The effect of vitamin D supplementation during resistance training on the markers of systemic inflammation in untrained males

Physical activity has a dual effect on inflammation. Different studies have showed very contradictory results. The present study was designed to investigate the effects of vitamin D supplementation during 8 weeks of resistance training (RT) on IL-6, TNF- α and CRP concentrations.
Material and In this semi experimental study 20 healthy, sedentary men were randomly divided into two groups [(RT-Vitamin D, n = 10) and (RT-placebo, n=10)]. In order to determine IL-6, TNF- α and CRP concentrations, fasting venous blood samples were obtained before and after 8 weeks of supplementation.
Resistance training (RT) was performed with increasing intensity every other day (3 sessions per week) for 8 weeks. Intensity of RT increased by 5% every week. During 8 weeks, RT-vitamin D group received one dose of vitamin D (50000 IU) every 2 weeks until the end of the training sessions.
Statistical analysis revealed significant decrease in the contractions of IL-6 and TNF- alpha in RT-D supplementation group after training compared to the pretest stage (P≥0/05).
The same results were also found in RT- placebo group (P≥0/05), while CRP was not affected by RT- Vitamin D (P˃0/05). However, with time, vitamin D alone had a significant effect on TNF-alpha (P≥0/05).
Progressive resistance exercise (PRE) can decrease systemic inflammation (SI) indices in the healthy men with normal body fat percentage, although the combination of vitamin D and resistance training can selectively affect systemic inflammation and decrease the levels of these indices.