MILITARY MEDICINE. 172. 2 :121 . 2 0 0 7

Physical Fitness, Training Volume, and Self-DeterminedMotivation in Soldiers during a Peacekeeping Mission

Guarantor; Sindre M. Dyrstad. PhDContrihutors: Sindre M. Dyrstad. PhD; Blake W. Miller, PhD; Jostein Hallen, PhD

Purpose: The goal was to register physical training voiume andto measure changes in physicai fitness in soidiers during apeaceiceeping mission. The relationship between these factorsand motivation for physicai training was also investigated.Methods: Physical training volume was registered and maxi-mai oxygen uptake, 3-kra run time, sit-ups, push-ups, andchin-ups were tested before and after 1 year of service for 71Norwegian soldiers in the international Kosovo Force. Self-determined motivation was measured at the end ofthe service.Resuits: Physical training voiume was 117 ± 77 minutes/week.The average maximal oxygen uptake decreased by 2.5 ± 0.8%(p < 0.01). Intrinsic motivation positively predicted physicaltraining voiume (p < 0.01). Conclusions: A large variation intraining volume was found, and only one-third of the soldiersimproved physical fitness and maintained body weight. Foster-ing intrinsic motivation toward physicai training is key toincreasing training voiume. However, obligatory training couidensure a minimum of physical training among the soldierswho were least motivated for physical training.

Introduction

P hysical fitness is one of the basic military skills required forsoldiers to perform their tasks effectively. Regular physical

training is therefore included in soldiers' obligatory educationalprograms around the world. Physical training facilities in mib-tary camps are also part of the welfare service. To improve thequality of physical training, it is important to evaluate trainingoutcomes and how soldiers exercise. Many studies have evalu-ated the effects of physical training on soldiers" fitness duringdomestic military service, but such studies are missing for in-ternational military missions. Therefore, very little is knownabout the soldiers' physical training habits and how physicalfitness develops in soldiers durtng international peacekeepingmissions.

Motivation is important for health behavior performance andthus, to a great extent, health.' It is postulated that understand-ing motivation is key to the health-promoting etTorts of physicalactivity. To better understand how to increase motivation forphysical training among soldiers, it is important to gain knowl-edge of why soldiers exercise. One ofthe major theoretical ap-proaches in motivation research in sports is self-determinationtheory.^^ Self-determination theory explains that individualscan be motivated for different reasons, which range from high tolow levels of autonomy. Intrinsic motivation represents the mostself-determined motivation and refers to participation in activi-ties for the feelings of pleasure and satisfaction that are deriveddirectly from participation.^ Extrinsic motivation refers to a va-

Norwegian School of Sport Sciences. NO-0806 Oslo, Norway.This manuscript was received for re\1ew iii Septemher 2005. The revised manu-

scripi w;\s accepted for puhlication in July 2006.Reprint & Copyright © by AssociaUon of Military Surgeons of U.S.. 2007.

riety of regulatory styles (i.e.. external and identified regulation)and is characterized by an individual's goal of action beingdirected by an external consequence, such as a reward, benefit.or punishment.'' The least self-determined construct in self-determination theory is amotivation. which represents a lack ofintention and a relative absence of motivation.^ Research hasidentified links between a physically active lilestyle and motiva-tion and has found that individuals who identify training asImportant and see themselves as being physically active alsoidentify themselves as being more intrinsically, rather than ex-trtnsically. motivated.*'** Much ofthe motivation research to datehas been preoccupied with physical education settings and, toour knowledge, physical training in the military is a virtuallyuntapped milieu for investigating self-determined motivationtoward physical training.

The main purpose of the present study was to register thephysical training volume and to measure the changes in phys-ical fitness among soldiers in the international Kosovo Force(KFOR). We also wanted to investigate the relationship be-tween these factors and self-determined motivation for phys-ical training.

Methods

Participants

The participants were 71 male, Norwegian, infantry soldiersfrom one company in the international KFOR. The average age atthe start ofthe study was 20.5 ± 1.8 years. Illness, injury, andleave of absence resulted in 12 dropouts from the tests of max-imal oxygen uptake fV02,,,J and nine dropouts from the mea-surement of self-determined motivation. The body weight andbody height ofthe tested soldiers before the mission were 80.3 ±9,7 kg and 18i.3 ± 7.4 cm. respectively. The study was ap-proved by the regional ethics committee, and written informedconsent was obtained from the soldiers.

