ChapterPDF Available

Electrical Muscle Stimulation and Its Use for Sports Training Programs: A review

Authors:
  • Erzincan Binali Yıldırım University
Chapter

Electrical Muscle Stimulation and Its Use for Sports Training Programs: A review

Abstract

EMS involves the transmission of electrical impulses via surface electrodes to peripherally stimulate motor neurons eliciting muscular contractions. EMS that has been started to be used in sports in 1960’s with Kots’ practices now became complementary, or even the alternative of the current sports training programs. This review examined the evidence available as to the efficacy of EMS in enhancing performance in athletes. EMS have largely been investigated with regard to its ability to exchange the muscular performance following EMS exercise. Furthermore, experimental models examined and discussed to reflect the circumstances of athletes are needed to further investigate the efficacy of various EMS modalities. Other potentially important factors associated with EMS, such as the stimulation parameter and their role in the muscle performance, also need to be considered in this future assessment. Key words electromyostimulation, sport training
Recent Advances in Health Sciences
Editors
A. Adil Çamlı
Bilal Ak
Ramiz Arabacı
Recep Efe
ISBN 978-954-07-4136-9
ST. KLIMENT OHRIDSKI UNIVERSITY PRESS
SOFIA 2016
ii
Editors
Assist. Prof. Dr. Ahmet Adil Çamlı
Bezmiâlem University
Faculty of Medicine
Medical Sciences Division
Fatih, Istanbul, Turkey
Prof. Dr. Ramiz Arabacı
Uludag University
Faculty of Sports Sciences
Pysical Education and Sport Dept.
Bursa, Turkey
Assist. Prof. Dr. Bilal Ak
Toros University
School of Health Sciences
Health Management Division
Yenişehir, Mersin, Turkey
Prof. Dr. Recep EFE
Balikesir University, Faculty of Arts
and Sciences
Department of Geography
Balikesir, Turkey
St. Kliment Ohridski University Press
ISBN 978-954-07-4136-9
The contents of chapters/papers are the sole responsibility of the authors, and
publication shall not imply the concurrence of the Editors or Publisher.
© 2016 Recep Efe
All rights reserved. No part of this book may be reproduced, in any form or by any
means, electronic, mechanical, photocopying, recording or otherwise, without prior
permission of the editors and authors
Cover Design: Murat Poyraz
iii
CONTENTS
Chapter 1 ........................................................................................................................ 1
Nursing Services in the Ottoman Empire
Behire SANÇAR
Chapter 2 ...................................................................................................................... 14
Posttraumatic Stress Disorder Among Veterans and Well-Being: What Can
Nurses Do about It?
Derya ADIBELLI
Chapter 3 ...................................................................................................................... 26
What Is Nursing Informatics?
Hava GÖKDERE ÇINAR, Semra SÜRENLER, Nurcan ÖZYAZICIOĞLU
Chapter 4 ...................................................................................................................... 32
Transactional Analysis Approach in Patient-Nurse Communication
Zümra ÜLKER DÖRTTEPE, İlkay KESER
Chapter 5 ...................................................................................................................... 43
The Pain Management in Intensive Care Units
Dilek YILMAZ, Yurdanur DİKMEN, Dilek KARAMAN
Chapter 6 ...................................................................................................................... 54
Responsibilities of Nurses in Use of Complementary and Alternative Medicine in
Cancer Patients: Importance of Reflexology and Progressive Muscle Relaxation
Exercises
Hacer ALAN DİKMEN, Füsun TERZIOĞLU
Chapter 7 ...................................................................................................................... 69
Patient Satisfaction and Quality of Care in Pediatric Settings
Bedriye AK
Chapter 8 ...................................................................................................................... 77
Preoperative Anxiety and Postoperative Pain for Tonsillectomy in Adult Patients:
The Effect of Education and Follow-Up Telephone Calls
Rahşan ÇEVİK AKYIL, Nadiye ÖZER, Özgür YÖRÜK
Chapter 9 ...................................................................................................................... 87
The Disease of Our Time: Vitamin D Deficiency and Hypovitaminosis D
Elif ÜNSAL AVDAL, Yasemin TOKEM, Berna Nilgün ÖZGÜRSOY URAN
Chapter 10 .................................................................................................................... 94
Abuse in Old Age and Nursery Approach
Çiğdem KAYA, Perihan SOLMAZ, Ebru KURDAL BAŞKAYA
Chapter 11 .................................................................................................................. 104
Strategies and Models for Evidence Based Nursing Practice
Yasemin YILDIRIM USTA, Songül ÇAĞLAR
Chapter 12 .................................................................................................................. 113
Use of Technology in Nursing Education
İlknur BEKTAŞ, Figen YARDIMCI
iv
Chapter 13 .................................................................................................................. 119
The Cost of Nursing Compassion Fatigue: A Literature Review .......................................
Yurdanur DİKMEN, Nasibe Yağmur FİLİZ, Handenur BAŞARAN
Chapter 14 .................................................................................................................. 137
Drug Errors and Nurses' Responsibilities for Their Prevention
Aylin PALLOŞ
Chapter 15 .................................................................................................................. 148
Physiology of Nervous System
Derya Deniz KANAN
Chapter 16 .................................................................................................................. 164
Pediatric Patient Safety
Figen YARDIMCI, İlknur BEKTAŞ
Chapter 17 .................................................................................................................. 174
Ergonomics in Delivery Rooms and its Importance
Nevin ÇITAK BİLGİN
Chapter 18 .................................................................................................................. 183
Pregnancy and Healthy Life Style Behaviours
Sezer ER GÜNERİ
Chapter 19 .................................................................................................................. 200
The Use of Simulation in the Improvement of the Clinical Skill and Competency
of the Nursing Students
Yurdanur DİKMEN, Fatma TANRIKULU, Funda EROL
Chapter 20 .................................................................................................................. 217
The Effects of Gestational Diabetes on Postpartum Period
Gülşen IŞIK, Nuray EGELİOĞLU CETİŞLİ
Chapter 21 ................................................................................................................. 237
Results of Maternal Obesity
Nuray EGELIOGLU CETISLI
Chapter 22 .................................................................................................................. 243
Parents Attachment and Nursing Approach
Selma ŞEN
Chapter 23 .................................................................................................................. 249
Complementary and Alternative Medicine (CAM) in the Treatment of Infertility
Yasemin AYDIN, Merve KADIOĞLU
Chapter 24 .................................................................................................................. 263
Elderly Home Care Services
Nazife AKAN
Chapter 25 .................................................................................................................. 281
Non-pharmacological Methods Administered in Painful Interventional
Procedures on Children
Fatma YILMAZ KURT, Aynur AYTEKİN, Sibel KÜÇÜKOĞLU
v
Chapter 26 .................................................................................................................. 299
Nutrition Literacy in the Prevention of the Era’s Growing Problem Obesity
Büşra CESUR
Chapter 27 .................................................................................................................. 307
Adolescent Pregnancy and Nursing Approach
Selma ŞEN
Chapter 28 .................................................................................................................. 315
Complementary and Alternative Medicine Use in Pregnancy
Emine KOÇ, Şükran BAŞGÖL
Chapter 29 .................................................................................................................. 327
The Importance of Food Labels in Nutritional Literacy
Büşra CESUR
Chapter 30 .................................................................................................................. 332
The Importance of Breastfeeding Professional Consultation, Peer Education
and Support
Zeliha Burcu YURTSAL
Chapter 31 .................................................................................................................. 338
Nursing/Midwifery Approaches to Fear of Childbirth
Dilek COŞKUNER POTUR
Chapter 32 .................................................................................................................. 350
Sexual Dysfunction in Women and Nursing Approach
Şükran BAŞGÖL, Emine KOÇ
Chapter 33 .................................................................................................................. 361
Using the Model to Assess Sexual Health
Funda EVCİLİ
Chapter 34 .................................................................................................................. 367
The Importance of Human Milk and Breastfeeding in Terms of Community
Health
Zeliha Burcu YURTSAL
Chapter 35 .................................................................................................................. 373
The Use of Reflexology in Women's Health Reflexology
Nursen BOLSOY
Chapter 36 .................................................................................................................. 386
Peer Education and Sexual Health
Funda EVCILI
Chapter 37 .................................................................................................................. 393
Children with Specific Learning Disability
Hülya TERCAN, Müdriye YILDIZ BIÇAKCI
Chapter 38 .................................................................................................................. 405
The Study of Social Skills and Peer Attachment of Adolescent
Asya ÇETİN, Arzu ÖZYÜREK
vi
Chapter 39 .................................................................................................................. 409
Supporting Memory Development in Early Childhood
Arzu ÖZYÜREK, Asya ÇETİN
Chapter 40 .................................................................................................................. 414
Role of Child Development Specialist in Early Intervention Process
Çiğdem AYTEKIN
Chapter 41 .................................................................................................................. 427
The Situation of the Children's Home in Turkey
Figen GÜRSOY, Fatih AYDOĞDU
Chapter 42 .................................................................................................................. 437
Normal Developing Siblings of Children Having Different Problems
Selvinaz SAÇAN
Chapter 43 .................................................................................................................. 452
Investigation of the Development of Premature and Non-Premature Children
Didem EMRE BOLATBAŞ, Müdriye YILDIZ BIÇAKÇI
Chapter 44 .................................................................................................................. 459
Epidemiology of Urinary Incontinence and Risk Factors
Ayten DİNÇ
Chapter 45 .................................................................................................................. 472
Approach to Inflammatory Bowel Diseases with Current Guidelines
Berna Nilgün ÖZGÜRSOY URAN, Elif ÜNSAL AVDAL, Yasemin TOKEM
Chapter 46 .................................................................................................................. 488
Balneotherapy and Health
Bülent ÖZDEMIR, Levent ÖZDEMİR
Chapter 47 .................................................................................................................. 494
Color Stability of Provisional Materials Used in Dentistry
Ayşe Nurcan DUMAN
Chapter 48 .................................................................................................................. 508
Enteral Nutrition
Hülya KAMARLI, Aylin AÇIKGÖZ
Chapter 49 .................................................................................................................. 524
The New Favorite of Children and the Young: Energy Drinks
Selvinaz SAÇAN, Hakan Murat KORKMAZ
Chapter 50 .................................................................................................................. 532
Energy Drinks: Contents, Effects and Awareness of Consumption
Fatma ÇELİK KAYAPINAR, İlknur ÖZDEMİR
Chapter 51 .................................................................................................................. 547
Some Wild Plants Commonly Used in Folk Medicine in Turkey
Sefa AKBULUT, Mustafa KARAKÖSE
vii
Chapter 52 .................................................................................................................. 560
Mobbing; Effects on the Mental Health and Protection
Nermin GÜRHAN, Ebru KURDAL BAŞKAYA and Perihan SOLMAZ
Chapter 53 .................................................................................................................. 572
Smoking Behaviour Among High School Teachers in Turkey
Ayten DİNÇ
Chapter 54 .................................................................................................................. 580
The Effect of Developing Technology on the Family Structure and Family
Relations
Derya ADIBELLI, Rüveyda YÜKSEL
Chapter 55 .................................................................................................................. 590
The Rules of Requirement in the Swimming Pools
Cemal GÜNDOĞDU, Evrim ÇELEBİ
Chapter 56 .................................................................................................................. 600
Gender Perspective on Leadership
Aslı ER KORUCU, Füsun TERZİOĞLU
Chapter 57 .................................................................................................................. 614
Legislation and Mobbing in Turkey
Nermin GÜRHAN, Ebru KURDAL BAŞKAYA, Çiğdem KAYA
Chapter 58 .................................................................................................................. 623
Hospital Management and Organization in the Ottoman Empire
Bilal AK
Chapter 59 .................................................................................................................. 640
Network Analysis; Accessibility to Hospitals with Remote Sensing and
Geographic Information Systems Techniques: A Case Study of Konyaaltı,
Antalya-Turkey
Mesut ÇOŞLU, Serdar SELİM, Namık Kemal SÖNMEZ, Dilek KOÇ-SAN
Chapter 60 .................................................................................................................. 648
The Organization of the Health Care Services in Turkey
Sabahattin TEKİNGÜNDÜZ
Chapter 61 .................................................................................................................. 670
The Role of Teamwork in Patient Safety at Healthcare Institutions
Şerife Didem KAYA, Aydan YÜCELER
Chapter 62 .................................................................................................................. 690
Theories of Play in the Context of Leisure
Ali TEKİN, Gülcan TEKİN, Emrah AYKORA
Chapter 63 .................................................................................................................. 704
Determining Some Physical and Physiological Parameters of Undergraduate
Students
Fatma ÇELİK KAYAPINAR, İlknur ÖZDEMİR
viii
Chapter 64 .................................................................................................................. 711
Electrical Muscle Stimulation and Its Use for Sports Training Programs: A
review
Fatih KAYA, Mustafa Said ERZEYBEK
Chapter 65 .................................................................................................................. 734
Prohibited Substance Use in Sports and Therapeutic Use Exemptions
Halil TANIR
Chapter 66 .................................................................................................................. 745
Exercise is Medicine
Gözde ERSÖZ
Chapter 67 .................................................................................................................. 759
Muscular Endurance Training with Electromyostimulation: Is It Possible Torque
Production in Fatigue?
