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An ergonomic comparison of rowing machine designs: Possible implications for safety

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Abstract and Figures

Ergometer training is a common cause of injuries in rowers. A randomised crossover study comparing two power head designs was carried out to examine ergonomic risk factors. Six elite male rowers undertook 20 minute fatiguing rowing pieces with both fixed and floating power heads. A CODA MPX infrared telemetric motion analysis detector and the ergometer's interface were used to measure displacement, force, work performed, and power output. There was no significant difference in the total work performed, power per stroke, or metabolic load between the two ergometer designs. Fatigue was shown by a mean (SEM) fall of 9.7 (0.79) W/stroke (95% confidence interval (CI) 8.0 to 11.5) between minutes 8-10 and minutes 16-18 (p<0.001). The stroke length was 53 (13) mm (95% CI 18 to 89) longer with the fixed power head (p<0.02). With fatigue, the stroke with the fixed power head lengthened at the "catch" (beginning of the stroke) by 19.5 mm (p<0.01) and shortened at the finish of the stroke by 7.2 mm (p<0.05). No significant changes in stroke length were seen with the floating power head. The mean force per stroke was 12.1% (95% CI 3.0 to 21.2) (27.3 (8.0) N) higher with the power head fixed versus floating (p<0.02). It is postulated that longer stroke lengths and greater forces are risk factors for soft tissue injuries. Further research into whether floating power head rowing ergometers are associated with lower injury rates than fixed power head designs is now needed.
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ORIGINAL ARTICLE
An ergonomic comparison of rowing machine designs:
possible implications for safety
I A Bernstein, O Webber, R Woledge
.............................................................................................................................
Br J Sports Med
2002;36:108–112
Objectives: Ergometer training is a common cause of injuries in rowers. A randomised crossover study
comparing two power head designs was carried out to examine ergonomic risk factors.
Methods: Six elite male rowers undertook 20 minute fatiguing rowing pieces with both fixed and float-
ing power heads. A CODA MPX infrared telemetric motion analysis detector and the ergometer’s inter-
face were used to measure displacement, force, work performed, and power output.
Results: There was no significant difference in the total work performed, power per stroke, or
metabolic load between the two ergometer designs. Fatigue was shown by a mean (SEM) fall of 9.7
(0.79) W/stroke (95% confidence interval (CI) 8.0 to 11.5) between minutes 8–10 and minutes 16–18
(p<0.001). The stroke length was 53 (13) mm (95% CI 18 to 89) longer with the fixed power head
(p<0.02). With fatigue, the stroke with the fixed power head lengthened at the “catch” (beginning of
the stroke) by 19.5 mm (p<0.01) and shortened at the finish of the stroke by 7.2 mm (p<0.05). No sig-
nificant changes in stroke length were seen with the floating power head. The mean force per stroke
was 12.1% (95% CI 3.0 to 21.2) (27.3 (8.0) N) higher with the power head fixed versus floating
(p<0.02).
Conclusions: It is postulated that longer stroke lengths and greater forces are risk factors for soft tissue
injuries. Further research into whether floating power head rowing ergometers are associated with
lower injury rates than fixed power head designs is now needed.
E
rgometer training on rowing machines has been thought
by elite rowers to be a common cause of land training
injuries, particularly back injuries.
1
It is still not known
whether low back pain occurs more often in rowers than the
general population. In elite rowers, more than 50% of injuries
occurred off the water during land based training.
12
Injuries in
rowing are rare events (1 per 1000 hours) compared with
other sports.
2
However, when they do occur, they cause elite
rowers to lose an average of 24 days of training a year
1
often
preventing selection for the national teams.
2
At the elite level,
training sessions on most days of the week involve continuous
rowing on the water for 60–90 minutes at intensities just
below the anaerobic threshold.
3
Ergometers are often used for
training and assessing rowers. In these rowers, land based
training carries a 10-fold higher risk of injury per hour than
water based training,
2
the leading causes suggested being
weights and ergometer training.
1
Stationary rowing ergometers (fixed power head designs)
are the most commonly used type in this country. Other
designs are based on mounting the whole ergometer on
wheels (wheeled ergometer) or mounting the power head on
rollers so that it can move independently of the seat on the
slide track (floating power head design). The mechanical
characteristics of these designs have been compared.
45
Float-
ing power head and wheeled ergometer designs more closely
simulate the mechanics and kinetic energy characteristics of
rowing on the water than do stationary ergometers.
45
However, these studies did not examine risk factors for
injuries.
In repetitive lifting, an action similar to rowing, muscle
fatigue rather than primary failure of passive structures was
the most important factor leading to instability of the spine.
6
A substantial part of the bending moment in the flexed spine
was resisted by passive structures as muscles fatigued with
repetitive lifting.
7
Gradual disc prolapse is an injury reported
in rowers.
8
Perhaps this is a result of repetitive lumbar flexion
under load because this was shown to lead to gradual disc
prolapse in a cadaveric study.
9
Fatigue has been shown to lead
to loss of coordination in rowers on the water.
