Abstract
erobic endurance is crucial for sports students who rely on optimal respiratory health for sustained activity. This study investigates the impact of smoking, Body Mass Index (BMI), and lung function, specifically Forced Vital Capacity (FVC), on aerobic endurance. Conducted with a cross-sectional design, the study involved 35 sports students aged 19.23±0.92 years who met specific inclusion criteria. Data were collected through smoking behavior questionnaires, BMI measurements, spirometry for FVC, and beep tests for endurance. Results showed smoking did not significantly affect FVC (sig 0.460 > α = 0.05) or endurance (sig 0.089 > α = 0.05). BMI had a significant effect on FVC (sig 0.037 < α = 0.05), but not on endurance (sig 0.917 > α = 0.05). FVC itself did not significantly influence endurance (sig 0.684 > α = 0.05). Smoking and BMI accounted for 14.5% of the variance in FVC, while smoking, BMI, and FVC together explained
(sig 0.089 > α = 0.05). BMI had a significant effect on FVC (sig 0.037 < α = 0.05), but not on endurance (sig 0.917 > α = 0.05). FVC itself did not significantly influence endurance (sig 0.684 > α = 0.05). Smoking and BMI accounted for 14.5% of the variance in FVC, while smoking, BMI, and FVC together explained only 9.51% of the variation in aerobic endurance. The study concludes that BMI significantly affects FVC, but neither smoking nor BMI directly impacts aerobic endurance. These findings highlight that endurance is influenced by more than lung capacity alone. Despite no immediate effects of smoking on endurance, its long-term risks remain concerning. Emphasis should be placed on cardiovascular and high-intensity training, along with weight management. Future research should explore factors like oxygen uptake, training intensity, and genetic predispositions to understand endurance performance better. Keywords Aerobic Endurance, Respiratory Health, FVC, BMI, Smoking 1. Introduction Aerobic endurance is a fundamental component of sports performance, particularly for college students who engage in high-intensity physical activities that require sustained oxygen consumption [1], [2]. Various physiological and behavioral lifestyle elements, such as tobacco use and Body Mass Index (BMI) and Forced Vital Capacity FVC, significantly influence endurance levels and overall respiratory health [3]. Smoking has long been recognized as a major risk factor for respiratory dysfunction, as the inhalation of harmful chemicals from tobacco smoke damages lung tissues, reduces oxygen uptake, and impairs cardiovascular efficiency [4]. These effects can be detrimental to the sports college students, leading to decreased endurance, increased fatigue, and a higher susceptibility to respiratory illnesses. Despite widespread awareness of the harmful effects of smoking, it remains a prevalent habit among young adults, including students in
Universal Journal of Public Health 13(4): 870-876, 2025 871 college sports, often due to social influences, stress, and a lack of awareness regarding its long-term consequences [5], [6]. Similarly, BMI plays a crucial role in determining sports performance, as excessive body weight can impose additional strain on the cardiovascular and respiratory systems, leading to reduced endurance [7]. On the other hand, being underweight may result in insufficient muscle mass and energy reserves necessary for sustaining prolonged physical activity [8]. Achieving and maintaining an optimal BMI is essential for peak sports performance; however, many sports students in college struggle with weight management due to poor dietary habits, inconsistent training routines, or genetic predispositions [9]. Another critical factor influencing aerobic endurance is FVC, which refers to the total volume of air a person is capable of forcefully exhaling following a full inhalation [10], [11]. Athletes with higher lung capacity can take in more oxygen, allowing their muscles to perform efficiently during prolonged exertion, while those with reduced lung capacity may experience impaired endurance and suboptimal sports performance [12]–[14]. Although lung capacity plays a crucial role in determining aerobic fitness, limited research has examined its direct relationship with endurance in sports students. Numerous studies have explored the individual effects of smoking, BMI, and lung capacity on aerobic endurance, but research that integrates these three factors within the context of college sports students remains limited. Studies on smoking and sports performance consistently show negative correlations. Jeon, et al. [15] found that smoking leads to reduced oxygen transport, increased airway resistance, and decreased lung elasticity, all of which contribute to impaired aerobic endurance. Similarly, Elsaidy, et al. [16] demonstrated that student-athletes who smoked exhibited significantly lower VO₂ max levels compared to their non-smoking peers. VO₂ max, or maximal oxygen uptake, is a key indicator of aerobic fitness, and any decline in this measure can hinder sports performance [17], [18]. Research on BMI and endurance presents mixed findings, as while obesity is generally associated with reduced aerobic capacity due to increased metabolic demands and respiratory inefficiencies, some studies suggest that a slightly higher BMI may be
