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J Musculoskelet Neuronal Interact 2022
Original Article
Cross-education effect of vibration foam rolling on
eccentrically damaged muscles
Masatoshi Nakamura1, Kazuki Kasahara2, Riku Yoshida2, Kaoru Yahata2, Shigeru Sato2,
Yuta Murakami2, Kodai Aizawa2, Andreas Konrad3
1Faculty of Rehabilitation Sciences, Nishi Kyushu University, Kanzaki, Japan;
2
Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata City, Japan;
3Institute of Human Movement Science, Sport and Health, Graz University, Austria
Introduction
It is well studied that damaged onset muscle soreness
(DOMS) is caused by muscle contractions, including eccentric
contractions and intense exercise after a long sedentary
period. DOMS causes muscle soreness at palpation,
contraction, and stretching and decreases muscle strength
and range of motion (ROM)1-3. These impairments, in turn,
can influence athletic performance, reduce training quality
and adherence to resistance training, and increase the
prevalence of injury. Recent studies showed that foam
rolling (FR) and vibration FR (VFR) interventions on the
eccentrically damaged muscle could reduce muscle soreness
and counteract the loss of ROM and muscle performance4-6,
thereby effectively controlling the impairments caused by
DOMS. However, FR and VFR interventions on the damaged
muscle may lead to significant pain and discomfort.
Interestingly, a single FR intervention was reported to
increase the ROM of the non-rolling contralateral leg7,8. This
phenomenon is called the “cross-education (transfer) effect.”
Aboodarda et al. (2015) reported a non-local increase in
the pressure pain threshold (PPT) in their study9. Nakamura
et al. (2021) showed the same effect of FR intervention on
ROM in both the intervention and nonintervention sides10.
Similarly, García-Gutiérrez et al. (2018) showed that VFR
intervention helped increase the ROM on the nonintervention
side11. Taken together, these studies indicate that VFR
intervention on the nondamaged side can recover muscle
Abstract
Objectives: Previous studies showed that vibration foam rolling (VFR) on damaged muscles improves muscle soreness
and range of motion (ROM). VFR intervention can also increase the ROM and pain pressure threshold (PPT) in the non-
rolling side, known as a cross-education effect. However, this is not clear for the non-rolling side. Therefore, this study
aimed to investigate the cross-education effects of VFR intervention on ROM, muscle soreness, and PPT in eccentrically
damaged muscles. Methods: Participants were sedentary healthy male volunteers (n=14, 21.4±0.7 y) who performed
eccentric exercise of the knee extensors with the dominant leg and received 90-s VFR intervention of the quadriceps at the
nondamaged side 48 h after the eccentric exercise. The dependent variables were measured before the exercise (baseline),
before (preintervention), and after VFR intervention (postintervention) 48 h after the eccentric exercise. The Bonferroni
post hoc test was used to determine the differences between baseline, preintervention, and postintervention. Results:
Results showed that the VFR intervention on the nondamaged side 48 h after the eccentric exercise improved significantly
(p<0.05) the knee flexion ROM, muscle soreness at palpation, and PPT compared to baseline. Conclusion: VFR intervention
on the nondamaged side can recover ROM and muscle soreness in eccentrically damaged muscles.
Keywords: Cross-Transfer Effect, Contralateral Effect, Range Of Motion, Countermovement Jump, Pain Pressure Threshold
The authors have no conflict of interest.
Correspond ing author: Masatoshi Nakamura, Faculty of Rehabilitation
Sciences, Nishi Kyushu University, 4490-9 Ozaki, Kanzaki, Saga, 842-
8585, Japan
E-mail: nakamura mas@nisikyu-u.ac.jp
Edited by: G. Lyritis
Accepted 5 May 2022
Journal of Musculoskeletal
and Neuronal Interactions
Αccepted Article
Published under Creative Common License CC BY-NC-SA 4.0 (Attribution-Non Commercial-ShareAlike)
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M. Nakamura et al.: Cross-education effect of VFR
soreness and decreased ROM due to muscle damage when
the muscle damage is on only one side. The advantage of
VFR intervention on the nondamaged side is that it can cause
less pain and discomfort compared to VFR intervention on
the damaged side. However, to the best of our knowledge,
no study has thus far investigated the cross-education
effect of VFR intervention for the nondamaged side on
ROM, muscle soreness, and PPT in eccentrically damaged
muscles. According to the findings of the previous studies11,
we hypothesized that VFR intervention on the nondamaged
muscle could improve ROM, muscle soreness, PPT, muscle
strength, and jump performance in the contralateral
damaged muscle side. The results of this study suggest VFR
as an effective treatment method for cases with unilaterally
damaged muscles in athletes (e.g., in unilateral sports such
as tennis and fencing) and older adults.
