Content uploaded by Amir Hoshang Bakhtiary
Author content
All content in this area was uploaded by Amir Hoshang Bakhtiary on Dec 20, 2013
Content may be subject to copyright.
ORIGINAL ARTICLE
Influence of vibration on delayed onset of muscle soreness
following eccentric exercise
Amir H Bakhtiary, Ziaeddin Safavi-Farokhi, Atefeh Aminian-Far
...................................................................................................................................
See end of article for
authors’ affiliations
........................
Correspondence to:
Amir H Bakhtiary,
Physiotherapy Department,
Rehabilitation Faculty,
Semnan University of
Medical Sciences, Km 5
Road to Damghan, Semnan,
Iran; amir822@yahoo.com
Received20 September2006
Revised 20 September 2006
Accepted 8 November 2006
Published Online First
29 November 2006
........................
Br J Sports Med 2007;41:145–148. doi: 10.1136/bjsm.2006.031278
Delayed onset muscle soreness (DOMS), which may occur after eccentric exercise, may cause some reduction
in ability in sport activities. For this reason, several studies have been designed on preventing and controlling
DOMS. As vibration training (VT) may improve muscle performance, we designed this study to investigate the
effect of VT on controlling and preventing DOMS after eccentric exercise.
Methods: Fifty healthy non-athletic volunteers were assigned randomly into two experimental, VT (n = 25) and
non-VT (n = 25) groups. A vibrator was used to apply 50 Hz vibration on the left and right quadriceps,
hamstring and calf muscles for 1 min in the VT group, while no vibration was applied in the non-VT group.
Then, both groups walked downhill on a 10
˚
declined treadmill at a speed of 4 km/hour. The measurements
included the isometric maximum voluntary contraction force (IMVC) of left and right quadriceps muscles,
pressure pain threshold (PPT) 5, 10 and 15 cm above the patella and mid-line of the calf muscles of both
lower limbs before and the day after treadmill walking. After 24 hours, the serum levels of creatine-kinase
(CK), and DOMS level by visual analogue scale were measured.
Results: The results showed decreased IMVC force (P = 0.006), reduced PPT (P = 0.0001) and significantly
increased mean of DOMS and CK levels in the non-VT group, compared to the VT group (P = 0.001).
Conclusion: A comparison by experimental groups indicates that VT before eccentric exercise may prevent
and control DOMS. Further studies should be undertaken to ascertain the stability and effectiveness of VT in
athletics.
T
he first detailed description of delayed onset muscle soreness
(DOMS) was given by Hough in 1902.
1
DOMS is often
precipitated predominantly by eccentric exercise, such as
downhill running, plyometrics and resistance training. It has been
explained
23
that the injury itself is a result of eccentric exercise
causing damage to the muscle cell membrane, which sets off an
inflammatory response. In other words, shocking the muscles
during the eccentric range of motion is probably the leading factor
in producing DOMS. It has been claimed that the type of force
development during eccentric exercise may cause sarcoma
disruption and consequently an inflammatory response within
the muscle.
4–6
DOMS is typically experienced by all individuals
regardless of fitness level, and is a normal physiological response
to increased exertion and the introduction of unfamiliar physical
activities.
7
The pain and discomfort associated with DOMS
typically peaks 24–48 hours after an exercise bout, and resolves
within 96 hours.
8
Generally, an increased perception of soreness
occurs with greater intensity and a higher degree of unfamiliar
activities.
9
Other factors that play a role in DOMS are muscle
stiffness, contraction velocity, fatigue, and angle of contraction.
2
Due to the sensation of pain and discomfort, which can impair
physical training and performance, prevention and treatment of
DOMS is of great concern to coaches, trainers and therapists.
10
Although DOMS is experienced widely, science has not estab-
lished a sound and consistent treatment for it.
Recent research has shown that vibration training (VT) may
improve muscle performance.
11 12
By considering this mechan-
ism, we designed this study to find out if VT before eccentric
exercise may prevent DOMS by improving muscular strength
and power development strategy,
13–17
improving kinesthetic
awareness,
18
and providing insights into the effects of fati-
gue,
19 20
within the vibrated muscles.
MATERIALS AND METHODS
The study was approved by the ethical committee of Semnan
University of Medical Sciences. Fifty healthy non-athletic
volunteers (25 females, mean (SD) age 21.1 (0.2) years and
25 males mean (SD) age 20.1 (0.5) years) were assigned
randomly into two experimental, VT and non-VT groups.
