JOURNALOF
Vol.
APPLIED
PHYSIOLOGY 1975.
39, No. 3, September
Maximal
Printed
in U.S.A.
oxygen
and running
uptake
during
at various
BRYANT A. STAMFORD Exercise Physiology Laboratory,
state
RESEARCH
for
the
of training;
LITERATURE
assessment
of
locomotor
speed
is replete maximum
with oxygen
University of Louisville,
measures uptake
three males,
2 max
(8)
Kentucky 40208
participating 2) highly
trained walkers.
(running
experimental trained (running)
and
race
groups: males,
walking)
I)
average
fit
and 3) highly competitive race
METHODS
A total of 19 male undergraduate and graduate students and faculty members at the University of Louisville volunteered follows:
as
subjects
(Table
1).
Subjects
were
grouped
as
group I (N = 12) was composed of individuals who were not currently involved in a cardiovascular endurance training program nor had they been trained previously. Group I members were considered of average fitness (AF). Group II (N = 7) was composed of individuals currently involved in cardiovascular endurance training for the purpose of maintaining previously induced fitness levels. Five of the subjects comprising Group II were former track (middle distance) and/or cross country runners. Group II members were considered of high fitness (HF). An additional group, group III, composed of highly fit competitive race walkers (CRW, N = 3) were selected from the greater Louisville area. Subjects assigned to group I each performed a total of six maximal performance tests. All subjects were familiarized with treadmill walking and running prior to performance of their first test. Tests were randomly assigned thus avoiding an ordered pattern in the testing schedule. With the exception of a modified Balke walking test, all tests were discontinuous in nature. Preceding the Balke test (and all other maximal performance tests) was a lo-min warm-up consisting of walking at 3.5 mph on a 10 % grade. The warm-up was followed by a 5-min rest period. The Balke test was performed at a constant walking speed of 3.5 mph. Subjects began walking at a 10 % grade which was subsequently elevated 2.5 % every 2 min. Testing was terminated voluntarily by the subject. Throughout all tests subjects were verbally encouraged to perform to maximal limits. Expired air was collected for each succeeding minute following a heart rate of 180 beats/min. The remaining five Vo2 max tests were performed at speeds of 4.5, 5.5, 7.0, and 8.5 mph. Testing at 4.5 mph
proposed (002
Louisville,
The purpose of the present study was to compare 002 lnax and associated physiological responses elicited during treadmill walking and running at a variety of locomotor speeds. In addition the effects of state of training were examined as comparisons of the aforementioned tests were made within
max).
Among the most widely accepted measures are cycling on a stationary bicycle ergometer and walking and running on a motor-driven treadmill. vo2 max has been found to be consistently higher during treadmill (walking or running) performance compared with cycling (4-7). Treadmill performance is thought to elicit greater X702 max levels because of a larger working muscle mass (3). Comparisons of I702 max elicited during walking versus running are not consistent. Newton (9) reported similar 002 mav levels for the Balke walking test and a constant load running test. McArdle et al. (8) observed that the Balke walking test resulted in significantly lower i/102 max levels when compared to running tests. The same authors (8) suggest that local discomfort in the lower back and calf muscles may limit performance. It has been further suggested that a walking speed greater than that typically utilized in the Balke test (3.5 mph) may reduce muscular discomfort as grade elevations would be reduced, thus resulting in an increased VO
walking
speeds
STAMFORD, BRYANT A. Maximal oxygen uptake during treadmill walking and running at various speeds. J. Appl. Physiol. 39(3): 386389. 1975.-Three groups of male subjects, average fitness (AF, N = 1 Z), high fitness (HF, N = 7) and highly fit competitive race walkers (CRW, N = 3) performed maximal treadmill tests walking at 3.5 and 4.5 mph and running at 4.5, 5.5, 7.0, and 8.5 mph. In addition, the HF group performed a running test at 10.0 mph and the CRW group performed a walking test at 5.5 mph. All maximal oxygen uptake (vo, max> tests with the exception of the 3.5 mph walking test (modified Balke test) were discontinuous in nature. i’oz max obtained from walking tests was similar regardless of speed within each group. Walking voz max was significantly lower than running VOW max which was found to be similar over a speed range of 4.5 to 8.5 mph in the AF group. Running at 4.5 mph (HF group) and 4.5 and 5.5 mph (CRW group) resulted in lower Vo2 max levels than running at speeds 2 7.0 mph. Associated physiological variables (heart rate, ventilation, and respiratory exchange ratio) did not demonstrate a discernable pattern with reference to mode of locomotion (walking versus running) or speed. It was concluded that \ioz max elicited during walking is independent of speed and less than VOW Inax obtained during running. Running VOW max was interrelated with speed of running and state of training.
