldconfound the time) repeated measures analysis of variance (ANOVA).
measures of UBP, as well as the cardiorespiratory and Post-hoctestingwasperformedusingplannedcontraststo
bloodlactate responsesby influencingintracellularand/ compare pre-testing and post-testing values within
orextracellularbufferingcapacity.Toaddressthisissue, placebo and treatment groups (alpha = 0.05). Using the
weattemptedtocontrolthesefactorswithineachsubject proceduresdescribedbyCohen[10]andtheUBPreliabil-
ratherthanacrossallsubjects.Usingasimple2-pagediet ityreportedbypreviously[6],asamplesizeof10-12sub-
andexerciselog,subjectsrecordedthegeneraltypesand jectspergroupwereneededtodetectameandifferenceof
amounts of food consumed during the 48 hrs preceding 10-15W(Power=0.80andalpha=0.05).
testing. Subjects also used the log to record the types of
exercise(mode,intensity,duration)inwhichtheypartici- Results
pated during the same time period. Subjects were asked Atotalof26subjectswererecruitedbutonly24wereable
torefrainfromhighintensityandlongdurationactivities tocompleteallthreelabvisits.Thedemographicsforthe
forthe24hrsprecedingbothpre-andpost-testing.After remaining 24 subjects (12 per group), summarized in
anevaluation of the log by researchers at the end of the Table1showanequalrepresentationofmenandwomen.
pre-testingvisit,subjectskeptthelogsforreferencedur- This latter characteristic of the two groups was not
ingthe48hrspriortothepost-testingvisit.Ideally,sub- plannedapriori,butrathertheresultoftheW10matching
jects were to use the 2-page log as a reference so that and splitting strategy. All subjects had been Nordic ski
theirdietandactivity habitswere relativelysimilarprior racing between fiveand20 yearswithall butone subject
to pre- and post-testing lab visits. An additional 2-page training and competing in Nordic ski races during the
log was maintained for both diet and exercise for the recentlycompletedskiseason.The2-daydietandexercise
48hrspriortopost-testing.Attheendofthepost-testing logsforbothpre-andpost-testingwerecollectedfromall
visit, the logwas again reviewed by researchersto verify subjects.Accordingthesubjects,theactofrecordingdiet
whatwasrecorded.Analyseswere notperformed onthe and exercise habits prior to pre-testing was useful for
nutrition and exercise log data, but rather used as a monitoring and controlling these behaviors prior to the
method to assist subjects with adhering to the require- post-testingvisit. Lastly, reportsof perceived side effects
mentsofthestudy. wererelativelyminimal.Foursubjectswithin theplacebo
Lastly, subjects were asked to use the 2-day logs as a groupreportedusualGIdisturbances(upsetstomachover
meansforrecordinganyperceivedsideeffectsofingesting 7 days; unusual gas over 2 days) or events (bad taste to
Table 1Descriptive statistics for demographic variables corresponding to placebo andtreatment groups
Group Gender Sample Age BodyHeight BodyMass
Size (years) (cm) (kg)
Placebo Men 7 29±9 178.5±7.8 76.9±8.8
(20-47) (167.1-188.5) (66.1-90.5)
(n=12) Women 5 29±11 167.6±4.6 61.3±8.5
(18-44) (162.4-171.5) (52.4-75.0)
Treatment Men 7 27±12 180.6±9.1 72.7±3.4
(19-52) (169.2-195.0) (68.5-78.2)
(n=12) Women 5 21±3 167.8±4.7 63.7±5.3
(18-26) (163.3-175.1) (57.6-70.7)
NOTE:AllvaluesexpressedasMean±SD(Range)
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capsules; unusual color in urine and feces noted), while Table 3Summaryof60-sec upperbody power(W60)
only one subject in the treatment group noted unusual resultsfor familiarization, pre-testing, andpost-testing
bowelmovementactivitywhileingestingtheANStablets. visits
None of these perceived side effects, however, were Group W60forthe W60for W60for
reported to have limited or changed anything about the Familiarization Pre-Testing Post-Testing
Trial(W) Trial(W) Trial(W)
affectedsubjects’usualdietorexercisehabits.
