A TRAINING PROGRAM TO IMPROVE
NEUROMUSCULAR AND PERFORMANCE INDICES
FEMALE HIGH SCHOOL BASKETBALL PLAYERS
IN
FRANK R. NOYES,1 SUE D. BARBER-WESTIN,1 STEPHANIE T. SMITH,1 THOMAS CAMPBELL,1
2
AND TIINA T. GARRISON
1
Cincinnati SportsMedicine Research and Education Foundation, Cincinnati, Ohio; and 2Department Health and Human
Performance, Northwestern State University and American Musculoskeletal Research Institute, Alexandria, Louisiana
ABSTRACT
Noyes, FR, Barber-Westin, SD, Smith, ST, Campbell, T, and
Garrison, TT. A training program to improve neuromuscular and
performance indices in female high school basketball players.
J Strength Cond Res 26(3): 709–719, 2012—The purpose of
this study was to determine if a sports-specific training program
could improve neuromuscular and performance indices in
female high school basketball players. We combined components from a published anterior cruciate ligament injury
prevention program for jump and strength training with other
exercises and drills to improve speed, agility, overall strength,
and aerobic conditioning. We hypothesized that this sportsspecific training program would lead to significant improvements in neuromuscular and performance indices in high school
female basketball players. Fifty-seven female athletes aged
14–17 years participated in the supervised 6-week program,
3 dwk21 for approximately 90–120 minutes per session. The
program was conducted on the basketball court and in weight
room facilities in high schools. The athletes underwent a video
drop-jump test, multistage fitness test, vertical jump test, and an
18-m sprint test before and upon completion of the training
program. All the subjects attended at least 14 training sessions.
After training, a significant increase was found in the mean
estimated V_ O2max (p , 0.001), with 89% of the athletes
improving this score. In the drop-jump video test, significant
increases were found in the mean absolute knee separation
distance (p , 0.0001) and in the mean normalized knee
separation distance (p , 0.0001), indicating a more neutral
lower limb alignment on landing. A significant improvement was
found in the vertical jump test (p , 0.0001); however, the effect
size was small (0.09). No improvement was noted in the sprint
test. This program significantly improved lower limb alignment
Address correspondence to Sue D. Barber-Westin, [email protected].
26(3)/709–719
Journal of Strength and Conditioning Research
Ó 2012 National Strength and Conditioning Association
on a drop-jump test and estimated maximal aerobic power and
may be implemented preseason or off-season in high school
female basketball players.
KEY WORDS drop-jump, ACL, lower limb alignment
INTRODUCTION
T
he sport of basketball is demanding and requires
speed, agility, upper and lower body strength,
maximal aerobic power, and aerobic endurance.
Basketball is a popular sport in the United States.
At the high school level, 556,269 boys and 456,967 girls
participated in this activity during the 2006–2007 academic
year (9). Unfortunately, the benefits of playing may be offset
with injuries, and female athletes appear to be at a greater risk
than male athletes are (1,9). Specifically, Agel et al. (1)
reported a significant difference in the rate of noncontact
anterior cruciate ligament (ACL) ruptures over a 13-year
period (1990–2002) between female and male collegiate
basketball players (0.16 and 0.04 injuries per 1,000 exposures,
p , 0.01). Hootman et al. (25) also reported a difference in
the ACL injury rate over a 16-year period between female
and male athletes involved in collegiate basketball (0.23 and
0.07 per 1,000 athlete exposures, p not available).
To our knowledge, only 1 investigation assessed the effects
of a neuromuscular retraining program (Sportsmetrics,
Cincinnati Sportsmedicine Research and Education Foundation, Cincinnati, OH, USA) in reducing the rate of
occurrence of ACL injuries in female high school basketball
players (23). The study included 84 female participants who
completed the training program, 189 female participants
who did not undergo training, and 225 male control players.
The number of player exposures was 4,767 for the trained
female group, 10,370 for the female control group, and
13,039 for the male control group. Four noncontact ACL
injuries occurred in the female control group, compared
with none in the other 2 groups. Untrained female players
had significantly more noncontact knee ligament injuries
than did the male players (p = 0.03).