VO 2 maxi
treadmill
l
386
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vQ2
max
9
WALKING
VS.
RUNNING,
VARIOUS
SPEEDS
387
I. Personal data of subjects in groups 1, I., and I.1
TABLE Group
I II III Values
N
12 7 3
Age, yr 25.1 23.3 20.6
are means
zt 2.7 zt 0.4 & 1.4
Height,
177.3 175.4 177.8
cm
=t 3.6 AZ 3.2 AZ 3.7
Weight,
80.7 67.1 64.9
tested. At 7.0 mph, mean 002 max (ml kg-’ min-l) for the AF group was 48.96, 65.42 for the HF group, and 68.40 for the CRW group. These findings agree with Astrand’s classification of average and highly fit individuals (1). Mean Vo 2 Max for AF subjects (Table 2) was similar for walking tests at 3.5 and 4.5 mph and significantly lower (approx 6 %) than results of running tests which were also similar over a range of 4.5-8.5 mph. Max HR, \j~, and R were highest (not significantly) during the 3.5 mph walking test. Warm-up HR levels revealed an expected consistency among all tests. If an improved fitness level was achieved, the effects were likely balanced by random test scheduling. The highest grade elevation obtained during each test was inversely related to speed with the exception that running at 4.5 mph was performed to higher levels than walking at the same speed. VOW max and associated physiological measures for HF subjects (Table 3) were qualitatively similar to those obtained for AF subjects with the exception that walking at 3.5 mph and walking and running at 4.5 mph were not significantly different. Running speeds ranging from 5.5 to 10.0 mph resulted in similar VOW max levels. VOW lnax results obtained for CRW subjects (Table 4) were similar for walking speeds of 3.5, 4.5, and 5.5 mph. An increase (not significant) in Vo 2 max was noted for running speeds of 4.5 and 5.5 mph. CRW subjects demonstrated a significant increase in V02 max during running at 7.0 and 8.5 mph compared with results obtained during walking. Maximal grade elevation attained demonstrated a similar pattern in HF and CRW subjects as was described for AF subjects. In each of the three groups tested, there was no discernible pattern in max HR, R, or VE with reference to walking versus running or speed. Warm-up HR was progressively reduced from AF to HF to CRW subjects as fitness level increased. l
kg
=t 4.9 zt 3.0 zt 2.8
A SD.
included both walking and running. The term running was utilized for all performances whereby there was no period in which both feet were in contact with the running surface at one time. It is obvious that at reduced speeds of 4.5 and 5.5 mph, individuals were jogging rather than running. However, the term running, as described, encompasses both jogging and running and therefore was preferred for consistency. It sh .ould be noted that there was absolu tely no problem encountered in having subjects maintain a running pattern at reduced speeds. Tests conducted at 4.5 and 5.5 mph were initiated at a grade of 5 % and tests at 7.0 and 8.5 mph were initiated at 0%. Work bouts of 3-min duration were alternated with lo-min rest periods. Work bouts of 3 min have been shown to be effective for the attainment of 002 max at highintensity work (2, IO). Grade elevation was increased 2.5 % for each successive bout and expired air was collected during each of the final 2 min of work. This procedure continued until subjects were unable to complete a given 3-min work bout. Group II subjects performed each of the aforementioned tests plus an additional running test at 10.0 mph. Likewise, an additional test (walking) was performed by group 111 subjects at 5.5 mph. Tests conducted at 4.5 and 5.5 mph for groups II and 11. subjects were initiated at 10 %. Tests conducted at 7.0, 8.5, and 10.0 mph were initiated at 5 %, 2.5 %, and 0 %, respectively. All tests were