Acute effects of high-intensity interval training and moderate-intensity continuous training on ectopic lipid in overweight and obese youth
10.3969/j.issn.1000-6710.2024.08.005
- VernacularTitle:急性高强度间歇运动和中等强度持续运动对超重和肥胖青年异位脂肪的影响
- Author:
Zepeng LU
1
;
Jiao LI
;
Jiahengnuer JIALIN
;
Huadan XUE
;
Dapeng BAO
Author Information
1. 北京体育大学竞技体育学院(北京 100084)
- Keywords:
high-intensity interval training;
moderate-intensity continuous training;
ectopic lipid;
magnetic resonance imaging
- From:
Chinese Journal of Sports Medicine
2024;43(8):619-627
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the acute effect of high-intensity interval training(HIIT)and moder-ate-intensity continuous training(MICT)on ectopic lipid levels in overweight and obese youth.Methods Twenty obese or overweight subjects,aged 24.15±1.98 years,participated in two crossover random-ized own-control trials of HIIT and MICT.In HIIT,participants performed high-intensity cycling at 85%VO2max for 9 sets of 2 minutes,interspersed with low-intensity cycling at 25%VO2max for 10 sets of 2 minutes each and the session started and ended with low-intensity cycling at 25%VO2max.Howev-er,in MICT,all participants cycled continuously at 50%VO2max for 60 minutes,maintaining a pedal-ing speed of 50-55 rpm,with a 7-day interval between the two interventions.Before,as well as im-mediately,60 and 120 minutes after exercise intervention,all subjects underwent magnetic resonance imaging(MRI)scans to observe the fat fraction(FF)and spin relaxation rate R2* of the rectus femo-ris,biceps femoris and liver.Results Rectus femoris FF decreased significantly immediately after HIIT and MICT(P<0.05),without significant differences.Moreover,sixty minutes after MICT,rectus femoris FF returned to pre-exercise levels,while 120 minutes after HIIT,the values restored to the pre-exer-cise levels.However,no significant changes were found in the biceps femoris and liver FF before and after the two exercise interventions(P>0.05).Meanwhile,the rectus femoris R2* was significantly lower in both the HIIT and MICT groups immediately after exercise(P<0.05)and remained significantly low-er in both groups 120 minutes after the exercise(P<0.05),with no significant differences between the two groups.Biceps femoris and liver R2* were significantly higher in both groups immediately after the exercise intervention(P<0.05).Liver R2* returned to pre-exercise levels 120 minutes after HIIT group,but remained significantly lower than pre-intervention levels after MICT(P<0.05).Conclusion Both acute HIIT and MICT are effective in reducing intramuscular fat in the working muscles of over-weight and obese adults but have no significant effect on liver fat.Acute HIIT and MICT show similar fat-burning effects,but a single bout of exercise proves more effective for fat loss in the active mus-cles compared to the antagonist muscles.
