PMID 39639405

Research
All papers

Gut microbiota and metabolic responses to a 12-week caloric restriction combined with strength and HIIT training in patients with obesity: a randomized trial

Nechalová L, Bielik V, Hric I, Babicová M, Baranovičová E, Grendár M, Koška J, Penesová A

Question

How does a 12-week calorie-restriction program combined with strength and HIIT training affect gut microbiota and metabolic health in adults with obesity?

Summary

In adults with obesity, a 12-week program combining calorie restriction, supervised strength training, and HIIT improved body composition and liver enzymes and changed gut-microbiota measures compared with baseline and non-intervention controls. Because diet, strength training, and HIIT were bundled together, the study cannot show what HIIT alone caused.

Methodology

  • Adults with obesity
  • 23 participants.
  • Strength training and HIIT circuits.
  • Work intervals: 30-45 seconds during HIIT exercises.
  • Recovery: 15-30 seconds during HIIT circuits.
  • 60 minutes.
  • 2 guided sessions/week.
  • 12 weeks.
  • Randomized controlled trial with bundled diet and exercise intervention
  • Body composition, Liver enzymes, Gut microbiota, and Metabolites were tracked.

Outcomes

Body composition

Intervention participants reduced BMI, body weight, body-fat percentage, waist, hip, and visceral fat.

The paper reported significant within-intervention changes; waist circumference had a significant group interaction (p=0.018).

Improved

Liver enzymes

AST, ALT, and GMT decreased in the intervention group.

Reported as significant in the full text.

Improved

Microbiota

Some taxa associated with obesity-related research increased, while several SCFA-producing bacteria decreased.

Specific taxa reported as significantly changed; alpha diversity did not significantly differ.

Mixed

Lipids

Lipid-profile group interaction was not significant in the the paper, with baseline values described as near optimal.

No clear change

Insights

  • Do not attribute this study's benefits to HIIT alone because calorie restriction and strength training were co-delivered.
  • Circuit-style 30-45 second intervals are translatable as a format, but the missing intensity target limits workout-generation precision.
  • Retention and medical exclusions matter for obesity-focused programs.

Limitations

  • Small sample
  • High dropout
  • Bundled diet, strength, and HIIT intervention
  • No detailed control diet/activity data
  • No stool consistency data
  • No direct adverse-event reporting

Safety

  • No adverse events were directly reported in the the paper.
  • Dropouts were mainly due to antibiotic treatment for common infections or non-compliance.