Comparative Effects of High-Intensity Interval Training and Low-Intensity Steady-State Exercise on Anthropometric Outcomes and Psychophysical Well-Being: A Pilot Study

Di Domenico F, Esposito G, Aliberti S, Ceruso R, Raiola G

Question

How do supervised HIIT and LISS compare over 12 weeks for anthropometry and post-intervention psychophysical perceptions in active adults?

Summary

In a 12-week supervised real-world pilot, physically active adults doing HIIT and those doing low-intensity steady-state exercise both improved body mass, BMI, fat mass, and waist/hip measures. HIIT appeared better for preserving or slightly increasing muscle mass and perceived performance, while LISS participants reported higher psychological well-being.

Methodology

Twenty-four physically active adults in supervised personal training.
24 participants.
Multi-joint circuit.
Work intervals: 30 seconds.
Recovery: 30 seconds active recovery; 2 minutes passive recovery between rounds.
Intensity: 85-95% HRmax during work intervals; 80-95% HRmax overall.
50-60 minutes.
3 sessions/week.
12 weeks.
Pilot quasi-experimental parallel-group study
Body composition, Well-being, and Perceived performance were tracked.

Outcomes

Fat mass

Both HIIT and LISS improved body mass, BMI, fat mass, and waist/hip measures with no primary endpoint between-group difference.

Time effects p<0.001; no between-group difference for primary endpoint.

Improved

Muscle mass

Muscle mass preservation or slight gain favored HIIT.

Group x time p<0.001; HIIT trend +0.63 kg p=0.06, d=0.81.

Improved

Perceptions

LISS had higher psychological well-being, while HIIT had greater perceived performance improvement.

Psychological well-being p=0.002; performance p=0.002 to <0.001.

Mixed

Insights

HIIT and LISS can both be presented as viable supervised body-composition options for active adults.
HIIT programming may emphasize performance and muscle-preservation goals; LISS may fit users prioritizing psychological well-being.

Limitations

Small pilot sample.
Non-random allocation.
Not energy-expenditure matched.
Nonvalidated post-only subjective questionnaire.
Physically active young adults only.

Safety

No adverse events were reported in the reviewed article text.
Participants with recent musculoskeletal injury or cardiovascular/metabolic contraindications were excluded; all sessions were supervised and heart-rate monitored.