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A Pilot Study: Evaluations of Compression Garment Performance via Muscle Activation Tests

DOI: 10.1016/j.proeng.2013.07.059
Authors:
Ping Wang at Sun Yat-Sen University
Ping Wang
Jason McLaren at Renew
Jason McLaren
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Kah Fai Leong at Nanyang Technological University
Kah Fai Leong
Pascal Joubert des Ouches
Pascal Joubert des Ouches
Pascal Joubert des Ouches
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Abstract and Figures

Sports compression apparel consists of elastic textile that exerts pressure onto muscles. It is common for sportswear which consists of elastic textile that exerts pressure onto muscles to improve athletic performance and reduce sports injury. Since muscle activation is very sensitive to external conditions, the differences associated with muscle activations can be detected during running with or without wearing compression garments. This pilot study explored the effects of muscle activation with and without sport compression garments during running. In order to standardize the running process, the mean normalized running velocity was around 5-7 m/s. Surface electrodes were applied to the signal was synchronized with video recording and collected from subjects during treadmill running. The EMG signal was processed by a proposed method to represent the muscle activation. The muscle activation for the major muscles of Rectus Femoris (RF) and Gastrocnemius (GN) revealed a higher muscle activation is being exerted without wearing a compression garment. With limited scientific work in the field of EMG analysis and sports compression garments, further research should explore pathways which enable a better understanding of the correlations that may exist between EMG activity, garment compression and performance. (C) 2013 The Authors. Published by Elsevier Ltd.
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P r o c e d i a E n g i n e e r i n g 6 0 ( 2 0 1 3 ) 3 6 1 – 3 6 6
1877-7058 © 2013 The Authors. Published by Elsevier Ltd. Open access under CC BY-NC-ND license.
Selection and peer-review under responsibility of the School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University
doi: 10.1016/j.proeng.2013.07.059
Avai lab le on li ne at www.s cie nc edire ct .com
6th Asia-Pacific Congress on Sports Technology (APCST)
A pilot study: Evaluations of compression garment
performance via muscle activation tests
Ping Wang
a
,b,*, Jason McLarena, Kah Fai Leongb, Pascal Joubert des Ouchesa
aInstitute for Sports Research (ISR), Nanyang Technological University (NTU), Singapore 639798, Singapore
bSchool of Mechanical and Aerospace Engineering, Nanyang Technological University (NTU), Singapore 639798, Singapore
Received 20 March 2013; revised 6 May 2013; accepted 9 June 2013
Abstract
Sports compression apparel consists of elastic textile that exerts pressure onto muscles. It is common for sportswear
which consists of elastic textile that exerts pressure onto muscles to improve athletic performance and reduce sports
injury. Since muscle activation is very sensitive to external conditions, the differences associated with muscle
activations can be detected during running with or without wearing compression garments. This pilot study explored
the effects of muscle activation with and without sport compression garments during running. In order to standardize
the running process, the mean normalized running velocity was around 5-7 m/s. Surface electrodes were applied to
the signal was synchronized with video recording and collected
from subjects during treadmill running. The EMG signal was processed by a proposed method to represent the
muscle activation. The muscle activation for the major muscles of Rectus Femoris (RF) and Gastrocnemius (GN)
revealed a higher muscle activation is being exerted without wearing a compression garment. With limited scientific
work in the field of EMG analysis and sports compression garments, further research should explore pathways which
enable a better understanding of the correlations that may exist between EMG activity, garment compression and
performance.
© 2013 Published by Elsevier Ltd. Selection and peer-review under responsibility of RMIT University
Keywords: Compression garments; muscle activation; EMG
* Corresponding author. Tel.: (65) 6790 6551.
E-mail address: WangP@ntu.edu.sg.
© 2013 The Authors. Published by Elsevier Ltd. Open access under CC BY-NC-ND license.
Selection and peer-review under responsibility of the School of Aerospace, Mechanical and Manufacturing Engineering,
RMIT University
362 Ping Wang et al. / Procedia Engineering 60 ( 2013 ) 361 – 366
1. Introduction
EMG analysis is a substantial component often used for the assessment of muscle activity [1-4]. Many
researchers have evaluated the effects of sports compression apparel using EMG, applied testing methods
and mathematical modelling. However, there seems to be limited scientific work which has explored
whether wearing compression garments has an influence on muscle activation during running [5].