Exclusion criteria included a history of cardiac and neuromus-
cular diseases, undertaking severe sport activity or having
received an intramuscular injection during the last week.
A computer generated randomisation list was drawn up by
the statistician for each group. It was given to the physiother-
apy department in sealed numbered envelopes. When the
subjects qualified to enter the study and had signed their
informed consent forms, the appropriate numbered envelope
was opened at the reception; the card inside indicated the
subject’s allocation to one of the VT or non-VT groups. This
information was then given to the physiotherapist to admin-
ister the appropriate intervention.
Intervention
Both experimental groups walked downhill on a 10
˚
declined
treadmill at a speed of 4 km per hour for 30 min. In the VT
group, a 50 Hz vibrator apparatus (model VR-7N, ITO, Tokyo,
Japan) was used to apply vibration on the middle line of each of
the left and right quadriceps, hamstring and calf muscles for 1
min before downhill treadmill walking, while the subjects in
the non-VT group did not receive any vibration before downhill
treadmill walking.
Measurements
Measurements were performed before and 24 h after treadmill
walking and included isometric maximum voluntary contrac-
tion. The IMVC force of the left and right quadriceps muscles in
100
˚
of knee flexion was measured in the sitting position. The
subject was asked to sit on a back-supported quadriceps table
and a load cell was connected to the distal end of her/his leg by
means of a tight sling. The output of the load cell was
connected to a digital monitor so it was possible to record and
save the maximum tension on the load cell. After bringing to
145
www.bjsportmed.com
zero the output of the load cell, the subject was encouraged to
perform IMVC by pulling the sling tight as hard as she/he could,
three times, with 30-second intervals between each pull. The
best attempt was recorded and considered as the quadriceps
IMVC force in newtons.
Pressure pain threshold (PPT) on the 5, 10 and 15 cm above
the left and right patellae and also on the middle line of calf
muscles was measured by a 20 ml syringe with a spring inside
which was scaled from 0 to 10. The rounded tip of syringe was
placed at the above points in a vertical position and the piston
was pressed down. The subject was asked to announce any
unpleasant sensation (pain), and then the indicating number
on the syringe was recorded as the PPT.
The level of muscle soreness was evaluated by mean of a
Visual Analogue Scale (VAS). The day after treadmill walking,
the subject was asked to indicate her/his feel of the level of
muscle soreness in each lower limb along a 10 cm line ranging
from 0 (‘‘no muscle soreness at all’’) to 10 (‘‘the most severe
muscle soreness that I can imagine).
The serum level of creatine kinase (CK) was measured
24 hours after treadmill walking by taking 3 cc blood samples
from the brachial artery in the front of the elbow and then the
level of CK enzyme was measured in the laboratory.
Statistics
To compare the possible effect of VT on DOMS, an intention to
treat analysis was used which involved all subjects who were
randomly assigned to their group. Student’s t tests were used to
compare the mean changes in the IMVC force, PPT values and
the mean of CK level and muscle soreness between the
experimental groups.
RESULTS
Fifty healthy subjects were randomly assigned into two
experimental VT (n = 25, 12 male and 13 female) and non-VT
(n = 25, 13 male and 12 female,) groups and the study was
then completed. The mean age was 20.6 (1.9) years (mean
(SD)) for the VT group, and 20.6 (2.1) years (mean (SD)) for
non-VT group, without any significant differences between the
two groups.
Isometric maximum voluntary contraction force
A comparison of the mean change in the IMVC force in the
right quadriceps showed a significantly higher decrease
(P = 0.001) in the non-VT group (239.6 (46.6) years, mean
(SD)) compared with the VT group (37.2 (100.1) years, mean
(SD)). This reduction was also seen in the left quadriceps (non-
VT group 216.5 (77.6) years vs VT group 56.8 (100.9) years,
P = 0.006), fig 1.
Pain pressure threshold
Table 1 shows the mean changes in PPT at 5, 10 and 15 cm
above the right and left patella. Comparison of these values
from non-VT and VT groups showed significant reduction of
PPT in the non-VT group (P = 0.0001). The same significant
reduction (P = 0.0001) of PPT was seen in the calf muscles of
the non-VT group (right 21.1 (1.3) and left 21.3 (1.4))
compared with the VT group (right 0.4 (0.8) and left 0.4 (1.2)).