Fatih KAYA, Salih PINAR, Elif Sibel ATIŞ, Andrew P. LAVENDER, Mustafa
Said ERZEYBEK
Chapter 64
Electrical Muscle Stimulation and Its Use for Sports Training
Programs: A review
Fatih KAYA, Mustafa Said ERZEYBEK
INTRODUCTION
Currently, there are several sport training methods that are used to increase the
sportive performance. However, since the target is to obtain the effects promptly, there
is a need for new and innovative methods. One of these methods is the artificial
electrical muscle stimulations (EMS) which is used as the protective strength training
(Pichon et al., 1995; Maffiuletti et al., 2000; Maffiuletti et al., 2002; Brocherie et al.,
2005; Babault et al., 2007). The general purpose of the electrical stimulations is to
develop the basic muscle properties that are related with the training (intramuscular
blood flow, maximum strength, endurance) with the help of repetitive contractions
(Pichon et al., 1995; Maffiuletti et al., 2000).
At the beginning of the several unprompted sports activities, the central nervous
system (CNS) generally activates the smallest alpha motoneurons firstly. When
exercising continues and more energy is needed to be generated for the muscles, larger
alpha motoneurons are increasingly activated (Porcari et al., 2002). It has been reported
that the electrical muscle stimulations activate the fast twitch (FT) fibers that are
generally more difficult to activate and of which the stimulation depends on the largest
alpha neurons by reversing the motor unit recruitment order (Sinacore et al., 1990); that
it enables more motor unit to take part in the training (Gregory and Bickel, 2005); that
the indirect electrical stimulation activates almost all fibers in the given muscle group
(Egginton and Hudlicka, 2000) and thus, this selective increase of the FT fibers may
improve the overall strength of a muscle or a group of muscles through the electrical
stimulation (Anderson, 2009). Electrical muscle stimulation may be an easy way to
‘train’ fast twitch motor units without great overall muscular effort (Komi, 2003).
Currently, strengthening the muscle through the electrical stimulation is a routin
procedure in the rehabilitation clinics and the studies regarding the EMS use on the
healthy skeletal muscle as a training method have been increased in the last decade.
The studies about the effects of the electrical muscle stimulations on the muscle
performance have revealed the the high frequence impulses are efficient in terms of the
strengthening (Alon and Smith, 2005; Filipovic et al., 2011; Hortobágyi 1996; Komi
2003; Matsunaga et al., 1999; Mohr et al., 1985) and the low frequence impulses are
efficient in terms of the endurance (Thériault et al., 1996; Callaghan 2002; Hamada et
al., 2004, Atherton et al., 2005). Also, the low frequence impulses are used for muscular
recovery after the fatigue (Raymond et al., 2007; Maffiuletti et al., 2011; Babault 2011).
Asst. Prof. Dr., Erzincan University, Education Faculty, Department of Physical Education
and Sport, Erzincan, Turkey
Asst. Prof. Dr., Dumlupınar University, School of Physical Education and Sport, Kütahya,
Turkey
712
The extensive variation of the stimulation parameters as well as the duration of the
entire program and of each session affect the success of the training programs.
In this research, the efficiency of EMS used in the sports training programs have
been studied and discussed and suggestions have been provided for the future
researches.
1. ELECTRICAL MUSCLE STIMULATION
The use of EMS in sports has been started in 1960’s with Kots’ practices and it has
been claimed that a new stimulation form (Russian form) strenghtens the muscles up to
40% for elite athletes (Ward and Shkuratova, 2002), and thus the use of EMS in sports
became popular. In 1970’s, these studies were shared with the Western sports
institutions. However, since the mechanisms involved in the EMS were not properly
understood, the results were conflicting. The recent medical physiological researches
have revealed precisely the adaptations of the muscle cell, blood vessels (Perez et al.,
2002; Harris, 2005) and nervous system (Hortobágyi, 1996; Boerio et al., 2005; Gondin
et al., 2006; Jubeau et al., 2006) caused the electrical stimulation.
1.1. Electrical Muscle Stimulation Mechanism
The muscular contraction resulting from the EMS is different from the voluntary
muscular contraction started by the CNS. The motor neuron excitation (action potential)
started by the nervous system or by an electrical stimulus are always exactly the same
(all or none principle) and each excitation causes the same basic mechanical muscular
response. Thus, regardless if it is started by the nervous system or EMS, the action is
similar. In this regard, the voluntary muscular action is started by the nervous system:
brain → spinal cord → motor nerve → muscle (Johnston, 2004). EMS causes an
artificial muscular activation by eliminating this process (Trimble and Enoka, 1991).
Whereas the brain is capable to stimulate most of the muscular fibers, an EMS
device can stimulate the muscular fibers up to 100%. Furthermore, unlike the human
brain, an EMS device can provide high quality impulses to make the muscles work
without causing cardiovascular and psychological fatigue. Compared to the voluntary
training alone, this enables better and safer muscle performance results. The electrical
stimulus is transferred from the EMS device to the muscles via nerve fibers or
motoneurons. The role of the impulse is to provide a muscular response (twitch) upon
conversion of the nerve stimulus into a mechanical activity. If the electrical impulse
continues, the muscle excitation/stimulation occurs and muscular twitch is repeated. If
the muscles are stimulated with the frequent impulses, the muscular fibers reach the
contraction point. Thus, the muscles respond with a constant contraction (tetanization)
and it depends on the summation of the basic responses. When the frequency of the
stimulation impulses are increased, each individual twitch becomes less significant;
until the contraction point, the appearance of the muscular contraction becomes smooth
(Johnston, 2004; Starkey, 2013).
The electrical impulse triggering the motor neuron excitation, the impulse
frequency (number of impulses per second-Hertz), contraction duration (duration of the
continous muscular contraction), rest duration (duration of the rest between the
contractions), number of repetitions (repeating contraction-rest cycle) and the intensity
(miliampere, mA) are the parameters that define the quantity and quality of the
muscular activity (Johnston, 2004; Starkey, 2013).
The number of the muscular fibers that will be recruited in the muscular activity
713
depends on the intensity of the electrical stimulus. If the stimulation comprises the
intense impulse levels, more muscular fibers would be recruited to the activty. On the
contrary, the lower density would cause a few number of fibers to take part in the
activity (Starkey, 2013).
These impulses are transferred from the EMS device to the skin through
electrodes. The electrodes transmit the electrical current to the skin and motor nerve.
When the electrodes are fixed on the skin and the current in the unit is turned on, the
stimulation is transmitted to the muscle and thus, indirectly to the motor nerve. The
appropriate electrode size and location (Forrester and Petrofsky, 2004) as well as the
quality of the current are considered and the electrical current flows between the
electrodes through the tissues (Johnston, 2004).
1.2. Electrical Muscle Stimulation Theory
The muscular performance increasing ability of the EMS protocols with regard to
both healthy and dysfunctional muscles is widely accepted and reported as a routin
together with the clinical applications (Dudley et al., 1999; Belanger et al., 2000;
Stevenson and Dudley, 2001; Lewek et al., 2001). However, although several
researchers have reported increases in the muscular performance with EMS, there are
differences in the literature with regard to the specific EMS responses compared to the
voluntary contractions. The positive effects of the EMS training have been based on
various mechanisms; especially the one about the voluntary muscle activation is related
with the recruitment order (Kubiak, Whitman, and Johnston 1987).
Henneman’s size principle (1965) defines the voluntary motor unit recruitment as
the gradual recruitment of the large, typically fast motor units after recruitment of the
small and typically slow motor units. There are certain facts that demonstrate the
variability of the size principle (Denier et al., 1985; Nardone et al., 1989) and it has
been reported that the electrical muscle stimulus is one of the factors that reverse the
motor unit recruitment order (Anderson 2009, Feiereisen et al., 1997; Porcari et al.,
2002; Komi, 2003; Starkey, 2013).
The first of the theories claims that the EMS produces intense muscle contractions
which are similar to those contractions occuring during the strength training and thus,
the muscular response emanates in a similar way to the adaptations in a regular training.
Another theory, the strongest claim is that the EMS reverses the voluntary motor unit
recruitment order (Gregory and Bickel, 2005). Despite a statement reporting that rather
than the reverse physiological voluntary recruitment order, the muscle fiber recruitment
during the EMS is of the non-selective, spatially fixed and temporarily synchronised
model (Gregory and Bickel, 2005; Maffiuletti et al., 2011), the EMS results support that
the size principles is reversed. Compared to the voluntary contractions (6%), the reverse
recruitment rate during the electrical stimulation is 28-35 % arasındadır (Feiereisen et
al., 1997) and the claim that the fast motor units are ahead of the slow motor units is
based on the two prevailing views: (1) the electrical resistence of the large axon motor
units against the external current is much lower and they transmit their action potentials
faster than the small axon motor units; (2) the data showing the increase in fatigue with
EMS, compared to the voluntary contractions (Gregory and Bickel, 2005).
The fact that EMS (75Hz) produces more cardiorespiratory demands compared to
the voluntary contractions of the same intensity and causes more muscular fatigue in a
single session, has been accepted as an indicator of the variability regarding the motor
714
unit recruitment model (Theurel et al., 2007). Another important indicator is the
glycogen discharge in the FT muscle fibers, right after the electrical stimulation
(Sinacore et al., 1990). It has been shown that the glucose carrying activity is higher in
FT’s compared to the slow twitch (ST) fibers, when EMS is applied (Roy et al., 1997).
Contrary to the motor unit recruitment order encountered during the low intensity
voluntary exercising where the ST fibers are first used (Gollnick et al., 1974), the fact
that large and fatigable glycolytic fiber FT motor units are first activated during EMS
(Sinacore et al., 1990) supports the “reverse-size principle” regarding the motor unit
recruitment with EMS. The reverse motor unit recruitment order obtained with EMS
has been tested also with H-reflex (H-reflexes show the total motor unit activity) and
motor responses (M-response) and it has been shown that the motor unit population
activated with electrical stimulus as well as the motor unit recruitment order have
changed (Trimble and Enoka, 1991).
Due to this selective recruitment, an increase of up to 44% in the muscular strength
has been observed (Brocherie et al., 2005; Anderson 2009). Theoretically, electrical
stimulus application during a voluntary muscle movement can activate more motor
units compared to the voluntary contraction alone; and it has been reported that this can
led to an increase in the contraction strength and the training programs where electrical
stimulus is used are much more efficient and provide more volume and muscle strength
compared to the separate use of the electrical stimulus and voluntary contraction
programs (Paillard et al., 2005).
1.3. Changes Related with EMS
In this section, the effects of EMS on the muscle, changes in the myofibril
mechanism and energy metabolism, neurophysiologic, tissular and biochemical, blood
flow and capillary changes have studied in consideration of the literature.
1.3.1. Changes in Myofibril Mechanism and Energy Metabolism
For the high level contractions, the basic muscular adaptations are the increases in
actin and myosin (contractile proteins). Both voluntary activation and electrical
stimulation may cause an increase in the contractile protein quantity of the muscle
(Robinson and Snyder-Mackler, 2007).
Animal testing provides useful information about the effects of EMS at the cellular
level. The studies covering chronic low frequency impulses showed that the basic
function elements of the muscles fibers such as (Ca2+) regulating system, myofibril
system, energy metabolism and microvascular system are also affected by EMS
(Callaghan, 2002).
In the contraction produced by the chronic low frequency EMS, the alteration of
the Ca2+ dynamics and then a change from fast to slow characteristic have been
observed. These are ultra structural changes in the cross-sectional area (CSA) and the
significant decreases have been observed in its weight, although the width of the band Z
(this is the reason why it reminds of the ST fibers) and the number of the fibers are
preserved (Pette, 2001). Also, it seems that the chronic stimulation causes the complete
reorganization of the myofibrillary proteins during the conversion of the sarcomere
from fast to slow (Callaghan, 2002). Furthermore, it leds to continous increase of the
intracellular calcium and activates the calcium regulating enzymes such as calcineurin
and calmodulin-inked protein kinase (CaMK) (Wu et al., 2000).
