The Combined Effects of Exercise and Ingestion of a Meal Replacement in Conjunction with a Weight...

THE COMBINED EFFECTS OF EXERCISE AND

INGESTION OF A MEAL REPLACEMENT IN

CONJUNCTION WITH A WEIGHT LOSS SUPPLEMENT ON

BODY COMPOSITION AND FITNESS PARAMETERS IN

COLLEGE-AGED MEN AND WOMEN

CHRIS N. POOLE,1 MICHAEL D. ROBERTS,2 VINCENT J. DALBO,3 PATRICK S. TUCKER,1

KYLE L. SUNDERLAND,1 NICK D. DEBOLT,1 BRETT W. BILLBE,1 AND CHAD M. KERKSICK1

1Applied Biochemistry and Molecular Physiology Laboratory, Health and Exercise Science Department, University ofOklahoma, Norman, Oklahoma; 2Department of Biomedical Science, University of Missouri-Columbia, Columbia, Missouri; and3Institute of Health and Social Science Research, School of Medicine and Applied Sciences, Central Queensland University,Rockhampton, Australia

ABSTRACT

Poole, CN, Roberts, MD, Dalbo, VJ, Tucker, PS, Sunderland, KL,

DeBolt, ND, Billbe, BW, and Kerksick, CM. The combined

effects of exercise and ingestion of a meal replacement in

conjunction with a weight loss supplement on body compo-

sition and fitness parameters in college-aged men and women.

J Strength Cond Res 25(1): 51–60, 2011—This study was

performed to evaluate the combined effect of a meal re-

placement and an alleged weight loss supplement (WLS) on

body composition, fitness parameters, and clinical health in

moderately overweight college-aged men and women. Body

mass, bench press 1 repetition maximum (1RM), leg press

1RM, body composition, _VO2max, fasting glucose (GLU), and

lipid panels were evaluated before (T1) and after (T2) 8 weeks

of combined resistance training (RT) and cardiovascular

training (CVT). After T1, subjects were randomly assigned

in a double-blind fashion to either the WLS (6 men, 7 women;

21 6 5 years, 168 6 8 cm, 75.4 6 12.7 kg, 31.6 6 7.7%BFAT)

or placebo (PLA: 6 men, 6 women; 22 6 4 years, 174 6 9 cm,

84.1 6 8.8 kg, 30.2 6 5.6%BFAT) group. Both groups

performed 3 d�wk21 of combined progressive RT (2 3 12 reps

of 8 exercises at 75–80% 1RM) and CVT (30 minutes on

a cycle ergometer at 70–85% heart rate reserve). Subjects

consumed 4 capsules per day and a once-daily meal

replacement throughout the protocol. Percent body fat, bench

press 1RM, and leg press 1RM significantly improved (p ,

0.05) in both groups. Blood GLU (G 3 T; p = 0.048) improved

in WLS and systolic blood pressure (SBP) approached

significance (G 3 T; p = 0.06) in the WLS group. Follow-up

analysis of SBP revealed a significant within-group decrease in

the WLS group, whereas no within-group changes were found

for either group for GLU. Practically speaking, daily supple-

mentation with a meal replacement and a thrice weekly exercise

program can increase fitness levels and improve body

composition, whereas adding a thermogenic substance pro-

vides no additional benefit over fitness or body composition

changes but may favorably alter serum markers of clinical health.

KEY WORDS thermogenic, protein, resistance training, aerobic

training

INTRODUCTION

Recent data from the National Center for Healthsuggest that approximately 60% of US adults areoverweight, and 24% are obese (22). Thesestatistics have increased public interest in over-

the-counter weight loss supplements (WLSs), with consum-ers spending an estimated $37.1 billion per year (2).Numerous dietary supplements have been marketed asa means of increasing energy expenditure, and they containactive ingredients that increase the activity of the thyroidgland, sympathetic nervous system, and metabolic processeswithin adipose tissue and skeletal muscle such as lipolysis andfatty acid oxidation, respectively (5,6,11,27). In accordancewith the aforementioned data, our laboratory has demon-strated that a thermogenic beverage containing caffeine andgreen tea catechins transiently increased resting energyexpenditure, serum markers of lipolysis, and fatty acidoxidation in young, college-aged men and women (11).

Although widespread research tends to support the notionthat over-the-counter thermogenic supplements or beverages

Address correspondence to Dr. Chad M. Kerksick, [email protected].