Placebo 187±24 186±23 188±22
(n=12)
Measures of UBP Treatment 188±22 190±24 †198±25
Mean values for W10 and W60 across test groups and (n=12)
UBP tests (Tables 2 and 3, respectively) show that W60
NOTE:AllvaluesexpressedasMean±SE
valueswereapproximately75-85%oftheW10values, an †Meanpost-testingW60forthetreatmentgroupwassignificantlyhigherthan
observationconsistentwithpreviousW10andW60test- thetreatmentgroups’meanvaluesforfamiliarizationandpre-testing
ing in collegiate Nordic skiers [6]. Mean W10 values for
theplacebogroupwerestatisticallysimilaracrossfamiliar- testingcardiorespiratory variables (HR,VO ,andV )for
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ization, pre-testing, and post-testing trials (241-250 W; the UBP60 test were significantly lower than the group’s
Table2).Similarly,W60fortheplacebogroupdidnotdif- pre-testingvalues.
fer significantly across the three lab visits (186-188 W;
Table 3). In contrast, post-testing values for both W10 Blood lactate measures
(Table2)andW60(Table3)weresignificantlyhigherfor Summary statistics for blood lactate measured at eight
the treatment group relative to familiarization and pre- separate time points (L1-L8) are shown in Table 7. Pre-
testingvalues.Post-testingW10valueswere+14Whigher and post-testing lactate values were statistically similar
thanpre-testingvaluesforthetreatmentgroupcompared for the first seven time points for the placebo group.
with only +4 W higher for the placebo group. Similarly, The placebo group’s post-testing value for the eighth
post-testingW60valueswere+8Whigherthanpre-test- time (L8) point was significantly higher than the pre-
ingvaluesforthetreatmentgroupcomparedwithonly+2 testing value (10.3 ± 0.6 vs 9.7 ± 0.6 mmol/L). Pre- and
W for the placebo group. Figures 2 and 3 illustrate the post-testing values for the treatment group were also
rangeofindividualchangesinW10andW60,respectively, statistically similar for L2-L6, but post-testing values for
frompre-to post-testingforboth placeboandtreatment L1, L7, and L8 were all statistically lower than their cor-
groups. responding pre-testing values.
Cardiorespiratory measures Discussion
Summary statistics formeasures ofHR,VO ,andV are Thepresentstudywasdesignedtoevaluatethepotential
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presentedinTables4,5,6,respectively.Pre-topost-test- influence of an Alka-Myte -based alkalizing nutrition
ing mean HR, VO , and V values for the placebo group supplement (ANS) on cardiorespiratory, blood lactate,
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were statistically similar across the UBP tests. The one andupperbodypower(UBP)measuresintrainedNordic
exceptionwasmeanpost-testingVO fortheUBP60test skiers. Collectively, the results from the constant-power
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which was significantly higher than the placebo group’s andUBP60testssuggestthat,incomparisontoingesting
pre-testingvalue.Similarly,cardiorespiratorymeasuresfor theplacebo,a7-daysupplementloadingperiodimparted
thetreatmentgroupdidnotdifferentsignificantlybetween what could be interpretedas an ergogenic effecton sev-
pre- andpost-testing conditions forallthree trialsofthe eraldependentvariablesfortwoofthe threetestsadmi-
UBP10test.However,post-testingHRandVO wereboth nistered.Forexample,post-testingcardiorespiratory(HR,
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significantly lower than pre-testing values for the treat- VO ,V )andbloodlactatevaluestendedtobelowerfor
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ment group’sconstant-power test.Additionally, all post- bothconstant-powerandUBP60testswhiletheabilityto
Table 2Summaryof10-sec upperbody power(W10)results forfamiliarization, pre-testing, andpost-testing visits
Group BestW10fortheFamiliarization BestW10forthe BestW10forthe
Trial(W) Pre-Testing Post-Testing
Trials(W) Trials(W)
Placebo 241±30 246±31 250±31
(n=12)
Treatment 225±28 229±29 †243±29
(n=12)
NOTE:AllvaluesexpressedasMean±SE.
†Meanpost-testingW10forthetreatmentgroupwassignificantlyhigherthanthetreatmentgroups’meanvaluesforfamiliarizationandpre-testing.
