Participants
Twenty two participants took part in the study, and they have ages mean 29.27 standard deviation (S.D.) 6.97 ranged 21-49 years old, heights mean 168.45 SD 10.14 ranged 155-191 cm, weights mean 71.69 SD 10.12 ranged 51-120 kg, body mass index (BMI) mean 25.01 SD 4.92 ranged 20.4-40.7, and 10 male and 12 female.
Variables given by Oxycon Mobile ® system
VO2 mean ml/min
The level of oxygen consumption (VO2 mean, ml/min) in the S1, S2, S3 showed strong correlation with T1, T2, T3, where S1 and T1 are baseline cadence in stepper and treadmill movements, S2 and T2 represents 20% higher cadence than the baseline one, and S3 and T3 20% lower cadence than the baseline one. Mean values showed that S3 consumed more energy than T3 by approximately 14% (Table 1). The correlation coefficient between stepper and treadmill movements in VO2 is very strong (0.789, p< 0.001) and a linear regression was constructed as seen in Figure 4.
EqO2 mean in S1 (28.992) was very close to T1 mean value (28.33). It was found that the difference between S3 and T3 was significant, and T3 was higher than S3 by approximately 6% (Table 2). The correlation coefficient was also strong (0.489, p <0.001) and linear regression as seen in Figure 5. The mean at Rest was observed at 33.560, which was significantly higher than the other situations, because EqO2 is reversely proportional to VO2.
Table 2 EqO2 when using stepper and treadmill
Measure
|
Mean
|
Std. Error
|
95% Confidence Interval
|
p
|
Note
|
Lower Bound
|
Upper Bound
|
EqO2Mean
|
R
|
33.6
|
1.1
|
31.2
|
35.9
|
<0.001
|
vs all
|
S1
|
29.0
|
0.7
|
27.6
|
30.4
|
0.455
|
vs T1
|
S2
|
29.0
|
0.7
|
27.5
|
30.5
|
0.560
|
vs T2
|
S3
|
28.2
|
0.6
|
26.9
|
29.4
|
<0.001
|
vs T3
|
T1
|
28.3
|
0.8
|
26.6
|
30.1
|
|
|
T2
|
28.6
|
0.7
|
27.1
|
30.1
|
|
|
T3
|
29.9
|
0.5
|
28.8
|
31.0
|
|
|
Volume of CO2 expired
VCO2, which is the production of carbon dioxide per minute, was recorded. It is found that S1 and S3 were higher than T1 and T3 by approximately 16% and 11% respectively (Table 3). The correlation coefficient between two types of movements is 0.778 (p<0.001) as seen in Figure 6.
Table 3 VCO2 Volume of CO2 expired while using stepper and treadmill.
Dependent Variable
|
Mean
|
Std. Error
|
95% Confidence Interval
|
p
|
note
|
Lower Bound
|
Upper Bound
|
VCO2mean
ml/min
|
R
|
234.0
|
16.9
|
198.5
|
269.4
|
<0.001
|
vs all
|
S1
|
799.9
|
69.8
|
653.8
|
945.9
|
<0.008
|
vs T1
|
S2
|
859.8
|
71.8
|
709.6
|
1010.1
|
0.905
|
vs T2
|
S3
|
670.8
|
54.1
|
557.6
|
784.0
|
<0.031
|
vs T3
|
T1
|
690.8
|
52.6
|
580.7
|
800.9
|
|
|
T2
|
853.0
|
63.7
|
719.8
|
986.2
|
|
|
T3
|
598.8
|
55.3
|
483.0
|
714.7
|
|
|
Breathing equivalent for carbon dioxide
The mean for EqCO2, the minute volume and carbon dioxide output, was recorded in Table 4. It was found that S1 and S3 were lower than T1 and T3 by approximately 6% and 10%, respectively (Table 4). The correlation coefficient is 0.652 with p<0.001 as in Figure 7, showing a strong correlation.
Table 4 Breathing equivalent for carbon dioxide
Measure
|
Mean
|
Std. Error
|
95% Confidence Interval
|
p
|
note
|
Lower Bound
|
Upper Bound
|
EqCO2Mean
|
R
|
36.5
|
1.1
|
34.2
|
38.8
|
<0.001
|
vs all
|
S1
|
30.6
|
0.6
|
29.3
|
31.8
|
<0.022
|
vs T1
|
S2
|
31.3
|
0.7
|
29.7
|
32.8
|
0.300
|
vs T2
|
S3
|
32.5
|
0.7
|
30.9
|
34.0
|
<0.001
|
vs T3
|
T1
|
32.5
|
0.8
|
30.8
|
34.2
|
|
|
T2
|
32.1
|
0.8
|
30.3
|
33.9
|
|
|
T3
|
34.1
|
0.8
|
32.4
|
35.7
|
|
|
Respiratory exchange ratio (RER)
RER mean values showed a correlation between stepper and treadmill as in Figure 8, and S1 and S2 higher than T1 and T2 by approximately 8% and 6% respectively (Table 5). The correlation coefficient is 0.507 with p< 0.001, again confirming the correlation between the stepper and treadmill movements.