Low frequency EMS during 48 hours may cause significant decrease in the
715
maximum Ca2+
use capacity in the sarsarcoplasmic reticulum and the initial rate. Longer
stimulation causes more significant changes and accompanied with the decrease in the
Ca2+ activity to reach ATPaza (Pette, 2001). Also, with chronic low frequency EMS, a
significant increase in the aerobic-oxidative capacity of the FT muscles and a five times
increase in the capillary density may be observed (Brown et al., 1989).
There are important evidences demonstrating that when the exercising protocols
are applied with low intensity, the glycolytic anaerobic metabolism is more significant
in EMS compared to the voluntary exercising due to the formation of the hydrogen ions
and phosphocreatine catabolism (Hultman and Spriet, 1986; Vanderthommen et al.,
2003). Additionally, it has been shown that the glucose carrying activity is higher in FT
fibers compared to ST fibers when EMS is applied (Roy et al., 1997). EMS may be a
better approach to increase the glucose carrying activity to the skeletal muscle without
intensive voluntary exercising. Also, the functional and enzymatic adaptations in the
skeletal muscle response against the chronic low frequency EMS have been observed in
the human subjects (Chilibeck et al., 1999; Mohr et al., 2001; Nuhr et al., 2003).
1.3.2. Neurogenic Changes
Although EMS is accepted in general as a technique used to activate the muscles
without activating the nervous system, the mutual transmission of the action potentials
through the stimulated axones (Maffiuletti et al., 2006), the dose-response relation
between the activation of the selected brain sections by quadriceps stimulation (Smith et
al., 2003), the cross effects of the training at the same time (Hortobágyi et al., 1999;
Maffiuletti et al., 2006) showed clearly that EMS activates the neural system. All these
results demonstrate that the electrical stimulation does not completely bypass the
peripheral system.
However, in the recent statements about the neurophysiologic effects of EMS, it
has been reported that when the normal muscles are trained through electrical
stimulation, the initial rate of strength gain is fast without any change in the muscle
volume, and this is an indicator showing that the adaptive mechanisms are neural.
Another possible mechanism is the increasing spinal motor neuron pool activation. It
has been reported that the motoneurons regulate the strength gain through the
simulation of the afferent neurons and it is associated with a long term potantialization
together with a snaps sensitivity due to the stimulation of the afferent nerve fibers, and
thus the strength gains can be preserved for a couple of weeks even if the training is
stopped and this has a long term potantialization (Hortobágyi, 1996; Gondin et al.,
2006; Jubeau et al., 2006). These useful effects of the electrical muscle stimulation is
accompanied by the increasing blood flow in the intramuscular and peripheral soft-wall
vessels and thus, the pumping activity of the muscles increases (Hortobágyi, 1996).
Various EMS studies claiming that the strength gains are associated with the
neural factors rather than the changes at the muscular level covers a period of 4 weeks
or less (Singer, 1986; Maffiuletti, Pensini, and Martin 2002; Malatesta et al., 2003). For
example Maffiuletti, Pensini and Martin (2002) after an EMS training of 4 weeks, the
significant increase in the maximum voluntary contraction (MVC) has been associated
with the increase in the muscle activation and in the EMG (electromyography) activity,
(Gondin et al. (2005) and upon a research where the effects of the 4 and 8 weeks EMS
trainings on the neural and muscular adaptations of the knee extensor muscles, it has
been reported that after a 8 weeks EMS training, quadriceps MVC tork increase is
716
associated with both muscular and neural adaptations. The first 4 weeks period being
the start of the strength increase, the second 4 weeks period has led to more strength
gain. Similarly, after a 5 weeks EMS training of the plantar flexor muscle, the increase
in the voluntary tork has been associated with the spinal level adaptations and an
increased voluntary function in the supraspinal centers (Gondin et al., 2006a).
Upon the neuromuscular electrical stimulation training of fiwe weeks and then the
following detraining period of five weeks, it has been observed that the neural
adaptations affected by the training continue after the detraining and thus this shows
that the neural changes are preserved for long term and do not affect the H-reflex
elements (Gondin et al., 2006b).
Maffiuletti et al. (2003), have shown in their study that the EMS training of the
plantar flexor muscles (4 weeks-16 isometric EMS sessions - 75Hz) does not affect the
alpha motor excitability and presynaptic inhibition as is the case with the H-reflex.
Additionally, in a research where the H-reflex and M-response in the electrical
stimulation are studied (Trimble and Enoka, 1991) it has been demonstrated that EMS
directly activates the large afferent axones and provide cutaneous feedback that changes
the motor unit population activated during the H-reflex.
In a study where the central and peripheral fatigue caused by a typical EMS
session (75Hz) is examined, it has been reported that the significant decrease in the
maximum voluntary contraction strength after the EMS is associated with the
significant decrease in the center activation and both central and peripheral factors
contribute to the fatigue, and the neuromuscular propogation weakness has been
demonstrated for the muscles having higher FT fiber percentage (Boerio et al., 2005).
1.3.3. Tissular and Biochemical Changes
The use of muscular biopsy has provided important evidences about the cellular
changes caused by EMS in human muscles and especially in the quadriceps muscle. As
reported by Callaghan (2002) in the first studies (1980s), the muscle fiber area and the
fiber type composition of the healthy quadriceps were not changed by 200Hz EMS;
whereas in other studies, 50 Hz modulated 2500 Hz “Russian” EMS protocol caused a
significant decrease in the FT fiber area, but no change has been observed in terms of
the fiber type distribution. However, the post-stimulation decrease in the fiber area in
the healthy subjects is the contrary to that observed in the patients with knee injury after
the stimulation and this has been explained by the variations in the mechanisms covered
by the strength training. Furthermore, Callaghan (2002) has indicated that the neural
factors or enzymatic changes in the healthy subjects can be much more significant
compared to the fiber type changes and in certain studies no significant change has been
observed in the enzyme activity involved in the contraction process, whereas in certain
studies, after the knee and quadriceps immobilization of 5 weeks, the decrease in the
succinate dehydrogenase activity (an indicator of the mitochondrial oxidative activity)
observed in the patients has been significantly slowed down after EMS. On the other
hand, after the chronic low frequency EMS (8Hz, 8 hours daily) applied to the
quadriceps for 8 weeks, a significant increase in the aerobic enzyme activity has been
observed and no change has been seen in terms of the anaerobic indicators.
It is important to note that the different results obtained from the different studies
are related with the different EMS parameters. For example, in a study regarding the
healthy human vastus lateralis phenotype after EMS (Perez et al., 2002), it has been
717
seen that while short periods (45-60Hz for 6 weeks, 3 days a week, 30 minutes each
day, 300 µs) reduces completely the percentages of other fiber type, it increases the FT-
a fiber percentage.
The chronic muscle weakness is related with the decrease in the muscle protein
synthesis and the results obtained from the atrophic muscle studies show that EMS
causes changes in the muscle physiology at the cellular level and it protects the protein
synthesis in the atrophic muscles especially after the immobilization (Callaghan, 2002).
1.3.4. Changes in the Muscle Blood Flow and Capillary Structure
Various studies showed that exercising with EMS can increase the blood flow in
the stimulated muscles in parallel with the voluntary exercising (Currier et al., 1986;
Walker et al., 1988, Levine et al., 1990). What is interesting is that Vanderthommen at
al. (1997) have reported that compared to the voluntary exercising with the same work
load, the blood flow is higher during EMS. Since in all of these studies (Currier et al.,
1986; Walker et al., 1988; Levine et al., 1990; Vanderthommen et al., 1997) the
disturbing tetanic stimulation frequencies (35-100Hz) have been used, it is likely that a
vasoconstriction that resists to the expected increase in the blood flow occurs (Walker et
al., 1988).
Kim et al. (1995) has reported that pulmonary O2 use being same for both
exercising forms, the ventilator coefficient is higher in EMS compared to the voluntary
exercising; that the leg blood flow and O2 use are similar for both exercising forms and
the heart rate and average blood pressure are partially higher in EMS. Other results
obtained show that the lactate and ammonia flows in the leg are higher in EMS and they
increase with the increasing exercising intensity; that the muscles’ glucose use is similar
for both exercising forms; that the femoral venous potassium (K+) concentration
increases with the exercising intensity and higher in EMS.
In animals, the histochemical characteristics of the fast muscle fibers become
similar to those of the slow muscle fibers after low frequency EMS and the fast muscles
gain higher capillary density and more fatigue resistence (Callaghan, 2002). When these
muscles are stimulated with low frequency (10 Hz continous) for 2-4 days (8
hours/day), it has been shown that the fast glycolytic transforms into fast oxidative
fibers and that after 4 days of stimulation, this transformation is much higher and that
the number of the capillaries is higher in the stimulated muscles (Hudlicka, 1982). It has
been reported that an EMS training for 21 days regarding the human triceps surae
muscles (50 Hz and 2500 Hz alternate current) develops the capillary source (Perez et
al., 2002).
2. EMS IN MUSCLE STRENGHTENING
The basic problem about the muscle stimulation literature is the way how EMS
changes the muscular performance in the EMS or in the EMS and voluntary exercising
combination as compared with the voluntary exercising.
The strength response of the skeletal muscle against the stimulation depends on the
intensity and frequency of the stimulation. A single shock on a muscle results in a
single twitch in 200 milliseconds. If the stimulation frequency is increased 10 to 20
impulses per second, the muscle contraction is fragmental or twitch like. Unlike this,
when a muscle is stimulated with high frequency, the contraction becomes smooth and
the strength production peaks (tetanus). However, the muscle get tired fast (Hortobágyi,
1996; Starkey, 2013).
718
Under the natural conditions, while the motoneurons are activated
unsynchronised, the artificial EMS signals are synchronised. In the natural stimulation,
the motor units produce the muscular strength hierarchically (size principle). A second
natural strength regulation form is the increase in the stimulation ratios of the motor
units at the high contraction levels (Hortobágyi, 1996). However, in the electrical
stimulation, the larger motor units are recruited first due to their low resistence.
Therefore, in the artificial EMS aiming higher strength production, higher stimulation
frequencies must be used. However, the muscle would get tired inevitably (Hortobágyi,
1996). The high frequency stimulation (> 70Hz) causes deficiency in the nerve-muscle
intersection and the muscle get tired fastly. It has been reported that the appropriate
frequency is of the similar rate to the normal motor unit discharge frequency (20-50 Hz)
produced during the voluntary activity and the very low frequencies do not guarantee
the muscle contraction (Petrofsky, 2004).
Bickel et al. (2003) has shown that the acute EMS is sufficient to stimulate the
responses at the molecular level. This kind of changes show that the hypertrophy
process has started in the muscles. Therefore, after multiple EMS sessions, the changes
at the muscular level can be expected. However, the effect of an EMS training program
on the muscle hypertrophy is still ambigous in the literature depending on the training
duration (Singer, 1986; Stevenson and Dudley, 2001; Gondin et al., 2005) and selected
EMS parameters (Stevenson and Dudley, 2001). For example, in a study (Stevenson
and Dudley, 2001) an impressive increase is observed in the quadriceps muscle volume
after an EMS training of 8-9 weeks, whereas in the studies covering 4 weeks EMS
programs, no such changes have been reported (Singer, 1986). Therefore, it has been
assumed that an EMS program lasting more than 4 weeks can provide muscle
hypertrophy (Obajuluwa, 1991).
In all recent whole body EMS studies, it has been reported that the obtained
strength gains are quite low (Filipovic, 2011).
2.1. EMS or Isometric Exercising
The study results have revealed that the isometric strength can be increased up to
50% with the electrical stimulation of the knee extensor muscles (Hortobágyi, 1996).
However, the studies conducted on the healthy skeletal muscles show that the strength
development is not as high as in the atrophic muscles.
In the publications comparing the isometric exercising and EMS (Laughman et al.,
1983, Mohr et al., 1985; Robinson and Snyder-Mackler, 2007), despite the significant
differences in the methodological approaches, no difference has been observed in terms
of the strength/tork gains between the quadriceps isometric exercising and EMS for the
healthy subjects. Only Mohr et al. (1985)
have found a significant development with
regard to the quadriceps muscle with the isometric exercising (14.7%). In the study that
shows the voluntary isometric training is more efficient than EMS in terms of the
strength increase of the elbow flexor muscles (Holcomb, 2006) the significant
ineffectiveness of the EMS is associated with the exercising intensity.