max, or maximal oxygen uptake, is a key indicator of aerobic fitness, and any decline in this measure can hinder sports performance [17], [18]. Research on BMI and endurance presents mixed findings, as while obesity is generally associated with reduced aerobic capacity due to increased metabolic demands and respiratory inefficiencies, some studies suggest that a slightly higher BMI may be beneficial for certain sports. Zapadka, et al. [19] found that endurance athletes with moderate BMI values performed better than those at extreme ends of the spectrum. However, excessive weight—whether from fat or muscle—can negatively affect endurance, particularly in sports requiring prolonged exertion. FVC has also been widely studied in terms of respiratory health, but its direct impact on sports performance remains underexplored [20]. Szafraniec, et al. [21] found that lung capacity is a strong predictor of endurance among long-distance runners, as higher lung volumes facilitate better oxygen exchange and muscle efficiency. Likewise, Hackett [22] highlighted that lung function training can significantly enhance endurance in athletes, particularly those engaged in endurance sports. Despite these valuable insights, most existing studies examine these factors in isolation rather than as interrelated components affecting sports college students' respiratory health. A critical gap in the literature exists due to the lack of integrated analysis on the combined effects of smoking, BMI, and lung capacity on aerobic endurance. Most studies focus on one or two variables at a time, failing to consider the complex interactions between these factors. This research seeks to address this limitation by assessing these variables simultaneously to provide a more comprehensive understanding of their impact on sports college students. Another gap pertains to the limited research specifically targeting sports students in college. While some studies suggest that moderate BMI values enhance performance, others argue that maintaining a lower BMI is crucial for aerobic endurance. This study aims to clarify these inconsistencies by analyzing BMI trends among sports students in college and their endurance performance. Furthermore, while lung capacity is widely acknowledged as an important determinant of respiratory health, its interaction with smoking and BMI in the context of sports performance remains largely unexplored.
argue that maintaining a lower BMI is crucial for aerobic endurance. This study aims to clarify these inconsistencies by analyzing BMI trends among sports students in college and their endurance performance. Furthermore, while lung capacity is widely acknowledged as an important determinant of respiratory health, its interaction with smoking and BMI in the context of sports performance remains largely unexplored. By addressing these gaps, this research will contribute to a deeper understanding of the respiratory health of sports students in college and provide evidence-based insights to optimize their training and performance. The urgency of this research is underscored by several factors that impact the health and performance of sports college students. One pressing concern is the rising smoking rates among young adults. Despite anti-smoking campaigns, tobacco use remains prevalent among university students, including those involved in sports. Smoking at an early age can lead to chronic respiratory conditions, negatively affecting both sports performance and long-term health [23], [24]. Another critical issue is the increasing prevalence of obesity and sedentary lifestyles. With modern lifestyles characterized by high-calorie diets and reduced physical activity, many students struggle with maintaining an optimal BMI, which directly impacts their endurance and overall fitness. Additionally, the findings of this study have significant implications for sports college students aspiring to pursue professional or semi- professional athletic careers. Understanding how smoking, BMI, and lung capacity influence endurance can help them make informed lifestyle choices that enhance their long- term performance and prevent potential health risks. This study contributes to long-term public health by promoting awareness of the importance of respiratory health in athletic success. Poor respiratory function can lead to chronic conditions such as asthma and cardiovascular diseases, which may hinder not only athletic performance but also overall well-being. By addressing these concerns, this study aims to support sports students in optimizing their athletic performance while maintaining long-term
872 The Impact of Smoking, Body Mass Index, and Pulmonary Function on Aerobic Endurance: A Case Study of College Sports Students respiratory health. 2. Materials and Methods 2.1. Design & Participants This descriptive quantitative study has a cross-sectional research design. It was conducted to examine the influence of smoking, BMI, and lung vital capacity on aerobic endurance in sports students. For more details related to the research design, see Figure 1 below. Figure 1. Research Design The population in this study was sports students at the University. The sample was obtained by a purposive sampling technique, which was selected based on the inclusion criteria, namely: actively registered as a sports student at the university, aged 17-19 years, male, able- bodied, and willing to be a research sample, so that the sample in this study was 35 people. 2.2. Procedure The approach utilized in this research can be detailed as follows: 1. The researcher clarified the procedures involved in the study to the respondent. 2. Samples were completed, and the study's informed consent was signed. 