VOLUME 26 | NUMBER 3 | MARCH 2012 |
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Basketball Neuromuscular Training Program
Figure 1. The landing phase of the drop-jump video screening test. The absolute centimeters of distance between the hips, knees, and ankles are shown on the
left of the stick figures, whereas the normalized knee and ankle separation distances are shown on the right. Top, before training, this 16-year-old basketball player
demonstrated a 37% normalized knee separation distance, with a notable valgus lower limb alignment. Bottom, after training, she had a markedly improved 83%
normalized knee separation distance and a more neutral lower limb alignment.
Many basketball training programs have been developed to
improve player fitness and skill and hypothetically prevent
injuries (10,13,17,18,26,31,33,34,43,44). Investigations vary
considerably in the selection of subjects, duration of training,
exercises and drills performed, and outcome measures. Only
one study to date assessed performance indices in female
basketball players using the Sportsmetrics training program
(44). A small group of female collegiate basketball players
obtained significant improvements in hamstring peak torque
(p = 0.008), which were not found in the control group of
players. Development of hamstrings strength is believed to be
one important factor in preventing knee ligament injuries in
female athletes (2,21,40).
We initiated Sportsmetrics neuromuscular training for
female athletes involved in a variety of sports 15 years ago (23)
and noted occasional problems with player compliance with
the program. The training consisted of a dynamic warm-up,
jump training, strength training, and flexibility. Over time,
players and coaches requested that the program be modified
to include additional sport-specific exercises and drills
designed to improve speed, agility, strength (upper extremity,
lower extremity, and core), and aerobic conditioning. In
710
the
addition, other investigators noted that improved compliance with injury prevention training programs would most
likely occur if the programs target performance enhancement
and neuromuscular retraining (3,27). Therefore, to increase
player compliance and participation, we developed sportsspecific programs for competitive female high school players
involved in basketball (5), soccer (5), lacrosse, volleyball (36),
and tennis (4). These training programs included the essential
Sportsmetrics neuromuscular retraining principles previously
proven to decrease the rate of noncontact ACL injuries in
female athletes, along with other sports-specific exercises and
drills. All the athletes who participated were enrolled in
prospective studies in which neuromuscular and performance indices were measured before and upon completion of
the training program.
For basketball, analysis of games demonstrate the importance of endurance, muscular strength and power, sprint
speed, agility, and jumping ability (14,32). The goal of this
study was to determine if the Sportsmetrics basketball
training program was effective in improving neuromuscular
and performance indices, thereby allowing recommendation
for the program from both an injury prevention and
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TABLE 1. Sportsmetrics basketball training program.
Time
session no.
Week 1,
no. 1–3
Jump training
Wall jump (20 s)
Tuck jump (20 s)
Agility training
Acceleration, speed,
aerobic training
Ladders, reaction
training, dot jump drills
Shuttle drill
Maze drill
Mountain climbers
Sprint-back pedal
Ladder: high knees
High knee ball toss
over barrier
Dot drill: double leg
jumps
Squat jump (10 s)
Week 2,
no. 4–6
Week 3,
no. 7–9
Week 4,
no. 10–12
Week 5,
no. 13–15
Week 6,
no. 16–18
Barrier jumps (20 s each)
Side-to-side
Forward-backward
180° Jump (20 s)
Broad jump (5 repetitions)
Bounding in place (20 s)
Same as in sessions 1–3,
add 5 s to each jump
Add 5 repetitions to
broad jump
Suicides
Tip drill
Mountain climbers
Figure 4 drill
Sprint-back pedal
Wall jump (25 s)
Square drill
Suicides: forward/
backward
Mountain climbers
Tuck jump (25 s)
