PMID 41286960

Research
All papers

Comparison of the acute effects of traditional and reaction-based HIIT on brain connectivity and cognitive responses

Çağın M, Cicioğlu Hİ, Ertan H

Question

How do acute traditional and reaction-based HIIT sessions affect EEG brain connectivity, Stroop responses, perceived exertion, and heart rate in elite athletes?

Summary

In 33 elite young athletes, one acute 10-minute bodyweight HIIT session was compared with a reaction-cued version using colored light signals and a seated control condition. Both HIIT formats targeted 85% maximum heart rate; reaction-based HIIT produced higher perceived exertion despite similar heart rates and showed EEG connectivity changes interpreted as more cognitively demanding.

Methodology

  • Elite athletes from 11 sport branches
  • 33 participants.
  • Bodyweight intervals with color reaction cues.
  • Work intervals: 20 seconds.
  • Recovery: 10 seconds, plus 1 minute between two rounds.
  • Intensity: 85% maximum heart rate.
  • 10 minutes HIIT after 5-minute warm-up.
  • Single acute session.
  • Single session.
  • Randomized acute controlled experimental study
  • EEG connectivity, Perceived exertion, and Heart rate were tracked.

Outcomes

Connectivity

Reaction-based HIIT increased fronto-temporal synchronization; traditional HIIT showed changes in fronto-occipital and occipito-temporal regions.

Multiple significant group/time interactions were reported across frequency bands and electrode pairs.

Mixed

RPE

Reaction-based HIIT produced higher perceived exertion than traditional HIIT.

Traditional 7.27 +/- 1.34 versus reaction-based 8.73 +/- 0.78; p=.003.

Safety concern

Heart rate

Mean heart rate was similar between traditional and reaction-based HIIT.

Traditional 171.9 +/- 3.01 bpm; reaction-based 170.82 +/- 1.94 bpm; p=.162.

No clear change

Insights

  • Reaction cues can add cognitive load to familiar 20:10 bodyweight HIIT.
  • Perceived difficulty may rise even when heart rate is similar.
  • Use reaction-based HIIT cautiously for users who already tolerate the underlying movements.

Limitations

  • Acute-only design
  • Small athlete groups
  • No long-term adherence or performance outcomes
  • EEG connectivity outcomes are not directly translatable to general fitness claims

Safety

  • No adverse events were reported in the the paper.
  • Dizziness, blurred vision, or failure to complete HIIT were exclusion criteria.