25(1)/51–60

Journal of Strength and Conditioning Research� 2011 National Strength and Conditioning Association

VOLUME 25 | NUMBER 1 | JANUARY 2011 | 51

Copyright © National Strength and Conditioning Association Unauthorized reproduction of this article is prohibited.

favorably alter indices associated with lipolysis, products thatare tested in laboratory settings typically contain explicitformulations of active ingredients. In this respect, manyformulations include as active ingredients (a) caffeine and itsanalogs (e.g., theobromine, theophylline), (b) citrus auran-tium, a purported modulator of catecholamine release inadipose tissue and liver, and (c) green tea extract, EGCG, orother tea catechins. With regards to the efficacy of one ormore of these ingredients, past research has demonstratedthat ingesting 100–400 mg of caffeine alone transientlyincreases metabolic rates in a dose-dependent fashion (1).Furthermore, consuming caffeine on a daily basis withexercise has been shown to facilitate greater increases in fatloss in exercising obese women as evidenced throughcorrelational analyses (i.e., those that experienced a morethermogenic metabolic response to caffeine lost moreweight). A similar study has found that consuming dailycitrus aurantium (975 mg) and caffeine (500 mg) significantlyreduced body mass by 1.5% compared to a nonsignificant1.0% reduction in a placebo condition when these subjectsregularly exercised for 6 weeks (4). Likewise, administeringa combined caffeine and EGCG supplement to moderatelyoverweight subjects has proven to be effective in significantlyreducing body mass by 0.9 kg over an 8-week periodcompared to a placebo supplement (3). Therefore, these dataillustrate a slight potential for thermogenic ingredients to actin a synergistic fashion to facilitate reductions in body fat.However, a limited number of studies have analyzed finished,commercially available thermogenic products containinga multitude or blend of ingredients designed to promote fatloss over a period of weeks or months. For this reason aloneand in light of their popularity, more research is warrantedthat examines their efficacy in conjunction with chronicresistance exercise alone, or combined with cardiovascularexercise on markers of health and body composition.

The importance of consuming a healthy diet with ampleprotein has become a focal point for those interested in buildinglean tissue or losing fat mass while undergoing an exerciseprogram. Researchers have employed such a strategy bymanipulating macronutrient percentages in assigned diets (17)or by providing study subjects undergoing chronic resistance andcardiovascular exercise a daily meal-replacement product (18),both of which increased overall protein intake in a subset of thesubjects, to positively affect body composition, performancemeasures, and clinical safety markers. Based on the above dataregarding thermogenic ingredients and dietary protein manip-ulation, the potential exists for a thermogenic product, inconjunction with a diet supplemented with protein andconcurrent exercise, to positively impact body compositionand clinical safety markers.

Research has also consistently demonstrated that exercise-induced improvements in body composition may help staveoff or reverse the negative effects of increased adiposity suchas a dysregulation in glucose (GLU) disposal and insulinsignaling, dyslipidemia, and subsequent disease states such as

cardiovascular disease and type II diabetes (19,25). Becauseexercise is known to increase energy expenditure andsympathetic nervous system activity and improve overallhealth markers, great interest has surrounded the potentialsummative physiological effects that exercise, a daily meal-replacement and thermogenic supplement ingestion possess.However, data are lacking concerning how consumption ofthermogenic supplements and exercise synergistically impactholistic physiological variables including body composition,strength and cardiorespiratory fitness markers, bloodmarkers indicative of metabolic syndrome disease risk (i.e.,fasting blood GLU and blood lipids), and cardiac functionduring exercise. Therefore, the purpose of our study was toperform a randomized, double-blind, placebo-controlledstudy to examine what impact adding a commerciallyavailable WLS in combination with a regular exerciseprogram and daily protein supplementation had on bodycomposition and fitness parameters in a group of moderatelyoverweight college-aged students.

METHODS

Experimental Approach to the Problem

A double-blind, placebo-controlled investigation was used asthe study design for this investigation. A double-blind,placebo-controlled approach was used for its ability toeffectively remove any investigator bias and placebo controlallows for a clear determination of the effects from the chosenexercise and dietary program with and without the addedWLS. To ensure group homogeneity before commencing thestudy, subjects were distributed equally by gender into groupsand matched according to prestudy body mass. All subjects(N = 24) were allocated to ingest 2 daily doses (2 capsules perdose or 4 capsules total) of either a WLS (n = 12; men: n = 6and women: n = 6) or PLA (n = 12; men: n = 6 and women:n = 6) with concomitant resistance and cardiovascularexercise performed 3 d wk21 each, respectively, for the8-week study duration. Additionally, all subjects ingesteda daily meal-replacement supplement to promote anadequate daily protein intake and to help standardize thefeeding environment surrounding each workout. To effec-tively determine changes in fitness, body composition, andclinical health, all subjects were tested at baseline (T1) andafter 8-weeks (T2) for body composition, exercise perfor-mance, and clinical health as determined through bloodserum analyses. Primary outcome variables include bodycomposition measures, secondary outcome variables includechanges in performance assessments, and tertiary outcomesconsisted of changes in clinical health. It is hypothesizedfrom previously related research that daily and twice-dailyingestion of a meal replacement and WLS, respectively, incombination with an exercise program consisting of 3 dayseach of resistance and cardiovascular exercise will improvebody composition more so than supplementing with a mealreplacement alone. Additionally, it is hypothesized that all

52 Journal of Strength and Conditioning Researchthe TM

Meal Replacement and Thermogenic Supplementation and Exercise


subjects will respond similarly to the exercise program andexperience similar improvements in all posttesting perfor-mance assessments. The WLS supplementation is expectedto have no adverse effects on any clinical health variables ofinterest.