Triple broad into vertical
jump (5 repetitions)
Squat jump (15 s)
Barrier hops (25 s each)
Side-to-side
Forward-backward
Single-leg hop (5 repetitions)
Scissors jump (25 s)
Bounding for distance (1 run)
Same as in sessions 7–9,
add 5 s to each jump
Add 3 repetitions to triple
broad into vertical jump
4 Dot drill
Quarter eagles
Quarter eagle sprints
Suicides: defensive
slides
Defensive
slides
Shoot and
sprint
Mountain climbers
Wall jump (20 s)
Step, jump up, down,
vertical (30 s)
Squat jump (25 s)
Mattress jumps (30 s each)
Side-to-side
Forward-backward
Triple single-leg hop, stick
(5 repetitions each leg)
Jump into bounding (3 runs)
Same as in sessions 13–15
Add 5 repetitions to step,
jump up, down, vertical
Add 1 run to jump into
bounding
Tip drill
Irish ‘‘D’’
T-drills:
5-10-5
Kill the grass
Sprint with ground
touches
Full court relay
Ladders: up-up,
back-back
Double high knee
with ball toss
Dot drills: add
split leg jumps
Ladders: outside
foot in
Bleacher jumps
Dot drills: add 180°
split leg jump
Ladders: in-in,
out-out
Instructor pointing
Sprint, quick feet
Dot drills: add
single-leg hops
Ladder: scissors
Instructor pointing
with quick feet
up/down
Dot drills: all jumps
Mountain climbers
Ladder: Icky shuffle
Sprint 360
Single-leg squat
jumps and 180°
scissor jumps
Dot drills: all jumps
Mountain climbers
Sprint 180
Power rebounds
relay
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Basketball Neuromuscular Training Program
TABLE 2. Results of the sportsmetrics basketball training program.*
Test
Drop-jump test
Absolute knee separation
distance (cm)
Normalized knee separation
distance (%)
Multistage fitness test
(V_ O2max, mlmin21kg21)
Vertical jump (cm)
18-m Sprint (s)
Pretrain†
Posttrain†
Difference†
p Value
Effect size
18.5 6 7.4
9.2–44.8
CI: 16.5–20.4
44.9 6 17.2
23.0–104.0
CI: 40.3–49.5
34.6 6 4.5
19.6–45.2
CI: 33.4–35.9
26.2 6 12.3
7.0–48.3
CI: 22.9–29.5
3.54 6 0.30
3.02–4.47
CI: 3.46–3.62
31.8 6 10.36
13.2–57.3
CI: 31.2–34.5
74.2 6 18.8
43.0–125.0
CI: 69.1–79.3
39.5 6 5.7
23.8–57.5
CI: 38.0–41.1
28.5 6 12.0
9.5–48.3
CI: 25.3–31.7
3.53 6 0.42
2.38–4.83
CI: 3.41–3.64
13.2 6 11.8
29.5 to 39.4
,0.0001
0.59
29.2 6 26.2
226.0 to 90.0
,0.0001
0.63
4.9 6 4.6
22.8 to 22.0
,0.0001
0.43
2.3 6 3.4
26.3 to 9.5
,0.0001
0.09
20.01 6 0.29
20.70 to 0.70
NS
0.01
*NS = not significant; CI = confidence intervals.
†Mean 6 SD, range, 95% CI.
performance enhancement standpoint. We hypothesized
that this program would improve lower limb alignment on
a drop-jump test from a valgus to a more neutral alignment,
enhance estimated maximal aerobic power (V_ O2max),
increase vertical jump height, and improve sprinting speed
in high school female basketball players.
METHODS
Experimental Approach to the Problem
This study was undertaken to determine if a sports-specific
training program could improve neuromuscular and
performance indices in female high school basketball
players. A program was devised, which used the dynamic
warm-up,
jump
training,
strength training, and flexibility
components from a previously
published ACL injury prevention program (5), along with
new exercises and drills to
improve speed, agility, overall
strength, and aerobic conditioning. A battery of tests was
conducted to determine the
effectiveness of this training
program in improving lower
limb alignment on a drop-jump
test, estimated V_ O2max, vertical
jump height, and sprinting
speed. Improved lower limb
alignment while landing on
a drop-jump test is believed by
others to decrease the risk of
occurrence of a noncontact
ACL injury (24), although
Figure 2. There was a significant difference in the distribution of athletes in the normalized knee separation
V_ O2max, vertical jump height,
distance categories in the video drop-jump test before and after training (p , 0.0001). The category of ,60%
and sprinting speed are essential
indicates a distinct valgus lower limb alignment (Figure 1, top), whereas .80% represents a neutral alignment.
components of this sport.
712
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pathology, symptoms of pain,
patella instability, or a visible
knee joint effusion.