10
However, there
has been no published work on the relation between fatigue,
coordination, and injury on rowing ergometers.
We therefore conducted a randomised crossover study to
examine the ergonomic differences between two commonly
used rowing ergometer power head designs. The trial design
allowed us to study the effects of fatigue as well as account for
the large variation between subjects.
METHODS
Study population
Six elite male oarsmen as classified by the Amateur Rowing
Association
11
(mean age 30 (range 22–40); mean (SD) height
1.87 (0.07) m; mean (SD) mass 80 (11) kg) volunteered for the
study. Exclusion factors were: a history of serious injury,
recent illness, and inexperience on the rowing ergometers
used. Prior ethical approval was granted from the Royal
National Orthopaedic Hospital Trust ethics committee. Signed
consent was obtained from each subject.
Equipment and methods
The subjects each performed two 20 minute rows on a
RowPerfect rowing ergometer (Care RowPerfect BV, JV Hard-
enberg, The Netherlands) in the laboratory. This ergometer
has a “floating” power head—that is, the footplate with the
power head unit and the seat are both mounted on the slide
track and are thus free to move independently (fig 1). The
mass of the power head (about 17 kg) is similar to that of a
section of a boat containing one oarsman. To simulate a fixed
power head ergometer, the floating head was clamped at one
end. The chain was placed on the larger of two cogwheels, and
a 39 cm disc was used to set the resistance on the fly wheel for
all pieces. The display settings were set to simulate a coxless
four boat type. A Polar surface chest monitor and telemetric
sensor was connected to the ergometer interface. The ergom-
eter interface provides force data, sampled every 20th stroke,
See end of article for
authors’ affiliations
.......................
Correspondence to:
Dr Bernstein, Gordon
House Surgery, 78 Mattock
Lane, London W13 0NZ,
UK; ibernstein@
gordonhouse.freeserve.co.uk
.......................
108
www.bjsportmed.com
derived from measurement of the speed of the flywheel. The
accuracy and repeatability obtained from comparison with a
calibrated force plate was ± 0.1%.
The subjects were randomised (without replacement) into a
crossover study design so that half started with a fixed power
head and the other half with a floating power head. The sub-
jects stretched and warmed up on the ergometer for at least 10
minutes before each row. A break of at least 45 minutes
between the two pieces was given for rest and rehydration
while the power head was changed. The subjects were given a
minimum pulse rate to maintain during the pieces, to ensure
that they were exercising above their anaerobic thresholds and
developed fatigue. This was determined by previous physio-
logical testing at the British Olympic Medical Centre,
including measurement of capillary blood lactate levels. The
subjects were asked to use the first several minutes to achieve
the target pulse rate and then to keep the pulse rate steady.
Displacements were measured by a CODA MPX motion
analysis system (Charwood Dynamics Ltd, Rothley, Leicester-
shire, UK) using infrared active markers fixed to the subjects’
skin or to the ergometer by adhesive tape. Twenty one markers
were in fact used, but only data from markers on the handle
and footplate are reported in this paper. Three dimensional
coordinates were obtained for each marker at 100 Hz. The
standard deviation of repeated measurements was less than
0.2 mm, and the accuracy obtained from a calibration grid was
± 0.3 mm. Forty second samples of rowing were taken every
two minutes. Each acquisition period was divided into stroke
cycles. Each cycle was defined by the maximum horizontal
displacement of the handle with respect to the footplate. This
defined the beginning of the stroke (“the catch”). Incomplete
cycles at the beginning and end of the data acquisition period
were discarded. The data were averaged across all of the com-
plete cycles. It was not possible to synchronise data from the
CODA and the ergometer interface, which were therefore ana-
lysed separately.
Fatigue was examined by comparing a time period after the
anaerobic threshold was reached and a period towards the end
of the piece which was not affected by the subjects “sprinting”
to the line. Some data were not obtained successfully.
Therefore the periods for comparison of the ergometer data
were from 8 to 10 minutes and from 16 to 18 minutes,
amounting to two minute samples. The periods for the CODA
data were from 7 to 12 minutes and from 13 to 18 minutes,
each period encompassing three 40 second data acquisitions,
amounting to a total of a two minute sample. The length of the
periods was chosen to include sufficient data for the repeated
measures analysis.
Main outcome measures
The outcome measures recorded from the ergometer interface
were: power output; work performed; force displacement
curves; pulse rate; stroke rate; time elapsed; stroke number.
Stroke length was recorded by the CODA system.
Missing data
The first ten minutes of ergometer data for one subject was
lost as the result of computer failure. The remaining data for
that row was used for the analysis, the sampling periods being
11–13 minutes and 17–19 minutes.
Statistical analysis
Significance tests were based on the paired t test for the effects
of fatigue on the means of the ergometer derived variables.
Normalised peak force data were examined using an unpaired
t test. The CODA derived stroke length data were examined
using two way analysis of variance with replication. A grid of
t tests, as applied to the special case of crossover trials,
12
exam-
ined the differences between the power head design, the order
of the trials, and the interaction between power head design
and trial order. A repeated measures calculation was used
where appropriate. The normality of the data was examined
with a Kolmogorov-Smirnov test.