conducted at the same time of day for each subject and separated by a minimum of 48 h. Pretest protocol was emphasized and included reporting to the laboratory in a well rested condition a minimum of 2 h following the intake of food. During exercise, expired air was collected in meteorological balloons as subjects breathed through a Collin’s triple-J valve. Ventilatory volume (VE) was determined on a Parkinson-Cowan dry gasmeter. Air samples were drawn in Z-liter bags and immediately analyzed for 02 and CO2 concentration by means of Beckman Es and LB-Z analyzers. Gas analyzers were regularly calibrated with known concentrations of standardized gases. Heart rate (HR) was recorded electrocardiographically during the final 15 s of each gas collection minute. data included an analysis Statistical analysis of obtained of variance for repeated measures and the Scheffe post hoc tests. Statistical significance was established at the 0.05 level. RESULTS
Tables 2-4 present mean values & standard deviations max HR, maximum respiratory exchange for Vo max (STPD), ratio (R), max VE (BTPS), maximum grade elevation atHR. There were tained for a given test, and warm-up significant differences in fitness among the three groups
DISCUSSION
The modified Balke test elicited significantly lower 2 max levels than running tests performed by the AF, HF, and CRW groups. These results are in agreement with those reported by McArdle et al. (8). The same authors (8) suggest that local discomfort in the lower back and calf muscles may limit performance and that perhaps a faster walking speed may alleviate this problem. Results obtained in the present study indicate that increasing the speed of walking from 3.5 to 4.5 mph does not increase VOW nlax (nor does it appear to alleviate muscular discomfort). Subjects repeatedly expressed complaints concerning the discomfort associated with the 4.5 mph walking test. Overwhelmingly, this test was considered the least preferable of all tests performed. The lower Vo 2 max associated with walking compared to running may be attributable to either the excessive grade elevations encountered or the act of walking itself. With reference to grade elevation, it is likely that it does limit performance owing to the stresses of induced mechanical inefficiency. However, there is no evidence which indicates that the same inefficiency is not encountered during running. Subjects of the AF group ran (or more precisely, jogged) to higher levels on the 4.5 mph running test VO
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388
B. A. STAMFORD
2. Maximum
TABLE
fro,
mrtx,
VO 2
maxml
Max
HR
Max
R
Max
VE
Highest
Variable
3.5 mph Walk
4.5 mph Walk
ml.
3,745
3,764 zt464 45.78 h3.83 203 zt6.03 1.03 Ito. 147.84 &23.13 13.75 h2.30 159 zt7.77
mine1
9kg-l
Values
l
zt425 45.72 zt4.53 208 xk7.09 1.05 rtO.036 145.38 k22.21 20.5 zt2.45 160 zt9.63
min-l
(BTPS)
grade,
Warm-up
performance data of average jt group (N = 12)
y0
HR are means
rt SD.
3. Maximum
TABLE
2 max,
VO
2 max, ml-kg-’
Max
HR
Max
R
Max
VE
Highest
ml*min.l
Warm-up Values
min-1
(BTPS)
grade,
y0
HR are means
& SD.
4. Maximum
TABLE
2 max, ml. min-l
VO
2 max, ml
Max
HR
Max
R
Max
VE
Highest Warm-up Values
l
kg+
l rein-l
(BTPS)
grade,
y0
HR are means
of2.36
significant
5.5 mph Run
3,973 &459 48.37 zt3.68 203 h6.45 1.03 ho.023 140.22 h23.04 15.75 zt2.96 159 rt9.64
(Jog)
3,962 A386 48.37 h4.23 203 zt9.76 1.03 zto.040 145.03 &23.48 12.5 h2.23 159 All .42
7.0 mph Run
8.5 mph Run
F Ratio
3,998 rf473 48.96 rt3.98 203 zt7.28 1.03 zlzO.036 l39.02 ~20.76 8.0 zt2.18 160 zt12.33
3,908 rt484 47.61 h4.31 207 k7.06 1.03 zto .053 139.49 A16.61 4.25 rfil.95 159 zt9.64
3.457’ 3.816” 1.208 0.593 0.414
0.164
at P < 0.05, 3.31 at
Vol.
APPLIED
PHYSIOLOGY 1975.
