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Original Research
The Effects of Elliptical Cross Training on VO
2max in Recently
Trained Runners
DUSTIN P. JOUBERT1†, GARY L. ODEN2, & BRENT C. ESTES2
1Texas A&M University; Department of Health and Kinesiology; 2Sam Houston
State University; Department of Health and Kinesiology
†Denotes graduate student author, ‡Denotes professional author
ABSTRACT
Int J Exerc Sci 4(1) : 4-12, 2011. This study examined the effects of elliptical cross training on
VO2max in recently trained runners. 12 female and 8 male participants (mean ± SD; age = 23.70 ±
6.33 years, body mass index = 24.85 ± 5.89 kg/m2) completed an initial four-week run training
program, exercising four days/week, 30 minutes/day, at 80% maximal heart rate. VO2max was
predicted based on the duration of a Bruce graded-maximal treadmill test (GXT) prior to and
after the run training. After initial training phase and post-test, subjects volunteered for the
detrain group (n = 6) or were assigned to the run (n = 7) or elliptical (n = 7) based on a matched-
pair design. Elliptical and run groups exercised three weeks under same prescription as initial
program. GXT again performed after mode-specific training phase. VO2max (ml/kg/min)
increased (p < 0.001) from the pre-training (39.89 ± 10.74) to post-training (41.66 ± 10.90) after the
initial run training program. Although not statistically significant, VO2max declined (0.8%
running, 1.5% elliptical, and 4.8% detraining) for all groups following the additional mode-
specific program. Despite declines, repeated measures ANOVA showed no significant
differences within or between groups before and after the mode-specific training phase.
However, dependent sample t-test did reveal a decline (p < 0.05) in GXT time (minutes) for the
detrain group from before (11.01 ± 2.80) and after (10.54 ± 2.72) their detrain phase. Future
research should determine if elliptical exercise maintains VO2max when away from running for
longer periods.
KEY WORDS: Elliptical, VO2max, Run, Cross Train
INTRODUCTION
The risks and incidence of injuries due to
distance running have been well
established (13, 16, 20). Research indicates
that overuse is the most common cause of
running injury (26). Many injuries, such as
stress fractures, may prevent an individual
from running until completely recovered.
Because a decline in physiological fitness
and running performance will occur in the
absence of running, cross training exercise
is an option to attempt to maintain fitness
while injured (8, 15). While different
modes of cardiovascular exercise have been
compared to running in the past, little
research exists on the benefits of an
elliptical exercise training program.
Elliptical exercise machines provide an
upright, non-impact, weight bearing form
of aerobic exercise, similar to the running
motion, as the lower body moves in a
smooth, elliptical path on a set track (2).
Elliptical Cross-Training in Runners
International Journal of Exercise Science 5 http://www.intjexersci.com
The impact forces on the lower extremity,
while elliptical training, were found to be
equivalent to walking and less than half
that of running (23). The low impact forces
of elliptical exercise may make it a feasible
training option for many running injuries.
Several studies (2, 3, 5, 6, 7, 11, 12, 21, 23, 24,
25, 27) have looked at the effects of an
individual bout of elliptical exercise
compared to treadmill running, but few
studies (9) have looked at elliptical exercise
as part of an actual training program.
Cardiorespiratory endurance, determined
by an individual’s maximum ability to
consume oxygen (VO2max), is a significant
health component to fitness because it is
inversely related to premature death (17).
Additionally, a high VO2max increases
physical work capacity or the ability to
produce a large quantity of energy over a
prolonged period of time. Furthermore,
VO2max is significantly correlated with
running performance, especially in
heterogeneous groups of people (18). The
purpose of this study was to determine the
effectiveness of an elliptical exercise-
training program in maintaining
cardiorespiratory fitness, particularly
VO2max, in recently trained runners.