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Figure 2 Individual changes in 10-sec upper body power (Delta W10, W). Thesedata represent measured changes following a 7-day
nutritionsupplementloadingperiod(pre-versuspost-testing)forbothplacebo(A)andtreatment(B)groups.Notethatvaluesformenare
indicatedwithdashedlinesandopensquares(□),womenbydashedlinesandopencircles(○),andchangeinthegroupmeanisindicated
withasolidlineandcloseddiamond(♦).Thehorizontaldottedlineindicatesnochangebetweenpre-andpost-testing.
generate power over 60-seconds (i.e., W60 values) was groups,werethosewiththehighestW10values.Regard-
significantly higher following ANS supplementation. In less, the treatment group’s change from pre-testing to
contrast, results from the UBP10 tests provided a less post-testingforHR (164 to 159BPM),VO (2.84 to2.77
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definitiveergogeniceffectforthetreatmentgroupdespite L/min),bloodlactate(7.0to5.5mmol/L)wereallsignifi-
the fact that the treatment group experienced a signifi- cantly lowerfor the constant-power test whereas signifi-
cantincreaseinW10overtheplacebogroup’slackofsig- cant changes for the placebo group were not observed.
nificantchange. This suggests that the treatment group experienced less
cardiorespiratoryand/ormuscularstresswhiledouble-pol-
Constant-power test ingat thesamemeanpoweroutputfollowingsevendays
The constant-power test involved double-poling on the ofANSsupplementation.
ergometerforfiveminutesatanUBPequivalentto50%of Interestingly,theaboveobservationsaresimilartopre-
W10. This test was originally intended to elicit steady- vious evaluations of the influence of pre-exercise meta-
state cardiorespiratory and blood lactate responses and bolicalkalinizationonVO kinetics[11-13].Forexample,
2
thusprovidemeasuresofmoderate-highintensitydouble- Kolkhorst et al. [12], using pre-exercise sodium bicarbo-
poling economy. In fact, more than half of the subjects nate (NaHCO ) ingestion to induce metabolic alkalosis
3
showed small but steady increases in cardiorespiratory priortohighintensityexercise,foundthattherapidcom-
parameters during the last 2-3 minutes of the test (i.e., ponentofVO kineticswasslowedwhencomparedtothe
2
non-steady-state responses). The subjects most likely to controlcondition.Bergeretal.[11]alsofoundpre-exercise
experience non-steady-state responses to the protocol, NaHCO ingestiontoinfluenceVO kineticsduringhigh
3 2
which were evenly split across placebo and treatment intensity exercise, but they also found that end-exercise
Heiletal.JournaloftheInternationalSocietyofSportsNutrition2012,9:8 Page8of12
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Figure 3 Individual changes in 60-sec upper body power (Delta W60, W). Thesedata represent measured changes following a 7-day
nutritionsupplementloadingperiod(pre-versuspost-testing)forbothplacebo(A)andtreatment(B)groups.Notethatvaluesformenare
indicatedwithdashedlinesandopensquares(□),womenbydashedlinesandopencircles(○),andchangeinthegroupmeanisindicated
withasolidlineandcloseddiamond(♦).Thehorizontaldottedlineindicatesnochangebetweenpre-andpost-testing.
VO wassignificantlylower(2.79versus2.88L/min)atthe Table 5)withaconcomitantdecreasesinHR(164to159
2
end of six minutes of high intensity exercise when com- BPM;Table4)andbloodlactate(7.0to5.5mmol/LforL1;
pared to the control condition. The present study Table7).Thus,whilebloodpHchangeswerenotdirectly
observed a similar decrease in VO (2.84 to 2.77 L/min; monitoredduringthepresentstudy,thecardiorespiratory
2
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Table 4Summaryheart rate(BPM) measures resulting fromfive upper bodypower tests
Group Test Constant UBP10 UBP10 UBP10 UBP60
Period Power Test Test Test Test
Test Trial#1 Trial#2 Trial#3
Placebo Pre-Test 161±4 156±2 167±2 169±2 182±2
(n=12)
Post-Test 160±4 157±3 167±3 169±3 183±2
Treatment Pre-Test 164±6 158±5 165±4 166±4 184±4
(n=12)
Post-Test †159±6 160±6 169±6 167±4 †177±3
NOTE:AllvaluesexpressedasMean±SE;UBP10=10-secupperbodypowertest;UBP60=60-secupperbodypowertest
