Fitness, Performance, and Risk of Injury in British Army Officer Cadets

I
Fitness. Military
Perfonnance, and Risk of Injury
changes in relevant measures of fitness; second, to detennine if
OCdts could achieve the required standards on four job-related
military tasks; and third, to assess the relationship between
initial fitness levels and lisk of injury.
Methods
Study Location
The study took place from September 1996 to September
1997 at the Royal Military Academy in Sandhurst, United Kingdom.
Subjects
One hundred six OCdts participated in the study, comprising
68 males (mean age, 22.8 :t: 1.4 years; stature, 1,803 :t: 70 rom;
body mass, 77.9 :t: 8.7 kg) and 38 females (mean age, 23.4 :t: 1.7
years; stature, 1,668 :t: 49 mm; body mass, 65.5 :t: 5.3 kg).
Ethics approval for the procedures was provided by the Univer-
sity of Birmingham. Before the commencement of the study, all
subjects underwent medical examinations and written consent
to participate was obtained.
Physical Training
As part of the 44-week CC program, in addition to other
physically demanding lessons, including military exercises and
drill, there were 93 formal JYr periods of 45 minutes. The total
number of JYr lessons and the programming of those lessons
largely reflected both experienced opinion of what JYr was required
and pragmatic considerations of the time and costs associated
with the entire CC.
The objectives of the JYr program were to develop and maintain
standards of individual fitness. Term I included 38 JYr
periods comprising 6 double lessons and 26 single lessons,
which tended to focus on basic fitness and battle JYr. Term 2
included 26 JYr periods comprising 6 double lessons and 14
single lessons, which focused on endurance training and battle
JYr. Term 3 included 29 JYr periods comprising II double lessons
and 7 single lessons, which concentrated on preparation for the
Sandhurst competitions and the military exercises in term 3.
I The 93 JYr periods were broadly classified as conditioning (8),
! endurance training (mainly marching) (40), battle JYr (mainly
I assault course) (23), basic JYr (mainly gym skills) (13), and swim-
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effort run on a flat bitumen course. For both tests, duration of
running was recorded in seconds.
Muscular strength/power was assessed using three tests.
Static lift strength (SLS) was assessed by the 38-cm upright
pull, as described by Knapik et al.IO This test determines the
composite force produced by the muscles involved in hip and
knee extension and elevation. A Takei dynamometer (Cranlea,
Birmingham, United Kingdom) with liquid crystal display was
used to record force production. One practice attempt and two
maximal efforts were permitted. Maximal force production was
recorded in kilograms. Dynamic lift strength (DLS) was measured
using the incremental lift tesVI to a modified height of
1.45 m (Campden Instruments, Loughborough, United Kingdom).
The initial load lifted (the mass of the carriage alone) was
20 kg. Up to 32 2.5-kgweights could be added to the carriage by
inserting a pin in the weight stack. Increments of 5 kg were used
initially, and 2.5-kg increments were used as the subject approached
maximum. Maximum load lifted was recorded in kilograms.
Back extension strength (BES) was measured using a
custom-made back extension rig with a digital display unit
(Campden Instruments). Subjects stood upright facing the dynamometer
with a yoke around the shoulders and the hips
against a plate. One practice attempt-and two maximal efforts
were performed, and maximal force production was recorded in
kilograms.
Muscular endurance was measured using two tests: abdominal
curls and pull-ups. The maximal duration that a subject
could sustain a progressive sit-up test was recorded in seconds
(National Coaching Foundation, Leeds, United Kingdom). The
maximum number of pull-ups that could be performed on a
gymnasium beam, performed with the chin brought above the
beam on the "up heave" and with the arms at full extension at
the low position, without rest, was recorded.
Percentage body fat (BF) was determined using an electrical
impedance device (Bodystat 1500, Bodystat, Douglas, Isle of
Man). 12-14 Fat free mass (FFM) was determined as the difference
between body mass and fat mass.
Military Tasks
Previous work15 identified standards on four representative
military tasks that British Amy soldiers were required to
ming (8). An additional 7, 10, and 11 periods were used to achieve. The required standards (referred to as levels 1.2. and
undertake assessments of fitness and competitions for terms I,
2, and 3, respectively..
3). which were endorsed by arms and service directorates. varied
by trade. The representative military task protocols comprise
a single lift. a carry. a repetitive lift. and a loaded march. The
Fitness Measurements
single lift entailed progressive maximal lifting of a loaded am-
A battery of tests measuring aerobic fitness, muscular munition box with handles. from the ground to a height of 1.45
strength/power, endurance. and body composition was per- or 1.70 m (depending on trade). The carry involved continuous
formed in the first week of the CC and at the end of each 14-week walking up and down a 30-m course at a prescribed pace of 1.5
term.
m/s. carrying. for as long as possible. two plastic water cans
Aerobic fitness was estimated using a progressive 20-m mul- each weighing 20 kg. The repetitive lift involved lifting a loaded
tistage fitness test (MSFT)9 and a 1.5-mile run. The MSFT in-volved ammunition box with handles. weighing 10. 22. or 44 kg (de-
running back and forth along a 20-m track at a speed pending on trade). from the ground. carrying it 10 m. and lifting
that increased from 8 km/h by 0.5 km/h every minute. Running it to a height of 1.45 m for 10. 15. or 20 minutes. respectively.
speed was indicated by audio signals. OCdts were withdrawnfrom The loaded march involved completing an B-mile flat bitumen
the test when they could no longer continue or failed tokeep course as quickly as possible \\ith a rucksack loaded to 15. 20.
up with the set speed. The 1.5-mile run involved a best- or 25 kg (depending on trade).
Medicine, Vol. 164. June 1999