Designing systemic methodology for sports compression garment evaluation based on laboratory testing
is quite challenging as revealed in a review paper conducted by Liu et al (2011) [6]. It also becomes
difficult to quantify the effects different sports compression garments may have on factors such as muscle
strength, fatigue, EMG and MMG activity since muscle activation is very sensitive to external conditions
[7-8]. If the underlying regulation of a muscle pattern is identified it may lead to a better understanding of
compression garment. This paper continues from previous literature to further evaluate the effects sports
compression garments has on EMG activity during running.
2. Methods
In this pilot study, we investigated muscle activation using an EMG with and without wearing sport
compression garments during running. In order to standardize the running process, the mean normalized
running velocity was around 5-7 m/s. The EMG signal was synchronized with video recording and
collected from subjects during treadmill running. The EMG signal was processed by a proposed method
to represent the muscle activation.
The EMG data were collected at 1000Hz with a wireless Delsys EMG system. Surface electrodes were
applied to the major muscles of the skin. The location of each electrode placement was the thigh
and shank, as shown in Fig. 1.
Fig. 1. Experimental setup: (a) rectus femoris (RF) and Gastrocnemius (GN) muscle groups with EMG surface electrodes; and (b)
three experiments to quantify the compression garment with participants running on a treadmill with/without wearing compression
garments
RF
GN
Trial 1: without
garment
Trial 2: shortened pants
garment
Trial 3: pants garment
363
Ping Wang et al. / Procedia Engineering 60 ( 2013 ) 361 – 366
While collecting EMG, the participants ran on constant speed on a treadmill. The subjects commenced
walking prior and following the run trial to account for the accelerations and decelerations during
running.
1. Running trials were carried out at same speed per participant including without wearing garment,
with wearing shortened pants and wearing pants garments. EMG signal was recorded down for
comparisons. Every trial lasted 20 second and repeated three times.
2. Major muscle activations were represented by the processed EMG signals through all entire
recording.
3. The average muscle activation volumes per running cycle were calculated to highlight the effect
of the compression garment.
3. Results
The representative muscle activation for the major muscle Gastrocnemius (GN) of one participant is
shown in Fig. 2. The results of three trials were compared and a decrease in muscle activity was revealed
throughout the entire 20 second recording. As shown in figure 2, the raw data collected from the
participant without wearing a compression garment presents a larger muscle activation volume than when
wearing a compression garment. The frequency of activation and inactivation are similar and therefore,
the effect of a compression garment focuses on a reduced muscle activation. The other effect is not
obvious and the different between different types of garments, then performances of the two garments are
therefore similar as shown in this study.
Fig. 2. EMG comparisons between muscle activation of participant without wearing compression garment, wearing shortened pants
compression garment and long pants compression garment.
364 Ping Wang et al. / Procedia Engineering 60 ( 2013 ) 361 – 366
Table 1. Comparison between different participants
Participant
Garment Size
Leg length (cm)
Speed (m/s)
Muscle
Trials
EMG
1
48
87
5.4
GN
w/o
28.56
Short
12.85
long
18.34
RF
w/o
5.97
Short
1.54
long
1.08
2
50
89
5.5
GN
w/o
99.63
Short
48.78
long
63.86
RF
w/o
91.93
Short
40.86
long
42.36
3
46
86
5.5
GN
w/o
80.67
Short
41.16
long
42.75
RF
w/o
93.19
Short
30.29
long
29.76
4
44
85
5.5
GN
w/o
19.77
Short
23.21
long
10.7
RF
w/o
17.09
Short
10.63
long
5.98
5
46
87
5.5
GN
w/o
16.18
Short
13.65
long
5.04
RF
w/o
17.25
Short
16.34
long
16.03
In order to investigate the change of muscle activity, root mean square (RMS) is processed and
compared for the overall tendency as shown in Fig. 3. There tends to be a significant decrease in muscle
activity presented in the major muscles during running at same speed. More of this effect is shown on the
rectus femoris (RF) than Gastrocnemius (GN). The difference between the two types of garments is
similar. Each result per participant is listed in Table 1 and the average results of the five participants are
also presented.
365
Ping Wang et al. / Procedia Engineering 60 ( 2013 ) 361 – 366
Fig. 3. Processed EMG signal to represent muscle activation to evaluate the effect of compression garment on major muscle groups
of the lower limb. Trial 1 is carried out on participant without wearing compression garment; Trail 2 is carried out on participant
with wearing short pants compression garment; and Trail 3 is carried out on participant with wearing long pants compression
garment.
4. Conclusions
The major muscles of the Rectus Femoris and Gastrocnemius contributing to running needed to exert
more muscle power without wearing the compression garment. Unnecessary muscle activation can
accelerate the onset of fatigue and increase the risk for sport injury. During running it may be more
advantageous to wear the compression garments where less muscle activation is occurring. Researchers
stability on muscle vibrations [8] while compression garment may prevent muscle vibrations during
sports activities which may enhance athletic performance.
