This lab report summarizes the results of indirect calorimetry tests performed on two subjects to determine their resting metabolic rate and substrate utilization. The first subject was a female weighing 58.18 kg and the second was a male weighing 76.36 kg. Unexpectedly, the results showed the first subject had a higher RMR of 1786 kcal/day compared to 1579 kcal/day for the second subject. The substrate utilization also differed from expected values at rest. Several possible factors are discussed to explain the discrepancies between the subjects and expected results, including differences in testing conditions and human error.

1. Jonathan Jeffrey
4/1/15
RMR Lab
HES 403
Lab Report Cover Page
Honor Pledge:
I pledgeon my honorthatI havenotreceived or given any unauthorized assistancein thisassignment.
Jonathan Jeffrey 4/1/15
Type Name Date
1. Rationale/Purpose:(5 pts) Subtotal
Required elements:
a. Provide a brief (~3-5 sentence) description of the rationale/purpose for this lab, and
the physiological system(s) tested.
Comments:
2. Methods:(5 pts) Subtotal
Required elements:
a. Briefly describe the methods used to collect the data you will present in the results
and discussion sections.
Comments:

2. 3. Results: (5 pts) Subtotal
Required elements:
a. Each lab will have specific requirements for how to share results (tables, figures
calculations, etc.). Please refer to the lab material and include the required
elements along with a brief description of what data are included.
Comments:

3. 4. Conclusions: (25 pts) Subtotal
Required elements:
a. Data obtained in the lab must be discussed in the context of materials from the
class/text, lab discussions, etc.
b. Discuss what the data mean, and norms or frames of reference for the values you
report in the lab (i.e., is the REE high, low, reasonable?). Provide the basis for any
normative assessment of the data.
c. Discuss the accompanying PDF in terms of:
a. The design and outcomes (conclusions) shared by the authors.
b. How the PDF informs your interpretation/discussion of data obtained in the
lab and/or how it expands upon material discussed in lecture.
c. Suggest a plausible follow-up study to the one presented in the PDF.
Comments:
Lab subtotal
Deductions for spelling/grammar/syntax, etc (maximum of 10 pts)
TOTAL SCORE (out of 40 pts):

4. Introduction:
The questionof calculatingmetabolicrate hasbeendiscussedforhundredsof years,withroots
as far back as the 1700’s. The notionof measuringmetabolicrate canbe referredtoas calorimetryand
was firstexaminedusingrodentsandglasschamberstoobserve temperature change. Understanding
metabolicrate can have importantimplicationsinmanydifferentareasincludingfitnessandhealth.
Metabolicrate can increase the understandingof weightgainanddisease risk,andalsooptimizationof
dietaryneedsrelatingtotraining. Indirectcalorimetrymeasuresoxygenconsumptionandcarbon
dioxide productiontodetermine howmuchenergyisbeingused.Indirectcalorimetrycanalsobe used
to determine whichsubstrate isbeingusedprimarilyinthe bodyforenergy;fator carbohydrates.
Proteinmetabolismaccountsforverylittle energyproductions,needstobe measuredusingurinary
analysis,andwill notbe examinedinthisexperiment. Restingenergyexpenditure isthe measure of how
manykcals are burnedwhenabodyisat rest.It representsalarge portionof the energyspentduring
the day and givesinsightintothe riskforweightgainandrelatedhealthissues. Understandingsubstrate
utilizationalsogivesinsightintothe riskfactorsforweightgainforinstance poorfatmetabolism.
UnderstandingRMRcan alsohelpclarifythe relationshipbetweenoverweightindividualsandenergy
expenditure basedonbodyarea,andthe relationshipbetweenfatmassandfat free mass.
The purpose of thislab isto use indirectcalorimetrytodetermine the oxygenconsumption,
carbon dioxide production,respiratoryexchange ratio,percentfatutilization,percentcarbohydrate
utilization,andenergyexpenditure of twoindividualsatrest.
Methods:
Two subjects of differentsize were selectedtoparticipate inthisstudy;one male;one female.
The subjects’anthropometricdatawascollected,alongwithfactorsthatmay affectRMR such as food
eatenthatday, activitylevelthatday(exercise) orcaffeineconsumedthatday.The ATPS (ambient
pressure,saturation) wasmeasuredinthe room;the ambienttemperature,barometricpressure,and
watervapor saturation.These valueswere enteredintothe computerprogram, True 1, which was
connectedtothe Oxygenanalyzer.The programstandardizedthe readingstoSTPD;standard
temperature andpressure,dry,(the standardforanalyzinganatmosphere).The machine iscalibrated
using4 readingsof airsamplespushedthroughthe oxygenanalyzerusinga3L syringe,withincreasing
speed.Once the machine hasbeencalibrated,the breathingapparatusisassembled,creatinga
mouthpiece withtwoone wayvalves,attachedtoa tube leadingtothe oxygenanalysismachine.The
subjectlaysona table ina supine position atrestand putsthe mouth piece intheirmouth, the oxygen
tube issuspendedabove the subjectsotheydon’thave toholdit up,and theybeginbreathingintothe
apparatus.The oxygenanalyzerrecordsthe percentage of oxygenconsumed,percentageof CO2
producedandtotal ventilation,andthe True 1 computerprogramrecords the data. The subject
breathedintothe apparatusfor20 minutes. Afterdatacollection,the Haldane transformation
equationsare usedtodetermine VO2,VCO2,R.E.R.,R.M.R,and% fat substrate utilizationand
carbohydrate substrate utilizationcanbe determinedbylookingata chart basedon RER.