Study Design

V0^n,3,. time to exhaustion (TTE). 3-km run time, and maxi-mal numbers of push-ups, sit-ups, and chin-ups were testedbefore the start of military service in Kosovo and before demo-bilization. 1 year later. The amount of all physicai training in asweat suit was registered throughout Ihe service, and self-determined motivation for physical training was measured be-fore demobilization.

Measurements

VOg v arid TTE

VOjma; and TTE were assessed by treadmill running using astepwise incremental protocol with constant incline of 5.2% and

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122 Physical Fitness and Motivation

speed increment of 1 km/hour every 1 minute until volitionalexhaustion. The initial speed for each Individual was chosenaccording to a pretest familiarization trial, to ensure that thecontinuous exercising phase would last 4 to 7 minutes. Theparticipants were encouraged to run as long as possihle, andTTE was measured. Before the test, participants wamied upwith 20 minutes of running, followed by a 5- minute rest.

The participants wore a nose clip and were connected to theergospirometry system (Oxycon Pro; Erich Jaeger, Hoechberg.Germany) via a mouthpiece and a three-way directional valve(Hans Rudolf. Kansas City, Kansas). The Oxycon Pro was cali-brated with room air and certified calibration gases at 180 kPa(5.55% CO, and 94.45% N2). Adequate ventilation ensured thatthe gas concentrations in the laboratory were the same as out-doors, The volume sensor (Triple V; Erich Jaeger) was automat-ically calibrated according lo the manual. Volitional exhaustionwas the main criterion indicating that V02inax was achieved, andthe highest mean VOsn,;, over 1 minute was defined as theV02i,|.,,. In cases in which the subject's exhaustion was in doubt,the following criteria were used to indicate exhaustion: (1) arespiratory exchange ratio (RER) of >1.05, (2) a blood lactatelevel of >6 mmol/L. and (3) a test duration of >4 minutes. Forthe second test, the maximal heart rate (HR^,J was evaluatedagainst ihe HRj . ,, achieved during ihe pretest.

Heart raie (HR) was continuously measured with a HR mon-itor (Polar Paeer; Polar Electro Oy. Kempete. Finland), and thehighest HR during the test was defined as the HR,,, . The bloodlactate level was measured with an enzymatic method fYSI 1500Sport: Yellow Springs Instruments. Yellow Springs. Ohio). Ablood sample was taken from a fingertip 3 minutes after exerciseand analyzed for laciate concentration. The lactate analyzer wascalibrated with a 5 mmol/L lactate standard, and linearity wascontrolled with a 15 mmol/L lactate standard. Calibration wasaccepted when values were within 4.9 to 5.1 mmol/Land 14.0to15,7 mmol/L. respectively.

Body weight was measured by using a digital scale (model708: Seca Corp. Hanover. Maryland), with participants wearingT-shirts, shorts, and socks. Height was measured by using astadiometer (model 708, Seca Corp).

The tests were performed in a mobile test laboratory at sealevel in Norway before mobilization and at --500 m above sealevel in Kosovo before demobilization. No difference in VOa x foruntrained participants has been seen between these altitudes.^To achieve the same ambient temperature inside the laboratoryas in Norway, air conditioning and a camouflage cloth stretchedabove the test container were used in Kosovo.

Standard Military Tests

Aerobic endurance was assessed as the time for a 3-km run.performed outdoors on a level paved surface under similarweather conditions in Norway and Kosovo. Sit ups representeda test of muscular endurance of the tnink and hip fiexors. Thestarting position was a supine position with legs at a box. 90° atthe knees, and held by a partner. The upper body was raised insuch a way that one elbow touched the opposite knee. Push-upsrepresented a test of muscular endurance of the arm. shoulder.and chest. The participants started with straight body, with thechest and cheek touching the floor. The upper body was raiseduntil the arms were straight. Chin-ups represented a test of armand shoulder strength. The starting position was hanging freely

from a bar using an overhand grip, with straight arms and legs.The chin was pulled over the bar. For sit-ups. push-ups, andchin-ups. the maximal number of repetitions was counted.

