PMID 31620178

Research
All papers

Benefits of 10 weeks of high-intensity interval training and green tea supplementation on cardiovascular risk factors and VO(2max) in overweight women

Ghasemi E, Nayebifar S

Question

Do green tea supplementation and field-style HIIT, separately or together, improve cardiovascular risk factors, body composition, and VO2max in overweight women?

Summary

In 30 overweight young women, 10 weeks of shuttle-run HIIT with green tea tablets improved lipids, fibrinogen, body composition, and VO2max more than green tea alone or HIIT with placebo for several outcomes. The paper did not describe adverse events, and the intervention mixed exercise with supplementation, so it is not clean HIIT-only evidence.

Methodology

  • Overweight women aged 20-30 years
  • 30 participants.
  • 40-m shuttle running.
  • Intensity: 85-95% HRmax.
  • 3 days/week.
  • 10 weeks.
  • Randomized placebo-controlled clinical trial with three parallel groups
  • Lipid panel, Fibrinogen, VO2max, and Body composition were tracked.

Outcomes

lipids

TG and LDL decreased in all groups; HDL increased significantly only in the two HIIT groups.

Within-group TG, LDL p<=0.05; HDL p=0.012 in both HIIT groups

Improved

VO2max

VO2max increased significantly in HIIT plus green tea and HIIT plus placebo, not green tea alone.

HIIT groups p=0.007; green tea p=0.06

Improved

body composition

Weight and body fat percentage decreased in all groups, with larger changes generally favoring HIIT plus green tea.

Between-group ANCOVA p<=0.05; pairwise results favor HIIT plus green tea for body fat and weight

Improved

safety

The article did not provide clear adverse-event reporting.

Unclear

Insights

  • For overweight young women, 3 weekly high-intensity shuttle sessions can improve VO2max over 10 weeks.
  • Supplement co-interventions should be separated from workout claims in frontend copy.
  • Lack of safety reporting means this is not strong evidence for unsupervised beginner safety.

Limitations

  • Small groups of 10
  • Women aged 20-30 only
  • Green tea supplementation and diet controls confound exercise-only effects
  • Adherence and adverse events not reported in useful detail
  • Exact interval timing not clearly available in text outside table

Safety

  • The article did not report adverse events, injuries, or symptoms during the 10-week intervention.
  • Eligibility and exclusions screened out disease history, medication or antioxidant supplement use, hormonal tablets or supplements, pregnancy, travel, and irregular exercise attendance.
  • The article states none of the 30 participants were excluded from the statistical population; HIIT intensity was monitored with a Polar heart-rate watch.