Materials and Methods
Experimental Design
The outcome measurements consisted of knee flexion
ROM, maximal voluntary isometric contraction (MVC-ISO),
maximal voluntary concentric contraction (MVC-CON) torque
of knee extensor, countermovement jump (CMJ) height, pain
pressure threshold (PPT), tissue hardness, muscle soreness
at MVC-ISO, MVC-CON, and stretching. All participants
completed a bout of eccentric exercise of the knee extensors
and received 90 s VFR intervention (30 s * 3 sets) of the
nondamaged side at 48-h after the eccentric exercise4-6.
These outcomes were measured before the maximal ECC
task (baseline) and before (preintervention), and after VFR
intervention (postintervention) by the same investigator.
The postintervention measurements were performed
immediately after the VFR intervention. All measurements
were taken at the same time of the day for each participant.
Our previous study confirmed the high reliability of the
outcome variables12.
Participants
Fourteen sedentary healthy young male volunteers
participated in this study (age, 21.4±0.7 years; height,
171. 0 ±5.8 cm; body mass, 65.3±8.2 kg). All participants
had not performed habitual exercise activities and had not
been involved in any regular resistance training or flexibility
training for at least 6 months prior to participating in
this study. We excluded participants who had a history of
neuromuscular disease or musculoskeletal injury on the
lower extremities. All subjects were fully informed of the
procedures and purpose of the study and provided written
informed consent. The study was conducted in accordance
with the Declaration of Helsinki and approved by the Ethics
Committee at the Niigata University of Health and Welfare,
Niigata, Japan.
The sample size required for a one-way repeated analysis
of variance (ANOVA) according to previous studies with
a similar design4-6 (effect size=0.50, α error=0.05, and
power=0.80) using G* power 3.1 software (Heinrich Heine
University, Düsseldorf, Germany) was 14 participants.
MVC-ISO and MVC-CON
Using an isokinetic dynamometer (Biodex System 3.0,
Biodex Medical Systems Inc., MVC-ISO was measured at
two different angles, namely, 20° and 70° knee angles12.
The participants were instructed to perform a maximal
contraction of the knee extensors for 3 s at each angle two
times with a 60 s rest between trials. The average value was
adopted for further analysis. MVC-CON was measured at an
angular velocity of 60°/s for an ROM of 70° (20°–90° knee
angles) for thre e continuous MVC-CONs for the exte nsion. The
highest value among the three trials was adopted for further
analysis. Verbal encouragement was provided consistently
during all trials.
Knee Flexion ROM
Each participant was placed in a side-lying position on a
massage bed, and the hip and knee of the nonexercised leg
were flexed at 90° to prevent pelvis movement during ROM
measurements4. Next, the investigator brought the dominant
leg to full knee flexion with the hip joint in a neutral position
to the maximum pain the subject could tolerate4-6. F ina lly,
a goniometer (MMI universal goniometer Todai 300 mm,
Muranaka Medical Instruments, Co., Ltd., Osaka, Japan) was
used to measure the knee flexion ROM three times, and the
average value was used for further analysis.
Muscle Soreness
Using a visual analog scale that had a continuous 100-
mm line with “not sore at all” on one side (0 mm) and “very,
very sore” on the other side (100 mm), the magnitude of
knee extensor muscle soreness was assessed by muscle
contraction, stretching, and palpation4 - 6,13 . Both MVC-ISO
and MVC-CON were measured to assess muscle soreness
on contraction, and the average value was adopted for
further analysis. For muscle soreness during palpation, the
particip ants lay supine on a massag e bed, and the investig ator
palpated the proximal, middle, and distal points of the vastus
medialis, vastus lateralis, and rectus femoris4 - 6 ,12. Again, the
average value of the knee extensor palpation points was used
for further analysis. The ROM measurement was taken three
times to determine muscle soreness during stretching, and
the average value was used for further analysis.
