Dose-response relationship between combined aerobic-resistance training, health-related quality of life, and GDF-15 and MDA levels in adults aged 65 to 85 years

Abstract

Objective: The aging process is associated with a decline in health-related quality of life (HRQoL), which is often exacerbated by increases in biological markers such as growth differentiation factor-15 (GDF-15) as a marker of cellular vulnerability and stress, and malondialdehyde (MDA) as a marker of lipid oxidative damage. These markers play a key role in predicting physiological decline and age-related diseases. This cross-sectional observational study aimed to investigate the dose-response relationship between combined aerobic-resistance training volume, HRQoL, and serum levels of GDF-15 and MDA in adults aged 65 to 85 years.

Method: 200 participants (105 women, 95 men; mean age 74 ± 2.5 years) were selected from the active elderly community in Tehran. Weekly exercise volume was measured using the International Physical Activity Questionnaire (IPAQ-SF) and divided into three levels (low <150 min/week), moderate (150-300 min), and high (>300 min). HRQoL was assessed with the SF-36 questionnaire, and GDF-15 and MDA levels were determined by fasting blood test. Statistical analysis included multivariate linear regression, ANOVA.

Results: Increasing the training volume was associated with a significant improvement in HRQoL score (β = 0.47, p = 0.001), a decrease in GDF-15 levels (β = 0.35, p = 0.001), and MDA levels (β = 0.30, p = 0.001). The dose-response relationship was nonlinear, and the greatest improvement was observed at moderate to high levels. Gender differences also showed that women showed a better response to moderate training.

Conclusion: Combined aerobic-resistance training can reduce oxidative damage and cellular vulnerability and improve HRQoL. These findings emphasize the need to plan personalized exercise interventions for the elderly.