It was hypothesized that an initial 4-week
run-training program would significantly
improve VO2max in the first phase of the
study. In the second 3-week phase of
training, the elliptical and run training
groups were expected to maintain or
improve fitness in an equivalent manner,
while a detraining group was expected to
show a decline in fitness. This study
furthered the knowledge base on the
cardiorespiratory benefits of elliptical cross
training exercise by determining the ability
of elliptical training to sustain or improve
maximal oxygen consumption in recently
trained runners. These findings can be
applied to healthy adults attempting to
improve cardiorespiratory fitness, as well
as beginning runners attempting to
maintain or improve fitness through a
cross-training program.
METHODS
Subjects
Twelve female and 8 male participants
(mean ± SD; age = 23.70 ± 6.33 years, height
= 1.71 ± .10 m, weight = 74.8.86 ± 20.34 kg,
body mass index = 24.85 ± 5.89 kg/m2,
percent body fat = 21.37 ± 11.02%)
completed all training and testing
requirements. Subjects were recruited from
kinesiology classes and the recreational
sports facility at a regional university in the
southwest. All subjects participated on a
completely voluntary basis, and students
from kinesiology classes were not offered
class credit or extra credit for participation
in the study. Qualified participants
included individuals with access to the
Recreational Sports Facility that also met
ACSM guidelines for low risk, apparently
healthy individuals (1). Participants
completed a study application that
RESULTS
Phase I
Results of the pre-test measurements and the first post-test (four weeks) for the group as a
whole are presented in Table 1. VO2max was predicted based on total time (minutes) during
the Bruce Protocol treadmill test (4). The following equation from (10) was used to predict
VO2max: VO2max = 14.76 - 1.38 (time) + 0.451 (time)2 - 0.012 (time)3. There were significant
improvements (p ! 0.001) between the initial and Post-Test I assessments for both the duration
of the Bruce treadmill test and for predicted VO2max, which confirmed the researcher’s
hypothesis. VO2max changes from Pre-Test to Post-Test I are also presented in Figure 1.
Table 1
Phase I Testing Characteristics
Data shown as Mean ± SD.
* p value ! 0.001 between Pre-Test and Post-Test I
Summary details of the initial four week run training phase are shown in Table 2. Subjects
were required to complete at least 75% (12 of 16) of the prescribed runs over the four week
period in order to advance to the post-test and second phase of training.
Table 1. Physical Testing Characteristics
(n = 20)
Pre-Test
Post-Test I
Weight (kg)
74.80 ± 20.34
74.55 ± 20.25
BMI (kg/m2)
24.85 ± 5.89
24.85 ± 5.97
Body Fat (%)
21.37 ± 11.02
20.66 ± 11.95
Bruce (min)
11.32 ± 2.69*
11.77 ± 2.69*
VO2
(ml/kg/min)
39.89 ± 10.74*
41.66 ± 10.90*
Max HR (bpm)
189.75 ± 9.00
190.30 ± 8.43
Elliptical Cross-Training in Runners
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identified their current activity level and
training availability. Subjects also
completed a Physical Activity Readiness
Questionnaire (PAR-Q), AHA/ACSM
Health/Fitness Facility Pre-participation
Screening Questionnaire, and signed an
informed consent form. The study protocol
was approved by the Protection of Human
Subjects Committee at the University where
the data was collected.
Testing Protocol
After subject selection, pre-testing included
an initial body composition assessment
with the BodPod (Life Measures Inc.,
Concord, CA). Additionally,
cardiorespiratory endurance was evaluated
with a graded maximal exercise test on a
Quinton Treadmill (Cardiac Science Corp.,
Hannover, Germany) using the Bruce
Protocol (4). All subjects attained a
maximal heart rate within ten beats of their
age predicted maximum to meet criteria for
maximal volitional exhaustion. Due to
malfunctions with the lab’s metabolic cart
at the time of the study, maximal oxygen
consumption was estimated from the
duration of the Bruce test by using the
following predictive equation by Foster et
al. (10): VO2max = 14.76 - 1.38 (time) + 0.451
(time)2 - 0.012 (time)3. This was a
generalized equation that was developed
for use in cardiac patients as well as
healthy, sedentary and active individuals,
making it a good match for subjects in the
present study. This equation was
previously shown to have a correlation
coefficient of 0.97 when compared with
direct measurement of VO2max (10).