39, No. 3, September
Maximal
Printed
in U.S.A.
oxygen
and running
uptake
during
at various
BRYANT A. STAMFORD Exercise Physiology Laboratory,
state
RESEARCH
for
the
of training;
LITERATURE
assessment
of
locomotor
speed
is replete maximum
with oxygen
University of Louisville,
measures uptake
three males,
2 max
(8)
Kentucky 40208
participating 2) highly
trained walkers.
(running
experimental trained (running)
and
race
groups: males,
walking)
I)
average
fit
and 3) highly competitive race
METHODS
A total of 19 male undergraduate and graduate students and faculty members at the University of Louisville volunteered follows:
as
subjects
(Table
1).
Subjects
were
grouped
as
group I (N = 12) was composed of individuals who were not currently involved in a cardiovascular endurance training program nor had they been trained previously. Group I members were considered of average fitness (AF). Group II (N = 7) was composed of individuals currently involved in cardiovascular endurance training for the purpose of maintaining previously induced fitness levels. Five of the subjects comprising Group II were former track (middle distance) and/or cross country runners. Group II members were considered of high fitness (HF). An additional group, group III, composed of highly fit competitive race walkers (CRW, N = 3) were selected from the greater Louisville area. Subjects assigned to group I each performed a total of six maximal performance tests. All subjects were familiarized with treadmill walking and running prior to performance of their first test. Tests were randomly assigned thus avoiding an ordered pattern in the testing schedule. With the exception of a modified Balke walking test, all tests were discontinuous in nature. Preceding the Balke test (and all other maximal performance tests) was a lo-min warm-up consisting of walking at 3.5 mph on a 10 % grade. The warm-up was followed by a 5-min rest period. The Balke test was performed at a constant walking speed of 3.5 mph. Subjects began walking at a 10 % grade which was subsequently elevated 2.5 % every 2 min. Testing was terminated voluntarily by the subject. Throughout all tests subjects were verbally encouraged to perform to maximal limits. Expired air was collected for each succeeding minute following a heart rate of 180 beats/min. The remaining five Vo2 max tests were performed at speeds of 4.5, 5.5, 7.0, and 8.5 mph. Testing at 4.5 mph
proposed (002
Louisville,
The purpose of the present study was to compare 002 lnax and associated physiological responses elicited during treadmill walking and running at a variety of locomotor speeds. In addition the effects of state of training were examined as comparisons of the aforementioned tests were made within
max).
Among the most widely accepted measures are cycling on a stationary bicycle ergometer and walking and running on a motor-driven treadmill. vo2 max has been found to be consistently higher during treadmill (walking or running) performance compared with cycling (4-7). Treadmill performance is thought to elicit greater X702 max levels because of a larger working muscle mass (3). Comparisons of I702 max elicited during walking versus running are not consistent. Newton (9) reported similar 002 mav levels for the Balke walking test and a constant load running test. McArdle et al. (8) observed that the Balke walking test resulted in significantly lower i/102 max levels when compared to running tests. The same authors (8) suggest that local discomfort in the lower back and calf muscles may limit performance. It has been further suggested that a walking speed greater than that typically utilized in the Balke test (3.5 mph) may reduce muscular discomfort as grade elevations would be reduced, thus resulting in an increased VO
walking
speeds
STAMFORD, BRYANT A. Maximal oxygen uptake during treadmill walking and running at various speeds. J. Appl. Physiol. 39(3): 386389. 1975.-Three groups of male subjects, average fitness (AF, N = 1 Z), high fitness (HF, N = 7) and highly fit competitive race walkers (CRW, N = 3) performed maximal treadmill tests walking at 3.5 and 4.5 mph and running at 4.5, 5.5, 7.0, and 8.5 mph. In addition, the HF group performed a running test at 10.0 mph and the CRW group performed a walking test at 5.5 mph. All maximal oxygen uptake (vo, max> tests with the exception of the 3.5 mph walking test (modified Balke test) were discontinuous in nature. i’oz max obtained from walking tests was similar regardless of speed within each group. Walking voz max was significantly lower than running VOW max which was found to be similar over a speed range of 4.5 to 8.5 mph in the AF group. Running at 4.5 mph (HF group) and 4.5 and 5.5 mph (CRW group) resulted in lower Vo2 max levels than running at speeds 2 7.0 mph. Associated physiological variables (heart rate, ventilation, and respiratory exchange ratio) did not demonstrate a discernable pattern with reference to mode of locomotion (walking versus running) or speed. It was concluded that \ioz max elicited during walking is independent of speed and less than VOW Inax obtained during running. Running VOW max was interrelated with speed of running and state of training.