†Post-testmeasureofheartrateforConstant-PowerandUBP60testsweresignificantlylowerthanpre-testmeasurewithinthetreatmentgroup(P<0.05)
changesobservedwithANSsupplementationwereconsis- testswerenotnecessarilyexpected.However,forthesake
tentwithpriorinvestigationsofNaHCO supplementation of consistency, we chose to administer the UBP10 and
3
onVO kinetics.Thisobservationappearstosupportthe UBP60testsinthesamemannerasthatdescribedforthe
2
claim by the ANS manufacturer that regular use of this original development andvalidation ofthese tests[6]. In
supplementcanenhancemetabolicbufferingcapacityand addition,pilottesting(priortothisstudy)withaprotocol
lower blood lactate responses during high intensity, sub- thatrequiredeightsuccessiveUBP10testswith30-secrest
maximalexercise.Ofcourse,furthertestingshouldbeper- intervals suggested that both peak HR and W10 were
formedtodirectlyevaluatethisclaim. responsivetoa7-dayANSloadingphase.Thus,thechoice
to be consistent withprevioustesting protocols, inaddi-
UBP10 Test tiontothebrevityoftheactualtesttime(10seconds)and
TheUBP10testwasadministeredasthreesuccessivetrials lengthoftotalrest(2.5mins),probablycontributedtothe
with the first serving as a practice and the last two per- lack of meaningful cardiorespiratory or blood lactate
formedmaximally.Followingthe7-dayloadingphase,both changes in the treatment group. A second contributing
groupsincreasedmeanW10values,butonlythetreatment factorishighlightedbythegraphsofpre-topost-change
group’spost-testingvalues increasedsignificantlyrelative inW10(Figure2).Close evaluationofthesegraphs indi-
to pre-testing values (229 to 243 W; Table 2). However, cate that most subjects increased the W10 regardless of
neithercardiorespiratorynorbloodlactatemeasureschan- group assignment. Thus, despite the previous evaluation
ged significantly for either group. Additionally, pre- to of UBP10 reliability described in the Methods section, it
post-change in W10 values (Figure 2) showed that most seemslikelythattheUBP10testwasmoreskilldependent
subjects within both groups actually increased W10from than the UBP60 test. This also suggests that the single
pre- to post-testing(9 of 12 for placebo group and 11 or familiarization visit was not sufficient for all subjects to
12fortreatmentgroup). achieverepeatableW10valueswithsuccessivevisits.
There are several factors that may have contributed to
the UBP10testslackof complete consistency with those UBP60 Test
from the constant-power and UBP60 tests. First, given TheUBP60 test,thelast ofthethreeUBPtestsadminis-
thateachofthesetestsrequiredonly10-secsof maximal tered, required skiers to maintain the highest average
effortfollowedby2.5minsofcompleterestbetweeneach UBP over the course of 60 seconds of double-poling.
trial,significantpre-topost-changesrelatedtotheUBP10 Interestingly,notonlydidpeakvaluesforHR(177versus
Table 5Summaryoxygenconsumption (VO ,L/min) measures resulting from five upperbody powertests
2
Group Test Constant UBP10 UBP10 UBP10 UBP60
Period Power Test Test Test Test
Test Trial#1 Trial#2 Trial#3
Placebo Pre-Test 2.68±0.28 2.29±0.22 2.55±0.20 2.63±0.19 3.14±0.24
(n=12)
Post-Test 2.72±0.30 2.47±0.23 2.88±0.23 2.74±0.21 ‡3.38±0.26
Treatment Pre-Test 2.84±0.29 2.34±0.18 2.61±0.17 2.65±0.19 3.43±0.25
(n=12)
Post-Test †2.77±0.28 2.33±0.21 2.67±0.23 2.68±0.20 ‡3.26±0.26
NOTE:AllvaluesexpressedasMean±SE;UBP10=10-secupperbodypowertest;UBP60=60-secupperbodypowertest
†Post-testmeasureofVO forConstant-Powertestwasnearlysignificantlylowerthanpre-testmeasurewithinthetreatmentgroup(P<0.10)
2
‡Post-testmeasureofVO2forUBP60testweresignificantlydifferentthanpre-testmeasurewithinthecorrespondingtestgroup(P<0.05)
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Table 6Summaryminute ventilation (V ,L/min) measures resulting from five upper bodypowertests
E
Group Test Constant UBP10 UBP10 UBP10 UBP60
Period PowerTest Test Test Test Test
Trial#1 Trial#2 Trial#3
Placebo Pre-Test 100.6±11.5 87.9±10.0 99.4±10.2 110.4±9.4 147.2±12.1