Additionally, maximal heart rate (Sigma
Sport PC-14 Heart Rate Monitor: Sigma
Sport USA, Batavia, IL) and total time were
recorded from the maximal exercise tests.
This testing protocol was repeated after
four and seven weeks. Subjects were given
24-72 hours for recovery following their last
training session prior to subsequent tests;
however, there were no further controls on
recovery within this given time range.
Training Protocol
The initial training phase lasted four weeks,
and all subjects were directed to exercise at
the same target training frequencies,
relative intensities, and durations while
running on a Precor 932i Series Treadmills
(Precor Inc., Woodinville, WA). The
training program consisted of 30 minutes of
running for 4 days per week at an average
intensity of 80% the maximal heart rate
achieved during the initial Bruce test. Heart
rate monitors were used to record the
average heart rate for each training session
over the 30-minute workout. Following
each exercise bout, subjects recorded their
average heart rate and the duration of the
session, along with the distance ran.
Successful completion of the initial four
week running program required the
subjects to complete at least 75% of the
prescribed workouts, which corresponded
to at least 3 runs/week and 12 runs over the
entire training phase. An increased
frequency of weekly training sessions
improves VO2max, but there is a plateau in
these gains beyond 3 days per week (22).
For this reason, and in order to maximize
the sample, subjects that completed 3-4
sessions per week were included. Subjects
who did not complete 75% of the required
workouts were dropped from the study.
After subjects completed the initial four
week running program, VO2max and body
composition were again assessed using the
same protocol as the pre-test. Subjects were
then placed into one of three training
groups (run, elliptical, detrain) for the
Elliptical Cross-Training in Runners
International Journal of Exercise Science 7 http://www.intjexersci.com
remainder of the study. Subjects
volunteered to be in the detraining group (n
= 6), while the remaining subjects were
assigned to the elliptical (n = 7) and
running (n = 7) groups based on a match
pair design. Subjects who were to be
assigned to the run or elliptical groups
were ranked from highest VO2max to the
lowest, and every two individuals down
the list were randomly assigned to either
the elliptical or run group. All elliptical
training was performed on Octane Pro4500
Ellipticals (Octane Fitness, Brooklyn Park,
MN). The elliptical and run training groups
continued to exercise for an additional
three weeks at the same frequency (four
days/week), relative intensity (80%
maximum heart rate), and duration (30
minutes). The third group ceased all aerobic
exercise training to serve as a sedentary
control and demonstrate the effects of
detraining. Following this second phase of
training, all subjects completed a final
assessment of VO2max and body
composition using the protocol performed
during the pre-test and mid-test.
Statistical Analysis
Means and standard deviations for subjects’
height, weight, body mass index, body fat
percentage, age, duration of maximal Bruce
Protocol test, predicted VO2max, and
maximum heart rate were reported for the
pre-test and at four, and at seven weeks.
After the initial phase of run training,
pretest values for weight, body mass index,
body fat percentage, duration of maximal
Bruce Protocol test, predicted VO2max, and
maximum heart rate were compared to the
four week assessment using a t-test for
dependent samples. A p-value equal to or
less than 0.05 was accepted as significant.
These same values were compared within
training groups (running, elliptical, and
detraining) between the four week and
seven week assessments. Between groups
comparisons for the four week and seven
week assessments were made using
repeated measures analysis of variance
(MANOVA). Average number of workouts
for each training phase, relative heart rate
intensities, duration, distance run, and
running pace were reported for both phases
of training. In the final three week training
phase, these workout variables were
compared between the elliptical and
running groups using a t-test for
independent samples. All statistical
analyses were performed with the
Statistical Package for the Social Sciences
version 15.0 (SPSS Inc., Chicago, IL).