2.2. EMS or Isokinetic Exercising
In the studies directly comparing the EMS and isokinetic exercising for the healthy
quadriceps muscles (Halbach and Straus, 1980; Nobbs and Rhodes, 1986), it has been
reported that a descriptive development in the quadriceps muscle strength (42% for the
exercise group, 22% for the stimulation group) can be provided. What is interesting is
719
that Nobbs and Rhodes (1986) have reported that there is no significant difference for
100°/second and 180°/second angular speeds and the strength gain is recorded at the
speeds less or equal to 30°/second and 0°/second training speeds.
As reported by Lloyd et al. (1986), a significant strength development in the EMS
and isokinetic exercising groups is observed for each angular speeds and knee joint
angles. Although there is no difference between the groups, the highest strength
increase has been observed in the isokinetic group, whereas the development in the
EMS group has been revealed in the isometric and slow isokinetic contractions.
Similarly Halbach and Straus (1980) has found that although all of the groups have
shown significant strength increase, isokinetic training have provided more strength
gain compared to EMS. In this study, the isokinetic training has been applied with
different speeds and tested for a single speed (120°/second).
2.3. Combination of EMS and Isometric / Isokinetic Exercising
In some studies where the voluntary exercising has been combined with EMS, the
objective was to define the EMS effects. All of these studies have revealed clearly that
combining exercising and EMS simultaneously is much more efficient than exercising
alone (Convery et al., 1994; Burkett et al., 1998). Additionally, this has been concluded
regardless whether isometric or isokinetic exercising were used. Therefore, although it
has been reported that the combination of these two forms do not provide any gain in
the healthy quadriceps muscles (Lloyd et al., 1986) the recent studies have proved the
opposite. For example, Callaghan (2002) has reported that an isometric constraction in
the 45° knee flexion with or without EMS, an isotonic concentric activity from 90° to
complete knee extension and a squat jump comparison; 100 Hz EMS during 0.8
seconds has improved the isometric tork for a ratio of 23% and the isotonic tork for a
ratio of 4%; however squat jumps with multiple joint activities have not caused any
difference.
Dervisevic, Bilban and Valencic (2002) have reported that the isokinetic training
combined with the low frequency EMS is a much more efficient method to develop the
strength of the quadriceps, compared to the low frequency training and to the isokinetic
training alone.
3. MUSCLE ENDURANCE AND EMS
The limited number of the studies examining the effects of the EMS training on the
muscular training shows that there is a need for studies on human. Robinson and
Snyder-Mackler (2007) have indicated that EMS training does not have a significant
effect on the abdominal muscle in terms of the muscular endurance. Hartsell’s (1986)
study showed an increase in the quadriceps endurance upon stimulation program;
however these small increases have not been more significant than those obtained by
exercising alone.
According to Robinson and Snyder-Mackler (2007), the basic problem for defining
the effects of EMS on the muscular fatigue is the fact that the studied EMS training
programs are based on the voluntary training programs and there is no clinical study
showing that the voluntary endurance training principles (low intensity contractions,
high numbers of repetition) were used in the EMS training to improve the muscular
endurance.
However, with reference to the study conducted by Thériault et al. (1994),
Callaghan (2002) has reported that when much lower frequencies such as 8 Hz are used
720
on the animal models, together with an increase in the aerobic oxidative enzyme
indicators of 25%, an improvement in the quadriceps endurance and a significant
increase in the total quantity of the knee extension training have been observed.
Callaghan (2002) who has indicated that the improvements in the endurance capacity
are provided with the non uniform stimulation forms, has reported in 1995 with
reference to the studies of Oldham et al. that the non uniform neuromuscular
stimulation model used for the quadriceps of the old patient with osteoarthritis is better
than uniform EMS. Also, the study by Lopez-Guajardo et al. (2001) has shown that low
frequency (10Hz) stimulation (6 weeks, 30 minutes each day) applied to the tibialis
anterior muscle of the rabbits has provided a significant increase in the endurance
capacity of the muscle.
Perez et al. (2003) have reported that in human, the chronic electrical stimulation
sessions (a couple of hours each day) via the skin may increase the oxidative capacity
and capillarization of the FT fibers of the muscle and may cause some fiber transitions
among the FT subfibers. However, Perez et al. (2003) have emphasized that in several
studies showing the significant effects of EMS on the human skeletal muscles, the
protocols that have been applied are unrealistic and difficult to apply under sports
training conditions and in clinics and that the sessions are too long (a couple of hours
per day) and the used frequency currents (a duration of approximately 100 ms pulse, 50-
100Hz) are disturbing.
The experimental results obtained from the studies involving low frequency EMS
on healthy people’s muscles show that the oxidation potential of the stimulated muscles
increases. For example, in the study that shows that low frequency electrical stimulation
(8Hz) for 6 weeks improves the fatigue resistence of the knee extensor muscle
significantly, the citrate syntasis activity, the capillary number per FT-a and FT-b fibers
and the percentage of the FT-a muscle fibers in the vastus lateralis muscle have been
significantly increased (Thériault et al., 1996).
4. STIMULATION PARAMETERS
Nowadays, the stimulation current is transmitted by fixing the electrodes of
different structure and materials on the skin covering the motor nerve (motor point).
Even if the stimulation is applied on the exact motor point, the strength production of a
muscle varies according to the stimulus parameters. Other factors to be considered are
the stimulus waveform manipulation (rectangular, sinusoidal, triangle, symmetrical,
asymmetrical, etc.) as well as its duration, intensity and frequence (Hortobágyi, 1996).
One of the issues that prevents to reach a consensus about the EMS is the
extensive variations in the stimulation parameters. However, it has been reported that
the success of a training program depends on the allowable stimulation intensity,
frequency, and the durations of the entire program and each session (Hortobágyi, 1996).
The most important parameter is the frequency and generally is grouped as low,
medium and high frequency (Callaghan, 2002). The conducted studies have revealed
that the most appropriate program for the EMS training is three times a week, two times
a day for 30 minutes and with an intensity of 0.4-30 mA (Boonyarom et al., 2009).
In addition to this, while examining the efficiency of EMS with regard to various
knee joint angles, several researchers use the standardized 60° knee flexion position
(Laughman et al., 1983; Selkowitz, 1985; Mohr et al., 1985; Soo et al., 1988). Other
researchers emphasize various knee flexions changing between 15° and 90° (Obajuluwa,
721
1991). Also, the hip flexion is constant for both application and evaluation. When
multiple angles are examined, it has been seen that strength improvement occur in the
closest test angle (Maffiuletti et al., 2000). The variations in the results (1-49.7%) are
arisen probably from the differences in the methodological approaches and stimulation
parameters.
4.1. Waveform
Different waveforms (i.e. the form of impulse) are used in EMS (Laufer et al.,
2001) and the improvement is determined by the nature of the waveform (Kantor et al.,
1994).
According to Callaghan’ın (2002), after the first trainings, during high frequency
sinusoidal stimulation fatigue occurs and the strengthening effects decline. While
Agrawal et al. (2008) did not find a significant strength improvement after the 2.5 kHz
variable current stimulation, whereas in another study it has been reported that the
improvement in the muscle strengthening was 47.7%. Similarly in the studies where 50
Hz stimulation is used without Carrier waveform, different results have been obtained.
The muscle strengthening reached in these studies vary between 0% (Mohr et al., 1985)
and 48.5% (Lai et al., 1988).
In a study where the efficiencies of the three waveforms were compared, it has
been seen that the monophasic and biphasic orthogonal waveforms are more efficient
than the polyphasic waveform in terms of tork production and that these two waveforms
cause less fatigue (Laufer et al., 2001). In another study, it has been reported that the
bipolar interferencial current (2500 Hz carrier frequency and 80 Hz amplitude
modulation frequency) and low frequency current (symmetrical biphasic) can be used to
improve the quadriceps muscular strength and the sensed discomforts are similar for
these two waveforms (Bircan et al., 2002). However, it has been indicated that the
optimum waveform is biphasic since it produces higher muscular strength and causes
less pain (Petrofsky, 2004).
4.2. Pulse Duration
Although the pulse durations longer than 60 micro seconds (μs) probably activates
the pain fibers, the durations over 200 300 μs produce a much stronger contraction
(Lake, 1992) and a pulse duration of 200 to 400 μs specifically recruits motor nerves
(Starkey, 2013). Also, an interval of 200 to 400 μs is applied in the human muscular
trainings (Cheing et al., 2003); (Filipovic et al., 2012).
It has been reported that in general, a larger electrode pad structure allows better
stimulation tolerence and a current interval of 250-300 μs results in minimum pain
response (Petrofsky, 2004). Currently, the clinicians and researchers generally use the
symmetrical biphasic waveform and a current interval of 300 µs (Alon and Smith, 2005).
Also, it has been reported that if the frequency and intensity are kept constant, the
minimum frequency and maximum pulse duration would maximize the performance
(Kesar and Binder-Macleod, 2006).
4.3. Duty Cycle
In general, this is related with the “on/off” ratio. The “on” phase is the period
when the impulse is transmitted to the muscle. The “off” phase is the period between
the consecutive “on” phases (Lake, 1992). This parameter is important in terms of
resisting against the early muscle fatigue and providing a rest period between the
722
contractions (Binder-Macleod and Snyder-Mackler, 1993).
Although the exact relationship between the fatigue and stimulated contraction
duration and rest for most of the muscles (Robinson and Snyder-Mackler, 2007),
Binder-Macleod and Snyder-Mackler (1993) have shown that the contraction intensity
and frequency effect the fatigue directly. However, their effects are independent from
each other. to reach the high strength levels while strengthening, the frequencies must
be higher than the critical fusion frequency (tetani) (higher frequency, higher
contraction causing more fatigue). The high contraction intensity provokes also the
fatigue (Robinson and Snyder-Mackler, 2007).
A training cycle comprising of the shorther “on” and longer “off” durations are
useful to protect the muscle against the fatigue and thus, to increase the muscle strength
(Matsunaga et al., 1999). It has been observed that longer resting periods are required to
minimize the muscle fatigue in higher frequencies, compared to the medium
frequencies such as 30Hz (Callaghan, 2002). Furthermore, it has been indicated that in
order to avoid the fatigue, the training cycle must be at least 1:5 and for a successful
muscular strengthening a training cycle of 1:1 (4 seconds on, 4 seconds off; 15 seconds
on, 15 seconds off) and 1:5 (10 seconds on, 50 seconds off) is suggested (Mohr et al., 1985).
4.4. Intensity and Length Stimulation
The current intensity (amplitude) is measured with various methods but defined
often as miliampere (mA) (Callaghan, 2002). The strength of the contraction increases
as the amplitude of the current increases and there is a linear relation between the higher
contraction intensity and higher intramuscular changes (Starkey, 2013; Halbach and
Straus, 1980).
The stimulation intensity can be of a value corresponding to a specified voluntary
isometric contraction strength or mostly of a value corresponding to the tolerence of the
subject (Paavo, 2003). It has been reported in many studies that depending on the
subject tolerence, the current intensity increased gradually may vary between 30-90 mA
and that this current intensity does not cause a serious discomfort for the subjects
(Maffiuletti, Pesini, and Martin 2002).
Callaghan (2002) has reported that the maximum pain rate is experienced for the
stimulus intensities corresponding to the 47.1, 70.3 and 42.8 % of the maximum
voluntary isometric tork (MVIT). However, many studies covering the quadriceps
stimulation application do not define higher stimulation levels (40-80% MVIT).
The basic difference regarding the studies where the effects of the EMS and
exercising on the muscle strength are similar (Caggiano et al., 1994; Kubiak et al.,
1987) is the contraction intensity reached with EMS or exercising. This supports once
again that the higher activity and stimulation levels would provide more strength gains.
However, the strength gains in some other studies show that the strength gains are not
always related with the contraction intensity of a muscle. While the exercising group in
the Laughman et al. (1983)’s has worked at average 78% maximum voluntary ısometric
contraction (MVIC), the stimulation group has worked at average 33% MVIC.
Nevertheless, similar results have been obtained from both groups.
