Iron, Hematological Parameters and Blood Plasma Lipid Profile in Vitamin D Supplemented and Non-Supplemented Young Soccer Players Subjected to High-Intensity Interval Training

Abstract

Summary Vitamin D deficiency has been associated with increased risk for cardiovascular disease and anemia. Vitamin D-related changes in lipid profile have been studied extensively but the relationship between vitamin D and lipid metabolism is not completely understood. As both vitamin D and intermittent training may potentially affect iron and lipid metabolism, the aim of the study was to evaluate whether a daily supplementation of vitamin D can modulate the response of hematological and lipid parameters to high-intensity interval training (HIIT) in soccer players. Thirty-six young elite junior soccer players were included in the placebo-controlled, double-blind study. Participants were non-randomly allocated into either a supplemented group (SG, n520, HIIT and 5,000 IU of vitamin D daily) or placebo group (PG, n516, HIIT and sunflower oil). Hematological parameters were ascertained before and after the 8-wk training. The change score (post-and pre-training difference) was calculated for each individual and the mean change score (MCS) was compared between SG and PG using the t test and analysis of covariance. There were no differences between SG and PG at baseline. The red and white cell count, hemoglobin, hematocrit, MCHC, ferritin, and HDL-cholesterol changed significantly over the 8-wk HIIT. However, no significant differences in MCS were observed between SG and PG for any variable. A daily vitamin D supplement did not have any impact on alteration in hematological or lipid parameters in young soccer players in the course of high-intensity interval training. Key Words nutrition, athletic training, sport, interval training, intermittent exercise In recent years, vitamin D has been the subject of intensive research with the primary goal of identifying and understanding its roles beyond the bones, such as cancer, immunity, cardiovascular risk, erythropoiesis, muscle function and athletic performance, to name a few (1, 2). Several lines of evidence, observational studies in particular, suggest that vitamin D lowers the risk of cardiovascular disease (3, 4). Numerous mechanistic explanations for this effect are proposed, such as change in insulin resistance, inflammatory reactions, and parathyroid hormone (PTH), renin and blood pressure levels (5). In addition, owing to a well-known relationship between dyslipidemia and atherosclerotic disease as well as a high prevalence of both vitamin D deficiency and cardiovascular disease, vitamin D-dependent changes in lipid profile have recently been given much attention (6). However, the relationship between vitamin D and lipid metabolism is not completely understood (7-10). Moreover, found that genetically reduced plasma 25-hydroxyvitamin D (25(OH)D) is not associated with increased risk of ischemic heart disease. Moreover, the results of Scragg et al.'s (12) randomized controlled trial (RCT) study showed no evidence that monthly high-dose vitamin D supplementation (100,000 IU a month) prevented cardiovascular diseases.In cross-sectional observational studies, lower p-2...

Anserine Reverses Exercise-Induced Oxidative Stress and Preserves Cellular Homeostasis in Healthy Men

“…Area under the curve with high dose anserine (ANS-HD), low dose anserine (ANS-LD), and placebo (PLA) treatments of the following blood biomarkers: Oxidative stress; superoxide dismutase (SOD), catalase (CAT), glutathione disulfide (GSSG), glutathione (GSH), GSH/GSSG ratio, and thiobarbituric acid active reactive substances (TBARS); cell damage; glutamic-oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), creatine kinase myocardial band (CKMB), and myoglobin ( Anserine's potential for augmenting cell damage repair adaptations may have reflected a preserved WBC ( Figure 5). However, RBC levels showed a small but significant increase in MCV (p < 0.01) and a decrease (~1%) in MCHC (p = 0.001) in ANS-HD compared with ANS-LD and PLA ( Figure 6), which is close to previously reported decreased MCHC following either intense exercise training (~1%-3%) [15] or a high intensity exercise training combined with a vitamin D supplement (~0.7%) [26]. Senescent RBCs are particularly prone to exercise-induced intravascular haemolysis and an associated…”

The effect of vitamin D supplementation on hemoglobin concentration: a systematic review and meta-analysis

“…Cholecalciferol was the main form of vitamin D that were supplemented in these studies. The duration of supplementation with vitamin D also varied from 3 h to 6 months [40][41][42][43][44][45][46][47][48][49][50][51][52][53].…”

“…Different types of vitamin D were used in these studies, four studies received vitamin D fortified food with cholecalciferol [40,[46][47][48], eight studies received oral vitamin D (cholecalciferol) supplements [42,44,45,[49][50][51][52][53] and in one study subjects were supplemented with ergocalciferol and another one with calcitriol [41,43]. The minimum vitamin D dosage was 20 IU and maximum was 500,000 IU according to these studies ( Table 1).…”

Vitamin D Supplementation Modestly Reduces Serum Iron Indices of Healthy Arab Adolescents

“…Other clinical trials also found no significant changes in iron indices among healthy adults despite mega-doses of vitamin D3 [24,25]. Jastrzebska and colleagues have even taken into consideration the influence of physical activity and intermittent training since it can potentially affect vitamin D and iron metabolism, yet no significant differences were still found in the hematological parameters (Hb, Hct, and ferritin) of athletes given 5000 IU of vitamin D daily for eight weeks over those who did not receive supplementation [26]. All these previous studies, including the present one, suggest that vitamin D correction is unlikely to improve, if not reduce, iron indices, at least in apparently healthy populations.…”