The increasing prevalence of sedentary behavior among young adults is a growing public health concern, particularly due to its association with metabolic disorders such as type 2 diabetes mellitus (T2DM) and cardiovascular diseases (1). Sedentary lifestyles, characterized by prolonged periods of physical inactivity, can lead to insulin resistance and impaired glucose metabolism even in apparently healthy individuals (2). Conversely, regular physical activity has been shown to improve insulin sensitivity and promote effective glucose utilization by skeletal muscles, thereby reducing the risk of developing hyperglycemia and its long-term complications (3,4).

Fasting blood glucose (FBG) and glycated hemoglobin (HbA1c) are key indicators of glycemic control. While FBG provides an immediate measure of blood sugar levels,  over the preceding two to three months (5). These parameters are widely used for the diagnosis and monitoring of diabetes and prediabetes, and they serve as valuable tools in preventive screening for young individuals at risk (6).

Previous studies have indicated that physically active individuals tend to have better glycemic profiles compared to their sedentary counterparts (7,8).

However, the relationship between physical activity levels and glycemic indices in non-diabetic young adults remains underexplored, particularly in developing countries where lifestyle transitions are rapidly occurring (9). Understanding these associations in young populations is crucial, as early identification of impaired glucose regulation may help prevent the progression to chronic metabolic conditions.

The present study aims to compare the fasting blood glucose and HbA1c levels in sedentary versus physically active young adults, to evaluate the potential protective role of regular physical activity on glycemic health.

Study Design and Population

This cross-sectional, comparative study was conducted among healthy young adults aged 18 to 25 years. Participants were recruited from university campuses and community settings through purposive sampling. Individuals with a known history of diabetes, cardiovascular disease, or chronic illness, and those on medications affecting glucose metabolism were excluded. A total of 100 participants were enrolled and equally divided into two groups based on their physical activity status: sedentary (n=50) and physically active (n=50).

Assessment of Physical Activity

Physical activity levels were assessed using the International Physical Activity Questionnaire–Short Form (IPAQ-SF). Participants who reported less than 600 MET-minutes/week of physical activity were categorized as sedentary, while those with ≥600 MET-minutes/week were considered physically active, as per WHO guidelines.

Anthropometric Measurements

Height and weight were measured using standard procedures, and body mass index (BMI) was calculated as weight in kilograms divided by height in meters squared (kg/m²). These parameters were recorded to assess potential confounding variables.

Blood Sample Collection and Analysis

Participants were instructed to fast overnight for a minimum of 8–10 hours before sample collection. Venous blood samples (5 mL) were collected under aseptic conditions from the antecubital vein. Fasting blood glucose was measured using the glucose oxidase-peroxidase method on an automated chemistry analyzer. HbA1c was estimated using high-performance liquid chromatography (HPLC), which provides accurate long-term glycemic control data.

Statistical Analysis

Data were entered into Microsoft Excel and analyzed using SPSS version 25.0. Results were expressed as mean ± standard deviation (SD). An independent samples t-test was used to compare mean FBG and HbA1c levels between the two groups. A p-value of less than 0.05 was considered statistically significant.

A total of 100 participants were enrolled in the study, with 50 individuals in the sedentary group and 50 in the physically active group. The mean age of participants was 22.3 ± 1.8 years in the sedentary group and 21.9 ± 1.6 years in the active group (p = 0.342). The two groups were comparable in terms of gender distribution and BMI (Table 1).

Fasting Blood Glucose and HbA1c Levels

The mean fasting blood glucose level among sedentary individuals was found to be significantly higher (96.4 ± 8.2 mg/dL) compared to the physically active group (88.1 ± 7.6 mg/dL), with a p-value < 0.001. Similarly, the mean HbA1c level was also elevated in the sedentary group (5.7 ± 0.3%) versus the active group (5.3 ± 0.2%), and this difference was statistically significant (p < 0.001) (Table 2).

These findings indicate that physical activity has a favorable impact on glycemic control, even among non-diabetic young adults.

Table 1: Demographic Characteristics of Study Participants

Table 2: Comparison of Glycemic Parameters Between Groups

As shown in Table 2, statistically significant differences in both FBG and HbA1c levels were observed between the two groups,

suggesting a strong inverse relationship between physical activity and glycemic indicators.

The present study evaluated and compared fasting blood glucose (FBG) and glycated hemoglobin (HbA1c) levels between sedentary and physically active young adults. The findings revealed significantly higher FBG and HbA1c levels in the sedentary group, indicating poorer glycemic control relative to their physically active counterparts. These results align with several previous investigations that have reported the beneficial role of physical activity in modulating glucose homeostasis (1–3).

Physical activity improves insulin sensitivity through multiple mechanisms, including enhanced glucose uptake by skeletal muscles, increased GLUT-4 translocation, and improved mitochondrial function (4,5). Even moderate levels of physical exertion have been shown to reduce insulin resistance, which is a precursor to type 2 diabetes (6). Our findings support this physiological rationale, highlighting that even in apparently healthy young adults, physical inactivity may predispose individuals to early metabolic disturbances.

The significant difference in HbA1c levels between groups further emphasizes the long-term impact of physical activity on glycemic regulation. As HbA1c reflects average glucose levels over the past 2–3 months, it serves as a robust indicator of chronic glycemic exposure (7). Studies have shown that regular exercise can reduce HbA1c levels by approximately 0.5–0.7% in both diabetic and prediabetic populations (8,9), and similar trends have been reported in non-diabetic individuals with sedentary lifestyles (10).

Additionally, increased sedentary behavior has been associated with chronic low-grade inflammation, endothelial dysfunction, and adipose tissue dysregulation—all of which contribute to impaired glucose tolerance and increased HbA1c levels (11,12). A meta-analysis by Wilmot et al. reported that sedentary individuals have a significantly higher risk of metabolic syndrome and diabetes, independent of BMI or caloric intake (13).

Our results corroborate findings from an Indian study by Tripathy et al., which demonstrated a higher prevalence of prediabetes among college students with low physical activity scores (14). Similarly, a cross-sectional survey conducted in Malaysia observed elevated HbA1c levels in inactive young adults compared to those meeting physical activity guidelines (15).

Although the study sample was limited to a single geographic region and relatively small in size, the statistically significant differences observed suggest a potentially larger trend that warrants further investigation. Future longitudinal studies with larger sample sizes and objective physical activity monitoring (e.g., accelerometry) would help strengthen the evidence.

This study demonstrates that physically active young adults exhibit significantly lower fasting blood glucose and HbA1c levels compared to their sedentary counterparts. These findings highlight the importance of regular physical activity in maintaining optimal glycemic control and reducing the early risk of metabolic disorders, even among healthy individuals. Promoting active lifestyles in youth may serve as a preventive strategy against future development of type 2 diabetes.

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