Subjects

Twenty-four sedentary, college-aged men and women (n = 24:21.5 6 4.5 years, 171.0 6 8.7 cm, 79.9 6 11.8 kg, 30.6 6 6.6%BF;mean 6 SD) were informed of the experimental procedures and

signed informed consent state-ments and medical history formsin adherence with the Institu-tional Review Board of theUniversity of Oklahoma andthe American College of SportsMedicine (ACSM) before datacollection. All subjects beforecommencing the study wereconsidered to be recreationallyactive, but were not regularlyparticipating (#1 d�wk21) in anyform of an exercise program(resistance training [RT], groupfitness, or aerobic exercise). Sub-jects were excluded if they (a)had any history of metabolic,hypertension, hepatorenal, mus-culoskeletal, autoimmune, orneurological disease; (b) werecurrently taking thyroid, antihy-perlipidemic, hypoglycemic, an-tihypertensive, or androgenicmedications; and (c) had takennutritional supplements that mayaffect metabolism (i.e., over 100mg�d21 of caffeine or otherthermogenic ingredients includ-ing: ephedrine, synephrineanalogs, EGCG, yohimbineHCl, guggulsterones, etc.) an-d/or muscle mass (i.e., creatine,protein, amino acids, androste-nedione, dihydroepiandroster-one, etc.) within 3 months ofstarting the study.

Study Design

After the informed consent wassigned, eligible subjects werefamiliarized to the study pro-tocol via a verbal and writtenexplanation of the study design.Subjects were instructed to re-frain from unaccustomed exer-

cise for 24 hours, and fast for 12 hours before baseline (T1) andfollow-up (T2) testing. In a randomized, double-blind,placebo-controlled design subjects were distributed equallyby gender into groups and matched according to prestudybody mass and instructed to consume a once-daily meal-replacement supplement (see Table 1) and either a twice-daily placebo (PLA) or a twice-daily WLS. Within 1 week ofbaseline testing, all subjects began participation in a super-vised cardiovascular and RT program, 3 d�wk21, over the8-week (56-day) intervention.

TABLE 1. List of ingredients in WLS (serving size: 2 capsules).*

Ingredient Amount

1. Lysine L-carnitine fumarate 600-mg Blend of ingredients 1–42. Citrus aurantium3. 7-Keto dehydroepiandrosterone4. Theobromine5. Caffeine and green tea extract 600-mg Blend of ingredients 5–66. White willow bark7. Dimethylethanolamine 100 mgMeal-replacement supplement facts per serving (serving size: 1 packet [56 g])Calories 230Total fat 6.5 gSaturated fat 4 gCholesterol 80 mgSodium 370 mgTotal carbohydrates 6 gDietary fiber 1.5 gSugars 4 gProtein 35 gVitamin A 2,000 IUVitamin C 30 mgVitamin D 200 IUVitamin E 30 IUThiamin 750 mgRiboflavin 850 mgNiacin 10 mgVitamin B6 1 mgFolate 200 mgVitamin B12 3 mgBiotin 150 mgPantothenic acid 5 mgCalcium 500 mgIron 9 mgPhosphorus 500 mgIodine 75 mcgMagnesium 200 mgZinc 7.5 mgSelenium 21 mgCopper 1 mgManganese 1 mgChromium 60 mgMolybdenum 15 mgChloride 300 mgBoron 1 mg

*WLS = weight loss supplement.


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Supplementation Protocol

Detailed information on WLS and the meal replacement canbe found in Table 1. After T1, subjects were assigned ina double-blind fashion to either the WLS or PLA group.Subjects were instructed to ingest 2 pills in the morning and 2pills in the late afternoon with meals on a daily basis over theentire 8-week intervention. To monitor compliance, subjectswere administered the pills in 2-week batches (2 pills 3 2doses 3 14 days = 56 pills), with compliance checks at theend of every 2-week period. This approach allowedresearchers to keep a log of subject compliance. Pills werepackaged in generic bottles without identifying labels andwere capsulated in identical opaque capsules. Subjects werealso administered a meal-replacement supplement (LowCarbUltramet�, Champion Nutrition, Concord, CA, USA)and were instructed to ingest one serving per day (perserving: 220 kcals, 35 g protein, 6 g carbohydrates, 6 g totalfat). The meal replacement was provided as part of a generaldiet plan whereby all subjects were instructed to reduce theircaloric intake and to help standardize the nutritional intakesurrounding each workout to ensure optimal timing of othernutrients did not facilitate improved physiological adapta-tions to the supplementation and exercise program. Themeal-replacement supplement was not blinded to thesubjects or the investigators. As with the WLS, subjectswere given a 2-week supply of meal replacements, witha compliance check at the end of every 2-week period anda compliance log maintained for each subject.