PPT
An algometer measured PPT measurements (NEUTONE
TAM-22 (BT10); TRY ALL, Chiba, Japan) in the supine
position. The measurement position was set at the
midpoint between the anterior superior iliac spine and the
upper end of the patella of the dominant side for the rectus
femoris muscle. With a continuously increasing pressure,
the metal rod of the algometer was used to compress the
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M. Nakamura et al.: Cross-education effect of VFR
soft tissue in the measurement area. The participants
were instructed to immediately press a trigger when they
felt pain rather than just pressure. The value read from the
device at this time point (kilograms per square centimeter)
corresponded to the PPT. Based on previous studies14,15,
the mean value (kilograms per square centimeter) of the
three repeated measurements were taken with a 30-s
interval for data analysis.
Countermovement Jump
The CMJ height was calculated from flight time using
the jump mat system (4Assist Inc., Tokyo, Japan). The
participants started with the foot of the dominant leg on the
mat with their hands in front of their chest. From this position,
the participants were instructed to dip quickly (eccentric
phase), reaching a self-selected depth to jump as high as
possible in the next concentric phase. The landing phase
was performed on both feet. The knee of the uninvolved leg
was held at approximately 90° of the flexion16. Immediately
after three familiarization repetitions, three sets of CMJ were
performed and measured, and the maximal vertical jump
height was used for further analysis.
ECC Exercise Task
All participants performed six sets out of ten maximal
ECCs of the unilateral knee extensors (dominant leg) on
the isokinetic dynamometer4 ,12 . The participants sat on
the dynamometer chair at an 80° hip flexion angle, with
adjustable Velcro straps fixed over the trunk, pelvis, and
thigh of the exercised limb. The participants were instructed
to perform the maximal ECC from a slightly flexed position
(20°) to a flexed position (110°) at an angular velocity of
60 °/ s 4 ,12 . After each ECC, the lever arm passively returned
the knee joint to the starting position at 10°/s, which gave
a 9 s rest between contractions. Each set was repeated ten
times, and a 100-s rest period was allotted between the
six sets. The participants received verbal encouragement
during each ECC to generate maximum force.
Vibration Foam Rolling Intervention
A foam roller (Stretch Roll SR-002, Dream Factory,
Umeda, Japan) was used for the VFR intervention. Before
the VFR intervention, a physical therapist instructed
the participants on how to use the foam roller. The VFR
intervention was performed in three 30-s bouts with a
30-s rest between each set at 35 Hz. The participants
were instructed lie the plank position with the foam roller
at the most proximal portion of the quadriceps of the
nondamaged leg only. Here we defined one cycle of VFR
intervention as one distal rolling plus one subsequent
proximal rolling movement, whereas the frequency was
defined as 15 cycles per 30 s (for a total of 45 cycles
in three sets) and measured using a metronome (Smart
Metronome; Tomohiro Ihara, Japan). One cycle of VFR
intervention was defined as the point between the top of
the patella and the anterior superior iliac spine under the
direct supervision of investigators. The participants were
asked to place as much of their body mass on the roller as
tolerable.
Statistical Analysis
SPSS (version 24.0; SPSS Japan Inc., Tokyo, Japan)
was used for statistical analysis. The data distribution was
assessed using the Shapiro–Wilk test, and we confirmed that
the data followe d a normal distributio n. Significant d ifferences
in all variables were assessed using a one-way repeated
ANOVA. When a significant effect was found, the Bonferroni
post hoc test was used to determine the differences between
measurements taken at baseline, preintervention, and
postintervention. Additionally, we calculated the effect size
(Cohen’s d) as differences in the mean value divided by
the pooled standard deviation (SD) between the pre- and
postintervention in each group, in which a d of 0.00–0.19
was considered as trivial, 0.20–0.49 as small, 0.50–0.79
as moderate, and ≥0.80 as large17,18. Differences were
considered statistically significant at an alpha of P<0.05. The
data are presented as mean ± SD.
Table 1. Changes (mean±SD) in knee flexion range of motion (ROM), maximal voluntary isometric contraction torque of knee extensor (MVC-
ISO), maximal voluntary concentric contraction torque (MVC-CON) at 60°/s, countermovement jump (CMJ) height before maximal eccentric
contraction task (baseline), pre- and post-vibration foam rolling for non-damaged side. The one-way repeated analysis of variance (ANOVA)
results (p, and F-values and partial η2 (ηp
2)) are shown in the bottom column.