RESULTS
Phase I
Results of the pre-test measurements and
the first post-test (four weeks) for the group
as a whole are presented in Table 1.
VO2max was predicted based on total time
(minutes) during the Bruce Protocol
treadmill test (4). The following equation
from (10) was used to predict VO2max:
Summary details of the initial four week run training phase are shown in Table 2.
Subjects were required to complete at least 75% (12 of 16) of the prescribed runs
over the four week period in order to advance to the post-test and second phase
of training.
Table 2
Table 2. Phase I Training Characteristics
Note. Data shown as Mean ± SD.
Phase II
A comparison of Post-Test I and Post-Test II is provided in Table 3.
Following the three week phase of the mode specific training, there was a decline
in VO2max of 0.8%, 1.5% and 4.8% for the run, elliptical, and detraining groups,
respectively. A t-test for dependent samples for each group did not reveal any
significant changes, although the decline in predicted VO2max for the detraining
(n = 20)
Mean ± SD
Total Runs
13.80 ± 1.47
Duration (min)
29.91 ± 0.40
% Max HR
82.75 ± 4.23
Distance (miles)
2.64 ± 0.58
Pace (min/mile)
11.84 ± 2.59
Pace (miles/hr)
5.30 ± 1.13
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VO2max = 14.76 - 1.38 (time) + 0.451 (time)2
- 0.012 (time)3. There were significant
improvements (p ≤ 0.001) between the
initial and Post-Test I assessments for both
the duration of the Bruce treadmill test and
for predicted VO2max, which confirmed the
researcher’s hypothesis. VO2max changes
from Pre-Test to Post-Test I are also
presented in Figure 1.
Summary details of the initial four week
run training phase are shown in Table 2.
Subjects were required to complete at least
75% (12 of 16) of the prescribed runs over
the four week period in order to advance to
the post-test and second phase of training.
Phase II
A comparison of Post-Test I and Post-Test II
is provided in Table 3. Following the three
week phase of the mode specific training,
there was a decline in VO2max of 0.8%,
1.5% and 4.8% for the run, elliptical, and
detraining groups, respectively. A t-test for
dependent samples for each group did not
reveal any significant changes, although the
decline in predicted VO2max for the
detraining group demonstrated a trend
towards significance (p = 0.056). There was
a significant decline in Bruce treadmill time
for the detraining group (p = 0.045).
A repeated measures ANOVA was used to
analyze the change in means between Post-
Test I and Post-Test II variables among the
elliptical, run, and detraining groups.
Thus, Post-Test I VO2max to Post-Test II
VO2max was used as a within subjects
factor and mode of exercise was used as the
between subjects factor. When comparing
changes in VO2max between the three
modes, the repeated measures ANOVA
found no significant differences (p = 0.296,
df = 2, F = 1.307). The changes in VO2max
between Post-Test I and Post-Test II for
each group are displayed in Figure 2.
Table 3. Comparison of Post-Test I and Post-Test II
Run (n = 7)
Elliptical (n = 7)
Detrain (n = 6)
PT-I
PT-II
PT-I
PT-II
PT-I
PT-II
BMI (kg/m2)
25.57
± 6.95
25.43
±6.60
23.57
± 3.15
23.57
± 3.15
25.50
± 7.87
25.33
± 7.87
Body Fat (%)
21.33
± 11.10
22.34
± 11.42
16.27
± 10.20
17.62
± 10.24
24.98
± 14.84
22.32
± 13.80
Bruce (min)
11.52
± 2.83
11.46
± 2.59
12.66
± 2.63
12.49
± 2.48
11.01*
± 2.80
10.54*
± 2.72
VO2(ml/kg/min)
40.67
± 11.50
40.34
± 10.66
45.17
± 10.89
44.50
± 10.36
38.70
± 11.02
36.82
± 10.47
Max HR (bpm)
191.57
± 9.43
191.57
± 9.24
185.71
± 6.26
183.00
± 7.48
194.17
± 8.16
195.17
± 8.11
Note. Data shown as Mean ± SD.
