AbstrakLatar Belakang: Diabetes Melitus merupakan penyakit kronis yang berdampak luas dan dikenal sebagai silent killer karena sering tanpa gejala awal namun dapat menimbulkan komplikasi serius jika tidak ditangani dengan baik. Salah satu faktor risiko utama terjadinya diabetes yaitu gaya hidup sedentari atau kurangnya aktivitas fisik. Kegiatan Car Free Day (CFD) berpeluang besar untuk mendeteksi kebiasaan aktifitas fisik terhadap kadar gula darah dalam deteksi kesehatan. Tujuan: mengetahui korelasi aktifitas fisik terhadap kadar gula darah pada peserta CFD di Rindam IV/Diponegoro Kota Magelang tahun 2025. Metode: menggunakan desain kuantitatif korelatif dengan pendekatan cross-sectional. Pengambilan data dilakukan pada 97 peserta CFD yang mengikuti skrining kesehatan pada 1 dan 8 Juni 2025 spesifik pada pemeriksaan gula darah. Analisis hubungan menggunakan uji Mann Whitney Test. Hasil: Menunjukkan karakteristik responden pada jenis kelamin hampir seluruhnya perempuan (66,0%), kategori usia didominasi pada kategori pra lansia (46,4%), pendidikan didominasi oleh tingkat pendidikan SMA (51,5%). Gambaran kadar gula darah pada kategori normal (84,5%), sedangkan pada kebiasaan aktivitas fisik sebagian besar pada kategori ya (52,6%). Uji statistik Mann–Whitney Test diketahui perbedaan yang signifikan kadar gula darah antara yang memiliki kebiasaan aktifitas fisik dan yang tidak (p-value = 0,000 < 0,05), dengan nilai Mean Rank kadar gula darah pada peserta yang tidak melakukan aktifitas fisik 59,97 dengan rata-rata kadar gula darah 174,56 mg/dL, sedangkan pada kelompok yang melakukan aktifitas fisik adalah 39,10 dengan rata-rata kadar gula darah 130,02 mg/dL. Simpulan: kebiasaan aktifitas fisik berhubungan dengan lebih rendahnya kadar gula darah peserta pada populasi CFD. Kata Kunci: aktifitas fisik; Car Free Day; kadar gula darah; skrining kesehatan. AbstractBackground: Diabetes Mellitus is a chronic disease that has a wide impact and is known as a silent killer because it often has no initial symptoms but can cause serious complications if not treated properly. One of the main risk factors for diabetes is a sedentary lifestyle or lack of physical activity. Car Free Day (CFD) activities have a great opportunity to detect physical activity habits on blood sugar levels in health detection. Objective: to determine the correlation of physical activity on blood sugar levels in CFD participants at Rindam IV / Diponegoro, Magelang City in 2025. Method: using a correlative quantitative design with a cross-sectional approach. Data collection was carried out on 97 CFD participants who participated in health screening on June 1 and 8, 2025 specifically on blood sugar examinations. Relationship analysis used the Mann Whitney Test. Results: Showing the characteristics of respondents in terms of gender, almost all of them were female (66.0%), the age category was dominated by the pre-elderly category (46.4%), and education was dominated by high school education (51.5%). The picture of blood sugar levels was in the normal category (84.5%), while in terms of exercise habits, most were in the yes category (52.6%). The Mann–Whitney statistical test revealed a significant difference in blood sugar levels between those who engaged in physical activity and those who did not (p-value = 0.000 < 0.05). The mean rank of blood sugar levels in participants who did not engage in physical activity was 59.97 with an average blood sugar level of 174.56 mg/dL, while in the group who engaged in physical activity, the mean rank was 39.10 with an average blood sugar level of 130.02 mg/dL. Conclusion: Physical activity habits are associated with lower blood sugar levels in participants in the CFD population. Keywords: physical activity; Car Free Day; blood sugar levels; health screening