The effect of aerobic exercise and vitamin D supplementation on inflammatory factors, anti-inflammatory proteins, and lung function in male smokers: A randomized controlled trial
Abstract BackgroundThis study aimed to investigate the effect of aerobic exercise and vitamin D supplementation on inflammation (TNF-α, IL-6, CC16, SP-D, and CC16/SP-D ratio) and lung function (FEV1, FVC, and FEV1/FVC ratio) in male smokers.MethodsAfter applying inclusion criteria, a total of 40 healthy male smokers were recruited in this study. The subjects were randomly divided into four groups as follows: Aerobic Exercise + vitamin D Supplementation (AE + VitD, N = 10), Aerobic Exercise (AE, N = 10), vitamin D Supplementation (VitD, N = 10), and Control (C, N = 10). The subjects in the AE + VitD and AE groups performed aerobic exercise training (running) up to 50% of heart rate (HR) max, three times a week for four weeks. Subjects in AE + VitD and VitD groups received 6000 UI/w vitamin D3 for four weeks. The subjects in control group did not receive any intervention. Serum tumor necrosis factor (TNF)-α, interleukin (IL)-6, Clara cell protein (CC16), surfactant protein (SP)-D, CC16/SP-D ratio, and lung function (FEV1, FVC, and FEV1/FVC ratio) were measured before and after four weeks of intervention.ResultsSerum levels of TNF-α, IL-6, CC16, and SP-D decreased significantly in AE + VitD and AE groups after four weeks (P < 0.05), but serum SP-D level in the AE group did not decrease significantly. In addition, FEV1 and FVC increased significantly (P < 0.05) in AE + VitD and AE groups after four weeks of intervention. However, AE + VitD and AE did not have a significant effect on CC16/SP-D ratio and FEV1/FVC ratio. Furthermore, serum levels of TNF-α, IL-6, and CC16 decreased significantly after vitamin D supplementation (P < 0.05).ConclusionsThe results of present study demonstrates that aerobic exercise combined with vitamin D supplementation can reduce inflammatory factors and anti-inflammatory proteins in the blood and improve lung function after four weeks. Further larger trials with higher sample size and longer duration are suggested to confirm these results.Trial registrationRetrospectively registered. IRCT20180513039637N4. Registration date: 2020/10/20. URL: https://www.irct.ir/search/result?query=IRCT20180513039637N4