Level of muscle soreness
The comparison of mean level of muscle soreness recorded the
day after treadmill walking showed higher soreness in the non-
VT group (right 2.3 (1.9) and left 2.3 (2.1)) vs VT group (right
0.4 (1.1) and left 0.5 (1.1)). These differences were significant
in both lower limbs (P = 0.0001), fig 2.
Level of CK enzyme
The higher mean of the CK enzyme was found in the non-VT
group (195.2 (109.2)) compared with the VT group (116.1
(27.8)) which was statistically significant (P = 0.001), fig 3.
Figure 1 Mean change of maximum isometric voluntary contraction force
of quadriceps.
Table 1 Mean changes in the pain pressure threshold of the right and left quadricepsat5,10
and 15 cm above the patella
5 cm above patella 10 cm above patella 15 cm above patella
Right
mean (SD)
Left
mean (SD)
Right
mean (SD)
Left
mean (SD)
Right
mean(SD)
Left
mean (SD)
VT group 0.3 (1.5) 0.4 (1.1) 0.5 (1.3) 0.1 (1.1) 0.5 (0.8) 0.3 (0.7)
Non-VT
group
21.8 (1.3) 21.6 (1.4) 21.3 (1.0) 21.2 (1.1) 21.3 (0.9) 21.1 (1.1)
p Value 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001
Figure 2 Mean change of delayed onset muscle soreness at 24 h after
eccentric exercises.
146 Bakhtiary, Safavi-Farokhi, Aminian-Far
www.bjsportmed.com
DISCUSSION
Delayed onset muscle soreness and reduced muscle strength
after eccentric exercise
521
may decrease functional activities in
athletics.
722
Because of this, different methods have been
investigated and recommended to prevent these symptoms.
2
This study was designed to find the possible effects of VT to
control and prevent DOMS after eccentric exercise.
A previous study showed muscle strength reduction after
eccentric activities,
9
while our findings showed no muscle
strength reduction in the IMVC force of quadriceps in the VT
group, which may be due to the establishment of optimum
neuromuscular function in the quadriceps muscles by applying
VT. This has been reported by other researchers,
12 15
who
showed better muscle performance after vibratory stimulation.
Thompson and Belanger (2002) also showed that VT may
increase muscle spindle activities and establish motor unit
activity synchronisation that may optimise neuromuscular
function.
23
By contrast, it has been shown that muscle spindle
stimulation by vibration may increase the afferent activities of
muscle spindles which may increase background tension in the
vibrated muscles.
24 25
This increased background tension and
motor unit activity synchronisation in the vibrated muscle may
prevent sarcoma disruption or damage to excitation–contrac-
tion coupling, which may happen due to tension development
during eccentric exercise.
4
Therefore, this optimised muscle
performance may control and prevent muscle damage and so
reduce DOMS. This reduction in DOMS was seen in our study,
as we found increased PPT in the right and left quadriceps and
calf muscles, lower muscle soreness, and lower levels of CK
enzyme in the VT group compared with the non-VT group.
The CK enzyme has been defined as an index for muscle
damage and its level will be increased within 24 to 48 hours
after eccentric activities,
522
which is a sign of eccentric muscle
damage. However this increase was seen only in the non-VT
group, and not in the VT group. In fact, the lower CK level in
the VT group may indicate lower muscle damage in this group,
while the non-VT group showed a higher CK level and so higher
muscle damage, which was accompanied by higher muscle
soreness.
These findings may indicate that vibration training before
eccentric exercise may help the muscles to build up a
background tension and optimal neuromuscular activity to
overcome the increased passive tension within the exercised
muscles during eccentric activities. Thus, vibration training
could be used before eccentric activities to control and prevent
delayed onset muscle soreness and it might be a useful method
for athletes to prevent any DOMS in their sports activities.
CONCLUSION
DOMS is a major complication faced by athletes after eccentric
activities, which may compel them to postpone their sports
activities, thus prevention and treatment of DOMS is of great
concern to coaches, trainers, and therapists. In this study, we
investigated the effect of vibration on muscle before downhill
treadmill walking and our results showed that applying
vibration before eccentric activities may prevent DOMS and
so it may help non-athletic people to follow and complete their
sport activities without any delay. Further studies are needed to
investigate these results to find the possible application in
athletics.