The results for sit-ups. push-ups, and chin-ups were eachgiven a grade according to military regulations.'" and the meanof these three grades was used as the grade for strength. If allthree before/after tests were not performed, then the averagestrength test grade was based on the number of tests that wereperformed.

Physical Training Registration and Self-Determined Motivation

All 71 soldiers reported their daily physical training on amonthly report form. The monthly response rate was 85 ± 8%.Training volume, frequency, and type of activity were reportedfor all obligatory and voluntary physical training in a sweat suit,Registraiion of training started 45 days after arrival to Kosovoand ended 3 weeks before demobilization. Physicai training vol-ume is reported in minutes per week.

Self-detennined motivation was measured at the end of theservice by using the Situational Motivation Scale (SIMS)." TheSIMS questionnaire identifies four distinct regulation levels ofself-determined motivation, namely, intrinsic motivation, iden-tified regulation, external regulation, and amotivation.

Statistical Analyses and Data Processing

Student's ( test was used to compare means between twosamples for a given variable. One-way analysis of variance withTukey's post hoc tests was used to examine Ihe significance ofdifferences between more than two samples. A bivariate corre-lation analysis with the Pearson correlation coefficient was usedto estimate correlation between two factors.

Power analysis revealed that the reported differences in bodyweight. VOjniax- TTE. and 3-kni run time during KFOR servicegave a power between 87% and 100%. Wiih the number ofsubjects included, we had a power of >80% to report a 2.0%difference in body weight, a 2.2% difi"erence in VOsma . a 5.0%difference in TTE. and a 3.0% difference in 3-km run time, giventhe observed SDs ofthe changes in these variables.

A principle component factor analysis was first conducted forthe SIMS, To examine how the four self-detennined motivationdimensions predicted physical training volume, we conducted asimultaneous multivariate regression analysis, with the fourmotivational dimensions as predictor variables and physicaltraining volume as the criterion variable. After a significantfinding emerged that indicated intrinsic motivation as a signif-icant predictor, we conducted post hoc analyses by creating twogroups, high intrinsically motivated (ri = 25) and low intrinsi-cally motivated (n = 19). based on an extreme median split(±0.25 X SD). To determine whether the groups differed inphysical training volume, a one-way analysis of variance wasconducted. A p value of <0.05 was regarded as statisticallysignificant. Results are presented as mean ± SD or mean ±SEM; SD is used if not otherwise indicated. For the regressionanalyses. B (unstandardized coefficient) and 95% confidenceinten'al are reported.

Results

The average physical training volume during the fmal 9months of service was 117 ± 77 minutes/week, in 1.8 ± 1.2

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Physical Fitness and Motivation 123

sessions. Weekly training consisted of 85 t 70 minutes ofstrength training in 1.3 ± 1.0 sessions and 32 ± 31 minutes ofendurance training in 0.6 ± 0.5 sessions. Forty-three percentof the participants trained >2 hours/week, whereas 28%trained < 1 hour/week. The volume of physical training variedover the year (Fig. 1). During service, the average VOj ^ de-creased 2.5 ± 0.8% (mean ± SEM, p < 0.01) (Tahle I), indepen-dent of initial V02,n; . The SDs of the changes in body weight.VOan, , and TTE were 4.2 kg. 3.2 mL/kg per minute, and 0.8minutes, respectively, There were significant but only minordifferences in HR .,,, RER. and blood lactate level between thebefore and after VOan . tests (198.6 ± 6.6 beats/minute vs.197.2 ± 7.8 beats/minute. 1.09 ± 0.07 vs. 1.12 + 0.07, and8.0± 1.5 mmol/L vs. 8.7 ± 1.6 mmoI/L,p< 0.05, respectively).

A significant correlation was found between training volumeand change in V02T,,ax during Kosovo service (Fig. 2). Trainingvolume also correlated with VOJIH-LV after Kosovo service (r =0.45. p < 0.01, n = 58) but not with VOsinax before Kosovoservice. To study the variation of the change in VOamax- theparticipants were divided into three equal-sized groups accord-ing to the change in yOi^^x in during service. Table 11 showsthese groups' data for VOani x' body weight, and training volume.Group A included the soldiers with the largest decrease in rel-ative VOaniax- group B included the soldiers with the mediumchange in relative VOimax- ^ group C included the soldierswith an increase in relative V02niax- Groiip C had the highesttraining volume and was the only group that maintained bodyweight.