Table 5 Respiratory exchange ratio in stepper and treadmill measurements
Measure
|
Mean
|
Std. Error
|
95% Confidence Interval
|
p
|
note
|
Lower Bound
|
Upper Bound
|
RER Mean
|
R
|
.920
|
.018
|
.882
|
.959
|
<0.05
|
vs S3,T1
|
S1
|
.950
|
.017
|
.915
|
.985
|
<0.001
|
vs T1
|
S2
|
.929
|
.014
|
.900
|
.958
|
<0.009
|
vs T2
|
S3
|
.871
|
.011
|
.848
|
.893
|
0.332
|
vs T3
|
T1
|
.873
|
.015
|
.840
|
.905
|
|
|
T2
|
.893
|
.012
|
.867
|
.919
|
|
|
T3
|
.881
|
.013
|
.854
|
.908
|
|
|
Energy consumption using stepper and treadmill (EE)
At Rest, the lowest mean of energy consumption (EE) was recorded as 1791.723. It was found that S3 was significantly higher than T3 by approximately 14% as shown in Table 6. The correlation coefficient was 0.790 with p<0.001 as in Figure 9, showing strong correlation between two types of movements.
Table 6 Energy expenditure
Measure
|
Mean
|
Std. Error
|
95% Confidence Interval
|
p
|
note
|
Lower Bound
|
Upper Bound
|
EE mean Kcal/min
|
R
|
1791.7
|
130.1
|
1519.4
|
2064.1
|
<0.001
|
vs all
|
S1
|
5979.2
|
472.1
|
4991.1
|
6967.3
|
0.129
|
vs T1
|
S2
|
6557.5
|
518.3
|
5472.7
|
7642.3
|
0.597
|
vs T2
|
S3
|
5420.0
|
447.0
|
4484.4
|
6355.7
|
<0.018
|
vs T3
|
T1
|
5592.0
|
437.4
|
4676.5
|
6507.5
|
|
|
T2
|
6774.3
|
519.1
|
5687.9
|
7860.7
|
|
|
T3
|
4769.2
|
418.6
|
3893.1
|
5645.3
|
|
|
Ventilation (VE)
VE mean value showed that S1 was higher than T1 by approximately 9% in Table 7. The correlation coefficient between stepper and treadmill is 0.826 with p<0.001 as Figure 10.
Table 7 Ventilation (VE) while using stepper and treadmill
Measure
|
Mean
|
Std. Error
|
95% Confidence Interval
|
p
|
note
|
Lower Bound
|
Upper Bound
|
VE Mean
L/min
|
R
|
9.6
|
0.7
|
8.2
|
11.1
|
<0.001
|
vs all
|
S1
|
26.2
|
2.2
|
21.5
|
30.8
|
<0.042
|
vs T1
|
S2
|
28.9
|
2.7
|
23.3
|
34.6
|
0.916
|
vs T2
|
S3
|
23.5
|
1.8
|
19.8
|
27.1
|
0.115
|
vs T3
|
T1
|
24.0
|
1.7
|
20.4
|
27.6
|
|
|
T2
|
29.1
|
2.2
|
24.5
|
33.7
|
|
|
T3
|
21.8
|
1.7
|
18.2
|
25.5
|
|
|
MET using stepper and treadmill
Mean value for MET showed that S3 is higher than T3 by approximately 15% in Table 8. The correlation coefficient for MET was 0.598 with p<0.001 as Figure 11, so two type of movements were correlated.
Table 8 MET while using stepper and treadmill
Measure
|
Mean
|
Std. Error
|
95% Confidence Interval
|
p
|
note
|
Lower Bound
|
Upper Bound
|
MET Mean
|
R
|
1.0
|
0.1
|
0.9
|
1.1
|
<0.001
|
vs all
|
S1
|
3.2
|
0.2
|
2.8
|
3.6
|
0.221
|
vs T1
|
S2
|
3.5
|
0.2
|
3.2
|
3.9
|
0.513
|
vs T2
|
S3
|
3.0
|
0.2
|
2.7
|
3.3
|
<0.002
|
vs T3
|
T1
|
3.0
|
0.1
|
2.7
|
3.3
|
|
|
T2
|
3.7
|
0.2
|
3.2
|
4.2
|
|
|
T3
|
2.6
|
0.1
|
2.3
|
2.8
|
|
|
Qtc
Qtc results showed correlation between stepper and treadmill as well, with the coefficient as 0.806 with p<0.001 as in Figure 12. It is also found that S3 is higher than T3 by approximately 11% as in Table 9.
Table 9 Qtc comparison between stepper and treadmill
Measure
|
Mean
|
Std. Error
|
95% Confidence Interval
|
p
|
note
|
Lower Bound
|
Upper Bound
|
Qtc Mean
L/min
|
R
|
1.9
|
0.1
|
1.6
|
2.1
|
<0.001
|
vs all
|
S1
|
5.5
|
0.4
|
4.6
|
6.4
|
0.323
|
vs T1
|
S2
|
6.1
|
0.5
|
5.1
|
7.1
|
0.682
|
vs T2
|
S3
|
5.0
|
0.4
|
4.2
|
5.9
|
<0.033
|
vs T3
|
T1
|
5.3
|
0.4
|
4.4
|
6.1
|
|
|
T2
|
6.3
|
0.5
|
5.3
|
7.2
|
|
|
T3
|
4.5
|
0.4
|
3.8
|
5.3
|
|
|