Improvement in blood pressure after short-term inorganic nitrate supplementation is attenuated in cigarette smokers compared to non-smoking controls

Dietary supplementation with inorganic nitrate (NO3-) has been reported to improve cardiovascular health indices in healthy adults. Cigarette smoking increases circulating thiocyanate (SCN-), which has been suggested to competitively inhibit salivary nitrate (NO3-) uptake, a rate-limiting step in dietary NO3 - metabolism. Therefore, this study tested the hypothesis that dietary NO3 - supplementation would be less effective at increasing the circulating plasma nitrite concnetration ([NO2-]) and lowering blood pressure in smokers (S)compared to non-smokers (NS). Nine healthy smokers and eight healthy non-smoking controls reported to the laboratory at baseline (CON) and following six day supplementation periods with 140 ml∙day-1 NO3--rich (8.4 mmol NO3 -∙day-1; NIT) and NO3--depleted (0.08mmol NO3 -∙day-1; PLA) beetroot juice in a cross-over experiment. Plasma and salivary [SCN-] were elevated in smokers compared to non-smokers in all experimental conditions (P<0.05). Plasma and salivary [NO3 -] and nitrite ([NO2-]) were elevated in the NIT condition compared to CON and PLA conditions in smokers and non-smokers (P<0.05). However, the change in salivary [NO3-] (S: 3.5 ± 2.1 vs. NS: 7.5 ± 4.4 mM), plasma [NO3-] (S: 484 ± 198 vs. NS: 802 ± 199 μM) and plasma [NO2-] (S: 218 ± 128 vs. NS: 559 ± 419 nM) between the CON and NIT conditions was lower in the smokers compared to the non-smokers (P<0.05). Salivary [NO2 -] increased above CON to a similar extent with NIT in smokers and nonsmokers (P>0.05). Systolic blood pressure was lowered compared to PLA with NIT in nonsmokers (P0.05). These findings suggest that dietary NO3- metabolism is compromised in smokers leading to an attenuated blood pressure reduction compared to non-smokers after NO3- supplementation. These observations may provide novel insights into the cardiovascular risks associated with cigarette smoking and suggest that this population may be less likely to benefit from improved cardiovascular health if they increase dietary NO3 - intake

Influence of iodide ingestion on nitrate metabolism and blood pressure following short-term dietary nitrate supplementation in healthy normotensive adults

Uptake of inorganic nitrate (NO3−) into the salivary circulation is a rate-limiting step for dietary NO3− metabolism in mammals. It has been suggested that salivary NO3− uptake occurs in competition with inorganic iodide (I−). Therefore, this study tested the hypothesis that I− supplementation would interfere with NO3− metabolism and blunt blood pressure reductions after dietary NO3− supplementation. Nine healthy adults (4 male, mean ± SD, age 20 ± 1 yr) reported to the laboratory for initial baseline assessment (control) and following six day supplementation periods with 140 mL·day−1 NO3−-rich beetroot juice (8.4 mmol NO3−·day−1) and 198 mg potassium gluconate·day−1 (nitrate), and 140 mL·day−1 NO3−-rich beetroot juice and 450 μg potassium iodide·day−1 (nitrate + iodide) in a randomized, cross-over experiment. Salivary [I−] was higher in the nitrate + iodide compared to the control and NIT trials (P 0.05). Systolic blood pressure was lower than control (112 ± 13 mmHg) in the nitrate (106 ± 13 mmHg) and nitrate + iodide (106 ± 11 mmHg) trials (P 0.05). In conclusion, co-ingesting NO3− and I− perturbed salivary NO3− uptake, but the increase in salivary and plasma [NO2−] and the lowering of blood pressure were similar compared to NO3− ingestion alone. Therefore, increased dietary I− intake, which is recommended in several countries worldwide as an initiative to offset hypothyroidism, does not appear to compromise the blood pressure reduction afforded by increased dietary NO3− intake

Two weeks of watermelon juice supplementation improves nitric oxide bioavailability but not endurance exercise performance in humans

