Table 3.
Measurements during maximal exercise (VO
2max
) testing (n = 7). Values are Mean ± SD.
Variables
LCHF
HCLF
P Value
Pre
Day 1
Post
Day 39
Pre
Day 1
Post
Day 39
Condition
Time
Interaction
Maximal Data
Time to Exhaustion (sec)
844.3 ± 87.3
818.6 ± 114.5
775.7 ± 107.4
801.4 ± 74.9
0.251
1.000
0.206
VO
2max
(ml/kg/min)
61.6 ± 3.1
62.9 ± 6.9
60.6 ± 8.4
62.5 ± 6.0
0.435
0.027
0.854
VO
2max
(L/min)
4.2 ± 0.2
4.3 ± 0.6
4.2 ± 0.6
4.3 ± 0.4
0.476
0.088
0.773
VCO
2max
(L/min)
4.6 ± 0.3
4.4 ± 0.7
4.7 ± 0.7
4.9 ± 0.5
0.022
0.812
0.316
HR
max
(b/min)
180.9 ± 11.4
181.1 ± 10.0
178.6 ± 15.0
179.2 ± 10.5
0.195
0.757
0.881
V
Emax
(L/min)
115.3 ± 26.1
121.3 ± 23.5
119.0 ± 17.1
125.2 ± 20.9
0.514
0.086
0.987
RR
max
(bpm)
47 ± 10
47 ± 8
48 ± 8
47 ± 9
0.774
0.920
0.613
Peak RER
1.09 ± 0.09
1.03 ± 0.08
1.13 ± 0.07
1.14 ± 0.05
0.004
0.176
0.072
Peak Carbohydrate Oxidation (g/min)
7.2 ± 1.5
6.2 ± 1.6
8.0 ± 1.5
8.5 ± 1.2
0.009
0.522
0.148
Peak Fat Oxidation (g/min)
1.01 ± 0.21
1.26 ± 0.20
0.67 ± 0.14
0.66 ± 0.23
0.001
0.093
0.072
Average Data
Mean VO
2
(ml/kg/min)
44.8 ± 2.5
45.2 ± 4.0
43.7 ± 4.4
44.3 ± 3.1
0.134
0.588
0.906
Mean VO
2
(L/min)
3.1 ± 0.2
3.1 ± 0.3
3.0 ± 0.3
3.0 ± 0.2
0.283
0.738
0.523
Mean VCO
2
(L/min)
2.8 ± 0.3
2.6 ± 0.3
2.9 ± 0.4
3.0 ± 0.2
0.015
0.465
0.149
Mean V
E
(L/min)
70.7 ± 19.0
71.9 ± 15.9
72.9 ± 13.0
77.4 ± 14.5
0.216
0.053
0.588
Mean RR (bpm)
34 ± 7
34 ± 6
36 ± 8
36 ± 8
0.064
0.850
0.845
Mean RER
0.9 ± 0.06
0.83 ± 0.05
0.95 ± 0.04
0.96 ± 0.03
0.001
0.042
0.050
Mean Carbohydrate Oxidation (g/min)
3.0 ± 0.9
2.1 ± 0.8
3.6 ± 0.8
3.7 ± 0.4
0.001
0.106
0.075
Mean Fat Oxidation (g/min)
0.43 ± 0.34
0.74 ± 0.25
0.16 ± 0.22
0.13 ± 0.18
0.001
0.032
0.047
LCHF, low carbohydrate high fat; HCLF, high carbohydrate low fat; VO
2
= oxygen consumption; VCO
2
= carbon dioxide production; HR = heart rate; RER = Respiratory exchange ratio; V
E
= ventilation; RR = Respiratory Rate