Comparative Effects of High-Intensity Interval Training and Low-Intensity Steady-State Exercise on Anthropometric...

Area of Science:

• Exercise Physiology
• Sports Science
• Human Kinetics

Background:

• Limited real-world comparative data exists for High-Intensity Interval Training (HIIT) vs. Low-Intensity Steady-State (LISS) exercise.
• Standardized anthropometric assessments and subjective measures are crucial for evaluating exercise effectiveness.
• This pilot study addresses the gap by comparing HIIT and LISS in a practical setting.

Purpose of the Study:

• To compare the 12-week effects of HIIT and LISS on anthropometric outcomes using ISAK measurements.
• To evaluate post-intervention subjective perceptions of exercise effectiveness.
• To provide evidence for individualized exercise prescription in personal training.

Main Methods:

• Twenty-four physically active adults were randomized into HIIT (n=12) or LISS (n=12) groups.
• Supervised training involved three sessions/week for 12 weeks, with intensity monitored by heart rate (HIIT: 80-95% HRmax; LISS: 60-70% HRmax).
• ISAK-standardized anthropometric measurements were taken at baseline and weeks 4, 8, and 12; subjective perceptions were assessed post-intervention.

Main Results:

• Both HIIT and LISS significantly reduced body mass, BMI, fat mass, and circumferences (p < 0.001) without between-group differences.
• Somatotype changes included decreased endomorphy and increased ectomorphy in both groups.
• HIIT preserved/increased muscle mass (group × time interaction, p < 0.001), while LISS improved psychological well-being (p = 0.002) and HIIT enhanced perceived performance (p = 0.002-<0.001).

Conclusions:

• HIIT and LISS yield comparable body composition improvements in real-world settings.
• Exercise type influences subjective outcomes: LISS benefits psychological well-being, HIIT enhances perceived performance.
• Findings support tailoring exercise interventions (HIIT vs. LISS) to individual goals and preferences.