Pro Inflammatory Cytokines in Smokers and Non‐Smokers Following Different Intensity of Exercises

Purpose The purpose of the study was to examine changes in C‐reactive protein (CRP) and TNF‐a in blood before and after exercise at different intensities in smokers compared to non‐smokers. Methods Fourteen physically inactive smokers (SM, n =7) and non‐smokers (NS, n =7) aged 18 to 26 were recruited. Each subject completed three treadmill runs at different intensities in a random order (60%, 70%, and 80% of VO 2max ). Running distance for all three runs was equivalent to 30‐min run at 70% VO 2max . Plasma samples were collected at rest (PRE), immediately after (POST), and 1 h following (1H) each run to measure CRP and TNF‐a. Data was analyzed using two‐way repeated measures ANOVA with P<0.05. Results SM had greater values of CRP than NS at POST following 70% (3.3±.3mg/L vs. 2.5±.1, Mean ± SE , P=.014) and 80% (3.9±.3 vs. 3.0±.3, P=.005) VO 2max runs. CRP at POST increased relative to intensity in SM (60% < 70% < 80%, P<0.05), but not in NS (only 60% < 80%, P<0.027). TNF‐α was higher in SM at all measurements points (P=.015). TNF‐α at POST elevated above PRE at 60% (40.4±2.1mg/L vs. 52.4±4.2, P=.028), 70% (41.7±3.3 vs. 56.3±5.6, P=.019), and 80% (39.8±3.3 vs. 57.8±6.1, P=.023) VO 2max runs in SM and 70% (27.9±3.1 vs. 34.3± 4.4, P=.041) and 80% (28.8±3.8 vs. 35.3±2.9, P=.033) VO 2max runs in NS. Conclusion Results indicate SM having higher levels of inflammation even at rest as compared to NS, suggesting higher risk of cardio vascular disease. To exercise intensity CRP and TNF‐a elevate both groups. However, SM responded more sensitively to relatively equal intensity of exercise. These greater elevation in CRP and TNF‐α at POST suggest that high intensity aerobic exercise may be avoided in SM at least in the beginning phase of exercise training.