This study tested the hypothesis that watermelon juice supplementation would improve nitric oxide bioavailability and exercise performance. Eight healthy recreationally-active adult males reported to the laboratory on two occasions for initial testing without dietary supplementation (control condition). Thereafter, participants were randomly assigned, in a cross-over experimental design, to receive 16 days of supplementation with 300 mL·day-1 of a watermelon juice concentrate, which provided ~3.4g L-citrulline·day-1 and an apple juice concentrate as a placebo. Participants reported to the laboratory on days 14 and 16 of supplementation to assess the effects of the interventions on blood pressure, plasma [Lcitrulline], plasma [L-arginine], plasma [nitrite], muscle oxygenation and time-to-exhaustion during severe-intensity exercise. Compared to control and placebo, plasma [L-citrulline] (29 ± 4, 22 ± 6 and 101 ± 23 μM), [L-arginine] (74 ± 9, 67 ± 13 and 116 ± 9 μM) and [nitrite] (102 ± 29, 106 ± 21 and 201 ± 106 nM) were higher after watermelon juice supplementation (P<0.01). However, systolic blood pressure was higher in the watermelon juice (130 ± 11) and placebo (131 ± 9) conditions compared to the control condition (124 ± 8 mmHg; P<0.05). The skeletal muscle oxygenation index during moderate-intensity exercise was greater in the watermelon juice condition than the placebo and control conditions (P<0.05), but time-to-exhaustion during the severe-intensity exercise test (control: 478 ± 80, placebo: 539 ± 108, watermelon juice: 550 ± 143 s) was not significantly different between conditions (P<0.05). In conclusion, while watermelon juice supplementation increased baseline plasma [nitrite] and improved muscle oxygenation during moderate-intensity exercise, it increased resting blood pressure and did not improve time-to-exhaustion during severe-intensity exercise. These findings do not support the use of watermelon juice supplementation as a nutritional intervention to lower blood pressure or improve endurance exercise performance in healthy adults

Discrete physiological effects of beetroot juice and potassium nitrate supplementation following 4 weeks sprint interval training

The physiological and exercise performance adaptations to sprint interval training (SIT) may be modified by dietary nitrate (NO3-) supplementation. However, it is possible that different types of NO3- supplementation evoke divergent physiological and performance adaptations to SIT. The purpose of this study was to compare the effects of 4 weeks SIT with and without concurrent dietary NO3- supplementation administered as either NO3--rich beetroot juice (BR) or potassium NO3- (KNO3). Thirty recreationally-active subjects completed a battery of exercise tests before and after a 4 week intervention in which they were allocated to one of three groups: 1) SIT undertaken without dietary NO3- supplementation (SIT); 2) SIT accompanied by concurrent BR supplementation (SIT+BR); or 3) SIT accompanied by concurrent KNO3 supplementation (SIT+KNO3). During severe-intensity exercise, VO2peak and time to task failure were improved to a greater extent with SIT+BR than SIT and SIT+KNO3 (P0.05). These findings indicate that 4 weeks SIT with concurrent BR supplementation results in greater exercise capacity adaptations compared to SIT alone and SIT with concurrent KNO3 supplementation. This may be the result of greater NO-mediated signalling in SIT+BR compared to SIT+KNO3

Информатизация в системе управления персоналом в таможенных органах

Работа направлена на исследование информационных систем управления персоналом таможенных органов на примере Томской таможни, а также изучение современного программного обеспечения, которое позволяет оптимизировать процессы кадрового менеджмента. В процессе исследования рассматривался процесс модернизации управления персоналом в таможенных органах. Охарактеризованы изменения, связанные с внедрением информационных систем в данную сферу. В результате исследования были выявлены те аспекты управления персоналом, в которых информатизация может оказаться наиболее эффективной. Предложены мероприятия по совершенствованию информатизации управления персоналом в таможенных органах.The work is aimed at the study of information systems for personnel management of customs authorities on the example of the Tomsk Customs, as well as the study of modern software that allows to optimize the processes of personnel management. In the process of research, the process of modernization of personnel management in customs bodies was considered. The changes connected with the introduction of information systems in this sphere are characterized.  As a result of the research, those aspects of personnel management were revealed, in which informatization can be most effective. Measures are proposed to improve informatization of personnel management in customs bodies

Lowering of blood pressure after nitrate-rich vegetable consumption is abolished with the co-ingestion of thiocyanate-rich vegetables in healthy normotensive males