Procedures
Video Drop-Jump Test. A video
drop-jump test was done as
previously described in detail
(6,36). The subjects performed
a drop-jump sequence by first
jumping off a box 30.48 cm in
height, landing, and immediately
performing a maximum countermovement vertical jump. No
specific instructions were provided regarding how to land or
jump; the subjects were only
instructed to land straight in
Figure 3. A significant difference was found in the multistaged fitness test in the distribution of athletes in the
categories shown before and after training (p , 0.0001). The poor category indicates ,31.0 (V_ O2max: milliliters per
front of the box. This sequence
kilogram per minute), the fair category ranges from 31 to 34.9, the good category ranges from 35.0 to 38.9, and the
was repeated 3 times. Three
excellent/superior category indicates $39.0.
images were captured that represented the preland, land, and
take-off phases. The absolute
The athletes who participated in this study were high school
centimeters of separation distance between the right and left
female basketball players. All the subjects underwent a video
hips, knees, and ankles was measured, and the distance
drop-jump test, a multistage fitness test (MSFT), a counterbetween the knees and ankles was normalized according to the
movement vertical jump test, and an 18-m sprint test before the
hip separation distance (Figure 1). The data were also
neuromuscular training program was initiated. The subjects
distributed into 3 categories for analysis: #60% normalized
then participated in the program 3 sessions per week on
knee separation distance, 61–80%, and .80%. The reliability of
Mondays, Wednesday, and Fridays for 6 weeks. The sessions
the drop-jump test has been reported previously (36). For the
lasted approximately 90–120 minutes and consisted of
test-retest and within-test trials, the interclass correlation
a dynamic warm-up, jump training, strength training, speed,
coefficients (ICCs) for the hip, knee, and ankle separation
and agility drills specific for basketball and flexibility. All the
distances were all $0.90.
training sessions were supervised by certified Sportsmetrics
Multistage Fitness Test. V_ O2max was estimated using the
instructors and were conducted on the schools’ basketball
MSFT
(30,38). The subjects were required to perform
court and weight room facilities during the summer off-season
a
shuttle
run back and forth along 20 m, keeping in time with
or in the fall just before the start of their season. The subjects
a
series
of signals on a compact disk by touching the
underwent all of the previously described tests within 1 week of
appropriate
end line in time with each audio signal. The
conclusion of the training program in an identical manner as
frequency
of
the audible signals (and hence running speed)
that done before the training program was initiated. All the
was
progressively
increased until the subjects reached
subjects participated in their high school basketball season
volitional
exhaustion
and could no longer maintain pace
upon the completion of the training program.
with the audio signals. V_ O2max was estimated using
regression equations described by Ramsbottom et al. (38).
Subjects
The test-retest reliability of the MSFT has been reported by
All testing and training procedures were fully explained, and
others to be sufficient, with ICCs $ 0.90 (20,30,45). The data
written informed parental consent was obtained for each
were also placed into categories of poor, fair, good, and
subject. The study was approved by an Internal Review Board
excellent/superior of the estimated V_ O2max for female
for use of human subjects. A total of 57 female basketball
participants aged 13–19 years as determined by the American
players (14–17 years of age; height, 170.8 6 7 cm, range,
College of Sports Medicine (19). The categories indicated by
160–188 cm; weight, 60.7 6 10.1 kg, range, 51.6–72.5 kg;
poor represent ,31.0 estimated V_ O2max; fair, 31.0–34.9;
mean body mass index 20.3 6 3.4, range, 17.2–30.3)
good, 35.0–38.9; and excellent/superior, $39.0.
voluntarily participated in this study. None of the subjects
Vertical Jump Test. The subjects’ countermovement vertical
had participated in a formal neuromuscular or resistance
jump was measured using a Vertec Jump Training System
training program, but all had at least 1 season of experience.
(Sports Imports, Columbus, OH, USA). First, the standing
There were no athletes with a history of knee injury or
VOLUME 26 | NUMBER 3 | MARCH 2012 |
713
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Journal of Strength and Conditioning Research
Study
Lim (31)
TM
McLeod (33)
Vescovi (43)
Kato (26)
Population
Program
Factors
analyzed
Results
22 Female high school players;
Experimental group: ACL injury
15–17 y of age; 11 experimental,
prevention program
11 control
Rebound jump task: 3D motion
Experimental group significant
analysis, force plate,
improvements knee flexion
electromyography data analysis
angle, lower extremity
strength pre-post training
20-min warm-up, 8 wks, before team
Experimental group significantly
practice
different from control group:
knee flexion angle, knee
separation distance, knee
valgus moment, extension
torque, hamstring/quadriceps
ratio
Flexibility, strengthening, plyometrics,
agility, alternative exercises for
warm-down
Control group: regular warm-up
50 Female high school players;
Experimental group: ACL injury
2 Balance tests: BESS for static Experimental group fewer errors
14–17 y age; 27 experimental,
prevention program
balance, SEBT for dynamic
on BESS than control group
23 control
90 min, 23 per week for 8 wks during
balance.