TABLE 2. Exercise training protocol employed overthe 8-week intervention.*

Cardiovascular training protocol

Weeks Duration (min) Intensity

1–2 30 70% Age-predictedHRmax




Progressive resistance training protocol†‡Week Sets Repetitions Intensity1–2 2 12 12RM3–4 2 12 12RM5–6 2 12 12RM7–8 2 12 12RM

*12RM = load which caused muscular failure on the12th repetition.

†Progression was implemented every 2 weeks bytrainers (i.e., 5–10 lbs for upper body exercises and10–15 lbs for lower-body exercises).

‡Exercises performed during resistance training in-cluded: hip sled, barbell bench press, leg extension, legcurls, seated machine military press, cable lat pulls, andcable rows.

TABLE 3. Total energy, macronutrient, and caffeine intake normalized to body mass in kilograms between and withingroups.*

Variable Group Pre Post Within group Between group

Energy (kcal�kg21�d21) WLS 30.2 6 12.0 26.5 6 9.8 0.10 G = 0.47PLA 25.8 6 11.6 24.6 6 11.9 0.66 T = 0.15

G 3 T = 0.45Protein (g�kg21�d21) WLS 1.1 6 0.4 1.4 6 0.5† 0.02 G = 0.20

PLA 0.9 6 0.3 1.1 6 0.6 0.24 T = 0.01G 3 T = 0.42

Carbohydrate (g�kg21�d21) WLS 3.9 6 1.8 3.0 6 1.3 0.06 G = 0.63PLA 3.4 6 1.6 2.9 6 1.3 0.12 T = 0.01

G 3 T = 0.41Fat (g�kg21�d21) WLS 1.1 6 0.5 1.0 6 0.6 0.41 G = 0.60

PLA 0.9 6 0.5 1.0 6 0.6 0.90 T = 0.77G 3 T = 0.60

Caffeine (mg�kg21�d21) WLS 0.3 6 0.5 0.5 6 0.8 0.55 G = 0.31PLA 0.4 6 0.5 0.3 6 0.4 0.19 T = 0.19

G 3 T = 0.71

*WLS = weight loss supplement group; PLA = placebo group.†Different from Pre, p , 0.05.




Training Protocol

The employed exercise program was modeled using theACSM recommended guidelines for apparently healthyadults. All subjects were supervised daily and trained byNational Strength and Conditioning Association (NSCA)certified individuals. Endurance training was performed oncycle ergometers 3 d�wk21 and consisted of 30 minutes ona cycle ergometer at a predetermined heart rate (70–85% age-predicted heart rate reserve) (Table 2). Likewise, RTconsisted of 2 sets of 12 repetitions of the following exercises:seated leg press, bench press, leg extension, leg curl, seatedmilitary press, lat pull, and cable row (75–80% 1 repetitionmaximum [1RM]) was performed 3 d�wk21 week immedi-ately after each endurance training session. Efforts weremade to ensure that exercise sessions occurred at least 24hours apart to allow for adequate recovery. The intensity of

cardiovascular exercise was increased according to theprogression outlined in Table 2 while progression of RTintensity had individuals exercising to failure on both sets ofeach exercise. When .12 repetitions were completed, theweight was adjusted and a new progression was established.A description of the training protocol is presented in Table 2.

Blood Pressure and Serum Analysis

During T1 and T2 testing sessions, subjects reported to thelaboratory in the morning after a 12-hour fast to donatea fasting blood sample and determination of resting bloodpressure, body composition, cardiorespiratory and musculo-skeletal fitness. Briefly, subjects rested in a seated position for5 minutes before manual blood pressure determination at thebrachial artery using standard blood pressure procedures.Subjects then donated approximately 6 ml of venous blood

TABLE 4. Body mass and body composition changes within and between groups.*


Body mass (kg) WLS 75.6 6 13.2 74.6 6 11.3 0.40 G = 0.05PLA 84.1 6 8.8 83.2 6 7.5 0.33 T = 0.20

G 3 T = 0.95Fat mass (kg) WLS 22.1 6 3.9 20.4 6 2.4 0.08 G = 0.06

PLA 26.8 6 7.6 25.1 6 7.6† 0.002 T = 0.002G 3 T = 0.94

Lean mass (kg) WLS 53.6 6 11.9 54.2 6 10.8 0.41 G = 0.32PLA 57.5 6 8.4 58.3 6 6.8 0.34 T = 0.20

G 3 T = 0.87Body fat (%) WLS 29.5 6 5.3 27.8 6 4.8† 0.03 G = 0.42

PLA 31.7 6 7.7 29.9 6 7.7† 0.004 T = 0.001G 3 T = 0.96

*WLS = weight loss supplement group; PLA = placebo group.†Different from Pre, p , 0.05.