During service, the average 3-km run time increased by 4.8 ±1.0% (mean ± SEM. p < 0.01). and the SD of change was 0.9minutes. There were no changes in the numbers of sit-ups andpush-ups during service, whereas the number of chin-ups in-creased (p < 0.01) (Table III). Training volume correlated withthe average strength test grade (Table III) before (r = 0.27. p -0.043. n = 58) and after (r = 0.35, p < 0.01, n = 59) Kosovoservice.

TABLE 1

BODY WEIGHT. VOJM^X. AND TTE DURING VO^M,^ TEST BEFORE ANDAFTER I YEAR OF MILITARY SERVICE IN THE KFOR

Body weight (kg)VOjn,^ |mL/kg per

minute)VOj ,,, (L/minute)TIE (minutes)

n

5958

5859

Before Mission

80.3 ± 9.755.1 ± 5.0

4.40 ± 4.95.57 i 0.75

After 1-Year Mission

83.1 ± 11.3"53.7 ± 5.9"

4.44 i 5.15,15 ±0.92"

Values are mean ± SD."Significant ( p < 0.01).

A four-factor structure accounted for 73% of the total vari-ance explained by self-determined motivation. The a coefficientsfor the four factors were as follows; intrinsic motivation. 0.78;identified regulation. 0.84: external regulation. 0.83: amotiva-tion. 0.89. Multivariate regression analysis of the four regula-tion levels of self-determined motivation and training volumerevealed a significant overall statistic (R = 0.18. F = 3.08. p =0.023). Furthermore, intrinsic motivation positively predictedphysical training volume ((3 = 35.9: 95% confidence interval,11.7-58.0: n = 62: p < 0.01). No other significant resultsemerged between the other regulations of self-determined moti-vation and physical training volume. No relationship betweenself-determined motivation and V02,,,a.x was found. Post hocanalyses of high and low intrinsic motivation revealed that thehigh intrinsic motivation group trained 141 ± 78 minutes/week. 70% more than the low intrinsic motivation group (p <0.05).

Discussion

The KFOR soldiers completed ~ 2 hours of physical training ina sweat suit per week, and 73% of this training volume wasindividual strength training. Most of the physical training was

250 -,O Enduraoce training

• Strength training

0

Oct Nov Dec Jan Fcb Mar Apr May

Month

Fig. 1. Volume of endurance and strengtli training during 9 months of military service in the KFOR (mean i SD].

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124 Physical Fitness and Motivation

350

-10 J

Average training volume (min-week' )

Fig. 2. Relationship between training volume and change in VO;n^ during 1 year of service in the KFOR (r = 0.46, p < 0.001. n = 58).

TABLED

INITIAL VOjMAX. PERCENTAGE CHANGE IN VOJMAX- BODY WEIGHT. PERCENTAGE CHANGE IN BODY WEIGHT, AND PHYSICAL TRAININGVOLUME DURING KOSOVO SERVICE FOR PARTICIPANTS DIViDED INTO THREE GROUPS ACCORDING TO CHANGE IN VO wx DURING

KOSGVO SERVICE

VOjn^ before mission (mL/kg per minute)Percentage change in VO^,^,,^VOamas before mission (ml,/minute)Percentage change in VO.^,,^Body weight before mission (kg)Percentage change in body weightPhysical training volume (minute/week)Endurance training (minute/week)Strength training (minute/week)

Group A (n = 20)

53.9 ± 6.3-8.3 ± 2.94398 ± 540-2.8±4.1'''=82.3 ± 12.56.3 ± 5.0''77 ± 48"31 ± 2246 ± 35"

Group B (n = 19)

56.4 ± 3.8-2.9 1 1.1' "4366 ± 65

1.4 ±3.177.6 ± 8.54.5 ±3.1"136 ± 8027 ±23

109 ± 78

Group C(n= 19)

55.0 ± 4.34.2 ± 4.0"-''

4440 ± 1613.5 ± 4.3"

80.9 ± 7.1-0.4 ± 3.5^169 ± 7648 ±46

121 ± 71

Values are mean ± SD."Significantly diilerent from the other groups (p < 0.01).'Significant change during mission (p < 0.01).'Signiiicantly different from the other groups (p < 0.05).

voluntary, and the variation in training volume was large.VOmax ^"d the average grade for sit-ups, push-ups, and chin-ups correlated with physical training volume. The soldierswith the largest decrease in VO niax carried out less thanone-half of the training volume of the group with an increasein VOa,,,,,. . Soldiers reporting high intrinsic motivation re-ported higher training volume than did those reporting lowintrinsic motivation.

