Author(s): ZHU, Y., CAO, M., SHAO, S., Institution: BEIJING SPORT UNIVERCITY, Country: CHINA, Abstract-ID: 820

INTRODUCTION:
The World Health Organization has observed a rising trend in obesity rates across Europe, raising significant concerns[1]. High-Intensity Interval Training (HIIT) has effectively improved body composition and metabolic health in adults[2]. This study aims to observe the effects of different HIIT training protocols over a 12-week period on body composition, cardiorespiratory fitness, muscle strength, and blood parameters in obese college students.
METHODS:
A total of 63 obese college students with a BMI of 25.6 ± 1.7 were recruited. They were randomly assigned to three groups using SPSS: Treadmill HIIT group (HIIT-T n=21): Each interval consisted of 30 seconds of fast running (10-13 km/h) followed by 30 seconds of recovery walking (4 km/h),total 8 times. The wholebody HIIT group (HIIT-W n=21) performed bodyweight resistance training:8 exercises to boost cardio and strength, rest 30 seconds between exercises. Both groups will play 3 sets, with a 3 minute break between sets. All training was monitored via heart rate monitors (Polar Team Pro, Finland), maintaining intensity within 75–80% HRmax (220 minus age). Due to physiological adaptation to prolonged training, both HIIT groups increased intensity (>80% HRmax) starting in week 6. The control group (CG, n=21) maintained their original study and living habits during the experiment but did not engage in any additional exercise training. Intervention effectiveness analysis employed paired t-tests for comparisons, while intergroup differences in each indicator were assessed using one-way analysis of variance.
RESULTS:
Both exercise regimens significantly improved body composition (weight, BMI, body fat percentage, and body fat mass, P<0.05). Only the treadmill group showed a significant reduction in visceral fat area by 7.32 cm² (P<0.01). After 12 weeks, the HIIT-T and HIIT-W programs improved subjects' 20-meter repeated sprint test performance by 5.82 laps and 4.67 laps, respectively.Maximal oxygen uptake (VO₂max) increased by 1.91 mL·kg⁻¹·min⁻¹ and 1.74 mL·kg⁻¹·min⁻¹ (P<0.01) . Grip strength increased by 1.53 kg and 2.98 kg, respectively (P<0.01). Intergroup comparisons revealed that HIIT-T produced superior improvements in cardiorespiratory fitness, while the HIIT-W demonstrated greater grip strength gains than the HIIT-T (P<0.05). Furthermore, analysis of five blood markers (TG; TC; HDL-C; LDL-C; GLU) revealed that only GLU showed a highly significant improvement in the HIIT-T (p<0.01). The HIIT-W exhibited a substantial reduction in TG by approximately 27.6% (P<0.05) and a decrease in LDL by 0.3 mmol/L. In comparison, the HIIT-W demonstrated superior improvement in lipid metabolism.
CONCLUSION:
HIIT boosts fitness in obese young adults. HIIT-T cuts visceral fat, but HIIT-W excels by enhancing muscle strength, cardiorespiratory fitness, adaptability to diverse settings, and lower barriers. Thus, HIIT-W is a more efficient, sustainable regimen ideal for youth lifestyles.
1.Elisabeth M,(2022) 2.Newsome et al. (2024)