Knee flexion ROM (deg) MVC-ISO (Nm) MVC-CON (Nm) CMJ height (cm)
Baseline 136 . 3 ±5.5 155.2±26.3 161 . 6 ±2 5 .1 19.0 ±2.9
Pre-intervention 125.9 ±9.9* 104. 6±22. 5* 111 . 7 ±28.8* 15.7±2.9*
Post-intervention 130.4±7.6*,# 10 4 .8±24.6* 11 5 . 4 ±29.7* 16 .7±3.1*
One-way repeated
ANOVA
p<0.01, F=19.2,
ηp
2=0.596
p<0.01, F=96.3,
ηp
2= 0. 8 81
p<0.01, F=60.0,
ηp
2=0.822
p<0.01, F=14.6,
ηp
2=0.529
*: A significantly (P<0.05) different from the baseline value; #: A significantly (P<0.05) different from the pre-intervention value.
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M. Nakamura et al.: Cross-education effect of VFR
Results
Table 1 shows the knee flexion ROM, MVC-ISO, MVC-CON,
and CMJ at baseline, pre-, and post-VFR for the nondamaged
side. The one-way ANOVA indicated the main effects for all
variables. As a result of the post hoc test, all variables were
significantly decreased after the ECC task. The knee flexion
ROM was improved a fter VFR interve ntion on the nond amaged
side (p<0.01, d=0.51). However, the postintervention value of
the knee flexion ROM was significantly lower than the baseline
value (p=0.01). On the other hand, the VFR intervention on
the nondamaged side did not induce significant changes in
MVC-ISO (p=1.00, d=0.01), MVC-CON (p=0.23, d=0.12) and
CMJ height (p=0.16, d=0.32).
Table 2 shows PPT and muscle soreness at MVC-ISO, MVC-
CON, stretching, and palpation at baseline, pre-, and post-VFR
for the nondamaged side. The one-way ANOVA indicated the
main effects for all variables. As a result of the post hoc test,
all variables in the preinter vention were changed significantly
compared to the baseline measurement. However, VFR
intervention on the nondamaged side significantly recovered
PPT (p=0.048, d=0.56), muscle soreness at MVC-ISO
(p=0.024, d=–0.35), MVC-CON (p=0.02, d= –0.26), and
palpation (p=0.02, d=–0.37), except for muscle soreness at
stretching (p=0.15, d=– 0.38). Moreover, the postintervention
value of muscle soreness at MVC-ISO, MVC-CON, and
palpation was significantly higher than the baseline value.
Discussion
This study investigated the cross-education effect of
VFR intervention on the eccentrically damaged muscles of
fourteen healthy male subjects. Our results showed that
the VFR intervention of the nondamaged side was able to
recover the knee flexion ROM, PPT, and muscle soreness.
Thus, it could be an effective treatment for DOMS via VFR
intervention on the nondamaged side in athletes (e.g., in
unilateral sports such as tennis and fencing) and older adults.
Our results showed that the VFR intervention of the
nondamaged side was able to significantly recover PPT and
muscle soreness at MVC-ISO, MVC-CON, and palpation.
VFR was able to selectively activate, through pressure and
vibration, rapid muscle contractions that improved the pain
sensation19. A previous study also showed reduced pain
perception af ter FR intervention, as follows: 1) ascending pain
inhibitory system (gate theory of pain), 2) the descending
anti-nociceptive pathway (diffuse noxious inhibitory control
[DNIC]), and 3) the autonomic nervous system9. Although
the detailed mechanism of the analgesic effect of VFR
intervention on the nondamaged muscle was unclear in this
study, the mechanism described above was able to reduce
muscle soreness in the damaged muscle side without direct
intervention. However, muscle soreness at stretching could
not significantly change after VFR intervention on the
nondamaged side. This study measured knee flexion ROM
to the maximum angle that the participants could tolerate.
Therefore, muscle soreness at stretching did not change
significantly. Thus, the decreased muscle soreness at
stretching after the VFR intervention on the nondamaged
side could have increased knee flexion ROM.
Interestingly, our results showed that ROM was recovered
but not in muscle strength or CMJ height after VFR
intervention on the nondamaged side. Our previous study
showed that FR intervention on the damaged muscle side
could recover muscle strength4, but VFR intervention could
not6. However, VFR intervention could recover the CMJ
height6. The reason for the discrepancy between the current
study and the previous studies4,6 is unclear. However, it is
possible that direct FR or VFR intervention on a damaged
muscle might affect can strength and jump performance.
Hence, if the goal of an athlete is to fully regain strength after
muscle damage, a combi nation of FR and VFR on the d amaged
muscle is recommended. Further studies are needed to
investigate the discrepancy between the direct effect and
the cross-education effect of FR and/or VFR intervention on
muscle strength and jump performance.