3. Researchers took several measurements, namely: a) Body Mass Index (BMI) b) Anthropometric assessments were conducted to determine Body Mass Index (BMI) by measuring both height and weight. Height and weight were recorded, and BMI was calculated using the formula [BMI = weight (kg)/height (m)²]. The BMI values were then classified into normal weight, overweight, and obese categories, based on the definitions established by the International Obesity Task Force [25]. c) Pulmonary Function (Forced Vital Capacity “FVC”) Researchers measured FVC using a spirometer. In summary, each participant stood with their feet flat on the ground, took a deep breath, and exhaled steadily into the mouthpiece for as long as possible until no air remained. The highest value was recorded after three attempts. d) Aerobic Endurance Aerobic endurance in the participants was assessed through the beep test, which involved continuous 20- meter shuttle runs starting at a speed of 8.5 km/h, with the pace progressively increasing by 0.5 km/h at each subsequent level [26]. At the conclusion of each stage and after completing every 20-meter segment, a
value was recorded after three attempts. d) Aerobic Endurance Aerobic endurance in the participants was assessed through the beep test, which involved continuous 20- meter shuttle runs starting at a speed of 8.5 km/h, with the pace progressively increasing by 0.5 km/h at each subsequent level [26]. At the conclusion of each stage and after completing every 20-meter segment, a beep sound is emitted once. If a participant reaches the designated line before the beep is heard, they are required to pause and wait for the signal before proceeding in the opposite direction. Conversely, if the beep occurs before the participant reaches the line, they must increase their speed to cross the boundary and immediately turn back. Failure to maintain the timing of the beeps on two consecutive occasions indicates that the individual has reached their peak performance for that stage, which corresponds to one complete shuttle. The predicted VO2 max value is then estimated by correlating the final level achieved during the test with standardized beep test norms and performance feedback [7], [27]. e) Smoking The researcher explained to the sample how to fill out the smoking behavior questionnaire. The research sample was asked to fill in the questionnaire according to the actual situation. After the questionnaire was filled in, the researcher collected it. The data obtained were analysed using path analysis with SPSS. 2.3. Instruments The variables in this study consisted of 2 independent variables, namely Smoking (X1) and Body Mass Index (BMI) (X2), one intervening variable, namely Pulmonary Vital Capacity (Y), and one dependent variable, namely Aerobic Endurance (Z). The instrument used for smoking is a smoking behaviour questionnaire with validity r hit > 0.316 (item validity) and Cronbach's Alpha reliability = 0.962. Body Mass Index is measured by taking anthropometric measurements of height and weight. BMI was determined by calculating weight (kg) divided by height (m)². Height was recorded to the nearest 0.1 cm using a wall-mounted tape measure, while weight was measured to the nearest 0.1 kg with an electronic scale. Pulmonary vital capacity was assessed using a spirometer, following the guidelines of the National
measured by taking anthropometric measurements of height and weight. BMI was determined by calculating weight (kg) divided by height (m)². Height was recorded to the nearest 0.1 cm using a wall-mounted tape measure, while weight was measured to the nearest 0.1 kg with an electronic scale. Pulmonary vital capacity was assessed using a spirometer, following the guidelines of the National Physical Health Test Standard [28]. To evaluate aerobic endurance, the Beep Test was employed, providing an estimate of VO2 max, which acts as a crucial indicator of an individual's endurance capacity during prolonged aerobic activity [29]. This research utilized the beep test as a tool for assessment, which showed a face validity of 0.77 and a high reliability rating of 0.98 [30].
Universal Journal of Public Health 13(4): 870-876, 2025 873 2.4. Statistical Analysis Data were analysed using path analysis with SPSS-25. Biased and incomplete data were excluded from the data. 3. Results 3.1. Data Description This study was conducted on sports students aged 19,23±0,92 years, male. The research data consisted of an assessment of smoking behaviour, BMI, FVC, and aerobic endurance. The following is a description of the research data presented in Table 1. Table 1. Data Description Variable N Mean Median SD Smoking 35 38,40 ± 1,41 38 8,39 BMI 21,64 ± 0,45 22,31 2,68 FVC 3,09 ± 0,05 3,10 0,29 Aerobic Endurance 38,94 ± 0,81 38,20 4,78 From the table above, it can be seen that smoking has an average of 38.40 ± 1.41 with a median value of 38 and a standard deviation of 8.39. BMI has an average of 21.64 ± 0.45 with a median value of 22.31 and a standard deviation of 2.68. FVC had a mean of 3.09 ± 0.05 with a median value of 3.10 and a standard deviation of 0.29. Aerobic endurance had a mean of 38.94 ± 0.81 with a median value of 38.20 and a standard deviation of 4.78. 3.2. Data Normality Test The normality test was carried out using the Shapiro- Wilk test with SPSS. If the p-value is > 0.05, the results indicate that the data are normally distributed. Table 2 shows the results of the data normality test for each variable. Table 2. Data Normality Variable α p-value Smoking 0,05 0,416 BMI 0,345 FVC 0,402 Aerobic Endurance 0,582 From the table above, it can be seen that the smoking variable has a p value of 0.416 > α = 0.05, it can be concluded that the data is normally distributed. BMI has a p value = 0.345 > α = 0.05, it can be concluded that the data is normally distributed. FVC has a p value of 0.402 > α = 0.05, it can be concluded that the data is normally distributed. Aerobic endurance has a p value = 0.582 > α = 0.05, it can be concluded