PT-I (Post-Test I), PT-II (Post-Test II), * p value ! 0.05 within group.
A summary of Training Phase II is provided in Table 4. Subjects in the training
groups were required to complete at least 80% (10 of 12) of the prescribed
workouts. There were no significant differences in training frequency, intensity,
or duration between the elliptical and run groups when analyzed with a t-test for
independent samples.
*p value < 0.001 between Pre-test and Post-Test 1
Summary details of the initial four week run training phase are shown in
Table 2. Subjects were required to complete at least 75% (12 of 16) of the
prescribed runs over the four week period in order to advance to the post-test
and second phase of training.
Figure 1. Mean VO2max (± SD) before and after 4 weeks run
training (n = 20).
± 11.50
Max HR (bpm)
191.57
± 9.43
191.57
± 9.24
185.71
± 6.26
183.00
± 7.48
194.17
± 8.16
195.17
± 8.11
Note. Data shown as Mean ± SD.
PT-I (Post-Test I), PT-II (Post-Test II), * p value ! 0.05 within group.
A summary of Training Phase II is provided in Table 4. Subjects in the training
groups were required to complete at least 80% (10 of 12) of the prescribed
workouts. There were no significant differences in training frequency, intensity,
or duration between the elliptical and run groups when analyzed with a t-test for
independent samples.
Figure 2. Mean VO2max (± SD) in recently-trained runners
before and after 3 weeks additional training.
Elliptical Cross-Training in Runners
International Journal of Exercise Science 9 http://www.intjexersci.com
Tukey’s Post-Hoc test also found no
significant differences among one mode to
any other for any of the measured
variables. In summary, there was a
significant decline in the Bruce treadmill
time for the detraining group only.
However, when comparing all three modes
for each repeated measure variable in Post-
Test I and Post-Test II, there were no
significant differences found, which
contradicted the researchers’ initial
hypothesis.
A summary of Training Phase II is
provided in Table 4. Subjects in the
training groups were required to complete
at least 80% (10 of 12) of the prescribed
workouts. There were no significant
differences in training frequency, intensity,
or duration between the elliptical and run
groups when analyzed with a t-test for
independent samples.
DISCUSSION
This study analyzed the effectiveness of an
elliptical exercise-training program in
maintaining cardiorespiratory fitness,
particularly VO2max, in recently-trained
runners. The design of this training study
intended to provide initial improvements in
VO2max for all subjects through a four
week training program with a common
modality (running). This allowed for
application of the present study to beginner
runners. The changes in cardiorespiratory
fitness, following mode specific exercise
(run, elliptical, detrain), were then analyzed
in phase two of the study.
The initial four week training phase did
yield significant improvements in VO2max.
Other training studies (9) comparing
elliptical and running modes of training fail
to account for the expected initial
improvements in cardiorespiratory fitness
that might occur with any aerobic training
program that is recently introduced to a
relatively sedentary group, regardless of
modality. The present study accounted for
this initial training stimulus by requiring all
subjects to begin a run training program
prior to comparing separate modes. This
design allows for analysis of the ability to
maintain or further improve fitness through
various modes of training.
Phase two of the training resulted in no
significant differences between the changes
in VO2max, or any other variable, across the
three training groups from Post-Test I to
Post-Test II. The detraining group did
show a larger decline in VO2max (4.8 %)
compared to the running group (0.8%) and
elliptical group (1.5%). While all groups
declined in VO2max, only the decline of the
detraining group neared significant values
(p = 0.056). These changes were expected
based on previous detraining research by
(14). As a whole, the repeated measures
ANOVA yielded no significant changes in
VO2max due to mode of exercise. Given
the PT-I VO2max values, there were some
concerns that the groups being compared
were not identical. Despite the matched-
pair design in assigning the elliptical and
running groups, the elliptical group
appeared to have a higher VO2max (45.17
ml/kg/min) compared to the running
group (40.67 ml/kg/min) and detraining
Table 4. Phase II Training Characteristics
Run Group (n = 7)
Elliptical Group (n = 7)
Total Workouts
10.71 ± 1.11
10.71 ± 1.70
Avg. Duration (min)
29.44 ± 1.17
30.00 ± 0.00
% Max Heart Rate
81.05 ± 2.26
79.77 ± 5.30
Note. Data shown as Mean ± SD.