Statistical power
Statistical significance was defined at the two tailed p = 0.05
level. Confidence limits at the 95% level are presented where
appropriate. The final data set generated more than 85% power
to detect the observed changes in stroke length and
differences in normalised force displacement curves between
the fixed and floating power heads.
RESULTS
Table 1 compares the key characteristics of the subjects in each
group. Table 2A classifies the main ergometer and pulse rate
data by power head design. The same work was performed
with both power heads. Pulse rates were above the target rates
for the second half of each piece. Table 2B classifies the same
data by first versus second pieces. There were no significant
differences in the time to reach target pulse rates or mean
pulse rates during the period from 14 to 19 minutes compar-
ing floating versus fixed power heads or first versus second
pieces.
Subjects showed a mean (SEM) fall of 9.7 (0.79) W/stroke
(95% confidence interval (CI) 8.0 to 11.5) between minutes
8–10 and minutes 16–18 (p<0.001). There was no significant
difference in this fall between the fixed and floating power
heads. Further effects of fatigue were indicated by a fall in
total work and mean power per stroke between the first and
second pieces (table 2B).
Figure 1 Photographs showing rowing movements with the power
head fixed and floating. Courtesy of C. Pekkers.
Table 1 Characteristics of subjects in each group
Characteristic Group 1 Group 2
No of subjects 3 3
Age (years) 28.7 (5.9) 32.7 (6.4)
Height (m) 1.8 (0.03) 1.9 (0.1)
Weight (kg) 77.8 (4.2) 81.9 (16.1)
Target pulse (beats/min) 172.0 (2.7) 170.7 (3.1)
Values are mean (SD) of the group. The significance of the
differences between the groups was tested with Student’s
t
test. No
significant differences were found.
Comparison of rowing ergometer designs 109
www.bjsportmed.com
Stroke length
Analysis of the CODA data showed that the stroke length,
after target pulse rates were achieved, was 53 (13) mm (95%
CI 18 to 89) longer with the fixed than with the floating
power head (p<0.02). In addition to this observation, there
were further changes in the horizontal handle displacement
(stroke length) as the pieces progressed with the fixed power
head only. Specifically, in the horizontal plane, the handle
went further beyond the footplate at the beginning of the
stroke (stroke lengthening at the catch) and also finished
nearer the footplate at the end of the stroke (stroke shorten-
ing at the finish) (table 3A). Comparison of the stroke length
with first versus second piece showed no increase during the
first piece but a small increase during the second piece (table
3B).
Force data
The force versus handle displacement data from the ergometer
interface was sampled every 20th stroke. Figure 2 shows typical
curves for the mean data for one rower. The mean force per stroke
across all the subjects was 12.1% (95% CI 3.0 to 21.2) (27.3 (8.0)
N) higher with the power head fixed versus floating (p<0.02).
To examine the differences in shapes between fixed and
floating heads, the curves were normalised to give them the
same area. This was achieved by dividing each point on the
curve by the mean value for the whole curve. Figure 3 shows
the normalised curves for the same rower as shown in fig 2.
The mean work performed to half of the handle displacement
(the area under the curves to the left of the vertical line in fig
3) was 64.1% of the total work performed with the fixed power
head and 67.8% with the floating power head. The difference
Table 2 Measurements made during rowing pieces from the ergometer interface
Variable Fixed Floating Difference (95% CI) Standard error p Value
(A) Comparison between fixed and floating power heads
Work performed (kJ) 368 365 2 (8to13) 4 NS
No of strokes 464 506 42 (15 to 69) 10 <0.02
Power per stroke (W) 314 308 6 (11 to 23) 6 NS
Work performed per stroke (J) 813 728 84 (55 to 113) 10 <0.001
Pulse rate: minutes 14–19 (beats/min) 180 183 3(7to1) 1 NS
Time to target pulse (s) 449 392 57 (174 to 287) 83 NS
Variable 1st Piece 2nd Piece Difference (95% CI) Standard error p Value
(B) Comparison between first and second pieces
Work performed (kJ) 371 361 10 (0.3 to 20) 4 <0.06
No of strokes 477 492 15 (42 to 12) 10 NS
Power per stroke (W) 320 301 19 (2 to 36) 6 <0.05
Work performed per stroke (J) 797 744 52 (23 to 81) 10 <0.01
Pulse rate: minutes 14–19 (beats/min) 180 183 3(6to1) 1 NS
Time to target pulse (s) 457 385 72 (158 to 303) 83 NS
Significance is given by two way
t
test analysis. Values are means, differences and standard errors of the differences (95% confidence intervals).
Table 3 Change during the piece in length at each end of the stroke measured by the CODA system
Fixed power head Floating power head
Length change (mm) p Value Length change (mm) p Value
(A) Comparison between fixed and floating power heads
Catch 19.5 (32.6) <0.01 3.5 (36.3) NS
Finish 7.6 (27.2) <0.05 4.9 (30.8) NS
First piece Second piece
Length change (mm) p Value Length change (mm) p Value
(B) Comparison between first and second pieces
Catch 7.6 (50.0) NS 8.4 (12.4) <0.001
Finish 2.3 (41.4) NS 0.4 (7.8) NS
Values are the mean differences (SD) between the average displacements during minutes 7–12 compared with minutes 13–18. Positive numbers indicate
movement towards the power head. Significance is given by two way analysis of variance with replication.