5. Results:
Table 1: Subject1 AnthropometricData
Gender F
Age 20
Weight(kg) 58.18
Heightcm 157.48
Physical Activity None
Other Coffee duringthe day
Table 2: Subject1 Gas Analysis
% FE02 Average 16.80720901
% FECO2 Average 3.625238797
VE STPD Average (L/min) 5.948995534
Table 3: Subject1 Haldane TransformationSubstrate Utilization
VO2 4.397 ml/kg/min
VCO2 3.676 ml/kg/min
RER .84
REE (Kcal/min) 1.241
REE (Kcal/day) 1786.51
% Fat utilization 52.8%
% Carbohydrate Utilization 47.2%
Table 4: Subject2 AnthropometricData
Gender M
Age 26
Weght(Kg) 76.36
Height(cm) 170.18
Physical Activitythatday None
Other Coffee duringthe day
Table 5: Subject2 Gas analysis
%FEO2 Average 16.2199843
%FECO2 Average 4.035069
VE STPD Average (L/min) 4.872464

6. Table 6: Subject2 Haldane Transformation,SubstrateUtilization
VO2 (ml/min/kg) 3.126
VCO2 (ml/min/kg) 2.757
RER .88
REE Kcal/min 1.097
REE Kcal/day 1579.37
% Fat utilization 39.2
% Carbohydrate Utilization 60.8
Subject1 was female,20yearsold,weighed58.58 kilogramsandwas157.48 cm tall.She had
not performedany physical activitythroughoutthe daybesidesattendingclassesandmovingaround.
She had consumedcoffee thatdaywhichintroducedcaffeineintohermetabolicpathways.She was
foundto have an average oxygenconsumptionof 16.80720901%, an average CO2 consumptionof
3.625238797% and an average ventilationof 5.948995534 L/min.Subject1’sVO2 was 4.397 ml/min/kg,
herVCO2 was 3.676 ml/min/kgandherR.E.R.was.84, correspondingwithafatutilizationof 52.8%and
a carbohydrate utilizationof 47.2%. HerRestingEnergyExpenditurewascalculatedto1.241 Kcal/minor
1786.51 Kcal/day.
Subject2 was male,26 yearsold,weighed76.37 kg and was170.18cm tall.He had alsonot
performedandphysical activitythroughthe daybesidesmovingaroundthe campusand attending
classes,andhad alsoconsumedcoffee thatday.He wasfoundto have an average O2 consumptionof
16.2199843%, an average CO2 consumptionof 4.035069% and an average ventilationof 4.872464 L/min.
Subject2’s VO2 was3.126 ml/min/kg,hisVCO2 was2.757 ml/min/kgand hisR.E.R.was.88,
correspondingwithafatutilizationof 39.2% and a carbohydrate utilizationof 60.8%. Hisrestingenergy
expenditure wascalculatedto1.097 Kcal/minor1579.37Kcal/day.
Discussion:
The resultsseeninthislab seemedunusual.Itwouldbe expectedthatsubject2,withthe higher
bodyweight,therefore higherfatfree massandfat masswouldhave a higherRMR. Subject2’s RMR
was 1579.37/ Kcal/dayandsubject1’s RMR was 1786.51 Kcal/day. Accordingto these resultssubject2’s
RMR wasover200 kcal lessperdayeventhoughsubject1 was 18.18 kg lessat 58.18kg vs 76.36 kg. This
couldbe due to multiple factors.Subject1sactivitylevel couldhave beenhigherthanreportedforthe
day,or subject1 couldhave consumedaconsiderable amountof caffeine whentheyhadcoffee earlier,
raisingtheirRMR. Caffeine competitivelyinhibitsphosphodiesterase,aCyclicAMP - degradingenzyme,
therefore increasingthe activityof CAMPproteinkinases,raisingmetabolicrate andstimulatingthe
entire central nervoussystem.(Metabolismof Caffeine) A tolerance canbe builtupto caffeine and
differentpeoplereacttocaffeine differentlydependingontheirtolerance. Subject1couldhave been
nervoustotake the test, or perhapsdidn’tlike havingthe breathingapparatusintheirmouth(the
breathingapparatuscan be invasive anduncomfortable),whichcouldhave hadaneffectonherRMR.
She couldhave beenrushingtogetto class on time andhad an elevatedheartrate.Anotherreasonthey
couldhave gottensuch differentreadingscouldbe thatthe machine wascalibrateddifferently foreach
test,consideringthe testswere done ontwodifferentdays.Humanerrorinsome way couldexplain

