. 2019 Mar 15;10:265. doi: 10.3389/fphys.2019.00265

Table 3.

Metabolic and physiological responses at the studied submaximal intensity levels (50%HRmax, 75%HRmax) of the incremental cycle exercise test to exhaustion for the three groups: normal weight (NW), overweight (OW), and obese (OB) adolescents.

	NW (N = 15)	OW (N = 15)	OB (N = 15)	Group effect (df = 2)

				F	p
At 50%HRmax
$\dot{V}$ O_2net (L⋅min^-1)	1.32 (0.02)	1.68 (0.02)^a	1.81 (0.02)^a,b	42.1	<0.0001
PO (W)	80 (5)	80 (10)	80 (10)	1.3	0.31
Lactate (mmol⋅L^-1)	3.9 (1.9)	3.8 (1.7)	4.1 (1.1)	2.6	0.36
HR (beats⋅min^-1)	104.7 (2.1)	106.2 (3.1)	102.9 (6.1)	0.6	0.54
RER	0.78 (0.05)	0.82 (0.04)^a	0.89 (0.07)^a,b	11.2	<0.01
%LO	48 (2)	39 (1)^a	22 (3)^a,b	20.2	<0.0001
%CHO	52 (2)	61 (1)^a	78 (3)^a,b	20.1	<0.0001
E(W)	458 (11)	562 (32)^a	615 (14)^a,b	30.1	<0.0001
Epinephrines (nmol⋅L^-1)	1.61 (0.1)	0.98 (0.2)^a	0.82 (0.1)^a,b	8.6	<0.01
Norepinephrines (nmol⋅L^-)	5.4 (0.3)	4.2 (0.3)^a	3.9 (0.4)^a,b	19.4	<0.001
At 75%HRmax
$\dot{V}$ O_2net (L⋅min^-1)	2.01 (0.04)	2.02 (0.02)	2.01 (0.03)	2.1	0.22
PO (W)	140 (5)	120 (10)^a	120 (10)^a	11.8	<0.001
Lactate (mmol⋅L^-1)	6.9 (1.9)	6.8 (1.7)	6.1 (1.1)	2.6	0.36
HR (beats⋅min^-1)	144.2 (2.2)	152.2 (2.1)	148.9 (2.1)	0.9	0.56
RER	0.89 (0.05)	0.87 (0.04)	0.87 (0.07)	1.6	0.64
%LO	8 (2)	9 (1)	8 (3)	11.2	0.46
%CHO	92 (2)	91 (1)	92 (3)	3.1	1.1
E (W)	685 (12)	684 (12)	681 (19)	2.1	2.2
Epinephrines (nmol⋅L^-1)	2.01 (0.1)	1.81 (0.2)	1.51 (0.4)^a,b	6.6	<0.01
Norepinephrines (nmol⋅L^-1)	7.4 (0.2)	5.9 (0.3)^a	5.3 (0.1)^a,b	11.1	<0.001

Values are presented as mean (standard deviation). $\dot{V}$ O_2net: oxygen consumption above the resting level, PO: power output, HR: heart rate, RER: respiratory exchange ratio, %LO: percent contribution of lipid oxidation to energy, %CHO: percent contribution of carbohydrate oxidation to energy, E: energy consumption. ^aSignificant difference with NW (p < 0.01). ^bSignificant difference with OW (p < 0.01).