VO 2 maxi
treadmill
l
386
Downloaded from www.physiology.org/journal/jappl by ${individualUser.givenNames} ${individualUser.surname} (163.015.154.053) on October 21, 2018. Copyright © 1975 American Physiological Society. All rights reserved.
vQ2
max
9
WALKING
VS.
RUNNING,
VARIOUS
SPEEDS
387
I. Personal data of subjects in groups 1, I., and I.1
TABLE Group
I II III Values
N
12 7 3
Age, yr 25.1 23.3 20.6
are means
zt 2.7 zt 0.4 & 1.4
Height,
177.3 175.4 177.8
cm
=t 3.6 AZ 3.2 AZ 3.7
Weight,
80.7 67.1 64.9
tested. At 7.0 mph, mean 002 max (ml kg-’ min-l) for the AF group was 48.96, 65.42 for the HF group, and 68.40 for the CRW group. These findings agree with Astrand’s classification of average and highly fit individuals (1). Mean Vo 2 Max for AF subjects (Table 2) was similar for walking tests at 3.5 and 4.5 mph and significantly lower (approx 6 %) than results of running tests which were also similar over a range of 4.5-8.5 mph. Max HR, \j~, and R were highest (not significantly) during the 3.5 mph walking test. Warm-up HR levels revealed an expected consistency among all tests. If an improved fitness level was achieved, the effects were likely balanced by random test scheduling. The highest grade elevation obtained during each test was inversely related to speed with the exception that running at 4.5 mph was performed to higher levels than walking at the same speed. VOW max and associated physiological measures for HF subjects (Table 3) were qualitatively similar to those obtained for AF subjects with the exception that walking at 3.5 mph and walking and running at 4.5 mph were not significantly different. Running speeds ranging from 5.5 to 10.0 mph resulted in similar VOW max levels. VOW lnax results obtained for CRW subjects (Table 4) were similar for walking speeds of 3.5, 4.5, and 5.5 mph. An increase (not significant) in Vo 2 max was noted for running speeds of 4.5 and 5.5 mph. CRW subjects demonstrated a significant increase in V02 max during running at 7.0 and 8.5 mph compared with results obtained during walking. Maximal grade elevation attained demonstrated a similar pattern in HF and CRW subjects as was described for AF subjects. In each of the three groups tested, there was no discernible pattern in max HR, R, or VE with reference to walking versus running or speed. Warm-up HR was progressively reduced from AF to HF to CRW subjects as fitness level increased. l
kg
=t 4.9 zt 3.0 zt 2.8
A SD.