TABLE 5. Changes in fitness parameters within and between groups.*


_VO2max (LO2�min21) WLS 3.0 6 0.78 3.1 6 0.77 0.80 G = 0.69PLA 2.9 6 0.8 3.1 6 0.69 0.08 T = 0.92

G 3 T = 0.151RM bench press (kg) WLS 56.3 6 26.4 63.8 6 27.3† 0.002 G = 0.35

PLA 46.8 6 15.4 56.2 6 17.2† 0.001 T , 0.001G 3 T = 0.52

1RM leg press (kg) WLS 239.0 6 57.0 289.7 6 70.4† 0.01 G = 0.49PLA 250.0 6 60.8 311.7 6 63.6† 0.002 T , 0.001

G 3 T = 0.62

*1RM = 1 repetition maximum; WLS = weight loss supplement group; PLA = placebo group.†Different from Pre, p , 0.05.



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from their right forearm using standard venipuncturetechniques. The serum separation tubes were centrifugedat room temperature for 15 minutes at 3,500 rpm, the serumsupernatant was transferred into 2 microcentrifuge tubes, andthe serum samples were stored at 220�C for subsequentanalyses. Serum samples were batch analyzed for totalcholesterol (TCHOL), low-density lipoprotein cholesterol(LDL), high-density lipoprotein cholesterol (HDL), GLU,gamma-glutamyl transferase (GGT), aspartate aminotrans-ferase (AST), and alanine aminotransferase (ALT) usingautomated analyzers from a commercial diagnosticlaboratory.

Body Composition Assessment

After blood collection, height was measured using standardanthropometry and body composition parameters includingbody mass, lean mass, fat mass, and body fat percentage(%BF) were determined using air displacement plethysmog-raphy (Life Measurement Inc. Concord, CA, USA) (BODPOD). Body composition assessment was performed per theBOD POD manufacturer’s instructions. Subjects’ actualthoracic gas volume was measured and integrated softwareadjusted body volume for thoracic gas volume and calculated%BF using the Brozek et al. equation (7). Our laboratory haspreviously demonstrated an intraclass coefficient of 0.99 and

TABLE 6. Changes in hemodynamic and serum clinical safety markers within and between groups.*


Resting HR (b�min21) WLS 100.7 6 22.3 94.3 6 15.2 0.19 G = 0.57PLA 103.3 6 16.6 98.4 6 10.5 0.37 T = 0.12

G 3 T = 0.82Resting SBP (mm Hg) WLS 129.5 6 11.1 115.7 6 7.9† 0.002 G = 0.88

PLA 124.5 6 9.9 119.8 6 6.1 0.15 T = 0.001G 3 T = 0.06

Resting DBP (mm Hg) WLS 84.8 6 9.7 79.5 6 11.0 0.08 G = 0.65PLA 82.5 6 8.2 84.8 6 9.0 0.56 T = 0.51

G 3 T = 0.12Glucose (mg�dL21) WLS 96.9 6 10.7 93.2 6 5.6 0.22 G = 0.17

PLA 89.5 6 7.9 92.9 6 6.0‡ 0.10 T = 0.92G 3 T = 0.05†

Total cholesterol (mg�dL21) WLS 169.0 6 30.4 164.2 6 22.2 0.51 G = 0.52PLA 175.3 6 46.7 174.3 6 32.4 0.92 T = 0.23

G 3 T = 0.48HDL (mg�dL21) WLS 53.2 6 11.3 54.4 6 11.4 0.65 G = 0.33

PLA 48.3 6 9.8 50.8 6 13.0 0.37 T = 0.34G 3 T = 0.76

LDL (mg�dL21) WLS 95.4 6 22.5 90.2 6 12.7 0.30 G = 0.33PLA 102.9 6 37.9 103.4 6 26.7 0.95 T = 0.34