In the clinical environment, the maximum comfortable intensity tends to be less
than 30% of the MVIC (Starkey, 2013) and the initial level of a stimulation intensity
that would provoke a reasonable contraction for affecting the intramuscular changes is
30% MVIT. Besides, the main restriction seems to be the current intensity that can be
723
easily tolerated by the patient. This depends on the skin resistence and capacitive skin
impedence (Lake, 1992). This is important because the patients using constant
frequency stimulators with 35 Hz and higher (approximately 100Hz) would encounter
problems while trying to produce strong contractions easily at higher intensities. Also,
the cold application prior to treatment increaeses the maximum output tolerated by the
patient, but does not translate increased torque production (Starkey, 2013).
4.4.1. Length of Treatment
The examination of the application programs reveal that there are significant
differences in terms of the daily stimulation quantity and the length of the experimental
programs. While some of the studies are too short such as 5 days (Vinge et al., 1996)
and some of them are long as 10 weeks (Obajuluwa, 1991) the common application
period is 6 weeks (Draper and Ballard, 1991; Snyder-Mackler et al., 1991; Snyder-
Mackler et al., 1995).
Due to the differences in the stimulation characteristics and training protocols, the
number of the electrical stimulation sessions required for providing strength gain is
quite variable. While some researchers have obtained the significant strength gain after
a few period of time such as 10 sessions, others reached the significant increases in the
strength after 12-25 training session (Mohr et al., 1985). However, when used 4 weeks
and 3 times a week, it is possible to obtain significant effects (Parker et al., 2003). In
summary, regardless of the EMS method used, the analysis revealed that a stimulation
period in a range of 4–6 weeks (3.2 ± 0.9 sessions per week, 17.7 ± 10.9 minutes per
session, 6.0 ± 2.4 seconds per contraction with 20.3 ± 9.0% duty cycle) shows positive
effects for enhancing strength parameters, jumping and sprinting ability, and power.
Therefore, the results of trials using whole-body EMS methods showed that a duration
of 15 minutes (2 sessions per week over a 4-week stimulation period) can be assumed to
be sufficient for stimulation to activate strength adaptations and thus increasing strength
abilities (Filipovic et al., 2011).
4.5. Low Frequency Stimulation Versus High Frequency Stimulation
Low frequency stimulation (characteristically between 1-10 Hz) is used to improve
the fatigue characteristic of a muscle. On the other hand, if the stimulation is used to
provide the strength gain, it causes fatigue. A stimulation regime comprising
consecutive high frequency periods together with the low frequency stimulation can be
much more advantageous. (Callaghan, 2002).
It has been reported that the low frequency stimulation increases the fatigue
resistence during the isometric rhythmic or continous contractions of the muscles and
this reaches the peak after 4 weeks (Shenkman et al., 2007). Also, it does not produce
significant change in the maximum voluntary strength or may cause a slight decrease
(Nuhr et al., 2003).
The experimental results show that the low frequency electrical stimulation causes
the oxidation potential of the stimulated muscles (Thériault et al., 1996). This is an
important characteristic for keeping the activity level in the clinical applications.
However, there is a significant decrease in the muscle mass (Salmons and
Hendricksson, 1981), contraction speed and ability to produce strength (Jarvis, 1993). It
has been accepted that 30 or 50 Hz frequency stimulation can produce higher tork value
compared to the 10Hz stimulation (Lieber and Kelly, 1993). Although the high
frequency stimulation improves the muscle strength theoretically, since it may cause
724
muscle fatigue if no sufficient resting period is provided, the frequency of the electrical
stimulation used for the fatigued muscles are low in general and the purpose is rather
the recovery of these muscles (Raymond et al., 2007; Maffiuletti et al., 2011; Babault et
al., 2011). Again the low frequency is preferred for the muscular endurance trainings.
Likewise, it is known that the long term low frequency electrical stimulus makes the FT
fibers gain ST fibers’ characteristic. However, the evidences claiming the over
stimulation causes muscular fatigue are conflicting and probably this is due to the use of
different methodological approaches. For example, it has been reported that in human
muscle 100 Hz uniform high frequency stimulation has a few effects on the endurance
together with an increase in the contractile speed; and differently, the feline FT muscles
become slower at 100 Hz stimulation (Callaghan, 2002). High frequences such as 30-50
Hz are above the natural stimulation frequency of the motor units and the regular
stimulation frequencies of the motor units in daily life vary between 15Hz – 25 Hz (De
Luca, 1997) and therefore, the muscle cannot cope with the extra energy demands
(Callaghan, 2002). Nevertheless, it has been reported that the contraction intensity near
to maximum has been reached with a stimulation of 50 Hz (Hultman, 1995). Likewise,
the fast motor unit nerves in the skeletal muscle are discharged at high frequencies such
as 40-60Hz (for those in the slow motor units it is 10Hz) (Bigard et al., 1991).
The frequence specific stimulation studies involving nerve free animal muscles
have supported the idea of using low frequency for the slow muscles and high
frequency for the fast muscles (Kit-Ian, 1991). It has been confirmed that the 100 Hz
frequency used for the FT fibers slows down the atrophy in the FT fibers and restores
the normal contraction speed and tension. With regard to the high frequency stimulation
applied to the ST fibers, it has been reported that this can reduce the fatigue resistence
and cause muscle transformation from slow to fast. On the other hand, it has been
reported that applying low frequency stimulation to the fast fibers may provide some
beneficial effects that improve and preserve the oxidative enzyme activities and
improve the endurance (Kit-Ian, 1991).
In addition, it has been indicated that certain restrictions of the electromyostimu-
lation such as random recruitment can be minimized by adding the contribution of the
central pathways (reflexive recruitment of spinal motoneurons by the electrically
evoked afferent volley) and that the pulse frequency should be as high as 100 Hz for
this purpose (to increase the rate at which the sensory volley is sent to the spinal cord
and supra-spinal centres) (Maffiuletti, et al., 2011).
5. USE IN THE SPORTS TRAINING PROGRAMS
The effects of EMS on the strength gain have been tested in various training
programs. For example, a stimulation period of 12 weeks has increased the muscular
strength and power of the rugby players (Babault et al., 2007). However, it did not have
any effect on technical rugby skills such as spurt and sprint. In another study, the
combination of the EMS and plyometric training combination improved the maximum
strength of the quadriceps femoris as well as the vertical jump and sprint (Herrero et al.,
2006); however, EMS alone slowed down the sprint speed but did not exceed the gains
obtained by the combination with the plyometric training. The current studies by
Herrero et al. (2010a, 2010b) emphasize that in the endurance trainings, the
superimposed electrical stimulation applied during the concentric phase of the
movement is efficient on the strength improvement; however, it has been indicated that
725
when the objective is to improve the anaerobic performance, the electrical stimulation
must be used isometrically. In the study by Requena et al. (2005) it has been shown that
the EMS combined with fast concentric (1800/s) and eccentric training increases the
maximum concentric movement. With regard to the ice hockey, while 3 weeks
electrical stimulation has significantly increased the isokinetic strength of the knee
extensors for the eccentric and concentric speeds, it has negatively affected the vertical
jumping performance (Johnston 2004; Brocherie et al., 2005). In another study
involving the volleyball players (Malatesta et al., 2003), the required level of effect in
terms of the jumping performance has not been reached after 4 weeks of EMS training.
On the contrary, it has been seen that a 4 weeks EMS program combined with the
plyometrics is beneficial to improve the jumping skills among the volleyball players
(Maffiuletti et al., 2002). In the study involving the basketball players, the EMS that has
been applied as as part of the short term strength training (4 weeks) has improved the
strength of the knee extensor and squat jumping ability (Maffiuletti et al., 2000). The
study by Pichon et al. (1995) has shown that after an EMS program of 3 weeks, the
swimming performance increases. An interesting result is that a 2 weeks
complementary electrical stimulation program has positive effects on the paddling
technique characterized by the power/time curve for the paddlers (Changsheng et al.,
2002). However, it has been reported that most of the studies about this subject are
weak methodologically (Dehail et al., 2008). With meta analysis, Bax et al. (2005)
showed that the electrical stimulation is very efficient for strengthening the quadriceps
femoris only compared to the control who does not exercise and that even if the
stimulation is combined with the voluntary activity simultaneously, it is much more
efficient. It has been reported that xcept those cases where it is combined with the
eccentric training, the electrical stimulation is not significantly efficient in the classical
training (Dehail et al., 2008). As summarized by Vanderthommen and Duchateau
(2007), the strength gains due to the electrostimulation are not much higher than those
obtained by the trainings covering the voluntary contractions. Because these gains are
probably due to the intensity of the stimulation. Even if there is a standardized method,
the use of the comfortable currents is very important. As a complementary element of
the classical strengthening programs for the healthy individuals and athletes, especially
when applied simultaneously with the voluntary contractions, EMS seems much more
efficient. The basic advantages of EMS are: (1) increasing the work load of the muscle
as a complementary element of the classical training and (2) causing a different
contraction model than the model that occurs during the voluntary contraction (Paillard,
Noe, and Edeline 2005; Vanderthommen and Duchateau, 2007). Consequently, even if
the strength gains are transferrable to the sports activities, the negative results (Herrero
et al., 2006) indicate that the skill training is always needed to improve the muscular
coordination (Requena et al., 2005).
EMS has the potential to serve as a post-exercise recovery tool for athletes, since
its acute application may increase muscle blood flow and therefore metabolite washout
which could in turn accelerate recovery kinetics during and after exercise (Babault et
al., 2011). However, since there are studies that show different effects of EMS on the
recovery process (Barnett, 2006), the relation between EMS and recovery should be
further examined.
Recently, the efficiency of the electrical stimulation as an exercise for preventing
the muscle loss or increasing the muscle mass in gravity-free environment are studied.
726
In the studies based on the electrical stimulation of the antagonists together with the
voluntary agonist muscle contractions (Ito et al., 2004; Iwasaki et al., 2006; Matsuse et
al., 2006), it has been shown that the electrical stimulation can be used instead of the
traditional weight training without need to the resistence equipment and stabilization.
Ito et al. (2004) has reported that the hybrid training they have used during 4 weeks and
3 times a week is efficient to provide strength increase in the gravity-free environment
(5000 Hz Carrier frequency and 20 Hz burst-wave stimulation frequency). Iwasaki et al.
(2006) have reported that the hybrid training they have applied during 6 weeks, 3 times
a week (voluntary knee extension and flexion simultaneously with the electrical
stimulation) is comparable to the weight training among the healthy individuals in order
to improve the knee extension strength and this method can be beneficial for the
bedridden persons or space journeys. In the follow up study that gave similar results, it
has been proved that the hybrid training (8 weeks / 3 times a week) provides significant
strength increases and the strength gains continue longer compared to the isotonic
weight training and electrical stimulation alone. It has been indicated that the increases
in the muscular cross sections are comparable with the other two methods (Matsuse et
al., 2006). It has been shown that in long term space journeys, as a precaution against
the muscular strength and muscle mass loss, the low frequency electrical stimulation
(15 Hz, 4.5 weeks, six times a week; each session lasts 6 hours) on the stretched
muscles causes an insignificant decrease on the muscular strength and an increase in
both types of muscular fiber cross section (Shenkman et al., 2007).
6. CONCLUSIONS
The animal studies have provided detailed evidences about the chronic low
frequency stimulation effects at the vascular, cellular and metabolic levels. Currently,
although it has been determined that the fast muscle fibers are transformed into slow
fibers upon low frequency EMS, it is still difficult to prove the transformation from fast
to slow in animal models.
With regard to human, it seems that there is a concensus about the benefit of the
EMS regarding the functions measured by the walking analysis and some functional
tests. Also, it has been accepted that the quadriceps atrophy measured with the cross
sectional area can be reduced with EMS. However, with regard to the human studies,
insufficient and conflicting results have been reported in terms of MVIC, MVIT,
isokinetic strength, femur periphery by tape measurement, muscle protein and enzyme
activity, fiber type composition, fiber type cross sectional area and fiber type ratio.
Also, the literature shows that when the muscle is weak after the immobilization,
the EMS will provide a medium level strengthening, however when it is applied to the
healthy or strong muscles, it will not provide the required improvement. When the
literature is examined, the various reasons for these differences are seen.
Consequently; significant evidences demonstrating EMS’s effects on the human
muscles in terms of the cellular changes have been provided and it has the potential to
serve as a sport tarining tool for developing physical performance.
7. RECOMMENDATIONS FOR FUTURE RESEARCH
To better understand the effect of application on sport performance, future research
might consider:
Developing experimental models where the needs of the athlete and the specific
727
components of the training are integrated.
Developing complex training models including EMS in order to simultaneously
improve the characteristics that are difficult to combine in a single training program due
to the different demands (such as muscular strength and endurance).
