Background: Hemoglobin (Hb) plays a critical role in oxygen transport and is essential for maintaining normal physiological functions and physical performance. Physical activity is known to induce hematological adaptations that may improve hemoglobin levels and overall health status.

Aim: To evaluate the effect of a structured physical activity intervention on hemoglobin levels among young adults.

Materials and Methods: This prospective interventional study was conducted among 60 healthy participants aged 18–25 years. Participants were divided into two groups: Group 1 (control, n=30) and Group 2 (physical activity intervention, n=30). The intervention group participated in supervised moderate-intensity aerobic exercises, including jumping, skipping, and squatting, for 30 minutes per day, five days per week for 12 weeks, while the control group maintained their usual lifestyle. Venous blood samples were collected before and after the intervention period, and hemoglobin concentration was measured using an automated hematology analyzer. Data were analyzed using SPSS version 26.0. Paired t-test and independent sample t-test were applied, with p<0.05 considered statistically significant.

Result: The mean Hb level in the control group remained unchanged from baseline (13.94 ± 1.36 g/d) to post-intervention (13.94 ± 1.30 g/dL) (p=0.914). In contrast, the intervention group demonstrated a significant increase in mean Hb level from 13.16 ± 1.42 g/dL to 14.52 ± 1.36 g/dL following the intervention (p<0.001). The findings indicate that regular physical activity significantly improved hemoglobin concentration.

Conclusion: Structured moderate-intensity physical activity significantly enhances hemoglobin levels in young adults and may serve as an effective non-pharmacological strategy for improving hematological health and oxygen-carrying capacity.