7. these differentresults.Considering,though,thatsubject1has a considerablylargerbodymass,itis
unlikelythatthese resultsare accurate. Asfar as the calibrationof the machine goes,the readingsfor
subject1 were calibratedbythe instructorandthe readingsforsubject2, on the secondday were
calibratedbythe studentsof the class.
Whenexaminingthe substrate utilizationof eachsubject,theywere bothmetabolizingmore
carbohydrate thanexpected.Atrest,itisexpectedtosee around90% fatutilizationand10%
carbohydrate utilization.Inthese trials,subject1 wasutilizing52.8% fatas a substrate forenergyand
47.2% carbohydrates. Subject2was utilizing39.2% fatfor energyand60.8% carbohydrate. Tofindthe
relationshipbetweensubstrate utilizationandgasexchange the chemical equationof the breakdownof
glucose andfat inthe body isexaminedwhenglucose isbrokendown,6 O2 moleculesare presentat
the beginningof the reactionand6 CO2moleculesare presentatthe endof the reaction.Thisratio of
CO2 : O2 isone.Therefore if respiratoryexchange ratioisone,onlyglucose isbeingusedforenergy.For
fat,23 moleculesof O2 are usedand 16 moleculesof CO2 are produced.Inthisinstance 16/23 = .7, so if
the RER is.7, thenonlyfat isbeingusedforenergy.Anyfiguresbetween1and.7 representabalance of
fat and carbohydrate substrate utilization. These substrate percentagesindicate thatthe subjectswere
not trulyat rest,whichmakessense because thesetestswere performedlaterinthe dayaround 4 pm,
aftera full dayof eating,movingaround,andperformingdailyactivities.The factthatsubject1 was
utilizingmore fatasa substrate thansubject2 pointstothe fact that theywere possiblymore “atrest”
than subject2, whichevenfurthercreatesadiscrepancybetweenwhatwouldbe expectedintermsof
RMR. Itcouldbe possible thatsubject2doesn’tutilize asmuchfat as a substrate at restdue to the
efficiencyof one metabolicpathwayvsthe other,butstill seemedunlikelythatsubject1 burnedmore
fat at restbecause subject2 had a noticeablyhigherfatfree mass,whichisconsideredthe biggestfactor
indeterminingRMR,andmore than likelyalowerbodyfatpercentage because subject1isfemale,and
subject2 is male,andmengenerallyhave lowerbody fatpercentages,whendiscussingpopulationsthat
are notoverweight,whichneithersubjectis. Somethingelsetoconsiderwouldbe whateachsubjectate
that day.It couldbe possible thatsubject1 hadmore fatin theirdietthatday, causingher fatsubstrate
metabolismtobe higherthanthatof subject2 whocouldhave eatena low fat dietthatday.
Anotherfactorthat couldhave contributedtothe discrepancyinRMR is the fact that subject1’s
ventilation waslargerthansubject2. Subject1’sventilationwas5.95l/minonaverage and subject2’s
VE was4.87, 1.08 l/minlessthansubject1.Subject1 couldhave a larger lungcapacitythan subject2 but
againthat is highlyunlikelybecauseof the sheerdifference insize betweenthe twosubjects.Itcouldbe
possible thatsubject1was deliberatelytakingdeepbreathsdue tothe awarenessof beingtestedfor
gas exchangeswithabreathingapparatus intheirmouth.
Anotherstudypublishedinthe NRCresearchpressonRMR wasexamined forthislab,during
whichsubjectswere subjectedtosprintexercisesandtheirappetite andenergyintake wasmeasuredin
relationshiptotheirexercise performed,alsolevel of hunger-relatedpeptideswere measuredafter
exercise.Theyfoundthatsprint interval exercise increasedoverall feelingsof hungerbutnotan increase
inenergyintake whensubjectswere allowedtovoluntarilyeatasmuch as theywantedinbuffet- style
settings.The findingssupportedacorrelationbetweensprintintervalexerciseandfatlossforweight
managementpurposes,pointingthe fatthatsustainedintervalexerciseovertime couldhelpfatloss
programs. (Abbotetal)