ACKNOWLEDGEMENTS
This study was supported financially by the Semnan University of
Medical Sciences. We thank the physiotherapists Miss Gafari and Ranj-
Keshande and all the people in the Rehabilitation Clinic of the Semnan
Rehabilitation Facility who help us complete this study.
Authors’ affiliations
.......................
Amir H Bakhtiary, Physiotherapy Department, Rehabilitation Faculty,
Semnan University of Medical Sciences, Km 5 Road to Damghan, Semnan,
Iran
Ziaeddin Safavi-Farokhi, Atefeh Aminian-Far, Rehabilitation Faculty,
Semnan University of Medical Sciences, Semnan, Iran
Competing interests: None declared
REFERENCES
1 Hough T. Ergographic studies in muscular soreness. Am J Physiol 1902;7:76–92.
2 Connolly DAJ, Sayers SP, McHugh MP. Treatment and prevention of delayed
onset muscle soreness. J Strength Cond Res 2003;17:197–8.
3 Dierking, Jenny K, Bemben, et al. Delayed Onset Muscle Soreness. Strength and
Conditioning 1998;20:44–50.
4 McHugh MP, Connolly J, Eston RG, et al. Exercise induced muscle damage
and potential mechanisms for the repeated bout effect. Sports Med
1999;27:158–70.
5 Nosaka K, Clarkson PM. Changes in indicators of inflammation after eccentric
Exercise of the elbow flexors. Med Sci Sports Exs 1996;28:953–61.
6 Nosaka K, Newton M. Repeated eccentric exercise bouts do not exacerbate
muscle damage and repair. J Strength Cond Res 2002;16:117–22.
7 Smith LL, Fulmer MG, Holbert MR, et al. The impact of a repeated bout of
eccentric exercise on muscular strength, muscle soreness and creatine kinase.
Br J Sports Med 1994;28:267–71.
8 Smith LL. Acute inflammation: The underlying mechanism in delayed onset muscle
soreness. Med Sci Sports Exerc 1991;23:542–51.
9 Cleak MJ, Eston RG. Muscle soreness, swelling, stiffness and strength loss after
intense eccentric exercise. Br J Sports Med 1992;26:267–72.
10 Szymanski DJ. Recommendations for the avoidance of delayed-onset muscle
soreness. J Strength Cond Res 2001;23:7–13.
11 Ivanenko YP, Grasso R, lacquaniti F. Influence of leg muscle vibrationon human
walking. J Neurophysiol 2000;84:1737–47.
12 Bosco C, Cardinal M, Tsarpela O. Influence of vibration on mechanical power
and electromyogram activity in human arm flexor muscles. Eur J Appl Physiol
1999;79:306–11.
Figure 3 Mean serum level of creatine kinase enzyme at 24 h after
eccentric exercise.
What is already known on this topic?
Delayed Onset Muscle Soreness (DOMS) is one of the
complications that has been most reported by athletes after
severe exercise. Several methods have been applied to prevent
DOMS but it is still a matter of recent study. By contrast,
vibration training (VT) has been used recently as a useful
method to increase muscle performance. By considering these
findings, we propose that applying VT before eccentric exercise
may improve muscle performance and thus prevent DOMS.
What this study adds?
Our findings show that VT may improve muscle performance
and thus prevent DOMS by prevention of sarcoma disruption,
which is caused by high tension development during eccentric
exercises.
Influence of vibration on delayed onset of muscle soreness following eccentric exercise 147
www.bjsportmed.com
13 Johnston RM, Bishop B, Coffey GH. Mechanical vibration of skeletal muscles.
Physical Therapy 1970;50:499–505.
14 Samuelson B, Jorfeldt L, Ahlborg B. Influence of vibration on endurance of
maximal isometric contraction. Clinical Physiology 1989;9:21–5.
15 Issurin VB, Liebermann DG, Tenenbaum G. Effect of vibratory stimulation
training on maximal force and flexibility. J Sports Sci 1994;12:561–6.
16 Issurin VB, Tenenbaum G. Acute and residual effects of vibratory
stimulation on explosive strength in elite and amateur athletes. J Sports Sci
1999;17:177–82.