A diet rich in vegetables is known to provide cardioprotection. However, it is unclear how the consumption of different vegetables might interact to influence vascular health. This study tested the hypothesis that nitrate-rich vegetable consumption would lower systolic blood pressure but that this effect would be abolished when nitrate-rich and thiocyanate-rich vegetables are co-ingested. On four separate occasions, and in a randomised cross-over design, eleven healthy males reported to the laboratory and consumed a 750 mL vegetable smoothie that was either: low in nitrate (~ 0.3 mmol) and thiocyanate (~ 5 μmol), low in nitrate and high in SCN- (~ 72 μmol), high in nitrate (~ 4 mmol) and low in SCN- and high in nitrate and SCN-. Blood pressure as well as plasma and salivary [thiocyanate], [nitrate] and [nitrite] were assessed before and 3 hours after smoothie consumption. Plasma [nitrate] and [nitrite] and salivary [nitrate] were not different after consuming the two high-nitrate smoothies, but salivary [nitrite] was higher after consuming the high-nitrate low-thiocyanate smoothie (1183 ± 625 µM) compared to the high-nitrate high-thiocyanate smoothie (941 ± 532 µM; P<0.001). Systolic blood pressure was only lowered after consuming the high-nitrate low-thiocyanate smoothie (-3 ± 5 mmHg; P<0.05). The acute consumption of vegetables high in nitrate and low in thiocyanate lowered systolic blood pressure. However, when the same dose of nitrate-rich vegetables was co-ingested with thiocyanate-rich vegetables the increase in salivary [nitrite] was smaller and systolic blood pressure was not lowered. These findings might have implications for optimising dietary guidelines aimed at improving cardiovascular health

Dynamics of the power-duration relationship during prolonged endurance exercise and influence of carbohydrate ingestion

We tested the hypotheses that the parameters of the power-duration relationship, estimated as the end-test power (EP) and work done above EP (WEP) during a 3-min all-out exercise test (3MT), would be reduced progressively after 40 min, 80 min, and 2 h of heavy-intensity cycling and that carbohydrate (CHO) ingestion would attenuate the reduction in EP and WEP. Sixteen participants completed a 3MT without prior exercise (control), immediately after 40 min, 80 min, and 2 h of heavy-intensity exercise while consuming a placebo beverage, and also after 2 h of heavy-intensity exercise while consuming a CHO supplement (60 g/h CHO). There was no difference in EP measured without prior exercise (260 ± 37 W) compared with EP after 40 min (268 ± 39 W) or 80 min (260 ± 40 W) of heavy-intensity exercise; however, after 2 h EP was 9% lower compared with control (236 ± 47 W; P < 0.05). There was no difference in WEP measured without prior exercise (17.9 ± 3.3 kJ) compared with after 40 min of heavy-intensity exercise (16.1 ± 3.3 kJ), but WEP was lower (P < 0.05) than control after 80 min (14.7 ± 2.9 kJ) and 2 h (13.8 ± 2.7 kJ). Compared with placebo, CHO ingestion negated the reduction of EP following 2 h of heavy-intensity exercise (254 ± 49 W) but had no effect on WEP (13.5 ± 3.4 kJ). These results reveal a different time course for the deterioration of EP and WEP during prolonged endurance exercise and indicate that EP is sensitive to CHO availability

Neither beetroot juice supplementation nor increased carbohydrate oxidation enhance economy of prolonged exercise in elite race walkers

Given the importance of exercise economy to endurance performance, we implemented two strategies purported to reduce the oxygen cost of exercise within a 4 week training camp in 21 elite male race walkers. Fourteen athletes undertook a crossover investigation with beetroot juice (BRJ) or placebo (PLA) [2 d preload, 2 h pre-exercise + 35 min during exercise] during a 26 km race walking at speeds simulating competitive events. Separately, 19 athletes undertook a parallel group investigation of a multi-pronged strategy (MAX; n = 9) involving chronic (2 w high carbohydrate [CHO] diet + gut training) and acute (CHO loading + 90 g/h CHO during exercise) strategies to promote endogenous and exogenous CHO availability, compared with strategies reflecting lower ranges of current guidelines (CON; n = 10). There were no differences between BRJ and PLA trials for rates of CHO (p = 0.203) or fat (p = 0.818) oxidation or oxygen consumption (p = 0.090). Compared with CON, MAX was associated with higher rates of CHO oxidation during exercise, with increased exogenous CHO use (CON; peak = ~0.45 g/min; MAX: peak = ~1.45 g/min, p < 0.001). High rates of exogenous CHO use were achieved prior to gut training, without further improvement, suggesting that elite athletes already optimise intestinal CHO absorption via habitual practices. No differences in exercise economy were detected despite small differences in substrate use. Future studies should investigate the impact of these strategies on sub-elite athletes’ economy as well as the performance effects in elite groups