Developing new experimental models that realize the potential benefits of the
EMS on recovery in order to tolerate the training loads and increase the training effects.
Developing new models covering the whole body applications with different
stimulation parameters.
Acknowledgements: No sources of funding were used to assist in the preparation of
this review. The authors have no conflicts of interest that are directly relevant to the
content of this review.
REFERENCES
Agrawal A, Zutshi K, Ram CS, Zafar R, Bhaduri SN, Chengappa RK. (2008). Strengthening
of muscles with 1 KHz alternating current. Indian Journal of Physical Medicine and
Rehabilitation, 19 (2):53-55.
Alon G, Smith GV. (2005). Tolerance and conditioning to neuro-muscular electrical
stimulation within and between sessions and gender. Journal of Sports Science and
Medicine, 4, 395-405.
Anderson Owen (2009), How useful is electrical stimulation in preventing detraining in
inactive muscles? [e-journal], Available at:
http://www.sportsinjurybulletin.com/archive/electrical-stimulation.html (accessed:
17.10.2012)
Atherton, P.J, Babraj J.A, Smith K, Singh J, Rennie M.J, and Wackerhage H. (2005).
Selective activation of AMPK-PGC-1α or PKB-TSC2-mTOR signaling can explain
specific adaptive responses to endurance or resistance training-like electrical muscle
stimulation. The FASEB Journal, FASEB.
Babault, N, Cometti, G, Bernardin M, Pousson M, Chatard JC. (2007). Effects of
electromyostimulation training on muscle strength and power of elite rugby players. J
Strength Cond Res, 21(2):431-7.
Babault, N, Cometti, C, Maffiuletti, N.A, Deley, G. (2011). "Does electrical stimulation
enhance post-exercise performance recovery?". European Journal of Applied
Physiology 111 (10): 2501–7
Barnett A (2006). Using recovery modalities between training sessions in elite athletes does
it help? Sports Med; 36 (9)
Bax, L, Staes, F, Verhagen, A. (2005). Does neuromuscular electrical stimulation strengthen
the quadriceps femoris? A systematic review of randomised controlled trials. Sports
Med, 35:191–212.
Belanger, M, Stein R.B, Wheeler G.D, Gordon, T, Leduc, B. (2000). Electrical stimulation:
Can it increase muscle strength and reverse osteopenia in spinal cord injured
individuals? Arch Phys Med Rehabil, 81:1090 –1098.
Bickel, C.S, Slade, J.M, Haddad F, Adams, G.R, Dudley G.A. (2003). Acute molecular
responses of skeletal muscle to resistance exercise in able-bodied and spinal cord-injured
subjects. J.Appl. Physiol, 94:2255–2262.
Bigard, A.X, Canon, F, Guezennec, C.Y. (1991). Histological and metabolic consequences
of electromyostimulation. A literature review. Science & Sports, Volume 6, Issue 4,
pages 275-292.
Binder-Macleod S.A, Snyder-Mackler L. (1993). Muscle fatigue: clinical implications for
fatigue assessment and neuromuscular electrical stimulation. Phys Ther, 73(12):902-10.
728
Bircan C, Senocak O, Peker O, Kaya A, Tamcı SA, Gulbahar S, Akalin E. (2002). Efficacy
of two forms of electrical stimulation in increasing quadriceps strength: A randomized
controlled trial. Clinical Rehabilitation, 16: 194–199.
Boerio D, Jubeau M, Zory R, Maffiuletti NA. (2005). Central and peripheral fatigue after
electrostimulation-induced resistance exercise. Medicine & Science in Sports &
Exercise, Volume 37(6), pp 973-978.
Boonyarom O, Kozuka N, Matsuyama K, Murakami S. (2009). Effect of electrical
stimulation to prevent muscle atrophy on morphologic and histologic properties of
hindlimb suspended rat hindlimb muscles. Am J Phys Med Rehabil, 88(9):719-26.
Brocherie F, Babault N, Cometti G, Maffiuletti N, Chatard JC. (2005). Electrostimulation
training effects on the physical performance of ice hockey players. Med Sci Sports
Exerc, 37(3):455-60.
Brown JM, Henriksson J, Salmons S. (1989). Restoration of fast muscle characteristics
following cessation of chronic stimulation: physiological, histochemical and metabolic
changes during slow to fast transformation. Proc Royal Soc London B, 235:321-346.
Burkett LN, Phillips WT, Alvar B, Bartelt L, Stone W. (1998). The effect of electrical
stimulation combined with dynamic strength training on healthy individuals. Isokinetics
& Exercise Science, Vol. 7 Issue 3, p101-106p.
Caggiano E, Emrey T, Shirley S, Craik RL. (1994). Effects of electrical stimulation on
voluntary contraction for strengthening the quadriceps femoris muscles in an aged male
population. J Orthop Sports Phys Ther, 20(1):22-28
Callaghan MJ. (2002). Electrical Stimulation of The Quadriceps Muscle Group in Patients
with Patellofemoral Pain Syndrome. Centre for Rehabilitation Science, University of
Manchester PhD thesis, England.
Changsheng Sun, Yezhi Hu, Gui Tian. (2002). F-t curve measurement and neuromuscular
electrical stimulation in improving rower's performance. Medicine & Science in Sports
& Exercise, Volume 34(5) Supplement 1, p 16.
Cheing GL, Tsui AY, Lo SK, Hui-Chan CW. (2003). Optimal stimulation duration of tens in
the management of osteoarthritic knee pain. J Rehabil Med, 35: 62–68.
Chilibeck PD, Bell G, Jeon J, Weiss CB, Murdoch G, MacLean I, Ryan E, Burnham R.
(1999). Functional electrical stimulation exercise increases GLUT-1 and GLUT-4 in
paralyzed skeletal muscle. Metabolism, 48: 1409–1413.
Convery A, Racer B, Rohland R, Shannon J, Sorg J. (1994). The effects of electrical
stimulation and electromyographic biofeedback on muscle performance output with
training of the quadriceps muscle. Isokin Exer Sci, 4(3):122-127.
Currier DP, Petrilli CR, Threlkeld AJ. (1986). Effect of graded electrical stimulation on
blood flow to healthy muscle. Phys Ther, 66: 937-43.
De Luca CJ. (1997). The use of surface electromyography in biomechanics. J Appl
Biomech, 13:135-163.
Dehail P, Duclos C, Barat M. (2008). Electrical stimulation and muscle strengthening. Ann
Readapt Med Phys, 51(6):441-51. Epub.
Denier van der Gon JJ, Ter Haar Romeny BM, van Zuylen EJ. (1985). Behavior of motor
units of human arm muscles: Differences between slow isometric contraction and
relaxation. Journal of Physiology, 359:107-118.
Dervisevic E, Bilban M, Valencic V. (2002). The influence of low-frequency
electrostimulation and isokinetic training on the maximal strength of m. quadriceps
femoris. Isokinetics and Exercise Science, Volume 10, Number 4, pp 203 – 209.
Draper V, Ballard L. (1991). Electrical stimulation versus electromyographic biofeedback in
the recovery of quadriceps femoris muscle following anterior cruciate surgery. Phys
729
Ther, 71(6):455-464.
Dudley GA, Castro MJ, Rogers S, Apple DF Jr. (1999). A simple means of increasing
muscle size after spinal cord injury: a pilot study. Eur J Appl Physiol Occup Physiol,
80:394 –396.
Egginton S, Hudlicka O. (2000). Selective long-term electrical stimulation of fast glycolytic
fibres increases capillary supply but not oxidative enzyme activity in rat skeletal
muscles. Exp Physiol, 85;567-573.
Feiereisen P, Duchateau J, Hainaut K. (1997). Motor unit recruitment order during voluntary
and electrically induced contractions in the tibialis anterior. Exp Brain Res, 114: 117–23.
Filipovic A, Kleinöder H, Dörmann U, Mester J. (2011) Electromyostimulation--a
systematic review of the influence of training regimens and stimulation parameters on
effectiveness in electromyostimulation training of selected strength parameters. J
Strength Cond Res. 25(11):3218-38.
Filipovic, A., Kleinöder, H., Dörmann, U., & Mester, J. (2012). Electromyostimulation—a
systematic review of the effects of different electromyostimulation methods on selected
strength parameters in trained and elite athletes. The Journal of Strength & Conditioning
Research, 26(9), 2600-2614.
Forrester BJ, Petrofsky JS. (2004). Effect of electrode size, shape, and placement during
electrical stimulation. The Journal of Applied Research, Vol. 4, No. 2.
Gollnick PD, Karlsson J, Piehl K, and Saltin B. (1974). Selective glycogen depletion in
skeletal muscle fibers of man following sustained contractions. J Physiol, 241: 59–67.
Gondin J, Duclay J, Martin A. (2006a). Soleus- and gastrocnemii-evoked V-wave responses
increase after neuromuscular electrical stimulation training. J Neurophysiol,
Jun;95(6):3328-35. Epub, Feb 15.
Gondin J, Duclay J, Martin A. (2006b). Neural drive preservation after detraining following
neuromuscular electrical stimulation training. Neurosci Lett, 6;409(3):210-4.
Gondin J, Guette M, Ballay Y, Martin A. (2005). Electromyostimulation training effects on
neural drive and muscle architecture. Med Sci Sports Exerc, 37(8): 1291-9.
Gondin J, Guette M, Jubeau M, Ballay Y, Martin A. (2006). Central and peripheral
contributions to fatigue after electrostimulation training. Med. Sci. Sports Exerc, 38 (6):
1147-56.
Gregory CM, and Bickel CS. (2005). Recruitment patterns in human skeletal muscle during
electrical stimulation. Physical Therapy, Volume 85. Number 4.
Halbach WJ, Straus D. (1980). Comparison of electro-myo stimulation to isokinetic training
in increasing power of the knee extensor mechanism. J Orthop Sports Phys Ther,
2(1):20-24.
Hamada T, Hayashi T, Kimura T, Nakao K, and Moritani T. (2004). Electrical stimulation
of human lower extremities enhances energy consumption, carbohydrate oxidation, and
whole body glucose uptake. J Appl Physiol, 96 (3): 911-916.
Harris BA. (2005). The influence of endurance and resistance exercise on muscle
capillarization in the elderly: A review. Acta Physiol. Scand, 185 (2): 89–97.
Hartsell HD. (1986). Electrical muscle stimulation and isometric exercise effects on selected
quadriceps parameters. J Orthop Sports Phys Ther, 8(4):203-9.
Herrero JA, Izquierdo M, Maffiuletti NA, Garcia-Lopez J. (2006). Electromyostimulation
and plyometric training effects on jumping and sprint time. Int J Sports Med, 27:533–9.
Herrero AJ, Martín J, Martín T, Abadía O, Fernández B, García-López D., Herrero AJ,
Martin T, Abadia O, Fernandez B, Garcia (2010a) Short-term effect of strength training
with and without superimposed electrical stimulation on muscle strength and anaerobic
performance. A randomized controlled trial. Part I. J Strength Cond Res. Jun; 24(6):
730
1609-15.
Herrero AJ, Martín J, Martín T, Abadía O, Fernández B, García-López D. (2010b), Short-
term effect of plyometrics and strength training with and without superimposed electrical
stimulation on muscle strength and anaerobic performance: A randomized controlled
trial. Part II. J Strength Cond Res. 24: 1616-1622
Holcomb WR. (2006). Effect of training with neuromuscular electrical stimulation on elbow
flexion strength. Journal of sports science and medicine, 5, 276 – 281.
Hortobágyi T. (1996) Electrical muscle stimulation. Encyclopedia of Sports Medicine and
Science, [e-journal], Available at: http://www.sportsci.org/encyc, Last updated 12 Oct
2009 (accessed: 05/12/2010)
Hortobágyi T, Scott K, Lambert J, Hamilton G, Tracy J. (1999). Cross-education of muscle
strength is greater with stimulated than voluntary contractions. Motor Control, 3:205–
219.
Hudlicka O. (1982). Growth of capillaries in skeletal and cardiac muscle. Circ. Res, 50;451-
461.
Hultman E, and Spriet LL. (1986). Skeletal muscle metabolism, contraction force and
glycogen utilization during prolonged electrical stimulation in humans. J Physiol, 374:
493-501.
Hultman E. (1995). Fuel selection, muscle fibre, Proceedings of the Nutrition Sociey,
54,107-121.
Ito T, Tagawa Y, Shiba N, Tanaka S, Umezu Y, Yamamoto T, Basford JR. (2004).