Figure 2 Example of the mean force versus handle displacement
plots with the power head fixed and floating for one rower. Data are
averaged over one piece.
600
450
300
0
150
2.0
Handle displacement (m)
Floating power head
Fixed power head
Force (N)
1.51.00.0 0.5
Figure 3 Example of the normalised mean force versus handle
displacement plots with the power head fixed and floating for the
same rower as in fig 2. Data averaged over the whole of one piece.
The area under each curve to the left of the vertical line represents
percentage of total work performed to half of the total handle
displacement.
3
2
1
0
0.5
2.0
Handle displacement (m)
Normalised force
1.51.00.0 0.5
2.5
1.5
Normalised floating average
Normalised fixed average
110 Bernstein, Webber, Woledge
www.bjsportmed.com
was 3.7 (1.2)% (95% CI 0.67% to 6.80%) (p<0.05). In contrast
with the raw data, the peak force was higher in all subjects
with the floating power head (p<0.05). In five out of six sub-
jects, the peak force occurred earlier in the stroke with the
floating power head compared with the fixed power head.
DISCUSSION
Differences between the force displacement profiles on fixed
compared with floating power head rowing ergometers have
been found. The stroke length was longer on the fixed power
head ergometer than the floating power head. The stroke
length increased further, particularly at the catch, with fatigue
on the fixed power head but not the floating power head. The
fixed power head ergometer led to higher mean forces being
developed for the same metabolic load and total work
performed. These differences may increase the risk of injury
when training at submaximal loads on fixed power head
ergometers compared with floating power head ergometers.
Discussion of method
The randomised crossover design reduced the effect of fatigue
being carried over from the first to the second piece. However,
this could be reduced further by performing the pieces on
separate days.
Critical to the design of the study was the need to reproduce
fatigue. Urhausen and colleagues
13
have validated the use of
pulse rates for determining exercise intensity in relation to
blood lactate measurements in rowers, on both the water and
a rowing ergometer. As pulse rate is approximately linearly
related to V
O
2
, we concluded that we had produced adequate
fatigue, above the subjects’ anaerobic threshold, with this pro-
tocol. The subjects invoked a variety of adaptations to
maintain power output in the face of fatigue. In spite of these
adaptations, we still observed a small fall in the power output
per stroke within the pieces.
Work performed
The total work performed over the whole piece was the same
with both power heads, consistent with setting the same tar-
get pulse rates for each piece. The stroke rate was lower and
the work performed per stroke was higher with the power
head fixed (table 2A). This would explain the observed differ-
ence in the areas under the force displacement curves in fig 2,
which represent the mean work performed per stroke. The
power per stroke was defined as the work performed per
stroke divided by the time for each stroke. The difference in
stroke rate accounted for the observation that the power per
stroke was similar with both power heads.
Stroke length and biomechanics
The stroke length was 53 mm longer with the power head
fixed. Following the principle of the conservation of momen-
tum, the kinetic energy of the body in the static case can be
shown to be much higher than the kinetic energy of the body
plus power head in the floating case.
14
The kinetic energy of
the moving masses (given by 0.5mv
2
) has to reduce to zero at
each end of the stroke and is higher by a factor of about 6 (or
about 60 J per stroke) for the fixed power head. The kinetic
energy is likely to be absorbed by muscles working eccentri-
cally to decelerate the moving masses. The work-energy theo-
rem predicts that the distance taken to reduce the kinetic
energy to zero will be further when the kinetic energy is
higher. This is consistent with our observations of longer
stroke lengths with the power head fixed.
The longer stroke lengths with the power head fixed
presents a possible risk factor for injury to the musculotendi-
nous junction.
15
This would be exacerbated by our observation
that fatigue caused further lengthening at the beginning of
the stroke. Lengthening of the back extensor muscles in row-
ers may cause the transference of loads to the posterior
viscoelastic structures of the vertebral units. This has been
observed with fatigue in repetitive lifting studies.
7
If studies of
activation of these muscles confirm their role in decelerating
the body at each end of the stroke (as seen with repetitive
bending
15
), this would provide a plausible link to the produc-
tion of back injuries.
Mair and colleagues
15
showed that fatigue in muscles work-
ing eccentrically resulted in a reduction in their ability to
absorb kinetic energy and an increase in their length before
being irreversibly damaged. This may explain the increase in
stroke length with fatigue that was observed with the fixed
power head. When muscles are working eccentrically, a
smaller proportion of the fibres are active than when the same
force is developed concentrically.
16
Therefore the force is
distributed across fewer fibres leading to a greater stress (force
per unit area), which is potentially damaging.
Force displacement curves
Our normalised force displacement curves (fig 3) concord with
the findings of Hänyes and Lippens.