There is no regulation prescrihing ohligatory physical train-ing for Norwegian soldiers during international missions. Mil-itary tasks are the main priority but. if possible, the regula-

tions for domestic service are followed. These regulationsindicate a minimum of 2 hours of physical training in twosessions per week. In the present study, physical training wasregistered from September to June. A mean of 2 hours ofphysical training per week was carried out only in Januaryand February, when the soldiers had few military tasks. FromSeptember to December, the Norwegian force carried outmany military missions, which resulted in a mueh lowertraining volume, compared with January and February. Be-cause of a riot in Kosovo in March, military activity increased,and the average training volume in March and April decreased

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Physical Fitness and Motivation 125

TABLEm

RUN TIME. MEAN NUMBER OF REPETITIONS FOR SIT-UPS.PUSH-UPS, AND CHINS-UPS. AND AVERAGE STRENGTH TEST

GRADE BEFORE AND AFTER 1-YEAR KOSOVO SERVICE

Exercise Test

3-km run time[minutes)

No. of sit-upsNo. of push-upsNo. or chin-upsAverage strength test

grade''

n48

49514651

Before Mission

12.74 ± 1.10

44 ± 2 833 ± 14

5.0 ± 3.53.0 ± 1.2

After 1-Year Mission

13.35 ± 1.43"

43 i 1534± 11

6.9 ± 3.9"3.3 ± 1.2"

Values are mean ± SD."Significantly different (p < 0.01).''Based on the results for sit-ups, push-ups, and chin-ups.

by 34%. compared with January and February. Because aer-obically trained individuals, compared with untrained indi-viduals, seem to have a reduced psychosocial stress re-sponse.'^ cope more effectively with emotional stress.'-""'andrespond to acute stress with superior motor performance. ' itis important that soldiers are aerobically fit during intensive.high-stress periods. Increasing physical training in periodswith low military activity is therefore important to maintain orto increase physical fitness. Because exercise may also havebeneficial effects on sleep,'^ maintenajice of physical trainingduring intensive periods could be of importance for soldierswith sleep problems,

Although there were many possibilities for endurance train-ing in the camp. 73% of the physical training volume wasstrength training. Muscles seemed to be part of the soldiers'image, and the motivation to increase muscle strength andvolume exceeded the motivation to improve endurance. In thestudy by Biddle and Bailey.' men indicated more motivation forskill development, whereas women expressed greater social ori-entation. Fredrick et al.'* found that men involved in fitnessactivities were motivated to participate to improve body appear-ance and that body-related motivation directly predicted fre-quency of exercise. Rapid skill development and improved bodyappearance, achieved during strength training, may thereforeexplain why the soldiers preferred strength training.

As opposed to sit-ups and push-ups, an increase in the num-her of chin-ups during Kosovo service was found. The soldiers inthe present study were also tested during their 1 year of militaryservice before Kosovo service, but no improvement in chin-upswas found during that service period.'^ The muscle groups in-volved in chin-ups need to be trained with fewer repetitions andheavier load, compared with the muscle groups involved inpush-ups and sit-ups. Heavier strength training and more focuson the chin-up exercise during KFOR service may thereforeexplain this improvement.

There was no significant correlation between physicaltraining volume and the changes in the average grade for thestrength tests. This could be attributable to the fact that thephysical training volume during Kosovo service correlatedwith both before and after strength test grades. This indicatesthat the soldiers who trained most during Kosovo service werealso the strongest soldiers before service; therefore, their po-tential for improvement was less than for those with lowertraining volumes.

