Effect of Different Volumes of Interval Training and Continuous Exercise on Interleukin-22 in Adults with Metabolic Syndrome: A Randomized Trial

Figures & data

Figure 1 Flowchart for IL-22 sub-study. MICT, moderate-intensity continuous training; 4HIIT, 4 X 4 min high-intensity interval training; 1 x 4 min high-intensity interval training.

Figure 2 Schematic representation of MICT (A), 4HIIT (B) and 1HIIT (C).

Table 1 Participants’ Characteristics

Variables	MICT (n=10)	4HIIT (n=13)	1HIIT (n=16)	P-value
Demographics
Age, years, mean ± SD	54 ± 9	54 ± 10	57 ± 8	0.47
Male sex, %	50	69	69	0.56
Type 2 diabetes, %	20	62	56	0.10
Hypertension, %	60	85	75	0.41
Medications
ACEIs, %	30	46	56	0.43
Calcium Antagonist, %	0	23	13	0.26
Beta-blocker, %	20	0	19	0.24
Statin, %	20	46	63	0.11
Aspirin, %	20	23	19	0.96
Metformin,%	10	38	38	0.26

Abbreviations: MICT, moderate-intensity continuous training; 4HIIT, 4xX4min high-intensity interval training; 1HIIT, 1X4min high-intensity interval training; ACEIs, angiotensin-converting enzyme inhibitors.

Table 2 Changes in Metabolic Syndrome Severity, Fitness, Fatness, and Other Cardiometabolic Parameters Following Different Types of Training in All Participants

	MICT (n=10)		Effect Size Within Group	4HIIT (n=13)		Effect Size Within Group	1HIIT (n=16)			Effect Size Within Group	Group Difference
	Baseline	Change	Cohen’s d or r (95% CI)	Baseline	Change	Cohen’s d or r (95% CI)	Baseline		Change	Cohen’s d or r (95% CI)	p value Adjusted for Baseline Value	η^2 Adjusted for Baseline Value
Inflammatory markers
IL-22, pg/mL	28.9 (10.4 to 44.4)	−17% (−43 to 31.3)	0.15	23.1 (8.8 to 45.2)	16.5% (−18.9 to 154.9)	0.30	29.8 (13.9 to 152.9)		15.9% (−28.7 to 46.1)	0.02	0.14	0.14
HsCRP, mg/l	1.8 (0.8 to 3.1)	−33% (−43 to −4.7)	0.38	1.4 (0.9 to 2.8)	24% (−12 to 124)	0.28	1.8 (0.6 to 1.9)		3% (−94 to 5)	0.07	0.24	0.07
Metabolic syndrome severity
Metabolic syndrome z-score	1.8	−0.5±1.8	0.22	2.7	−0.5±0.9	0.22	2.4		−1.3±1.8	0.40	0.31	0.06
Metabolic syndrome risk factors
Triglycerides, mmol.l^−1	1.5 (1.3 to 1.8)	0.03 (−0.4 to 0.4)	0.03	2.2±0.8	0.03±0.7	0.03	1.8±0.8		−0.2±0.6	0.23	0.82	0.01
HDL-C, mmol.l^−1	1.3±0.3	0.03±0.3	0.09	1.00 (0.9 to 1.1)	−0.01 (−0.2 to 0.03)	0.17	1.1±0.4		0.2±0.2	0.44	0.03	0.17
Fasting glucose, mmol.l^−1	5.7 (5.3 to 6.5)	−0.2 (−0.8 to 0.4)	0.10	6.3 (5.2 to 8.0)	−0.05 (−0.6 to 0.4)	0.06	6.5 (5.3 to 7.9)		−0.46 (−0.62 to 0.71)	0.16	0.82	0.01
Waist circumference, cm	108±15	−1±5	0.06	106±12	−2±5	0.17	102±13		−2±4	0.15	0.73	0.02
Systolic blood pressure, mmHg	130±13	−5±9	0.32	126±10	1±10	0.20	137±13		−9±9	0.62	0.21	0.06
Diastolic blood pressure, mmHg	86±10	−4±6	0.40	83±8	−5±7	0.67	84±9		−5 (−9 to 1)	0.44	0.74	0.01
HOMA-IR	6.9±4.9	−2.1±2.7	0.51	5.9±1.9	−0.8±1.4	0.51	5.2 (3.7 to 6.8)		−1.2 (−1.6 to 0.7)	0.32	0.41	0.05
Cardiorespiratory fitness
Absolute V̇O2peak, l.min^−1	2.3	0.3±0.2	0.40	2.4	0.5±0.4	0.46	2.3		0.2±0.2	0.43	0.16	0.10
Relative V̇O2peak, mL.kg^−1.min^−1	23.2	2.7±1.9	0.42	23.2	5.7±4.7	0.82	26.2		2.9±2.2	0.38	0.03	0.18
Body Composition
Visceral adipose tissue, g	1159.2±316.8	−47.2±152.6	0.15	1154.5±404.2	−68.2±106.0	0.39	1037.9±338.7		−44.9±102.7	0.13	0.84	0.01
Total body fat, %	43.4±8.4	−0.3±1.9	0.02	40.5±6.7	−1.2±1.8	0.18	38.1±7.5		−0.8±1.5	0.11	0.36	0.06
Android fat, %	48.7±7.3	−0.2±2.3	0.03	46.7±5.3	−1.4±2.3	0.26	44.1±5.3		−1.4±2.7	0.28	0.23	0.08
Gynoid fat, %	42.2±9.8	−0.3±1.6	0.03	39.2±7.0	−0.8±2.0	0.11	36.1±8.5		−0.4±1.5	0.05	0.72	0.02
Lean Mass, kg	54.2±13.3	−0.2±2.2	0.02	56.3±10.6	0.04±1.8	<0.01	53.3±11.9		−0.1±1.2	<0.01	0.93	<0.001
Weight, kg	100.7±21.9	−0.4±4.5	0.01	100.6±19	−2.7±5.9	0.16	92.1±21.7		−2.3±3.9	0.11	0.37	0.05
Body mass index, kg.m^2 −1	34±6.5	−0.2±1.5	0.03	30.6 (29.7 to 35.6)	−0.6 (−1.3 to 0.3)	0.28	30.8±6.1		−0.1±2.9	0.03	0.80	0.01

Abbreviations: ANCOVA, analysis of covariance; MICT, moderate-intensity continuous training; 4HIIT, 4X4min high-intensity interval training; 1HIIT, 1X4min high-intensity interval training. Variables are reported as mean change ± SD or percent/absolute median change (IQR).