Acute effects of resistance-type and cycling-type high-intensity interval training on arterial stiffness, cardiac autonomic modulation and cardiac biomarkers

Wang T, Mao J, Bo S, Zhang L, Li Q

Question

Do cycling-type and resistance-type HIIT sessions with similar duration and intensity produce different acute effects on arterial stiffness, cardiac autonomic modulation, systolic blood pressure, and cardiac biomarkers in healthy young men?

Summary

In a randomized crossover study, 11 healthy active young men performed both cycling-type HIIT and resistance-type HIIT. Both protocols used 10 one-minute work intervals with one-minute recoveries after a 10-minute warmup. Resistance-type HIIT used loaded back squats and cycling-type HIIT used a cycle ergometer. The squat-based protocol reduced cardio-ankle vascular index more immediately after exercise, while both protocols produced similar temporary changes in heart-rate variability and cardiac biomarkers that returned or moved toward baseline by 30-35 minutes.

Methodology

Eleven healthy active young male undergraduate physical education students from Beijing, China.
11 participants.
Behind-the-neck barbell back squats.
Work intervals: 60 seconds.
Recovery: 60 seconds.
Intensity: 20% bodyweight barbell load; metronome 60 beats/min; eccentric phase 1 second and concentric phase as fast as possible; RPE-matched to C-HIIT.
10-minute warmup plus 19-minute exercise intervention.
Single acute session.
Single acute bout.
Randomized crossover acute exercise trial
Average cardio-ankle vascular index, Systolic blood pressure, Heart-rate variability, and Cardiac troponin-T were tracked.

Outcomes

Average CAVI

Both protocols reduced CAVI immediately and 30 minutes after exercise; R-HIIT produced a larger immediate reduction than C-HIIT.

Time x group interaction P = 0.019, partial eta squared 0.182; time main effect P < 0.001, partial eta squared 0.729; immediate R-HIIT versus C-HIIT difference -0.60 +/- 0.30, P = 0.043, d = 0.924

Improved

Systolic blood pressure

SBP changed acutely over time after both HIIT modes and returned near baseline by 30 minutes, with no significant mode difference.

Interaction P = 0.179; group P = 0.580; time P = 0.001, partial eta squared 0.304

Mixed

Heart-rate variability

lnHF and lnRMSSD decreased and LF/HF increased immediately after both protocols; parasympathetic markers remained below baseline at 30 minutes, with no significant mode differences.

lnHF time P < 0.001, partial eta squared 0.782; lnRMSSD time P < 0.001, partial eta squared 0.693; LF/HF time P = 0.001, partial eta squared 0.302; no significant interactions or group effects

Mixed

Cardiac troponin-T

cTnT increased 5 minutes after both protocols and was not different from resting value by 35 minutes; no mode difference was observed.

Interaction P = 0.293; group P = 0.804; time P = 0.023, partial eta squared 0.193

Mixed

NT-proBNP

NT-proBNP increased 5 minutes after both protocols and was not different from resting value by 35 minutes; no mode difference was observed.

Interaction P = 0.208; group P = 0.789; time P = 0.001, partial eta squared 0.334

Mixed

Insights

A 10 x 60-second, 1:1 work-rest HIIT structure can be delivered through both cycling and resistance exercise, but acute vascular responses may differ by mode.
Squat-based loaded R-HIIT may not be a broadly safe default despite favorable acute CAVI response in healthy young men.
Brief HIIT can temporarily suppress HRV recovery markers; programming should allow recovery after intense sessions.
Acute biomarker findings in healthy active men should not be used as clinical safety claims for higher-risk users.

Limitations

Acute-only intervention
Very small sample
All participants were healthy active young men
No long-term training outcomes
Only one R-HIIT exercise mode was tested
No longer cTnT follow-up beyond 35 minutes
No explicit adverse-event reporting found

Safety

No explicit adverse-event results were found in the paper.
Cardiac biomarkers increased transiently after both HIIT modes and returned to non-different-from-baseline values by 35 minutes.
HRV parasympathetic markers were still below baseline at 30 minutes after exercise.
The authors cautioned that the behind-the-neck squat R-HIIT protocol may cause lower-body overexertion.