17 Warman G, Humphries B, Purton J. The effects of timing and application of
vibration on muscular contractions. Aviat Space Environ Med
2002;73:119–27.
18 Burke JR, Schutten MC, Koceja DM, et al. Age-dependent effects of muscle
vibration and the Jendrassik maneuver on the patellar tendon reflex response.
Arch Phys Med Rehabil 1966;77:600–4.
19 Herzog W, Zhang Y, Vaz M, et al. Assessment of muscular fatigue using
vibromyography. Muscle and Nerve 1994;17:1156–61.
20 Gabriel DA, Basford JR, Kai-Nan A. Vibratory facilitation of strength in fatigued
muscle. Arch Phys Med Rehabil 2002;83:1202–5.
21 Allen DG. Eccentric muscle damage: Mechanisms of early reduction of force.
Acta Physiol Scand 2001;71:311–9.
22 Smith LL. Causes of delayed onset muscle soreness and the impact on athletic
performance: a review. J Appl Sport Sci Res 1992;6:135–41.
23 Thompson C, Belanger M. Effects of vibration in inline skating on the
Hoffmann reflex, force, and proprioception. Med Sci Sports Exerc
2002;34:2037–44.
24 Ren JC, Fan XL, Song XA, et al. Influence of 100 Hz sinusoidal vibration on
muscle spindle afferents of soleus muscles in suspended situation rat. Space Med
Eng 2004;17:340–4.
25 Shinohara M, Moritz CT, Pascoe MA, et al. Prolonged muscle vibration increases
stretch reflex amplitude, motor unit discharge rate, and force fluctuations in a
hand muscle. J Appl Physiol 2005;99:1835–42.
...............
COMMENTARY
...............
This study investigated the effect of vibration training on
preventing and controlling delayed onset of muscle soreness.
The author has measured the isometric force of knee extensor
muscles, pain threshold pressure, delayed onset of muscle
soreness (DOMS) level and creatine kinase enzyme to compare
two experimental and control groups. The results showed lower
values of isometric force and pain pressure threshold and
higher values of DOMS level and creatine kinase enzyme in a
non-vibration training group (control group). The authors
suggest that the use of vibration training before eccentric
exercise can prevent and control DOMS. The authors base their
study on the observation that in previous studies, the use of
vibration training would establish an optimum neuromuscular
function in the quadriceps muscle via muscle spindle stimula-
tion. They stated that this function of vibration may prevent
sarcoma disruptions of the muscle. In fact, this is the major
point of this study, by which one can prevent a major
complication of athletes after eccentric muscle contraction.
Asghar Rezasoltani
Shaheed Beheshti Medical University, Faculty of Rehabilitation, Tehran,
Islamic Republic of Iran; arezasoltani@yahoo.com
ECHO.......................................................................................................................
Cognition is best yardstick of fitness after concussion
Please visit the
British Journal
of Sports
Medicine
website [www.
bjsportmed.
com] for a link
to the full text
of this article.
C
oncussed athletes must wait until cognitive function returns to normal before resuming
their sport, researchers are urging, after prospectively comparing performance of
Australian rules footballers with and without symptoms days after their initial injury.
Waiting until symptoms resolve, as currently recommended, is not enough, they say.
Footballers showed significantly reduced performance in motor function and divided
attention on computerised tests if they still had even minimal symptoms at the time of testing.
Performance dipped only for divided attention if the footballers had no symptoms; their
cognitive function equalled that at baseline and that of uninjured control players. On pencil and
paper neuropsychological tests footballers with symptoms performed as well as at baseline but
did not show the significant improvements evident in those without symptoms and the controls.
Footballers with symptoms took longer to return to sport, and it seemed that symptoms at
injury, symptom resolution, cognitive performance, and time before resuming training and
competition may turn out to be interrelated.
The prospective study was performed on 615 footballers, all of whom completed cognitive and
neuropsychological tests at the start to the season. Those footballers concussed during the
season, 25 with symptoms and 36 without, were retested up to 11 days after their injury, and the
controls were tested at the end of the season.
This study is one of the few to test the assumption that lack of symptoms after concussion
indicates a return to full mental fitness and cognitive functioning.
m Collie A, et al. Journal of Neurology Neurosurgery, and Psychiatry 2006;77:241–245.
148 Bakhtiary, Safavi-Farokhi, Aminian-Far
www.bjsportmed.com