Furthermore, muscle activation can be of interest to sports compression garment manufacturers who
seek to enhance sports performance through gradient compression garment design. Hence, it is necessary
to determine if a link exists between muscle activity and the performance of sports compression garments
during dynamic activities. Such an evaluation study would assist with the efficacy of gradient
compression garment development.
Acknowledgements
The kind consent of five volunteer subjects to participate the running trial is greatly appreciated. The
financial support by ISR is also acknowledged.
References
[1] P. Wang, K. H. Low, and A. H. McGregor, "A subject-based motion generation model with adjustable walking pattern for a
gait robotic trainer: NaTUre-gaits," in 2011 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), San
Francisco, CA, 2011.
[2] P. Wang, K. H. Low, A. H. McGregor, and A. Tow, "Detection of abnormal muscle activations during walking following
spinal cord injury (SCI)," Research in Developmental Disabilities, vol. in press, 2013.
366 Ping Wang et al. / Procedia Engineering 60 ( 2013 ) 361 – 366
[3] P. Wang, K. H. Low, A. Tow, and P. H. Lim, "Initial system evaluation of an overground rehabilitation gait training robot
(NaTUre-gaits)," Advanced Robotics, vol. 25, pp. 1927-1948, 2011.
[4] P. Wang, A. McGregor, A. Tow, H. B. Lim, L. S. Khang, and K. H. Low, "Reha bilitation control strategies for a gai t robot
via EMG evaluation," in IEEE 11th International Conference on Rehabilitation Robotics (ICORR), Kyoto, Japan, 2009, pp. 86-91.
[5] A. Coza and B. M. Nigg, "Compression apparel effects on soft tissue vibrations," University Michigan, Ann Arbor, USA,
2008.
[6] Y. Liu, W. J. Fu, J. L. He, and X. J. Xiong, "Research advancements of compression equipments in sports science," in
International conference on future computer science and education (ICFCSE), 2011, pp. 110-113.
[7] Y. Liu, W. J. Fu, and X. J. Xiong, "The effect of different external elastic compression on muscle strength, fatigue, EMG and
MMG activity," presented at the Proceedings of the 27th international conference on biomechanics in sports, Limerick, Ireland,
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[8] N. Miyamoto, K. Hirata, N. Mitsukawa, T. Yanai, and Y. Kawakami, "Effect of pressure intensity of graduated elastic
compression stocking on muscle fatigue following calf-raise exercise," Journal of Electromyography and Kinesiology, vol. 21, pp.
249-254, Apr 2011.
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Article
  • Apr 2011
The purpose of the present study was to examine the effects of wearing a graduated elastic compression (EC) stocking, with different pressure profiles during a fatiguing calf-raise exercise session, on the torque generating capacity after exercise. Fourteen subjects performed 15 sets of 10 repetitions of calf-raise exercise, wearing one of three stockings of different compression pressure profiles: two kinds of EC stockings (one (EC30) with 30mmHg at the ankle, 21-25mmHg at the calf, and 10mmHg below the knee, and the other (EC18) with 18, 12-14, and 7mmHg at the same regions, respectively) and a non-EC sport stocking as a control (CON). Before and after the exercise, torque and electromyographic (EMG) signals of medial gastrocnemius and soleus muscles were recorded during an evoked triplet contraction and the maximal voluntary contraction (MVC). All stockings had no effect on the decline of the MVC torque whereas the reduction of the evoke triplet torque in EC30 stocking condition was significantly smaller compared with that in CON (-6.4±8.5% for EC30 and -16.5±9.0% for CON, P<0.05). The reduction of the mean power frequency of EMG during MVC in the EC30 condition was significantly smaller than that in CON (-4.4±10.9Hz for EC30 and -18.7±7.9Hz for CON, P<0.05). These results suggest that the EC stocking with adequate pressure at the calf region relieves muscle fatigue of the triceps surae induced by calf-raise exercise.
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The effect of different external elastic compression on muscle strength, fatigue, EMG and MMG activity
  • Jan 2009
  • Y Liu
  • W J Fu
  • X J Xiong
Y. Liu, W. J. Fu, and X. J. Xiong, "The effect of different external elastic compression on muscle strength, fatigue, EMG and MMG activity," presented at the Proceedings of the 27th international conference on biomechanics in sports, Limerick, Ireland, 2009.
“The effect of different external elastic compression on muscle strength, fatigue, EMG and MMG activity”
  • Jan 2009
  • Liu