The average reduction in VOj ax during 12 months in Kosovowas 2.5 ± 0.8% (mean ± SEM. p < 0.01). This reduction couldbe a reason for the reduced performance in the 3-km runningtest and the reduced TTE during the VOaniax test. There were onlyminor differences in the physiological parameters of HR, bloodlactate level, and RER. indicating that the subjects' efforts toachieve the best possible test results were similar during thebefore and after tests. A similar reduction in V0;2inax was foundfor the same soldiers during their 6 months of Norwegian mili-tary service before the Kosovo service.'^ However, the physicaltraining volume was much higher during the military service inNorway and included 3 to 4 hours/week of vigorous physicalactivity, such as marching with a backpack, battle training, andmovement in rugged terrain. These activities were performed inuniform, mostly at low intensity. During the Kosovo service,most such acti\1ties ended and almost all transportation was byvehicle. However, the decrease in low-intensity training volumedid not lead to a more-rapid decrease in VOamax. which could beattributable to the fact that the amounts of physical training ina sweat suit were very similar before and during service inKosovo. This physical training was normally carried out athigher intensities than vigorous physical activity in uniform.According to several studies, high training intensity is crucialfor improving VOan; , * " ^ and a 60 to 70% reduction of trainingvolume may not reduce VOanm as long as the training intensityis maintained. ^• ''

The variations in hoth training volume and changes in V02,naxwere large. The soldiers with an increase in VOj , , (Table II)performed more than twice the training volume, compared withthose with the largest decrease in VO-im^^. There was no signifi-cant difference in the endurance training volume, but group Chad a much higher strength training volume than group A.Improvement in VOj,, ,., as a result of most forms of resistancetraining is unlikely to occur in aerobically trained and untrainedindividuals. ' ^ The lone exception to this seems to be circuitweight training, which was not a common strength trainingmethod among these soldiers. There was no significant difler-ence in hody weight among the three groups before the Kosovoservice. However, the soldiers who increased their VOamaN werethe only soldiers who maintained their body weight during the1 -year period. The improvement in relative VOjma., (milliliters perkilogram per minute) in this group was therefore attributable tothe 3.5 ± 1,0% (mean ± SEM. p < 0.01) increase in absoluteVO niax (liters per minute). The soldiers in group A had thelargest increase in body weight, and this group was the onlygroup with a decrease in absolute VOamax- Group A also had thelowest training volume, indicating that the increase in bodyweight was probably attributable to an increase in hody fat.rather than musculature. A reduced level of vigorous militaryactivity in unifomi during the peacekeeping mission could bepart of the explanation for why these soldiers gained more bodyweight during the KFOR mission, compared with their earliermilitary service.

Body weight is affected by energy intake and energy expendi-ture. Because no significant correlation between physical train-ing volume and change in body weight was found, it could heassumed that those who trained the most were also most awareof their diet. Increased motivation toward a healthy diet, as well

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126 Physical Fitness and Motivation

as good exercise habits, is therefore important for improving ormaintaining the soldiers" fitness.

Of the four different regulatory styles in the SIMS, onlyintrinsic motivation toward physieal training was found topositively predict physical training volume. A 70% highertraining volume was found in the high intrinsic motivationgroup, compared with the low intrinsic motivation group.These findings suggest that an important factor in increasingtraining volume is to increase intrinsic motivation towardtraining, especially when most ol' the physical training Isvoluntary or individual, as in this study.

Intrinsic motivation is entirely connected to the individualneeds of autonomy, competence, and relaledness.'' Althoughresearch is lacking from within a more-regulated environment.such as a military setting, it is argued that creating an environ-ment that values these indi\idual needs will increase the sol-diers' intrinsic motivation toward physical training. Researchamong both youths and physical education students has indi-cated that allowing more autonomy in choosing the types ofphysical activities in which to participate may increase intrinsicmotivation toward exercise, ''• ' Moreover, it is proposed thatenjoyment may be a factor in increasing intrinsic motivation. ''Also, the need for competence leads people to seek tasks that arechallenging within their capacities,^ 11 soldiers experience anenvironment that highlights skill and competence development.then this may iniluence intrinsic motivation toward physicalacti\ity, Relatedness refers to feeling connected to others andha\1ng a sense of belonging, both with other individuals andwith one's community.--' Obligatory joint physical training ses-sions could contribute to team building and increase the espritde corps and. ibrough this, also increase soldiers" intrinsic mo-tivation to exercise.