G 3 T = 0.75Triglycerides (mg�dL21) WLS 107.4 6 77.4 98.0 6 59.4 0.50 G = 0.75

PLA 119.9 6 60.5 100.2 6 30.0 0.18 T = 0.14G 3 T = 0.60

GGT (U�L21) WLS 17.7 6 8.0 18.0 6 7.8 0.82 G = 0.31PLA 15.7 6 6.1 14.5 6 5.0 0.36 T = 0.65

G 3 T = 0.43AST (U�L21) WLS 18.1 6 6.4 23.2 6 7.4 0.06 G = 0.56

PLA 18.6 6 8.0 19.8 6 6.9 0.55 T = 0.05G 3 T = 0.21

ALT (U�L21) WLS 12.7 6 8.0 16.9 6 7.7 0.18 G = 0.45PLA 11.2 6 4.7 15.2 6 4.6† 0.03 T = 0.01

G 3 T = 0.96

*WLS = weight loss supplement group; PLA = placebo group; HR = heart rate; SBP = systolic blood pressure; DBP = diastolicblood pressure; HDL = high-density lipoprotein cholesterol; LDL = low-density lipoprotein cholesterol; GGT = gamma-glutamyltransferase; AST = aspartate aminotransferase; ALT = alanine aminotransferase.

†Different from Pre, p , 0.05.‡Using delta values WLS , PLA, p , 0.05.




a total error of measurement of 2.65% in a population ofcollege-aged athletic women.

Fitness Testing

After body composition assessment, upper and lower-bodystrengths were determined using standard 1RM testingprocedures according to the guidelines of the NSCA witha bench press and 35� hip sled machine (Yukon FitnessEquipment, Cleveland, OH, USA). Test–retest reliability ofthese strength tests on resistance-trained subjects in ourlaboratory has yielded a high reliability for the bench press(intraclass correlation coefficient [ICC] = 0.996, p , 0.001)and leg press (ICC = 0.988, p , 0.001) (23). Finally, subjectsperformed a graded treadmill (Trackmaster Treadmill,Newton, KS, USA) exercise test employing the Bruceprotocol (8). The test was terminated once volitional fatiguewas attained, and _VO2peak was determined using indirectcalorimetry (True One 2400 Metabolic MeasurementSystem, ParvoMedics Inc., Sandy, UT, USA). Test–retestreliability of this measurement in our laboratory haspreviously been measured at an intraclass coefficient of0.952, p , 0.001.

Statistical Analyses

Separate 2 3 2 (condition [WLS vs. PLA] 3 time [PRE vs.POST]) repeated measure analyses of variance were usedto assess body composition, _VO2max, bench press and legpress 1RM, clinical safety markers (heart rate, bloodpressure, clinical serum markers), relative dietary con-sumption of kilocalories, macronutrients, and caffeine.Assumptions of normality were met with our data. Incircumstances where sphericity within groups could notbe assumed because of large within-group variances, theHunyhs–Feldt epsilon correction factor was used to adjustwithin-group F-ratios. When significant group 3 timeinteractions were found, separate independent t-tests wereperformed to assess which time points yielded statisticalsignificance between groups. Additional separate inde-pendent t-tests were used for the assessment of capsule,protein and exercise compliance. Significance for allstatistical analyses was determined using an alpha levelof 0.05, and all data are presented as mean 6 SDs. Post hocpower analysis of our results indicated observed powervalues of 0.818, 0.587, and 0.464 for body mass, fat mass,and lean mass, respectively.

RESULTS

Baseline Demographics

Baseline demographics revealed no significant differences(p . 0.05) for age (PLA: 22 6 4 years vs. WLS: 21 6 5 years;p = 0.90), weight (PLA: 85.4 6 9.1 kg vs. WLS: 76.8 6 13.2kg; p = 0.08), body mass index (PLA: 28 6 3 kg�m22 vs. WLS:26 6 3 kg�m22; p = 0.21) and percent body fat (PLA: 32 6 8%vs. WLS: 30 6 5%; p = 0.44).

Between-Group Calorie, Macronutrient, Caffeine Ingestion,

and Program Compliance Comparisons

Table 3 displays total calories, macronutrient, and caffeineingestion before and after 8 weeks of exercise and supplementintervention for WLS and PLA. No significant group 3 timeinteractions or main effects for group were noted for totalcalories, protein, carbohydrate, fat, or caffeine ingestion.However, significant main effects for time were observed forprotein (p = 0.01) and carbohydrate (p = 0.01) ingestion.Pairwise comparisons revealed a significant increase (p = 0.02)from pre to posttest for protein ingestion and a trend towardsignificantly lower (p = 0.06) carbohydrates ingested atposttest in comparison with pretest in WLS. No significantmain effects for time (p . 0.05) were seen for total caloricintake or caffeine ingestion over the 8-week study period. Nosignificant differences (p . 0.05) between groups wereobserved for WLS, meal replacement, or exercise complianceover the course of the study.

