1. References
1. HUNTER, J.P., R.N. MARSHALL, AND P.J. MCNAIR. Relationships between ground reaction force impulse and kinematics of sprint-running acceleration. Journal of applied biomechanics. 21(1):31-43. 2005.
2. LOCKIE, R.G., S.J. CALLAGHAN, T.S. MCGANN, AND M.D. JEFFRIESS. Ankle muscle function during preferred and non-preferred 45° directional cutting in semi-professional basketball players. Int J Perform Anal
Sport. 14(2):574-593. 2014.
3. NEPTUNE, R.R., I.C. WRIGHT, AND A.J. VAN DEN BOGERT. Muscle coordination and function during cutting movements. Med Sci Sports Exerc. 31(2):294-302. 1999.
4. SCANLAN, A., B. DASCOMBE, and P. REABURN. A comparison of the activity demands of elite and sub-elite Australian men's basketball competition. J Sports Sci. 29(11):1153-1160. 2011.
ANKLE MUSCLE FUNCTION IN FASTER AND SLOWER BASKETBALLERS DURING A
REACTIVE CUT
Dr. Robert Lockie1, Adrian Schultz2, Tye McGann2, Farzad Jalilvand1, Samuel Callaghan3, and Matthew Jeffriess4.
1Department of Kinesiology, California State University, Northridge, Northridge, USA.
2Exercise and Sport Science, University of Newcastle, Ourimbah Campus, Australia.
3School of Exercise and Health Sciences, Edith Cowan University, Australia.
4Sport and Exercise Discipline Group, University of Technology Sydney, Australia.
Introduction
Basketball requires frequent direction changes and cutting during match-play, often under reactive conditions.4
The ankle joint assists with force production and absorption during stance,1 while the surrounding muscles (tibialis anterior [TA],
peroneus longus [PL], peroneus brevis [PB], soleus [SOL]) facilitate dynamic joint movement and stabilization;3 however, there has been
relatively little scientific analysis of the ankle has with regards to cutting and performance.2,3
The purpose of this study was to determine whether peak activation of the TA, PL, PB, and SOL differentiated between faster and slower
basketball players in a reactive cutting task.
Practical Applications
Although important, ankle nEMG generally did not
discriminate between faster and slower cutting.
Strength and conditioning coaches should incorporate
exercises that develop PL strength, as this may assist with
ankle motion during reactive cutting. This could include
using exercises such as hop-and-holds, jump landings, and
unilateral squats on unstable surfaces.
Preferred Non-Preferred
Muscle Faster Slower p value d Faster Slower p value d
Outside Cut Leg
TA 73.99 ± 38.72 91.49 ± 30.59 0.303 0.50 90.17 ± 22.04 82.07 ± 23.87 0.465 0.35
PL 84.13 ± 28.67 85.66 ± 43.89 0.931 0.04 89.35 ± 31.43 69.40 ± 24.84 0.155 0.70
PB 99.75 ± 33.60 97.41 ± 23.87 0.867 0.08 98.08 ± 56.08 98.56 ± 41.80 0.984 0.01
SOL 78.13 ± 30.64 99.15 ± 42.34 0.245 0.57 101.56 ± 39.20 101.56 ± 44.87 1.000 0.00
Inside Cut Leg
TA 89.51 ± 20.11 76.34 ± 22.88 0.213 0.61 85.58 ± 39.12 84.42 ± 35.63 0.949 0.03
PL 114.65 ± 42.61 62.49 ± 23.30 0.005* 1.52 109.95 ± 48.85 84.37 ± 40.88 0.246 0.57
PB 87.05 ± 43.38 90.47 ± 39.39 0.863 0.08 95.78 ± 48.95 95.30 ± 17.57 0.978 0.01
SOL 99.29 ± 40.46 87.06 ± 49.81 0.576 0.27 68.95 ± 24.89 93.40 ± 36.21 0.114 0.79
Methods
18 male basketball players (age = 22.50 ± 4.12 years; height = 1.84 ± 0.09 m; body mass = 85.11 ± 11.84 kg) with no ankle pathologies
completed six reactive randomized trials (three left and three right) of the Y-shaped agility test (Figure 1).
Electromyography (EMG) measured activity of the TA, PL, PB, and SOL for both the and inside cut legs during the change-of-direction
step (first step past the trigger gate that initiated the cut). EMG data was normalized against 10-meter sprint muscle activity (nEMG).
Preferred cut direction time was used to dichotomize the sample into faster (n = 9) and slower (n = 9) groups.
A one-way analysis of variance (p < 0.05) and effect sizes (Cohen’s d) analyzed between-group differences in cut times and ankle
muscle nEMG. Data was pooled for a correlation analysis (p < 0.05) between times and nEMG.
Acknowledgements
This study received financial assistance from the New South
Wales Sporting Injuries Committee. Thanks to Central Coast
Crusaders basketball for assisting with this research.
Results
The faster group was quicker in both the preferred and non-preferred directions (p < 0.01).
For the preferred cut, there were no between-group differences in outside leg ankle nEMG
(Table 1). For the inside leg, the faster group had an 83% greater PL nEMG when
compared to the slower group.
There were no other differences in inside leg ankle nEMG, and no differences in ankle
nEMG for either leg for the non-preferred cut. There were also no significant correlations
between Y-shaped agility test times and nEMG (Table 2).
Table 1: nEMG (%) for faster (n = 9) and slower (n = 9) basketball players from the TA,
PL, PB, and SOL, for the outside and inside legs during a change-of-direction step in the
preferred and non-preferred directions a reactive cut in the Y-shaped agility test.
Table 2: Correlations between
reactive Y-shaped agility test time in
the preferred and non-preferred
directions, with outside and inside
cut leg nEMG for the TA, PL, PB,
and SOL.
* Significant (p < 0.05) difference between the faster and slower groups.
Outside Leg Inside Leg
Preferred
TA
r
p
0.157
0.533
-0.199
0.428
PL
r
p
0.005
0.985
-0.401
0.099
PB
r
p
0.006
0.980
0.021
0.935
SOL
r
p
0.376
0.124
-0.106
0.675
Non-Preferred
TA
r
p
-0.171
0.497
-0.191
0.448
PL
r
p
-0.255
0.307
-0.257
0.303
PB
r
p
-0.065
0.799
-0.210
0.402
SOL
r
p
-0.271
0.277
0.160
0.526
Conclusions
The greater nEMG for the inside leg PL for the faster
group could have facilitated a more effective cut, as PL
has an important role in stabilizing the subtalar joint
during a cut, as well as contributing to propulsion.3
However, there no other between-group differences in
ankle nEMG, which suggest that ankle muscle activity is
generally not a differentiating factor in reactive cutting in
basketball players.
Nonetheless, given the importance of ankle muscle
function during cutting,2,3 strength and conditioning
coaches should continue to prescribe exercises that
develop all the muscles about the ankle, in the ranges of
motion experienced during cutting.
Figure 1: The Y-shaped agility test. Participants ran 5
meters (m) through the start gate to pass the trigger gate,
and cut left or right depending on which gate was
illuminated.