Experimental group significantly
preseason
greater SEBT reach
distances (anteromedial,
lateral, posterior directions)
than control group
Warm-up, functional strengthening,
plyometrics, agility training, balance
training
Control group: regular preseason
practice
No significant differences
Countermovement jump: height,
Experimental group: Sportsmetrics
20 Female collegiate intramural
between groups pretest and
vertical ground reaction force,
ACL prevention program,
players; 18–21 y age;10
posttest all variables
jump power, jump velocity on
plyometrics portion only
experimental, 10 control
45–60 min, 3 dwk21 for 6 wks
portable force plate
8/10 Experimental group
reduced vertical ground
reaction forces (mean 478.8
6 325 N).
Both groups participated in intramural
games during study
Significant differences between
20 Female collegiate players; aged Experimental group: ACL injury
Jump shot: alignment angle of
groups coronal plane and
19–21 y; 10 experimental, 10
prevention program
coronal plane (valgus), knee
torsion angles
control
flexion angle, torsion angle of
horizontal plane using 3 digital
video cameras
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Basketball Neuromuscular Training Program
714
TABLE 3. Published basketball injury prevention training programs for female athletes.*
20 min, 3 dwk21 for 4 wk
Chappell and
Limpisvasti
(10)
Emery (17)
12 Female collegiate basketball
players; 18 female collegiate
soccer players; aged 19 6 1.2 y
5 Exercises for alignment control
during deceleration, balance
exercises on BOSU device
1-h Verbal instruction ACL injury
prevention before first training
session
Both groups practiced 3 dwk21
during study
ACL injury prevention warm-up
program
10–15 min, 6 dwk21 for 6 wks
Drop jump, vertical stop jump on
force plate
Vertical jump height, single-leg
timed hop
No significant reduction from
training in lower extremity or
ankle injuries
Compliance with home training
was poor
Exposure hours: control: 34,955
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*ACL = anterior cruciate ligament; BESS = balance error scoring system; SEBT = star excursion balance test.
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T-test, 100-yd shuttle run, vertical Mean increase women: 8% ttest, 13% vertical jump, 35%
jump, standing long jump, timed
wall sit, 16% push-ups
cone touch defensive slide, wall
90-min, 3 3 per week for 8 wks during
Mean increase men: 4% t-test,
sit, timed push-ups
preseason
8.5% vertical jump, 64% wall
sit, 6.5% push-ups
Dynamic warm-up, agility drills, sportsspecific plyometrics, weight
training, core training, flexibility
Significant increase hamstrings
Wilkerson (44) 19 Female collegiate players; aged Sportsmetrics ACL injury prevention Isokinetic quadriceps, hamstring
19 6 1.4 y
program
strength; forward step-down test peak torque, hamstrings/
quadriceps ratio 60°s21
and forward lunge test on force
3 3 per week for 6 wks during
plate, T-test using infrared motionpreseason entire program
analysis system
Myrick (34)
the
Injury rates via Canadian
Intercollegiate Sports Injury
Registry
Exposure hours: experimental:
39,369
Stop jump: decrease knee
flexion (valgus) moment
during stance phase
Drop jump: increase in initial
knee flexion and maximum
knee flexion angles during
stance phase
Improved vertical jump, singleleg timed hop
Journal of Strength and Conditioning Research
Core strength, single-leg passing, 3
jumps
Basketball players inseason, soccer
players preseason
920 Adolescent players; aged 12– Experimental group: general injury
reduction program
18 y; Experimental: 250 girls,
244 boys, Control: 206 girls,
5 Additional minutes in warm-up of
220 boys
balance training, and 20-min home
program with wobble board
Control group: normal warm-up
In-season, study lasted 1 y
5 Female, 5 male high school
Serious knee injury prevention
players; aged 16–18 y
program.