(n=12)
Post-Test 100.7±13.2 92.3±9.9 109.8±9.9 113.9±10.1 148.6±13.2
Treatment Pre-Test 104.6±11.7 102.9±7.7 126.0±12.8 129.7±10.3 163.5±12.0
(n=12)
Post-Test 101.7±10.6 97.3±9.8 122.4±11.8 132.1±12.9 †153.3±11.1
NOTE:AllvaluesexpressedasMean±SE;UBP10=10-secupperbodypowertest;UBP60=60-secupperbodypowertest
†Post-testmeasureofVEforUPB60testwasnearlysignificantlylowerthanpre-testmeasureswithinthetreatmentgroup(P<0.10)
184BPM;Table4),VO (3.26versus3.43L/min;Table5), the UBP60 test was though apriori to be most sensitive
2
and minute ventilation (V - 153.3 versus 163.5 L/min; tocreatingsignificantcardiorespiratoryandbloodlactate
E
Table6)alldecreasedsignificantlyforpost-testinginthe changes following the ANS loading. Numerous studies
treatmentgroup,butthesamegroupalsogeneratedmore investigating the influence ofNaHCO supplementation
3
UBPfollowingthe7-dayloadingphase(190to198Wfor onindicatorsofperformance have used30-120sec time
W60;Table3).Inaddition,thelasttwopost-testingrecov- intervalsfortesting,aswellasrepeattestintervalsfollow-
ery blood lactate measures (L7 and L8) for the UBP60 ing fixed rest intervals, to emphasize the use of non-
tests were significantly lower forthe treatment group.In mitochondrial ATPproductionandsubsequentintracel-
contrast, the placebo group showed no change in W60, lular acidosis (for a review see Williams [14]). Thus,
peak HR, or peak V while also showing significant whetheracidosiswasinducedacutelybythe60-sectime
E
increases in peak VO (Table 5) and the final recovery frameoftheUBP60test,orbytheaccumulationofthree
2
blood lactate (L8;Table 7)following the placebo group’s tests administered successively, or by a combination of
7-dayloadingperiod.Collectively,theseobservationssug- these factors,the influenceof ANSloadingon the treat-
gest that the treatment group experienced less cardiore- ment group was similar to what has been described for
spiratory stress and lower recovery blood lactate values NaHCO supplementation. Specifically, the treatment
3
whilegeneratingmoreaveragepowerduringpost-testing. groupwascapableofgeneratinghigherW60valueswhile
In contrast to the individual changes in W10 between experiencing lower cardiorespiratory stress and lower
pre-andpost-testing(Figure2),theindividualchangesin recovery blood lactate values. These observations may
W60(Figure3) showed thatalltreatment groupsubjects support the claims by the ANS manufacturer of a more
increasedW60frompre-topost-testingwhiletheplacebo rapidrecoveryofmusclefunctionfollowingpriorintense
groups’responseswerehighlyvariable.Again,incombina- muscularefforts.
tion withthesignificantchangesincardiorespiratoryand
recovery blood lactate measures, the treatment groups’ Possible mechanism for observed effects?
®
post-testingresponsestotheANSloadingsuggestspossi- The Alka-Myte -based supplement evaluated by this
bleergogenicbenefits. study is purported to be a mineral-based intracellular
Given that the UBP60 test was the last of three tests andextracellularalkalizingagentthathelpsminimizethe
administered, as well as the 60-sec test time for testing, influenceofmetabolicacidosisandmusclefatigueduring
Table 7Summarymeasures foreight (L1-L8) fingertip blood lactateanalyses (mmol/L)from testsofupper body
power
Constant-PowerTest UBP10Tests UBP60Test
Group †L1 L2 Trial#1 Trial#2 Trial#3 L6 L7 L8
L3 L4 L5
Placebo 5.3±0.6 5.0±0.6 5.1±0.6 5.6±0.5 6.4±0.6 9.2±0.5 9.8±0.6 9.7±0.6
Pre-Testing 4.9±0.6 5.0±0.7 4.9±0.6 5.6±0.5 6.6±0.5 9.4±0.5 10.3±0.6 ‡10.3±0.6
Post-Testing
Treatment 7.0±0.6 5.8±0.8 6.1±0.7 6.6±0.6 7.2±0.6 9.8±0.8 10.9±0.7 10.4±0.7
Pre-Testing ‡5.5±0.6 5.7±0.7 5.6±0.7 6.3±0.6 7.2±0.7 9.4±0.7 ‡9.8±0.7 ‡9.4±0.6
Post-Testing
NOTE:AllvaluesexpressedasMean±SE;UBP10=10-secupperbodypowertest;UBP60=60-secupperbodypowertest.Samplesizesremainedat12subjects
pergroupforbothpre-andpost-testing
†Theeightbloodlactatesamples(L1-L8)arelabeledthesameasthoseshownwithinFigure1
‡Meanpost-testingbloodlactatevaluedifferedsignificantly(P<0.05)fromcorrespondingpre-testingvaluewithinthesametestgroup