17
They show that the force
on the handle rose later with a fixed power head ergometer
compared with the forces in a boat, similar to our comparison
between fixed and floating power heads. Rekers
4
showed directly
that the force displacement curves were very similar in size and
shape when a floating power head was compared with a boat.
4
In fig 2, the mean forces developed during the power phase
were significantly higher with the power head fixed. As
fatigue developed, some of these forces could be transferred to
passive viscoelastic structures (tendons, ligaments, cartilage,
and intervertebral discs) leading to permanent deformation.
7
Theoretical calculations have shown that the forces within the
body may vary by much greater amounts than those observed
on the handle in changing the power heads.
4
Therefore there
may be a higher chance of injury with the power head fixed.
The earlier increase in force development during the stroke
with the power head floating (fig 3) was predicted from theo-
retical considerations.
414
With the power head fixed compared
with floating, much of the initial force developed on the foot-
plate would be dissipated in accelerating the whole body mass
before that force could appear on the handle.
Further study
Further analysis of our data will allow us to calculate the kinetic
energy of the system to test the theoretical arguments above.
Future work using this experimental setup could yield
information about changes in coordination and accessory move-
ments with fatigue to identify further risk factors for injury.
Conclusion
The reduction in injury risk obtained by using floating power
head ergometers instead of fixed power head ergometers can-
not be quantified here. However, given the trend towards low
intensity long distance training, we would expect further
research to find that changing to floating power head ergom-
eters would reduce injuries attributable to ergometer training.
ACKNOWLEDGEMENTS
IB was funded by a Department of Health grant as part of the funding
towards an MSc in musculoskeletal medicine and osteopathy at Uni-
versity College, London. The manufacturer of the ergometer has
posted photographs comparing the fixed and floating power heads at
www.rowperfect.com
Take home message
The stroke length is longer and the mean forces are higher
on fixed compared with floating power head ergometers.
This could increase the risk of injury. Therefore direct
research into injury rates with the different ergometers
would be very desirable.
Comparison of rowing ergometer designs 111
www.bjsportmed.com
.....................
Authors’ affiliations
I A Bernstein, O Webber, R Woledge, UCL Institute of Human
Performance, Royal National Orthopaedic Hospital Trust, Brockley Hill,
Stanmore, Middlesex HA7 4LP, UK
Conflicts of interest: The ergometer was donated to the laboratory by the
manufacturer who was approached only after the design of the project
and the testing protocol had been established.
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rowing/physics.html. Updated 15/2/99.
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BASEM 2002 CONGRESS .............................................................................
The Aircast Travelling Fellowship 2002
T
he Fellowship, funded by Aircast Limited Partnership is open to Medical Practitioners under the age
of 40 years, as of 1 November 2002, for unpublished original work relevant to sport and exercise
medicine.
The work should include a structured abstract and be presented in the standard format of introduction,
methods, results, discussion, conclusion, references, and should include acknowledgement of support
received. The abstract should be approximately 250 words and the body 5000 words. Submissions should
be posted to the address below to arrive no later than 1 August 2002.
The fellowship will allow the holder to spend two weeks in a medical centre of excellence anywhere in
the world appropriate to the award holder’s interests. Receipted expenses including the airfare will be
awarded to a maximum of £2000.00. The holder will be expected to give a 20 minute presentation of his
or her work, as submitted, at the BASEM Annual Congress at The Low Wood Hotel, Windermere on Fri-
day 11 October 2002, at 5.45pm.
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112 Bernstein, Webber, Woledge
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... Despite mechanical differences between the Biorower and other dynamic linear ergometers previously studied, the reported values in the rowing length corroborate the data from the current study, since the Biorower consistently produced shorter lengths throughout the protocol, possibly attributed to variations in technique between the two ergometers [15,35]. On the Biorower ergometer, the rower must abduct the shoulder horizontally to follow the angular movement of the oar handle, whereas on the Concept2, the rower follows a linear motion, increasing the rowing length ( Figure 2). ...
... The risk of injury arises from repetition and the transfer of load to the lower back muscles, particularly during prolonged exercise, with the lumbar spine being the most frequently injured region in rowing (2-53%) [16,35,37]. The potential injury risk is supported by the prone plank results, which show that muscle function remains impaired on the Concept2 from 5 to 30 min after exercise compared to the Biorower [24]. ...