Body Composition

Table 4 displays body mass, fat mass, lean mass, and BF%changes for WLS and PLA. No significant group 3 timeinteractions or main effects for group were observed in any ofthe body composition variables analyzed. A significant maineffect for time was found for changes in fat mass (p = 0.002) andBF% (p = 0.001). Follow-up comparisons, however, revealeda significant reduction in BF% for both WLS (p = 0.03) andPLA (p = 0.004) and a significant decrease in fat mass for just thePLA (p = 0.002) group after the 8-week protocol. No othermain effects for time were noticed.

Fitness Parameters

Table 5 presents changes in fitness parameters for WLS andPLA. No significant group 3 time interactions or main effectsfor group were determined for absolute _VO2 max, benchpress 1RM, or leg press 1RM. Significant main effects for timewere detected for both bench press 1RM (p , 0.001) and legpress 1RM (p , 0.001) with both groups significantlyincreasing upper- and lower-body maximal strength from Preto Post. No main effect for time was observed for absolute_VO2max.

Hemodynamics and Clinical Safety Markers

Table 6 shows hemodynamic and serum clinical safety markersanalyzed in WLS and PLA. A significant group 3 timeinteraction effect (p = 0.048) was observed for fasting GLUlevels. Within-group comparisons from pre to post, however,revealed no significant change over time for WLS (p = 0.22) andPLA (p = 0.10). No significant group 3 time interaction or maineffects for group were found for any other hemodynamic andclinical safety markers. Of particular mention, values closelyapproached significance for resting systolic blood pressure(SBP; G 3 T; p = 0.059). Significant main effects for time werenoted for changes in resting SBP (p = 0.001), whereas within-group analysis showed a significant decrease (p = 0.002) inresting SBP for WLS, while no such change was seen in PLA



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(p = 0.149). An overall main effect for time was found for ALTvalues (p = 0.01), but within-group analysis displayeda significant increase (p = 0.03) in ALT concentrations forPLA (still within clinical norms), whereas WLS experienced nosignificant change (p = 0.127).

DISCUSSION

The primary findings from this study reveal improvements(p , 0.05) in fat mass and body composition and strength inboth groups over the duration of the study suggesting thatthe exercise stimulus provided an adequate training response.Interestingly, a significant within-group reduction for restingSBP (–13.8 mm Hg; p , 0.05) was seen for the WLS groupand when compared to PLA, the interaction effect stronglyapproached significance (p = 0.06). Of additional clinicalrelevance, fasting blood GLU values were found to bestatistically significant (p = 0.048), whereas within-groupchanges showed no statistically significant change in eithergroup. However, the collective pattern of change (increase inPLA and decrease in WLS) did reach significance (Table 6).Both study groups were instructed to ingest daily a meal-replacement supplement and self-restrict their normal dietaryintake in an attempt to facilitate weight loss. From a statisticalperspective, neither group successfully accomplished thistask, although daily caloric intake in the WLS group andPLA did nonsignificantly decrease (3.7 and 1.2 kcal�kg21�d21,respectively), which helps to explain the reductions in fatmass and improvements in body composition reported forboth groups.

The effects of caffeine and EGCG on weight loss have beenwell documented because each has been found to increaseenergy expenditure (5,11,12,24) and markers of lipolysis(5,11,21,24). Specifically, caffeine has been found to stimulatemetabolism through systemically increasing intracellularcyclic adenosine monophosphate concentrations, whichsubsequently increases circulating catecholamine (1,16) andfree-fatty acid concentrations (15). These results wereconfirmed by Bloomer et al. (5) who found the consumptionof a caffeine-laden thermogenic drink to significantly increaseepinephrine and norepinephrine secretion, which coincidedwith a significant increase in metabolic rate. Likewise, EGCGhas been suggested to promote fat oxidation (15) and alterfood digestibility in a manner that purportedly facilitatesweight loss (12). Therefore, it is difficult to explain why thecurrent WLS did not alter body composition when comparedto a placebo condition, although it is possible that optimaldosages or combinations of these nutrients has yet to be fullyrealized. Certainly, a key consideration and limitation of ourstudy was the short nature of our investigation and therelatively small number of subjects per group. Post hoc poweranalysis did reveal that for 2 of 3 of our primary outcomes wemay have been underpowered, but when combined withrelative effect sizes for all of these variables (d , 0.30), it ismore likely that other factors may have contributed to ourinability to yield differences. In this respect, the 8-week study

duration may not have provided an adequate amount of timefor a nutritional intervened group to separate itself from theplacebo. Upon considering that significant improvements inupper- and lower-body strength (Table 5) and overallimprovements in body composition (Table 4) suggest anoptimal exercise stimulus was provided; the lack of change incardiorespiratory fitness (Table 5) is puzzling. To this point,a limitation of this measurement was our inability to test andtrain the study subjects on the same mode of exercise;however, changes in maximal aerobic capacity were not ofprimary consideration and it was more important thatsubjects were able to maintain adequate heart rate levelsthroughout their cardiorespiratory exercise sessions. Asa result, we feel our inability to test and train on the samecardiorespiratory exercise mode do not deflect from ourability to discern changes in our primary outcomes. Of note isthe high rate of participant compliance in terms of ingestingthe meal replacement (WLS: 94.0 6 4.0%; PLA: 97.0 6 1.0%)and assigned supplement (WLS: 91.3 6 5.0% and PLA 93.2 6