More obligatory physical training could, at least in the shortterm, increase extrinsic motivation and lead to an increasedtraining volume. However, it has been hypothesized that ex-ternal regulation may have negative consequences, such asthe feeling of pressure, anxiety, and lack of enjoyment of theexercise regimen.*^ ' leading some people to abandon exerciseentirely. However, the soldiers in the present study chosemilitary service, where fitness is emphasized as an essentialquality, over community service: therefore, it is possible thatthese soldiers were already intrinsically motivated towardphysical training before enlisting and this carried over intothe military setting. Furthermore, whereas intrinsically moti-vated people feel comfortable in an autonomous environment,externally motivated individuals are likely to thrive in more-structured environments,'' It is possible that, under certaincircumstances, externally motivated soldiers may participatein obligatory physieal training without negative motivationaloutcomes.

Conclusions

Most of the physical training during Kosovo service was vol-untary or individual strength training, The variations in physi-cal training volume and physical fitness were large, and one-third of the soldiers managed to improve their aerobic fitness.Because soldiers who reported high intrinsic motivation alsoreported higher training volume, compared with those who re-ported low intrinsic motivation, fostering intrinsic motivation is

key to increasing voluntary physical training in the long term.To ensure a minimum of physical training for all soldiers, oblig-atory physical training should be organized. However, obligatoryphysical training should be carried out witbin a context thatemphasizes autonomy, competence, and relatedness andshould focus on endurance training, to provide variability intraining activities.

Acknowledgments

We thank Dr. Pierre-Nicolas Leiiiyre lor usel'ul comments on the article.We also acknowledge Capt SUg HjcUset and Anders Aandstad for help withdata rolleclion and Jennifer Amcsen for English revision of the article.

The study was funded by the Norwegian School of Sport Sciences/Defense institute.

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Letters to the Editor

To the EditorI read with interest, the detailed article by MajorRichard Malish |Milit Med 2006.171 (3): 224-227| describing his experiences of medical carewith the 250''' Forward Surgical Team (Airborne)during a military operation into NorthetTi Iraq in2003. We have used his informative article as avaluable plantiing tool for our own currentoperations in Southern Afghanistan.

As senior surgeon in the FST of 23 Air AssaultSquadron (the successor to 23 Parachute FieldAmbulance). 1 must take exception however atthe following lines in the article: "The jump washistoric because of the inclusion of the FST. TheFST became the first such team to perform acombat jump since World War 11. " This isincorrect!

On 5 November 1956. an FST from 23 ParachuteField Ambulance jumped with the ThirdBattalion. The Parachute Regiment into El GamilAirfield in Egypt as part of Operation Musketeer- The occupation of the Suez Canal Zone, Major(later Major-General) Norman Kirby was thesenior stirgeon. This event is vividly described in'Airborne to Suez' by Sandy Cavanagh who as aLieutenant was the Regimental Medical Officerto 3 Para. He was himself wounded in the eye byshrapnel during the drop. The operation itselfwas a miiitary success with all intendedobjectives being achieved. International politicalpressure later led to the force being withdrawn.Overall. 660 men took part in the drop.

U Col Paul J. Parker FIMC FRCSEd RAMC

To the EditorI read with interest the data in Letters to theEditor. \Milit Med 2006, Voi 171 (6):v-vilpresented by DiNicola and colleagues regardingsmoking behavior among enlisted miiitarypersonnel during deployment and their call foropportunities to participate in efiective smokingcessation programs. I would like to further thismessage by focusing on another importantgroup, namely US veterans with coronary heartdisease (CHD).

Quitting smoking is essential for patients withCUD. Current guidelines recommend thatclinicians ask about tobacco use and providecounseling about quitting within the context of acomprehensive plan for secondary prevention.Nevertheless, smoking remains widespreadamong persons with CHD.

Using data from the 2005 Behavioral Risk FactoiSurveillance System, a state-based surveillancesystem that collects data on U.S. aduits (age>18years), the prevaience of smoking was estimatedfor adult veterans with CHD. A description ofthe design and sampling procedures is availableat www,cdc.gov/brfss. Veterans were identifiedby an afi'irmative response to the question,"Have you ever served on active duty in theUnited States Armed Forces, either in the reguiarmilitary or in a National Guard or militaryreserve unit?" Surveyed adults were asked, "Hasa doctor, nurse, or other health professional evertold you that you had a heart attack, also called amyocardial infarction?" Those who respondedaffirmatively were considered to have CHD.(Continued on P.146)

Military Medicine, Vol. i72, Februaiy 2007