Testing done after 2 and 4 wks of Experimental group: no
training
difference between 2- and 4wk evaluations
Basketball Neuromuscular Training Program
reach was measured. Then, a countermovement maximum
jump with arm swing was performed 3 times and the highest
jump obtained recorded. The reliability for the assessment of
vertical jump height using the Vertec was reported by others
to be excellent, with ICCs of 0.92 (11) and 0.94 (46).
Eighteen-meter Sprint Test. Sprint speed was assessed by an
18-m sprint test. A distance of 18 m was measured on the
basketball court with the start and finish lines clearly marked
with masking tape or cones. The subjects were instructed to
sprint as fast as possible through the finish line, making sure
not to slow down before crossing the line. Each athlete
completed 1 sprint, and the time was recorded with a digital
stopwatch in one-hundredths of a second.
Neuromuscular Retraining Program. The subjects participated
in a modified Sportsmetrics Basketball (Cincinnati Sportsmedicine Research and Education Foundation) training
program. The training comprised a dynamic warm-up, jump
training, and flexibility exercises described previously (5). In
addition, strength, agility, acceleration, speed, and endurance
drills were added to specifically target the requirements of
competitive basketball players (Table 1). All the training
sessions were conducted by certified instructors; there were
3 sessions per week (on nonconsecutive days) for 6 weeks,
and all were done in the afternoon upon completion of
school. Each session lasted approximately 90–120 minutes
and was conducted at the schools’ basketball court and
weight room facilities. The instructors kept logs of all
exercises completed during each training session.
The dynamic warm-up was consistent throughout all the
sessions and included heel-toe walking, straight leg marching, leg
cradle walking, dog and bush walking, and high knee skipping
for half a court. In addition, high knees and glut kicks, stride-out
running, and all-out sprinting were done for 1 full court.
During the jump training and speed and agility drills, the
subjects were instructed and reminded to maintain a neutral
overall alignment. Verbal cues were given to keep the knees
and ankles hip distance apart and to use exaggerated knee and
hip flexion when landing from a jump, decelerating, and
cutting. Trainers gave constant feedback on jump-land
mechanics as previously described (5). Strength training
focused on hamstring, hip flexion/abduction, core, abdominal, and shoulder musculatures to aid in proper lower
extremity alignment and muscle recruitment patterns. The
subjects performed strength training in a weight room using
machines, free weights, a cable system, and body weight
exercises. At the end of each session, flexibility exercises were
performed that targeted the hamstrings, quadriceps, iliotibial
band, hip flexors, gastrocnemius/soleus, deltoid, triceps,
pectoralis major, biceps, and low back.
Statistical Analyses
For data that were normally distributed (KolmogorovSmirnov test), a 2-tailed paired t-test was used to detect
the differences between the 2 test periods. Data that failed the
716
the
normality test were assessed with Wilcoxon matched-pairs
signed-ranks tests. Chi-square analyses were used to compare
the distribution of the subjects in the percentile rank
subcategories before and after training in the MSFT and in
the 3 normalized knee separation distance categories (#60,
61–80, and .80%) in the drop-jump test. Effect sizes were
calculated and interpreted according to Cohen’s standards
(13). Power and sample size were calculated to evaluate the
effect of training on the normalized knee separation
distances. With 57 subjects in this study, it was found that
this investigation had sufficient power (.90%) to detect
significant differences in normalized knee separation distances (at least 15 6 1%) and in estimated V_ O2max values (at
least 5 6 1) at a level of 0.05. For all comparisons, a level of
p # 0.05 was considered to be statistically significant.
RESULTS
In the video drop-jump test, statistically significant increases
were found between pretrained and posttrained test sessions
on landing in the mean absolute knee separation distance
(p , 0.0001), the mean normalized knee separation distance
(p , 0.0001), and in the distribution of the subjects in the
normalized knee separation distance categories (p , 0.0001,
Table 2, Figure 2). Improvement in the normalized knee
separation distance was demonstrated in 91% of the subjects.
A statistically significant improvement was found in the
mean estimated V_ O2max score (p , 0.0001) and in the
difference in the distribution of the subjects in the categories
between pretrain and posttrain test sessions (p , 0.0001,
Figure 3). Eighty-nine percent of the subjects improved this
score.
A significant improvement was found in the vertical jump
test (p , 0.0001), as 70% of the subjects increased their scores.