Elliptical Cross-Training in Runners
International Journal of Exercise Science 10 http://www.intjexersci.com
group (38.70 ml/kg/min). A one-way
ANOVA comparing the PT-I VO2max
values across groups was not significant (p
= 0.57). Because all subjects underwent the
same initial run training stimulus and were
not significantly different at PT-I, the
analysis for the second phase of training
was carried out. With that said, more
evenly matched groups and a larger sample
(power analysis was not performed) might
have led to significant findings at PT-II
between groups. Nonetheless, an
attenuation in the decline in VO2max from
4.8% (detrain) to 1.5% (elliptical), still may
have practical value for an injured runner
hoping to maintain cardiovascular fitness
through cross training.
Furthermore, it is likely that the changes
from PT-I to PT-II would be more severe
had the second phase of training lasted
longer than three weeks. Ideally, each
training phase would have lasted at least
six weeks. The time constraints given the
conclusion of the spring semester and
inability to recruit subjects that would be
available during summer break were a
significant limitation to the current study.
Future research can provide more clear
results by improving on this and previously
stated design flaws. However, the
researchers believe the two training phase
design, which includes an initial run phase,
employed in the present study is a good
model in order to make comparisons
between alternate aerobic training
modalities for application to injured
runners.
When comparing the intensity of the
second phase of training, the elliptical
group exercised on average at 79.77% ±
5.30% of max heart rate and the running
group at 81.05% ± 2.26%. While this was
not a significant difference, there were
anecdotal reports from the subjects in the
elliptical group regarding the difficulty in
attaining the target heart rate. Exercise
prescription for both the elliptical and run
groups was based on the subject’s maximal
heart rate achieved during a treadmill GXT,
but maximal oxygen consumption and
heart rate have been shown to be equal for
treadmill and elliptical exercise (6, 7, 27).
Looking specifically at rating of perceived
exertion (RPE), some studies have shown
equal RPE (21, 23) values for running and
elliptical exercise at a given intensity, while
others showed lower RPE (2, 12, 5) or
higher RPE (25, 3) for a given intensity.
This ambiguity is somewhat clearer when
the distinction is made between whole
body RPE and lower body RPE, in which
case overall RPE was equivalent, but leg
RPE was greater for the elliptical (11). In the
present study, subjects exercising on the
elliptical were directed to alter the cadence
and resistance as they wished to attain the
target heart rate. Subjects were also
directed to move only in the forward
direction. RPE was not measured in the
current study and not believed to affect the
results since both groups worked out at the
same heart rate intensities relative to their
treadmill maximum.
Runners who are injured or limited from
running need alternative training options in
order to maintain fitness. Cross training
modalities such as cycling have been
previously explored, but elliptical exercise
is relatively new and less investigated,
especially in terms of the chronic training
effects. Simply by viewing the motions of
elliptical, cycling, and running exercise, it
seems that the elliptical motion may be
more specific to running than is cycling.
Whether or not this is true would require
Elliptical Cross-Training in Runners
International Journal of Exercise Science 11 http://www.intjexersci.com
more measures than just VO2max, but also
need to look at other performance variables
such as lactate threshold, running economy,
and peak treadmill running velocity (19).
However, given the present findings,
elliptical exercise may be a viable cross
training option for recently-trained runners
attempting to maintain VO2max in the short
term. Studies comparing more
physiological and performance measures
for multiple cross training modalities can
shed more light on which mode of training
might be best for an injured runner.
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