normally distributed. BMI has a p value = 0.345 > α = 0.05, it can be concluded that the data is normally distributed. FVC has a p value of 0.402 > α = 0.05, it can be concluded that the data is normally distributed. Aerobic endurance has a p value = 0.582 > α = 0.05, it can be concluded that the data is normally distributed. 3.3. Hypothesis Test After testing the requirements of the analysis, namely the normality of the data, it was found that the research variables of smoking, BMI, FVC and aerobic endurance were normally distributed, so the statistical test was continued with a parametric test, namely path analysis using SPSS. There is a significant relationship if the significance value (sig) < α = 0.05. The following are the results of data analysis model 1 path analysis to see the direct relationship between smoking, BMI, and FVC. From table 3 it can be seen that smoking has a sig of 0.460 > α = 0.05, where there is no relationship between smoking and lung vital capacity and smoking has an influence of 1, 68% on lung vital capacity. For BMI has a sig of 0.037 < α = 0.05 where there is a significant relationship between BMI and lung vital capacity and BMI has an influence of 12.82% on lung vital capacity. Simultaneously, smoking and BMI have an impact on lung vital capacity of 14.5% and the remaining 85.5% of other factors are not studied. For more details, see Table 4. Table 3. Model 1 Test Variable (B) t Sig. Constant 2.417 5.292 0.000 Smoking -0.004 -0.747 0,319 BMI 0.039 2.174 0.037 Table 4. Impact of Smoking and BMI on FVC Model R R Square Adjusted R Square Std. Error of the Estimate 1 0.381 a 0,145 0,092 0,28060 The relationship between smoking, BMI, and lung vital capacity to aerobic endurance in the path analysis model 2 can be seen in Table 5. Table 5. Model 2 Test Variable (B) t Sig. Constant 28,454 2,682 0,012 Smoking 0,172 1,755 0,089 FVC 0,314 0,105 0,917 BMI 0,134 0,410
Square Std. Error of the Estimate 1 0.381 a 0,145 0,092 0,28060 The relationship between smoking, BMI, and lung vital capacity to aerobic endurance in the path analysis model 2 can be seen in Table 5. Table 5. Model 2 Test Variable (B) t Sig. Constant 28,454 2,682 0,012 Smoking 0,172 1,755 0,089 FVC 0,314 0,105 0,917 BMI 0,134 0,410 0,684 Data analysis was conducted to see the direct effect of smoking on endurance of 0.303 and the indirect effect of smoking through FVC on endurance of 0.0019, which means that the indirect effect is smaller than the direct effect, which concludes that indirectly smoking through lung vital capacity on endurance does not have a significant effect. Analysis of BMI data through FVC on endurance, obtained direct influence of BMI on endurance of 0.075 and indirect impact of smoking through FVC on endurance of 0.0068, which means the direct effect is greater than the indirect effect. It concludes that indirectly, BMI through
874 The Impact of Smoking, Body Mass Index, and Pulmonary Function on Aerobic Endurance: A Case Study of College Sports Students FVC has no significant effect on endurance. The contribution given by smoking, BMI, and FVC to endurance is 9.5%, and other factors influence the remaining 90.5%. For more details, see Table 6. Table 6. Impact of Smoking, BMI, and FVC on aerobic endurance Model R R Square Adjusted R Square Std. Error of the Estimate 2 0.309 a 0,095 0,008 4,75950 4. Discussion This study aimed to analyse how smoking, Body Mass Index (BMI), and pulmonary function (Forced Vital Capacity ‘FVC’) affect aerobic endurance in sports students at a college with an age of 19,23 ± 0,92 years. From the results of the research that has been conducted, various findings are important in understanding the relationship between these factors and the respiratory health and aerobic fitness of students. This study found that not all variables had a significant relationship with aerobic endurance, although some factors had a certain impact on lung vital capacity. The study indicated that no significant correlation existed between smoking and lung vital capacity, as indicated by a significance value of 0.460 > α = 0.05. Theoretically, smoking can impair lung function by increasing the amount of carbon monoxide in the blood, reducing oxygenation capacity, and causing respiratory tract inflammation [6]. However, according to the results of this study, the sports students who served as participants did not experience a significant impact on their lung vital capacity. This is due to the duration and intensity of smoking, which is still not enough to cause noticeable physiological changes. Smoking is recognised as a major risk factor for various respiratory disorders, including chronic obstructive pulmonary disease (COPD) and reduced lung function [31]. However, the impact of smoking on lung vital capacity is often cumulative and takes a long time to show a noticeable effect [32], [33]. Therefore, the results of this study may indicate that the sports students who were the subjects of the study are still in the early stages of smoking or have a high enough