However, the effect size was small (0.09). There was no
significant improvement in the 18-m sprint test. No subject
sustained an injury that resulted in loss of time training or that
required formal medical attention. All the subjects attended
at least 14 of the 18 training sessions.
DISCUSSION
This investigation measured the effects of a basketball
neuromuscular and performance enhancement training program in high school female athletes aged 14–17 years on lower
limb alignment on a video drop-jump test, estimated V_ O2max,
vertical jump height, and sprint speed. The training program
was unique in that it combined components from a published
ACL injury prevention program for jump and strength training
with other exercises and drills to improve speed, agility, overall
strength, and aerobic conditioning. The main findings of this
study were a significant increase in the mean estimated
V_ O2max and improved lower limb alignment on landing from
a drop jump. Aerobic fitness is paramount in basketball,
because players will experience fatigue as the game progresses,
which can negatively affect performance (7). Improvement in
lower limb alignment on a drop jump from a valgus position
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to a more neutral position is believed to be beneficial in
preventing noncontact ACL injuries (24,39).
The motivation for our investigation stemmed from the
desire expressed by athletes and coaches to broaden the
existing Sportsmetrics ACL prevention training program to
include speed, agility, and aerobic conditioning geared
toward basketball. In addition, other authors have speculated that improved compliance with knee injury prevention training programs would most likely occur if the
programs focused on performance enhancement and
neuromuscular retraining and we agreed with this approach
(3,27). Our study demonstrated excellent athlete participation because 18 players (31%) attended 14–15 sessions,
22 (38%) players attended 15 sessions, and 17 players (30%)
attended 17–18 sessions.
In this investigation, 88% of the athletes had #60%
normalized knee separation distance on landing from a drop
jump before training, indicating a distinct valgus lower limb
alignment. This lower limb alignment is believed to be
a potential risk factor for a future noncontact ACL injury and
the International Olympic Committee recommended use of
the drop-jump test to identify athletes at-risk for a noncontact
ACL injury (39). Stensrud et al. (41) reported that a subjective
interpretation of knee control on landing during this test
provided a useful screening tool for identifying athletes with
poor lower limb mechanics. Studies that analyzed ACL
injuries using video analysis of the actual event commonly
described a valgus knee position that was present either
milliseconds before, after, or at the time of the ligament
rupture (8,28,29). After training, only 27% of the subjects in
our study continued to show such poor knee separation
distances. One study showed that improvements in overall
lower limb alignment on the drop-jump test were retained up
to 1 year after Sportsmetrics training in a group of high
school volleyball players (6). Future studies are required in
basketball players to determine if a similar retention effect
occurs. The drop-jump video test provides a general indicator of an athletes’ lower limb axial alignment in the
coronal plane because it shows the position of the hips,
knees, and ankles in a single plane during 1 task (37). It is
important to note that many noncontact ACL injuries usually
occur in side-to-side, cutting, or multiple complex motions in
more than 1 plane.
In this study, 52% of the subjects were either in the poor
(17%) or fair (35%) MSFT categories before training.
Improvements were found in 89% of the subjects and after
training, only 14% were in the poor or fair categories. The
MSFT has been used in many investigations to determine the
cardiovascular fitness levels of children aged 6–19 years (42),
junior rugby league players (20), elite junior male basketball
players (7,16), average junior-level male basketball players
(16), and youth soccer players (45) and is recommended by
the American College of Sports Medicine (19) as a valid and
reliable method to estimate V_ O2max. We were unable to find
any other study that assessed the effects of a neuromuscular
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and performance intervention training program using MSFT
data in female high school basketball players.
Improvements were found in 70% of our subjects for the
vertical jump tests; however, the effect size was small, and the
increases ranged from 1 to 9.5 cm (mean, 2.3 cm). Chappell
and Limpisvasti (10) reported significant increases in vertical
jump height in a study consisting of 12 collegiate female
basketball players and 18 collegiate female soccer players.