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We aimed to conduct a biophysical comparison of angular (Biorower) and linear (Concept2) rowing ergometers across a wide spectrum of exercise intensities. Sixteen (eleven male) skilled rowers, aged 29.8 ± 8.6 and 23.6 ± 1.5 years, with international competitive experience, performed 7 × 3 min bouts with 30 W increments and 60 s intervals, plus 1 min of all-out rowing on both machines with 48 h in between. The ventilatory and kinematical variables were measured breath-by-breath using a telemetric portable gas analyzer and determined using a full-body markerless system, respectively. Similar values of oxygen uptake were observed between ergometers across all intensity domains (e.g., 60.36 ± 8.40 vs. 58.14 ± 7.55 mL/min/kg for the Biorower and Concept2 at severe intensity). The rowing rate was higher on the Biorower vs. Concept2 at heavy and severe intensities (27.88 ± 3.22 vs. 25.69 ± 1.99 and 30.63 ± 3.18 vs. 28.94 ± 2.29). Other differences in kinematics were observed across all intensity domains, particularly in the thorax angle at the finish (e.g., 19.44 ± 4.49 vs. 27.51 ± 7.59 • for the Biorower compared to Concep2 at heavy intensity), likely due to closer alignment of the Biorower with an on-water rowing technique. The overall perceived effort was lower on the Biorower when compared to the Concept2 (14.38 ± 1.76 vs. 15.88 ± 1.88). Rowers presented similar cardiorespiratory function on both rowing ergometers, while important biomechanical differences were observed, possibly due to the Biorower's closer alignment with an on-water rowing technique.
... Research into the kinematics of rowers shows many studies that detected differences in stroke rowing between athletes (e.g., junior vs. senior or elite vs. beginning) [1,8], between types of rowing ergometers (e.g., fixed head vs. moving head) [9], and between different stroke rates [10]. ...
... Each test session consisted of a sequence of 10 consecutive strokes at the stroke rate of 20 strokes/min (spm) for the first test session (T20) and 30 strokes/minute (spm) for the second test session (T30), respectively. The choice to adopt the stroke rates of 20 and 30 spm for the test sessions was based on the fact that these cadences are within the typical range of training and competition [9,22]. ...
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Background: Research on biomechanics in rowing has mostly focused on the lumbar spine. However, injuries can also affect other body segments. Thus, the aim of this pilot study was to explore any potential variations in the kinematics of the cervical spine during two different stroke rates on the rowing ergometer in young rowers. Methods: Twelve young rowers of regional or national level were recruited for the study. The experimental protocol consisted of two separate test sessions (i.e., a sequence of 10 consecutive strokes for each test session) at different stroke rates (i.e., 20 and 30 strokes/min) on an indoor rowing ergometer. Kinematics of the cervical spine was assessed using an inertial sensor capable of measuring joint ROM (angle of flexion, angle of extension, total angle of flexion–extension). Results: Although there were no differences in the flexion and total flexion–extension movements between the test sessions, a significant increase in the extension movement was found at the highest stroke rate (p = 0.04, d = 0.66). Conclusion: Young rowers showed changes in cervical ROM according to stroke rate. The lower control of the head during the rowing stroke cycle can lead to a higher compensation resulting in an augmented effort, influencing sports performance, and increasing the risk of injury.
... According to literature, rowing on dynamic ergometers, or using "slides", can reduce the risk of injury (Bernstein, 2002;Thornton et al., 2017), but it is not possible to differentiate power delivery and coordination patterns based on ergometer design (Greene et al., 2013). Moreover, biomechanical and physiological parameters are reportedly discordant in rowing on stationary and dynamic ergometers (Benson, Abendroth, King, & Swensen, 2011;Holsgaard-Larsen & Jensen, 2010;Vinther et al., 2012). ...
... Kerhervé et al., 2018) and confirm the hypothesis of this study. Although peak force and peak power per stroke were previously reported to be greater on SE (Bernstein, 2002;Colloud, Bahuaud, Doriot, Champely, & Chèze, 2006), it likely attributable to the relatively lower force applied per each stroke and accompanying greater stroke frequency, which results in similar overall power outputs to that of DE. One of the limitations of this study is that we did not monitor the stroke rate, and therefore no conclusions can be drawn. ...
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It has been reported that ergometer design can elicit biomechanical alterations in terms of single stroke power, stroke frequency and stroke length, in rowing. However, detailed examination of the metabolic and physiological milieu in response to ergometer design changes is warranted. Thus, the purpose of the present study was to compare the effect of two different rowing ergometer setups during an incremental maximal test on metabolic parameters. The sample consisted of 12 national and international level male rowers. Two different versions of the Concept 2 model E ergometer were used, in a static setup without slides and in a dynamic setup with the slides. The following metabolic parameters were analyzed: power output, oxygen uptake, heart rate peak and at anaerobic threshold, minute ventilation, breathing frequency, and respiratory volume. No significant differences were found in any of the monitored parameters. This suggests that ergometer design does not affect metabolic parameters during an incremental test, highlighting that coaches and practitioners can likely employ any reasonable ergometer set-up, without hindering the performer.
... Vinther et al. [19] investigated 22 subjects belonging to the national team of Denmark, and reported that the handle peak force on the SLD was significantly smaller than on the FIX ergometer. Furthermore, some studies showed similar results on a dynamic ergometer of which the stretcher moves forward [3,20]. A previous study examined the handle peak force in beginners and male/female rowers using FIX and SLD Concept 2 ergometers, as adopted in this study, and reported that the handle peak force on the fixed ergometer was higher in both males and females [5]. ...
