Background
Physical activity (PA) is associated with a favorable metabolic risk profile in adults. However, its role in adolescents remains unclear. In this study, using data (2019–2021) from the 8th Korea National Health and Nutrition Examination Survey, we investigated the optimal exercise type for preventing metabolic complications in adolescents.
Methods
A total of 1,222 eligible adolescent participants (12–18-year-old) were divided into four groups as follows: aerobic exercise (AE), resistance exercise (RE), combined aerobic and resistance exercise (CE), and no exercise (NE). Daily PA was assessed using the international PA questionnaire. Blood samples were collected to measure lipid, glucose, and insulin levels. Additionally, the homeostasis model assessment for insulin resistance (HOMA-IR) and triglyceride-glucose (TyG) indices were measured. Multivariate regression analysis was used to compare the metabolic risk factors across the PA groups before and after propensity score matching (PSM) adjustment for confounding variables.
Results
The CE group exhibited improved fasting glucose levels, lower TyG index, reduced white blood cell count, and higher high-density lipoprotein (HDL) cholesterol levels than the NE group. The RE group exhibited lower mean blood pressure, triglyceride, fasting insulin, HOMA-IR, TyG index and a reduced risk of metabolic syndrome than the NE group. The AE group had higher total and HDL cholesterol levels. In detailed comparison of the AE and RE groups, the RE group consistently exhibited favorable metabolic parameters, including lower blood pressure and total and low-density cholesterol levels, which persisted after PSM.
Conclusion
These findings highlight the positive effects of PA on cardiovascular risk factors in adolescents. Thus, RE may have a more favorable metabolic effect than AE. Further studies are needed to validate the benefits of exercise according to the exercise type.

Citations

• Triglyceride-glucose index and the progression of chronic obstructive pulmonary disease, panvascular disease, and multimorbidity: a prospective cohort study
  Shuo Zhang, Xiaotian Li, Jiajing Li, Siwei Xie, Zongbin Wang, Zhijie Zheng, Jie Huang, Shuduo Zhou
  Frontiers in Cardiovascular Medicine.2026;[Epub]     CrossRef
• Reflecting on progress and challenges: the Korean Journal of Family Medicine in 2024
  Seung-Won Oh
  Korean Journal of Family Medicine.2025; 46(2): 55.     CrossRef
• Lifestyle interventions for hypertension management in primary care: a narrative review
  Byoungduck Han, Gyu Bae Lee, Jihyun Yoon, Yang-Hyun Kim
  Ewha Medical Journal.2025; 48(4): e56.     CrossRef

Background
: This study was conducted to find out the difference of heart rate variability between practicing Tai Chi and walking at 6 km/hr.

Methods : Twelve healthy volunteers aged 25 to 35 were recruited through advertisement. All the subjects gave their informed consent, and the study was approved by the Institutional Review Board of the Catholic Medical Center Research Foundation. The subjects either practised Tai Chi or walked at 6 km/ hr on a treadmill machine, maintaining 5-minute rest, 20-minute exercise, and 30-minute rest. After 1 week, they switched and performed the other form of exercise. During the exercise, beat-to-beat HRV data was recorded by Polar S-810. We calculated HRV indices using Matlab software program and analyzed the mean value of HRV indices.

Results : The differences of the mean value of HRV indices of pre-exercise resting period were not significant. However, repeated ANOVA revealed that there were significant differences of change in the mean of SDNN (-14.27±13.03 ms, -33.67±20.23 ms; P=0.023), RMSSD (-10.17±9.59 ms, -21.90±12.60 ms; P=0.087), and STIDX (171.60±196.84, 1003.49±812.56; P=0.003) between practising Tai Chi and walking. The differences of change in mean heat rate, LF/HF ratio, LF, HF and TP were not significant. The differences of the mean value of HRV indices of the post-exercise resting period were not significant compared to the pre-exercise period.

Conclusion : The result of this study suggest that exertional intensity of practising Tai Chi is similar to that of walking. Moreover, practising Tai Chi may be more profitable than walking in the aspect of HRV.