5.8%) and adherence to the exercise program (WLS: 100 6

0.0%; PLA: 100 6 0.0%). Furthermore, protein intake of bothgroups was increased (Table 3), which may provide someexplanation for the reported changes in body composition(17). Therefore, although some studies suggest that consum-ing thermogenic supplements are beneficial in catalyzingweight loss in previously sedentary, overweight individuals(3,24), partaking in a structured exercise regimen with addedprotein intake may provide a satisfactory impetus forfavorably altering body composition and fitness parametersas we are reporting in the present investigation. In light of this,Kerksick et al. reported this outcome in a 14-week studyinvolving a 3 d�wk21 exercise program with carbohydraterestricted diets (14), whereas Lockwood et al. (18) havesuggested that ad libitum addition of a meal replacement maybe a satisfactory stimulus for energy intake reduction andweight loss. As such, no clear consensus has been maderegarding the potential synergistic impact of added macro-nutrient intake and regular exercise in previously sedentary,overweight individuals (26).

Of clinical interest is the finding that eight weeks of exercisewith WLS supplementation elicited a favorable increase inSBP compared to the PLA group. Recent data havedemonstrated that caffeine (20) and citrus aurantium (9,13)negatively affect hemodynamic parameters (i.e., increaseheart rate and blood pressure), but results from our studysuggest that when combined with an exercise and supple-mentation regimen these parameters may improve. As such,other literature studies argue that physical activity is effectiveat lowering SBP through a reduction of vascular resistance,sympathetic nervous system activity, and decrease in therenin–angiotensin system (10); thus, it is possible that thiseffect was merely the physiological impetus provided fromthe exercise program. In consideration of these strengths andlimitations, premature interpretations should be made withcaution as longer studies using altered dosing regimens and




exercise programs are needed to more clearly elucidate if thecombination tested in the present investigation is indeedrepresentative of what is expected.

Thermogenic products are increasingly popular for theirability to enhance resting metabolic rate (3,24), stimulate thesecretion of catecholamines (5,6), and increase markers oflipolysis in the form of increased prevalence of serum glyceroland free-fatty acids (11), markers of increased lipolysis. Whencombined with a modest, regular exercise program and a dailymeal-replacement supplement, the addition of a WLS over 8weeks had no further impact over body composition,cardiorespiratory and musculoskeletal adaptations, an effectnot in accordance with some of the available literature (3,24).Of particular interest was the possibility that regularsupplementation and exercise may improve blood GLUvalues and resting blood pressure in those individuals whoconsumed the WLS. Upon considering the short duration ofthe study protocol and relatively small number of subjects, theeffects identified in this study warrant further investigation inhealthy, sedentary and overweight and obese populations. Insummary, the current investigated supplement appears safe asit exerted no adverse effects on hemodynamic parameters (i.e.,heart rate, blood pressure), whole blood and serum healthmarkers (i.e., GLU, TCHOL, HDL, LDL, triglycerides, GGT,AST, or ALT) and self-reported adverse events. When addedin a daily fashion to a regular exercise and diet program, it mayhelp to reduce cardiovascular disease risk as seen by thereduction in serum GLU (p = 0.048) and SBP (p = 0.06) values,but may have little to no additional impact on changes relatedto weight loss, fitness, and body composition changes.

PRACTICAL APPLICATIONS

A popular practice of exercising and dieting individuals is tosupplement a reduced calorie diet with a meal replacement andpotentially to also add an additional thermogenic nutritionalsupplement. Results from the present study suggest that theaddition of a thermogenic to such a regimen provides nofurther benefit related to changes in body mass, bodycomposition or fitness, but may have potential benefitregarding some clinical markers. Considering the interest inweight loss and efforts to modify body composition insubpopulations related to health, body composition andperformance, it is important to research included ingredientsin WLSs and before personal ingestion to determine a product’spotential efficacy and safety. Based on the present results andresults of previous studies, WLSs can be a safe addition to anexercise program purported for weight loss, but the efficacy oftheir addition may not be any greater than slightly restrictingcaloric intake while consuming a daily meal replacement andfollowing a regular comprehensive exercise program.

ACKNOWLEDGMENTS

We would like to thank the subjects that participated in thisstudy. This study was funded by an unrestricted external grantawarded to the principal investigator (CK) by Champion

Nutrition. This study does not indicate endorsement by theNational Strength and Conditioning Association.

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