Kasahara et al. (2022) investigated the effect of direct
VFR intervention on the damaged muscle side using the
same protocol as this study. In our study, the changes from
Tabl e 2 . Changes (mean±SD) in pain pressure threshold (PPT), muscle soreness at maximal voluntary isometric contraction (MVC-ISO),
maximal voluntary concentric contraction (MVC-CON), stretching, and palpation before maximal eccentric contraction task (baseline), pre-
and post-vibration foam rolling for the non-damaged side. The one-way repeated analysis of variance (ANOVA) results (p, and F-values and
partial η2 (ηp
2)) are shown in the bottom column.
Ppt (kg) Muscle soreness at
mvc-iso (mm)
Muscle soreness at
mvc-con (mm)
Muscle soreness at
stretching (mm)
Muscle soreness at
palpation (mm)
Baseline 2.8±1.0 10. 2±11 . 6 8.3±9.6 2.3±3.9 7.4 ±5.2
Pre-intervention 1.8 ±1.2* 30.6±16.9* 28.6±21. 2* 34.4±14.7* 41.6 ±19.9*
Post-intervention 2.4±1.1#24.8±16.2 *, # 23.4±19. 5*,# 2 9.1±13 . 3* 34.6±18.6*,#
One-way repeated
ANOVA
p<0.01, F=12.6,
ηp
2=0.492
p< 0.01, F =16.7,
ηp
2=0.562
p<0.01, F=13.5,
ηp
2= 0. 51
p<0.01, F=49.9,
ηp
2=0.793
p<0.01, F=39.9,
ηp
2=0.754
*: A significantly (P<0.05) different from the baseline value; #: A significantly (P<0.05) different from the pre-intervention value.
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M. Nakamura et al.: Cross-education effect of VFR
pre- to post-VFR intervention for the nondamaged side were
3.8±3.7% (d=0.51) in the knee flexion ROM, 0.72±0.8 kg
(d=0.56) in PPT, and –7.0±7.6 mm (d=–0.37) at muscle
soreness at palpation. On the other hand, the previous study
showed that the changes from pre- to post-VFR intervention
for the damaged side were 6.1±4.4% (d = 0.68) in knee
flexion ROM, 1.1±0.9 kg (d=0.93) in PPT, and –15.2±10.4
mm (d=–1.27) at muscle soreness at palpation. These
differences could be related to the magnitude of pain or
discomfort during the VFR inter vention. VFR intervention on
the damaged muscle side caused greater pain and discomfort
than VFR interventions on the nondamaged side, resulting in
greater ROM and muscle soreness changes. Therefore, if an
individual can tolerate the pain or discomfort brought on by
VFR intervention on the damaged muscle side, then direct
VFR intervention on the damaged muscle side will be more
effective th an intervention on the nonda maged side. However,
if the pain and discomfort are too severe for VFR intervention
on the damaged muscle side. In that case, it may be more
effective to first intervene on the nondamaged muscle
side and then carry out VFR intervention on the damaged
muscle side after the pain is relieved. Future studies should
investigate VFR intervention’s effect on the damaged side
after VFR intervention on the nondamaged side on changes
in these variables.
There were some limitations in this study. First, although
we followed the suggestions of the a prioiri sample size
calculation and recruited 14 participants, the sample might
have been at the lower border (i.e., small post-hoc power).
Second, the participants in this study were not athletes but
sedentary healthy young males. Thus, future studies should
investigate the effects of VFR on nondamaged muscle in
athletes participants in a larger sample size.
In conclusion, VFR intervention on the nondamaged side
was able to induce a cross-education effect, i.e., recover
ROM and muscle soreness but not muscle strength and
jump performance. These findings indicate that if it is too
painful to intervene directly on the damaged muscle side, it
may be a practical course of treatment to inter vene on the
nondamaged muscle side.
Fun di ng
This study was not funded by the funder listed in Open Funder
Registry. We conducted this study together with Dream Factory Co.,
Ltd. However, the industry funder had no role in the study design, data
collection, and data analysis or in the preparation of this manuscript.
Also, this work was supported by JSPS KAKENHI with grant number
19K19890 (Masatoshi N akamura) and the Austrian Science Fund
(FWF) Project J 4484 (Andreas Konrad).
Ethical Approval
This study was approved by the Ethics Committee of the Niigata
University of Health and Welfare, Niigata, Japan (Procedure #18220),
and has complied with the requirements of the Declaration of Helsinki.
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