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OBJECTIVES This study compared the mechanical outputs and lower joint kinematics during rowing motion using fixed and slide-type rowing ergometers to clarify the slide type's characteristics.METHODS Junior rowers performed a simulated 2000m race pace under two ergometer conditions. Rowing motion was filmed by a high-speed video camera (200 fps) from right angles beside the subject and changes in Hip and knee joint angles were measured. Spatiotemporal parameters as well as force output from the handle and stretcher and joint angle kinematics at 500m spot calculated.RESULTS In the 2000m time trial, the two conditions showed no significant difference. However, significant differences were observed in the maximum stretcher force, with the slide-type rowing ergometer showing higher values than the fixed-type rowing ergometer. On the other hand, greater values in handle force were found for the fixed-type rowing ergometer than slide-type rowing ergometer greater. Greater rate of force development for the handle and stretcher were observed in the slide-type rowing ergometer condition. No significant differences were observed in angular changes between the two conditions, but knee and hip maximum angular accelerations were significantly higher in the slide-type rowing ergometer condition. Higher stretcher force in slide-type rowing ergometer at the beginning of the stroke is characterized as the influence of maximal angular acceleration in both knee and hip joint extensions, causing high rate of force development of handle and stretcher forces in the initial phase of the drive. As a result, the muscle groups including the biarticular muscles around hip and knee joints may work in coordination to exert significant force, a defining characteristic of the slide-type rowing ergometer.CONCLUSIONS The fix-type rowing can be used effectively to strengthen the maximum handle pull strength, mainly upper extremity. On the other hand, slide-type rowing can be used effectively to strengthen the maximum stretcher force as well as it’s rate of force development, which might be similar force output of lower extremity as performed during on-water rowing.
... Stroke rate, the only parameter that was higher on the DE at all seven stages during the incremental rowing test, aligns with previous literature (Bernstein et al. 2002;Benson et al. 2011;Rossi et al. 2015;Zahiran et al. 2019). ...
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Background: Stationary (SE) and dynamic (DE) rowing ergometers, that are utilized for indoor training and physical assessment of competitive rowers, may elicit different physiological and biomechanical responses. The present study used SE and DE ergometers to examine submaximal and peak physiological and biomechanical responses during an incremental rowing test. Methods: Twelve National Collegiate Athletic Association (NCAA) Division I oarswomen performed seven-stage rowing tests with the last stage performed with maximal effort. Heart rate (HR), lactate (LA), oxygen uptake (VO2), ventilation (VE), stroke rate (SR), gross efficiency (GE), and rating of perceived exertion (RPE) were obtained; while trunk, hip, knee, shoulder, and elbow ranges of motion (ROM) were measured. Results: SR was higher at maximal stage DE (29.3 vs. 34.8 strokes/min, p = 0.018, d = 1.213). No difference occurred in responses of maximal stage HR, RPE, VO2, VE, LA, or GE between the two ergometers. Submaximal LA and SR were greater on the DE for all submaximal stages. Submaximal VE was greater on the DE for all submaximal stages except Stage 3 (p = 0.160, d = 0.655). VO2 was higher on the DE Stages 2-5. GE was higher on the SE for Stages 2-5. Athletes showed increased trunk (p = 0.025, [Formula: see text] = 0.488) and knee (p = 0.004, [Formula: see text] = 0.668) ROM on SE. Conclusion: Rowing on the DE appears to elicit a greater stroke rate and more optimal joint angles especially at high intensities. Hence, the DE is worthy of consideration as a preferred ergometer for women rowers.
... No significant differences in mean HR response at Dmax (173 [7] vs 175 [6.8] beats·min −1 ) or in fractional HR at Dmax (88.3 [3] vs 89.5% [2.4%] of HRmax) were observed between conditions. As would be expected using a standard GXT protocol, HR increased with increasing load (F = 737, P < .001). ...
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Purpose: The purpose of the current study was to compare responses to graded exercise testing (GXT) on 2 popular commercial rowing ergometers. Methods: A cohort of 23 subelite male rowers (age 20 [2] y, height 1.88 [0.06] m, body mass 82.0 [8.8] kg) performed a GXT on both stationary (Concept2 [C2]) and dynamic (RowPerfect3 [RP3]) rowing ergometers. Physiological responses including oxygen consumption (VO2), heart rate (HR), blood lactate concentration (BLa), stroke rate (SR), and minute ventilation (VE) were recorded. BLa data were plotted graphically and anaerobic threshold was identified using the Dmax method. Workload, HR, and VO2 at Dmax were interpolated. Physiological responses at maximal exercise and at Dmax were compared, along with response across a discrete range of submaximal workloads. Results: At maximal exercise, no significant differences in HR, VO2, or BLa were observed (P > .05); however, VEpeak was significantly higher during RP3 tests (T = 2.943, P < .05). No significant differences in HR, VO2, or BLa at Dmax were observed (P > .05). When comparing across submaximal workloads, HR was significantly higher with the RP3 at 2 distinct workloads (210 and 240 W; P < .05), while SR was higher during RP3 testing at all workloads (F = 56.7, P < .05). When SR was fixed as a covariate, the effect of ergometer on HR response was not significant. A significant workload by ergometer interaction effect was observed for SR with higher data recorded on the RP3 (F = 3.48, P < .01). Levels of agreement for GXT-derived measures of anaerobic threshold (Dmax) were deemed unacceptable. Conclusions: These results indicate that while some differences in HR and VE response were observed between ergometers, these differences were a result of SR alterations between ergometer type. While no differences in response at Dmax were observed, the poor levels of agreement between ergometers suggests that prescription of GXT-derived threshold for training should ideally be specific to the rowing ergometer upon which the test was performed.