8. A good followupstudyforthistestwouldbe totest bothsubjectsagain,atthe same time,
underbettercircumstancesforcalculatingRMR.For instance,firstthinginthe morningbefore anyfood
or coffee hasbeenconsumed,inaquietroom, withthe same controllerconductingthe testand
calibratingthe equipment.
Appendix:
Subject1 Haldane Transformations:
𝑉𝑂2 = 𝑉𝐸 𝑆𝑇𝑃𝐷 𝑋 {(
%𝑁2 𝐸
. 7904
) 𝑋 .2093 − %𝑂2 𝐸}
%N2E=((100-(16.80720901+3.625238797))
%N2E=79.6%
.796/.7904= 1.007
1.007 X .2093 = .2107651
.2107651-.1680720901 =.043
.043 X 5.948995534 = .2558 L/minO2
1000 x .2558 = 255.8 ml/min
255.8 ml/min÷58.18 kg = 4.397 ml/min/kg
Subject1 VCO2:
VCO2 = VE STPD X (%CO2E -0.03%)
5.948995534 X (.03625238797-.0003) = .213880595
.21388095 X 1000 = 213.880595 ml/min
213.880595/58.18 = 3.676 ml/min/kg
R.Q. = VCO2 ÷ VO2
R.Q. = 3.676 ml/min/kg÷4.397 ml/min/kg=.84
= 4.85 kcal/LVO2

9. R.E.E. :
4.85 ÷ 1 l/minx .2558 l/minO2 = 1.24063 Kcal/min
1.241 Kcal/minx 1440 min/day= 1786.51 Kcal/day
Subject2 Haldane Transformations:
𝑉𝑂2 = 𝑉𝐸 𝑆𝑇𝑃𝐷 𝑋 {(
%𝑁2 𝐸
. 7904
) 𝑋 .2093 − %𝑂2 𝐸}
100- (16.2199843 + 4.035069) = 79.7449
.797/.7904 =1.00835
1.008 X .2093 = .2109744
.2109744 - .162199843 = .049
.049 X 4.872464 = .23875 L/minO2
.23875 X 1000 = 238.7 ml/minO2
238.7 ml/min÷76.36 kg = 3.126 ml/min/kg
Subject2 VCO2:
VCO2 = VE STPD X (%CO2E -0.03%)
4.872464 X (.0435069 -.0003) = .210524065
.210524065 X 1000 = 210.524065 ml/min
210.524065/76.36 kg = 2.757 ml/min/kg
R.Q. = VCO2 ÷ VO2
2.757ml/min/kg÷ 3.126 ml/min/kg=.88
= 4.899 Kcal/ L O2
REE:
4.899 Kcal/LO2 X .22388 L/minO2 = 1.097 kcal/min
1.097 kcal/minX1440 min/day= 1579.37 kcal/day

10. References:
Abbot,K.,Beaulieu,K.,Lemon,P.,Olver,D.T.,(2015) Energy Intake over2 Days isUnaffectedbyAcute
SprintInterval Exercise despiteIncreasedAppetiteandEnergyExpenditure. Applied Physiological
NutrientMetabolism40, 1-7. http://www.nrcresearchpress.com
(2011, October) Metabolismof Caffeine. Effectsof Caffeine. Retrievedfrom
http://udel.edu/~danikoll/metabolism.html