Development of practical and effective hybrid exercise for use in weightless
environment. Conf Proc IEEE Eng Med Biol Soc, 6:4252-5.
Iwasaki T, Shiba N, Matsuse H, Nago T, Umezu Y, Tagawa Y, Nagata K, Basford JR.
(2006). Improvement in knee extension strength through training by means of combined
electrical stimulation and voluntary muscle contraction. Tohoku J Exp Med, 209(1):33-
40.
Johnston Brian D., (2004). ElectroMyoStimulation, Synergy, [e-journal], Available at:
http://www.trimform.no/electromyo.pdf (accessed: 20/02/2009)
Jubeau M, Zory R, Gondin J, Martin A, Maffiuletti NA. (2006). Late neural adaptations to
electrostimulation resistance training of the plantar flexor muscles, Eur J Appl Physiol,
98 (2): 202-11.
Kantor G, Alon G, Ho HS. (1994). The effects of selected stimulus waveforms on pulse and
phase characteristics at sensory and motor thresholds. Phys Ther, 74(10):951-62.
Kesar T, Binder-Macleod S. (2006). Effect of frequency and pulse duration on human
muscle fatigue during repetitive electrical stimulation. Exp Physiol, 91(6):967-76.
Kim CK, Strange S, Bangsbo J, Saltin B. (1995). Skeletal muscle perfusion in electrically
induced dynamic exercise in humans. Acta Physiol Scand, 153(3):279-87.
Kit-Ian PCK. (1991). Contemporary trends in electrical stimulation: The frequency-
specificity theory. Hong Kong Physiother. J, 13: 23 – 27.
Komi PV, Strength and power training for sports, Encyclopaedia of Sports Medicine: An
IOC Medical Commission Publication, 2nd Edition, Volume III, ed Komi P.V.,
Blackwell Science, 2003
Kubiak RJ, Whitman KM, Johnston RM. (1987). Changes in quadriceps femoris muscle
strength using isometric exercise versus electrical stimulation. J Orthop Sports Phys
Ther, 8(11):537-541.
Lai SL, De Dominico G, Strauss GR. (1988). The effect of different electro-motor
stimulation training intensities on strength improvement. Austr J Physiother, 3:151-164.
Lake DA. (1992). Neuromuscular electrical stimulation: An overview and its application in
731
the treatment of sports injuries. Sports Med, 13(5):320-336.
Laufer Y, Ries JD, Leininger PM, Alon G. (2001). Quadriceps femoris muscle torques and
fatigue generated by neuromuscular electrical stimulation with three different
waveforms. Phys Ther, 81:1307–1316.
Laughman RK, Youdas JW, Garrett TR, Chao EY. (1983). Strength changes in the normal
quadriceps femoris as a result of electrical stimulation. Phys Ther, 63(4):494-499.
Lewek M, Stevens J, Snyder-Mackler L. (2001). The use of electrical stimulation to increase
quadriceps femoris muscle force in an elderly patient following a total knee arthroplasty.
Phys Ther, 81:1565–1571.
Lieber RL, Kelly MJ. (1993). Torque history of electrically stimulated human quadriceps:
Implications for stimulation therapy. J Orthop Res, 11(1):131-141.
Lloyd T, DeDomencio G, Strauss GR, Singer K. (1986). A review of the use of electromotor
stimulation in human muscles. The Australian Journal of Physiotherapy, Vol. 32, No. 1.
Lopez-Guajardo A, Sutherland H, Jarvis JC, Salmons S. (2001). Induction of a fatigue
resistant phenotype in rabbit fast muscle by small daily amounts of stimulation. J Appl
Physiol, 90:1909-1918.
Maffiuletti NA, Cometti G, Amiridis IG, Martin A, Pousson M, Chatard JC. (2000). The
effects of electromyostimulation training and basketball practice on muscle strength and
jumping ability. Int J Sports Med, 21(6): 437-43.
Maffiuletti NA, Dugnani S, Folz M, Di Pierno E, Mauro F. (2002). Effect of combined
electrostimulation and plyometric training on vertical jump height. Med Sci Sports
Exerc, 34(10):1638-44.
Maffiuletti NA, Minetto MA, Farina D, Bottinelli R (2011). Electrical stimulation for
neuromuscular testing and training: State-of-the art and unresolved issues. European
Journal of Applied Physiology 111 (10): 2391–2397
Maffiuletti NA, Pesini M, Martin A. (2002). Activation on human plantar flexor muscles
increases after electromyostimulation training, J Apply Physiol, 92: 1383-1392.
Maffiuletti NA, Pensini M, Scaqlioni G, Ferri A, Ballay Y, Martin A. (2003). Effect of
electromyostimulation training on soleus and gastrocnemii H- and T-reflex properties.
Eur J Appl Physiol, 90(5-6):601-7.
Maffiuletti NA, Zory R, Miotti D, Pellegrino MA, Jubeau M, Bottinelli R. (2006).
Neuromuscular adaptations to electrostimulation resistance training. Am J Phys Med
Rehabil, 85(2):167-75.
Malatesta D, Cattaneo F, Dugnani S, Maffiuletti NA. (2003). Effects of
electromyostimulation training and volleyball practice on jumping ability. J. Strength
Cond. Res, 17:573–579.
Matsunaga T, Shimada Y, Sato K. (1999). Muscle fatigue from intermittent stimulation with
low and high frequency electrical pulses. Arch Phys Med Rehabil, 80:48-53.
Matsuse H, Shiba N, Umezu Y, Nago T, Tagawa Y, Kakuma T, Nagata K, Basford JR.
(2006). Muscle training by means of combined electrical stimulation and volitional
contraction. Aviat Space Environ Med, 77(6):581-5.
Mohr T, Carlson B, Sultentic C, Landry R. (1985). Comparison of isometric exercise and
high volt galvanic stimulation on quadriceps femoris muscle strength. Phys Ther,
65(5):606-612.
Mohr T, Dela F, Handberg A, Biering-Sorensen F, Galbo H, Kjaer M. (2001). Insulin action
and long-term electrically induced training in individuals with spinal cord injuries. Med
Sci Sports Exerc, 33: 1247–1252.
Nardone A, Romanò C, Schieppati M. (1989). Selective recruitment of high-threshold
human motor units during voluntary isotonic lengthening of active muscles. Journal of
732
Physiology, 409:451-471.
Nobbs LA, Rhodes EC. (1986). The effect of electrical stimulation and isokinetic exercise
on muscular power of the quadriceps femoris. J Orthop Sports Phys Ther, 8(5):260.
Nuhr M, Crevenna R, Gohlsch B, Bittner C, Fialka-Moser V, Quittan M, Pette D. (2003).
Functional and biochemical properties of chronically stimulated human skeletal muscle.
Eur J Appl Physiol, 89: 202–208.
Obajuluwa VA. (1991). Effect of electrical stimulation for 10 weeks on quadriceps femoris
muscle strength and thigh circumference in healthy young men. Physiother Theory Pract,
7(3):191-197.
Paavo VK. (2003). Strength and Power in Sport: Use of Electrical Stimulation in Strength
and Power Training. 2nd ed, Blackwell Publishing, Chapter 22, p. 426.
Paillard T, Noe F, Edeline O. (2005). Neuromuscular effects of superimposed and combined
transcutaneous electrical stimulation with voluntary activity: a review. Ann Readapt
Med Phys, 48:126–37.
Paillard T, Noe F, Passelergue P, Dupui P. (2005). Electrical stimulation superimposed onto
voluntary muscular contraction. Sports Med, 35(11):951-66.
Parker MG, Bennett MJ, Hieb MA, Hollar AC, Roe AA. (2003). Strength response in
human femoris muscle during 2 neuromuscular electrical stimulation programs. J.
Orthop Sports Phys. Ther, 33 (12). 719-26.
Perez M, Lucia A, Rivero JL, Serrano AL, Calbet JA, Delgado MA, Chicharro JL. (2002).
Effects of transcutaneous short term electrical stimulation on M.vastus lateralis
characteristics of healthy young men. Pflugers Archiv-European Journal of Physiology,
443(5):866-874.
Perez M, Lucia A, Santalla A, Chicharro JL. (2003). Effects of electrical stimulation on
VO2 kinetics and delta efficiency in healthy young men. Br J Sports Med, 37(2):140-3.
Petrofsky JS. (2004). Electrical Stimulation: Neurophysiological Basis and Application.
Basic Appl Myol, 14(4): 205-213.
Pette D. (2001). Plasticity in skeletal, cardiac and smooth muscle. Historical perspectives:
Plasticity of mammalian skeletal muscle. J Appl Physiol, 90:1119-1124.
Pichon F, Chatard JC, Martin A, Cometti G. (1995). Electrical stimulation and swimming
performance. Med Sci Sports Exerc, 27(12):1671-6.
Porcari JP, McLean KP, Foster C, Kernozek T, Crenshaw B, Swenson C. (2002). Effects of
electrical muscle stimulation on body composition, muscle strength, and physical
appearance. J Strength Cond Res, Vol. 16(2), pp. 165-172.
Raymond CH. So, Joseph K-F. Ng, Gabriel YF. Ng. (2007). Effect of transcutaneous
electrical acupoint stimulation on fatigue recovery of the quadriceps, Eur J Appl Physiol,
100(6):693-700.
Requena SB, Padial PP, Gonzalez-Badillo JJ. (2005). Percutaneous electrical stimulation in
strength training: An update. J Strength Cond Res,19:438–48.
Robinson AJ, Snyder-Mackler L. (2007). Clinical Electrophysiology: Electrotherapy and
Electrophysiologic Testing. 3th ed, Wolters Kluwer-Lippincott, Williams&Wilkins.p.
109, 213, 217, 218.
Roy D, Johannsson E, Bonen A, and Marette A. (1997). Electrical stimulation induces fiber
type-specific translocation of GLUT-4 to T tubules in skeletal muscle. Am J Physiol
Endocrinol Metab, 273: E688–E694.
Salmons S, Hendricksson J. (1981). The adaptive response of skeletal muscle to increased
use. Muscle Nerve, 4:94-105.
Shenkman BS, Lyubaeva EV, Popov DV, Netreba AI, Bravy YR, Tarakin PP, Lemesheva
YS, Vinogradova OL. (2007). Chronic effects of low-frequency low-intensity electrical
733
stimulation of stretched human muscle. Acta Astronautica, 60, 505 – 511.
Singer KP. (1986). The influence of unilateral electrical muscle stimulation on motor unit
activity patterns in atrophic human quadriceps. Aust. J. Physiother, 32:31–37.
Sinacore DR, Delitto A, King DS, Rose SJ. (1990). Type II fiber activation with electrical
stimulation: A preliminary report. Phys Ther 70: 416–422.
Smith GV, Alon G, Roys SR, Gullapalli RP. (2003). Functional MRI determination of a
dose-response relationship to lower extremity neuromuscular electrical stimulation in
healthy subjects. Exp Brain Res, 150:33–9.
Snyder-Mackler L, Delitto A, Bailey SL, Stralka SW. (1995). Strength of the quadriceps
femoris muscle and functional recovery after reconstruction of the anterior cruciate
ligament. J Bone Joint Surg (Am), 77(A) (8):1166-1173.
Snyder-Mackler L, Ladin Z, Schepsis AA, Young JC. (1991). Electrical stimulation of the
thigh muscles after reconstruction of the anterior cruciate ligament. J Bone Joint Surg
(Am), 73(A)(7):1025-1036.
Soo CL, Currier DP, Threkeld AJ. (1988). Augmenting voluntary torque of healthy muscle
by optimisation of e lectrical stimulation. Phys Ther, 68(3):333-337.
Starkey, C. (2013). Therapeutic modalities: FA Davis, p.249-252.
Stevenson SW, Dudley GA. (2001). Dietary creatine supplementation and muscular
adaptation to resistive overload. Med Sci Sports Exerc, 33: 1304–1310.
Thériault R, Boulay MR, Thériault G, Simoneau J. (1996). Electrical stimulation-induced
changes in performance and fiber type proportion of human knee extensor muscles. Eur J
Appl Physiol Occup Physiol, 74(4), 311 – 317.
Theurel J, Lepers R, Pardon L, Maffiuletti NA. (2007). Differences in cardiorespiratory and
neuromuscular responses between voluntary and stimulated contractions of the
quadriceps femoris muscle. Respiratory Physiology & Neurobiology, 157, 341–347.