The athletes participated in a 15-minute warm-up program
that included core strength, single-leg passing, and 3 jumps
before each practice during their season. Vertical jump height
increased 7%, from 45.1 6 14.1 to 48.8 6 13.9 cm (p , 0.001)
after training. These results are not comparable with those of
this study because they involved Division I collegiate athletes
and included soccer players. Athletes who do not improve
their vertical jump height may benefit from different
plyometric exercises than those used in the program in the
current investigation. De Villarreal et al. (15) summarized
data from 56 studies that assessed the effects of plyometric
training on improving vertical jump height and concluded
that a combination of squat, countermovement, and depth
jumps was significantly more effective than the use of a single
plyometric exercise (p , 0.05) (15). The overall enhancement
in vertical jump height after training was 3.90 cm or
approximately 7%. Advanced plyometric training does carry
the risk of injury or the development of an overuse syndrome.
We believe that athletes must first be taught proper jump and
landing techniques through the neuromuscular training
program described in this investigation before performing
advanced plyometrics. In addition, supervision is required to
ensure the athlete performs the exercises safely and correctly.
Six other investigations of ACL injury prevention programs
(10,26,31,33,43,44) and 2 general injury prevention programs
(17,34) designed for female basketball players have been
published to date (Table 3). These studies demonstrated
success in reducing vertical ground reaction forces during
jumping (43) and in improving isokinetic knee flexor peak
torque (44); knee flexion angle, knee separation distance, and
valgus moments on a rebound jump task (31); static and
dynamic balance (33); dynamic lower limb alignment control
during a stop jump shot (26); and knee flexion on a drop jump
(10). Two of these studies assessed the effects of the Sportsmetrics training program on neuromuscular and performance enhancement factors. Wilkerson et al. (44) conducted
this program in 11 female collegiate basketball players during
preseason conditioning sessions. After training, a significant
increase was measured in hamstrings peak torque at 60°s21
(pretrain, 90.81 6 17.91 Nm and posttrain, 98.12 6 20.91 Nm,
p = 0.008), with every subject showing improvement. Vescovi
et al. (43) implemented the plyometric jump retraining
portion of Sportsmetrics in 10 collegiate female basketball
players 3 times a week for 6 weeks during an intramural
basketball league season. Compared with a control group of
10 collegiate female players, the experimental group
demonstrated reductions in vertical ground reaction forces
VOLUME 26 | NUMBER 3 | MARCH 2012 |
717
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Basketball Neuromuscular Training Program
during a countermovement jump. Specifically, 8 of the 10
trained athletes showed a mean reduction of 478.8 6 325.0 N.
There was no difference in the absolute change in values
between groups for countermovement vertical jump height
or other associated kinetic variables. The study was limited
by the small sample size and the absence of the strength and
flexibility portions of the Sportsmetrics program.
One limitation to our study was that there was no control or
comparison group, which will be included in future studies.
We did not control for activities athletes may have been
involved in before training; however, none had participated in
a neuromuscular training program, and none were playing
organized basketball at the time the training was initiated.
Additional studies are required to determine if this program
also reduces the incidence of noncontact ACL injuries during
basketball practice and competition. In addition, it remains to
be determined if this program results in improved player
performance during competition. The program was conducted in female high school basketball players of varying
experience levels, and the results may not be applicable to elite
or collegiate players. There was no improvement in sprint
time; however, this may be because of the use of a digital
stopwatch for a short distance. Although a digital stopwatch
may be appropriate for tests of longer distances, such as the
200-m sprint as analyzed by Hetzler et al. (22), it may not be
sensitive enough to detect significant differences for the 18-m
sprint used in our study.
PRACTICAL APPLICATIONS
The findings of this study indicate the effectiveness of a new
basketball training program in female high school athletes.
The program combines components from a previously
published ACL injury prevention program for jump and
strength training with other exercises and drills to improve
speed, agility, overall strength, and aerobic conditioning. This
program may be conducted in the off-season or just before
the beginning of the high school basketball season. All
training is done on a high school basketball court and weight
room. We recommend that coaches and trainers who wish to
implement this program conduct the tests that were done in
this study to determine the overall effectiveness of the
program. Athletes who fail to improve should be encouraged
to continue neuromuscular training.
ACKNOWLEDGMENTS
The authors acknowledge Tony Rolinski, Director of
Strength and Conditioning for Olympic Sports, University
of Notre Dame for the Figure 4 drill, shoot and sprint, and
Irish ‘‘D’’ drills; and Bigger Faster Stronger, Inc. (Salt Lake
City, UT, USA) for the dot drills.
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