Page 135 - Journal of Special Operations Medicine - Spring 2015

Figure 1 Association between
injuries and fitness in two
studies of infantry Soldiers.

Note: Q, quartile.

Two­mile run performance is used to measure aerobic The relationship between injuries and fitness extends
fitness because it is highly correlated or related to the beyond the military to other physically active occupa­
.
.
19
maximal oxygen uptake (Vo max). Vo max is the gold tional groups. For example, Figure 3a and 3b shows the
2
2
standard for aerobic fitness. It is the highest rate at which relationship between injuries and 1.5­mile run times,
oxygen can be taken up and used by the body during and injuries and push­up performance among Federal
longer­term exercise. It is measured as the milliliters of Bureau of Investigation new agent trainees at Quantico,
oxygen taken up for each kilogram of body weight dur­ Virginia. Although there was no dose­response relation­
ing each minute of activity (mL/kg/min). The faster the ship in most cases, it is clear that those who were least
rate at which oxygen can be used, the faster the rate at fit were more susceptible to injury. 22
which energy can be produced and the faster that long­
20
term activity, like running, can be performed. In one These studies show that there is an association between
.
basic combat training (BCT) study, Vo max was directly injuries and fitness, but they do not necessarily show
2
21
associated with injury incidence, as shown in Figure 2. that low fitness causes higher injuries. A study con­
.
The higher the Vo max on arrival for training, the lower ducted in BCT showed that increasing fitness directly
2
23
the injury risk during training. In this case, trainees were reduced injury risk. Two groups of Soldiers with very
separated into tertiles of fitness, groups each represent­ low performance on push­ups, sit­ups, and a 1­mile run
ing 33% of the unit. were identified prior to BCT. One group received a stan­
dardized preconditioning physical training program for
Figure 2 Association between maximal oxygen uptake up to 3 weeks before entering BCT; the other group just
.
(Vo max) and injury incidence in basic combat training. entered BCT immediately without any fitness training.
2
Figure 4 shows that those involved in the precondition­
ing program had a lower injury incidence during train­
ing compared to those who did not have the opportunity
to do the preconditioning program. 23
Why are those who are more fit less likely to get injured?
Soldiers perform many physical tasks, like road marches;
preparing fighting positions; filling and emplacing sand­
bags; constructing emplacements; loading and unloading
trucks; casualty evacuation; erecting camouflage; moving
over, through, and around obstacles; and land navigation.
Individuals with higher levels of fitness perform these

Physical Fitness for Injury Prevention 125