... Regular interval sessions for training at the intercollegiate level average over 60 minutes on the ergometer. Coaches often focus on both increasing the length of the stroke and greater force, which creates a greater risk of damage to soft tissues in the back(Bernstein, Webber, & Woledge, 2002). ...
... Dynamic ergometer consists of two sliders that were mounted underneath a stationary ergometer. Several authors have previously showed that rowing on dynamic ergometer may better simulate movement patterns associated with onwater rowing (Bernstein et al., 2002;Colloud et al., 2006;Elliott et al., 2002). Furthermore, similar physiological (e.g. ...
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Rowing involves cyclic motions that have a number of similar repetitions of joint excursion. Similar movement patterns, physiological, muscular activity and biomechanical aspects were observed while rowing on dynamic ergometer and on water. The purpose of our study is to evaluate the changes of lower limb kinematics during 2000m rowing on dynamic ergometer among male junior national rowers. Ten male junior national level rowers participated in the study. 24 passive reflective markers were attached on their lower extremity and their rowing motions were captured. Each phases of rowing cycle was interpolated to 100 time points separately. The lower limb joint kinematics were compared across every 500m sections to evaluate its changes during 2000m rowing trial. There was a statistically significant difference between stroke rates for every 500m of 2000m rowing trial as determined by one-way ANOVA (F(3,36) = 4.880, p = 0.006). Kinematical variabilities were observed across splits particularly in frontal and transverse planes of lower limb joints.
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Aim To report the epidemiology of injury and illness in elite rowers over eight seasons (two Olympiads). Methods All athletes selected to the Australian Rowing Team between 2009 and 2016 were monitored prospectively under surveillance for injury and illness. The incidence and burden of injury and illness were calculated per 1000 athlete days (ADs). The body area, mechanism and type of all injuries were recorded and followed until the resumption of full training. We used interrupted time series analyses to examine the association between fixed and dynamic ergometer testing on rowers’ injury rates. Time lost from illness was also recorded. Results All 153 rowers selected over eight seasons were observed for 48 611 AD. 270 injuries occurred with an incidence of 4.1–6.4 injuries per 1000 AD. Training days lost totalled 4522 (9.2% AD). The most frequent area injured was the lumbar region (84 cases, 1.7% AD) but the greatest burden was from chest wall injuries (64 cases, 2.6% AD.) Overuse injuries (n=224, 83%) were more frequent than acute injuries (n=42, 15%). The most common activity at the time of injury was on-water rowing training (n=191, 68). Female rowers were at 1.4 times the relative risk of chest wall injuries than male rowers; they had half the relative risk of lumbar injuries of male rowers. The implementation of a dynamic ergometers testing policy (Concept II on sliders) was positively associated with a lower incidence and burden of low back injury compared with fixed ergometers (Concept II). Illness accounted for the greatest number of case presentations (128, 32.2% cases, 1.2% AD). Conclusions Chest wall and lumbar injuries caused training time loss. Policy decisions regarding ergometer testing modality were associated with lumbar injury rates. As in many sports, illness burden has been under-recognised in elite Australian rowers.
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The purpose of this study was to quantify and contrast the instantaneous segmental and total body energy patterns of rowing a single scull racing shell with rowing a Gjessing (Norway) rowing ergometer (RE), and to contrast energy savings through exchanges of mechanical energy among segments and conversions of energy within segments. Four scullers, two male and two female, were filmed at three stroke rates while rowing on a stationary and a wheeled RE, and rowing in single sculls racing shells. Coordinates of joint markers were digitized, digitally filtered, and combined with estimated body segment parameters using link-segment mechanics to obtain segmental centre of gravity kinematics. Mechanical energy and internal work analyses were conducted to compute the energy savings due to exchange and interconversion of segmental energy. The internal work was least in the wheeled RE and greatest in the boat. Savings of energy through exchanges were greatest in the boat, and least in the stationary RE. Savings of energy through interconversion were greatest in the wheeled RE. The interconversions (expressed as a percentage of total work) were quite similar for both the boat and the stationary RE. The additional energy savings with the wheeled RE allow the conclusion that wheeled RE testing will permit athletes to work at stroke rates similar to racing levels.
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Recordings of force developed simultaneously by four rowers in a good club-standard eight over a 20-min training run were analysed in terms of mean and variability. The average force-time profiles showed small but distinctive differences between rowers that were maintained as force declined through the run. The variability was examined further in terms of time-series of features extracted from single force-time profiles, including the peak force, duration and interstroke interval. There were consistent positive correlations between rowers in interstroke intervals even after removal of low-periodicity components (trends) in the time-series.
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