included both walking and running. The term running was utilized for all performances whereby there was no period in which both feet were in contact with the running surface at one time. It is obvious that at reduced speeds of 4.5 and 5.5 mph, individuals were jogging rather than running. However, the term running, as described, encompasses both jogging and running and therefore was preferred for consistency. It sh .ould be noted that there was absolu tely no problem encountered in having subjects maintain a running pattern at reduced speeds. Tests conducted at 4.5 and 5.5 mph were initiated at a grade of 5 % and tests at 7.0 and 8.5 mph were initiated at 0%. Work bouts of 3-min duration were alternated with lo-min rest periods. Work bouts of 3 min have been shown to be effective for the attainment of 002 max at highintensity work (2, IO). Grade elevation was increased 2.5 % for each successive bout and expired air was collected during each of the final 2 min of work. This procedure continued until subjects were unable to complete a given 3-min work bout. Group II subjects performed each of the aforementioned tests plus an additional running test at 10.0 mph. Likewise, an additional test (walking) was performed by group 111 subjects at 5.5 mph. Tests conducted at 4.5 and 5.5 mph for groups II and 11. subjects were initiated at 10 %. Tests conducted at 7.0, 8.5, and 10.0 mph were initiated at 5 %, 2.5 %, and 0 %, respectively. All tests were conducted at the same time of day for each subject and separated by a minimum of 48 h. Pretest protocol was emphasized and included reporting to the laboratory in a well rested condition a minimum of 2 h following the intake of food. During exercise, expired air was collected in meteorological balloons as subjects breathed through a Collin’s triple-J valve. Ventilatory volume (VE) was determined on a Parkinson-Cowan dry gasmeter. Air samples were drawn in Z-liter bags and immediately analyzed for 02 and CO2 concentration by means of Beckman Es and LB-Z analyzers. Gas analyzers were regularly calibrated with known concentrations of standardized gases. Heart rate (HR) was recorded electrocardiographically during the final 15 s of each gas collection minute. data included an analysis Statistical analysis of obtained of variance for repeated measures and the Scheffe post hoc tests. Statistical significance was established at the 0.05 level. RESULTS
Tables 2-4 present mean values & standard deviations max HR, maximum respiratory exchange for Vo max (STPD), ratio (R), max VE (BTPS), maximum grade elevation atHR. There were tained for a given test, and warm-up significant differences in fitness among the three groups
DISCUSSION
The modified Balke test elicited significantly lower 2 max levels than running tests performed by the AF, HF, and CRW groups. These results are in agreement with those reported by McArdle et al. (8). The same authors (8) suggest that local discomfort in the lower back and calf muscles may limit performance and that perhaps a faster walking speed may alleviate this problem. Results obtained in the present study indicate that increasing the speed of walking from 3.5 to 4.5 mph does not increase VOW nlax (nor does it appear to alleviate muscular discomfort). Subjects repeatedly expressed complaints concerning the discomfort associated with the 4.5 mph walking test. Overwhelmingly, this test was considered the least preferable of all tests performed. The lower Vo 2 max associated with walking compared to running may be attributable to either the excessive grade elevations encountered or the act of walking itself. With reference to grade elevation, it is likely that it does limit performance owing to the stresses of induced mechanical inefficiency. However, there is no evidence which indicates that the same inefficiency is not encountered during running. Subjects of the AF group ran (or more precisely, jogged) to higher levels on the 4.5 mph running test VO
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388
B. A. STAMFORD
2. Maximum
TABLE
fro,
mrtx,
VO 2
maxml
Max
HR
Max
R
Max
VE
Highest
Variable
3.5 mph Walk
4.5 mph Walk
ml.
3,745
3,764 zt464 45.78 h3.83 203 zt6.03 1.03 Ito. 147.84 &23.13 13.75 h2.30 159 zt7.77
mine1
9kg-l
Values
l
zt425 45.72 zt4.53 208 xk7.09 1.05 rtO.036 145.38 k22.21 20.5 zt2.45 160 zt9.63
min-l
(BTPS)
grade,
Warm-up
performance data of average jt group (N = 12)
y0
HR are means
rt SD.
3. Maximum
TABLE
2 max,
VO
2 max, ml-kg-’
Max
HR
Max
R
Max
VE
Highest
ml*min.l
Warm-up Values
min-1
(BTPS)
grade,
y0
HR are means
& SD.
4. Maximum
TABLE
2 max, ml. min-l
VO
2 max, ml
Max
HR
Max
R
Max
VE
Highest Warm-up Values
l
kg+
l rein-l
(BTPS)
grade,
y0
HR are means
of2.36
significant
5.5 mph Run
3,973 &459 48.37 zt3.68 203 h6.45 1.03 ho.023 140.22 h23.04 15.75 zt2.96 159 rt9.64
(Jog)
3,962 A386 48.37 h4.23 203 zt9.76 1.03 zto.040 145.03 &23.48 12.5 h2.23 159 All .42
7.0 mph Run
8.5 mph Run
F Ratio
3,998 rf473 48.96 rt3.98 203 zt7.28 1.03 zlzO.036 l39.02 ~20.76 8.0 zt2.18 160 zt12.33
3,908 rt484 47.61 h4.31 207 k7.06 1.03 zto .053 139.49 A16.61 4.25 rfil.95 159 zt9.64
3.457’ 3.816” 1.208 0.593 0.414
0.164
at P < 0.05, 3.31 at