Trimble MH, Enoka RM. (1991). Mechanisms underlying the training effects associated
with neuromuscular electrical stimulation. Phys Ther, 71(4):273-282.
Vanderthommen M, Depresseux JC, Bauvir P, Degueldre C, Delfiore G, Peters JM, Sluse F,
Crielaard JM. (1997). A positron emission tomography study of voluntarily and
electrically contracted human quadriceps. Muscle Nerve, 20:505-7.
Vanderthommen M, Duchateau J. (2007). Electrical stimulation as a modality to improve
performance of the neuromuscular system. Exerc Sport Sci Rev, 35:180–5.
Vanderthommen M, Duteil S, Wary C, Raynaud JS, Leroy-Willig A, Crielaard JM, Carlier
PG. (2003). A comparison of voluntary and electrically induced contractions by
interleaved 1H- and 31 P-NMRS in humans. J Appl Physiol, 94: 1012–1024.
Vinge O, Edvardsen L, Jensen F, Jensen FG, Wernerman J, Kehlet H. (1996). Effect of
transcutaneous electrical muscle stimulation on post operative muscle mass and protein
synthesis. Br J Surg, 83:360-363.
Walker DC, Currier DP, Threlkeld AJ. (1988). Effects of high voltage pulsed electrical
stimulation on blood flow. Phys Ther, 68: 481-5
Ward AR, Shkuratova N. (2002). Russian electrical stimulation: the early experiments. Phys
Ther, 82:1019-1030.
Wu H, Naya FJ, McKinsey TA, Mercer B, Shelton JM, Chin ER, Simard AR, Michel RN,
Bassel-Duby R, Olson EN, Williams RS. (2000). MEF2 responds to multiple calcium-
regulated signals in the control of skeletal muscle fiber type. EMBO J, 19:1963–73.
... A 12 hetes NANO tréning után szignifikánsan nőtt a hamstring izomzat maximális izometrikus erőkifejtése (93,45±27,81 vs. 123,98±46,75 N; p= 0,006) és a funkcionális H/Q ráta (0,68±0,15 vs. Electromyostimulation (EMS) has been used in medicine for rehabilitation and recovery for several decades (Jee, 2018;Kemmler et al, 2016, Takeda et al, 2017, but also in training for sports and fitness to increase muscle force (Kaya and Erzeybek, 2016). The theory behind it is that using weak, high-frequency electrical impulses, the muscles can be activated with higher frequency than that of their natural activation by the nervous system. ...
Article
Full-text available
Kiválasztási kritériumok vizsgálata utánpótláskorú evezős leányok és fiúk körében Examination of selection criteria among young rowing male and female Összefoglaló Tanulmányunk célja volt az evezősök élettani változóit és a teljesítmény összetevőit vizsgálni 2000 m-es távon. A vizsgálatba 10 magyar város, 16 evezős klubjából kétszáznegyvenöt sportolót (N=245), 17,24±1,38 éves leányt (nl =101); és 18,22±1,33 év átlagéletkorú fiút (nf =144) vontunk be. Az antropometriai adatfelvételt hitelesített, Sieber-Hegner gyártmányú mérőeszközökkel végeztük. Munkánk során a Nemzetközi Biológiai Program Weiner és Lourie, (1969) eljárási javaslatait tekintettük iránymutatónak. Testtömeget (TS), testmagasságot (TM), ülőmagasságot (ÜM), karöltőt (KÖ) mértünk, valamint testtömeg-indexet (BMI) testfelszínt (BSA) számoltunk. Hitelesített evezősergométeren (Concept 2 D-modell) 3x100 m, 60 sec, 500 m, 2000 m és 6000 m távon mértük a leadott teljesítményt wattban (W). A becsült relatív aerob kapacitást (b.r.VO2) a 2000 m-en leadott teljesítmény (watt), életkor, nem, testtömeg és edzettségi szintet figyelembe véve, McArdle és munkatársai (2006), tapasztalati képlete alapján határoztuk meg, valamint relatív teljesítményt (rW2k×kg-1) számoltunk. A lineáris regressziós elemzés bebizonyította, hogy a legjobb teljesítmény-előrejelző a becsült relatív aerob kapacitás (e.r.VO2max). A tanulmány hozzájárul az evezés tudományos alapjainak a megértéséhez, az élettani változók és teljesítmény kapcsolata értékes lehet az edzésprogramok tervezésénél, illetve a csapat kiválasztása során. Kulcsszavak: antropometria, teljesítményösszetevők, keringési rendszer Abstract The aim of this study was to examine the relationship between selected physiological variables of male and female rowers and rowing performance as determined by a 2000 m time-trial. The participants were 245 young rowers’ athletes: female (nf=101) and male (nm=144) club standard oarsmen. Their mean age was 17.24±1.38 years in females and 18.22±1.33 years in males. In accordance with the recommendations of the The International Society for the Advancement of Kinanthropometry, the anthropometry was performed as follows: stature (BH), body mass (BM), arm span (AS), sitting height (SH), calculated body mass index (BMI), and body surface area (BSA). The participants were tested on the rowing ergometer to estimated their relative maximal oxygen uptake (e.r.VO2max) based on McArdle et al. (2006) equation and calculated the relative performance (rW2k×kg-1). A repeated-measures analysis of variance showed significant differences between estimated maximal oxygen uptake in each age groups independent of gender. A stepwise multiple regression showed that the e.r.VO2max was the best single predictor of the completed time for the 2000 m time-trial. This study has contributed to the scientific understanding of rowing, limited information is available on the relationship between physiological variables of rowers and rowing performance. Relating physiological variables to performance could be valuable for designing training programs and for team selection. Keywords: anthropometry, performance components, circulatory system
Article
The aim of this study was to examine the effects of Electrical Muscle Stimulation (EMS) training and traditional fitness training practices on anthropometric and strength values on sedentary women. 20 sedentary women (age 25.40 ± 1.10) living in Osmaniye province participated in the study voluntarily. Participants were divided into two groups as EMS and fitness training group. The normality distribution of the data was examined with Shapiro-Wilk test. Since the data showed a normal distribution, the dependent groups T test was used for the pre-test and post-test anthropometric and strength comparisons of the trainings applied for 6 weeks. There was no statistically significant difference between the pretest-posttest values of the EMS and fitness groups according to the anthropometric variables (body weight, body mass index, fat percentage values and lean body mass) (p>0.05). In circumference measurements, no statistically significant difference was found in the pre-test and post-test values of the EMS training group (p>0.05). While there was a significant difference in biceps and biceps circumference measurements in the fitness training group, there was no significant difference in the abdominal, hip and chest circumferences as in the EMS group. As a result of the study, significant differences were found in the strength pretest-posttest values of the EMS and Fitness groups. As a result, strength gain was achieved in sedentary women as a result of EMS training and traditional fitness training. Based on this finding, new technology EMS training, which is easy to apply and in a short time, with less risk of injury, is recommended in addition to traditional fitness training.
Article
Full-text available
Requena Sanchez, B., P. Padial Puche, and J.J. Gonzdlez-Badillo. Percutaneous electrical stimulation in strength training: an update. J Strength Cond. Res. 19(2):438-448. 2005.-Numerous studies have used percutaneous electrical stimulation (PES) in the context of training programs to develop strength and physical performance in healthy populations (sedentary or trained). Significant increases in muscle and fiber cross-sectional area, isokinetic peak torque, maximal isometric and dynamic strength, and motor performance skills have been found after PES training. These strength gains are explained on the basis of the characteristics of PES motor units (MUs) recruitment: (a) a continuous and exhausting contractile activity in the same pool of MUs during the entire exercise period, (b) a supramaximal temporal recruitment imposed by the high frequency chosen (up to 40 Hz), and (c) a synchronous recruitment of neighboring fibers. The PES training method is complementary to voluntary training, mainly because the application of PES causes an unconventional spatial recruitment of MUs that, depending on the muscular topography, may entail the preferential recruitment of the fast-twitch MUs. In addition, the method does not specifically develop elasticity in skeletal muscle, and it must be accompanied by a technical workout.
Article
This lecture explores the various uses of surface electromyography in the field of biomechanics. Three groups of applications are considered: those involving the activation timing of muscles, the force/EMG signal relationship, and the use of the EMG signal as a fatigue index. Technical considerations for recording the EMG signal with maximal fidelity are reviewed, and a compendium of all known factors that affect the information contained in the EMG signal is presented. Questions are posed to guide the practitioner in the proper use of surface electromyography. Sixteen recommendations are made regarding the proper detection, analysis, and interpretation of the EMG signal and measured force. Sixteen outstanding problems that present the greatest challenges to the advancement of surface electromyography are put forward for consideration. Finally, a plea is made for arriving at an international agreement on procedures commonly used in electromyography and biomechanics.
Article
The purpose of this study was to examine muscle performance output as effected by electrical stimulation with and without eledromyographic (EMG) biofeedback in conjunction with quadriceps femoris muscle (QFM) strengthening exercises. Six males and six females aged from 20 to 36 participated in this study. Subjects were assigned to one of three independent groups. One group (n = 4) performed maximal volitional isometric contractions (MVICs) of the QFM and served as the control; the second group (n = 4) underwent strength training augmentation concurrent with electrical stimulation; the third group (n = 4) received EMG biofeedback-triggered electrical stimulation (BTES), i.e., electrical stimulation based on EMG biofeedback from volitional isometric contractions. Each group underwent pretesting and posttesting to record MVICs. The groups trained 3 days a week for 6 weeks. All groups had an increase in peak torque production over the 6-week training period, with the EMG-BTES group showing the greatest increase from pretest to posttest. Results of this study give preliminary evidence of the usefulness of electrical stimulation, especially when triggered by an EMG biofeedback signal, in strength training.
Article
Since the early 1960's interest has risen for using electrical stimulation (ES) as a supplement to voluntary effort in strength training programs. The purpose of this study was to evaluate the effectiveness of ES combined with simultaneous maximum dynamic contraction. An experimental, randomized control group was used. The independent variables were three methods of training, (a) isotonic weight training, (b) isokinetic resistance, and (c) isokinetic with ES. The dependent variables measured were, (a) peak torque at 36°/sec, (b) height in the vertical jump, and (c) time in the 50-yard sprint. Results were analyzed using a 3 x 6 split-plot design. No significant differences were found among groups for the design (F2,12 = 1.045, P > 0.3816). It was concluded that in groups of healthy individuals, ES combined with dynamic contraction in a training program does not develop strength and/or functional capacity more effectively than isokinetic or isotonic contractions without ES.
Article
The objective of this study was to examine the influence of isokinetic training and low-frequency electrostimulation in three groups of male athletes (N = 20, each group). Three different training methods have been compared: isokinetic training (IT) alone, training with low-frequency electrostimulation (LEFS), and the combination of the two methods. Maximal muscle power was measured before and at the end of the training programs, using a REV 9000 isokinetic dynamometer. The findings indicate that all training methods result in significant increase in muscle strength. However, the largest training effect was due to the combination of IT and LFES.
Article
A clinical study of six individuals was set up to compare an Electro-Myo stimulation protocol to an isokinetic protocol. The objective of the study was to see which was more effective in increasing power in the knee extensor mechanism. Results of the study showed that isokinetics were superior to Electro-Myo stimulation in increasing power. One question that remained unanswered in the testing was whether a higher faradic current, if tolerated, would be more efficient in increasing the power of a muscle group than would isokinetics.
Article
The purpose of this study was to compare the power and strength changes, of the quadriceps femoris muscle group, following 6 weeks of training. Twenty-seven moderately trained, female subjects were placed into three equated groups: electrical stimulation plus isokinetic exercise (ES + IE), isokinetic exercise (IE), and electrical stimulation (ES). A Cybex® II isokinetic dynamometer was used for testing the quadriceps' power and strength output at the velocities of 0, 30, 100, and 180°/sec. The ES + IE and ES groups received faradic stimulation (progressive from 10–20 mA) from a Multitone Multifaradic Unit (model F283, Multitone Electric Co., London, England). In addition, the ES + IE group performed isokinetic contractions concurrently with the faradic stimulation. Thigh circumference (TC) and time to peak tension (TPT) were also calculated during the pre-, mid-, and post-tests. Results indicated that a significant power increment was evident between the pre- and post-tests and the pre- and mid-tests for ...
Article
We made an experiment on electrical stimulation to the intercostal muscles in human patients with scoliosis. The results were analyzed after about nine months. In many cases, flexibility of the scoliotic curve increased. And the increased flexibility of curvature may increase the effect of brace correction.