Institute of Clinical Health and Exercise Sciences, University of the West of Scotland, Blantyre, Scotland.
Institute of Biomedical and Environmental Health Research, University of the West of Scotland, Blantyre, Scotland.
PLoS One. 2020 Dec 15;15(12):e0243755. doi: 10.1371/journal.pone.0243755. eCollection 2020.
There have been recent calls for strategies to improve oral health in athletes. High carbohydrate diets, exercise induced dehydration and transient perturbations to immune function combine to increase oral disease risk in this group. We tested whether a single dose of nitrate (NO3-) would offset the reduction in salivary pH following carbohydrate ingestion before and after an exercise bout designed to cause mild dehydration. Eleven trained male runners ([Formula: see text] 53 ± 9 ml∙kg-1∙min-1, age 30 ± 7 years) completed a randomised placebo-controlled study comprising four experimental trials. Participants ingested the following fluids one hour before each trial: (a) 140 ml of water (negative-control), (b) 140 ml of water (positive-control), (c) 140 ml of NO3- rich beetroot juice (~12.4 mmol NO3-) (NO3- trial) or (d) 140 ml NO3- depleted beetroot juice (placebo-trial). During the negative-control trial, participants ingested 795 ml of water in three equal aliquots: before, during, and after 90 min of submaximal running. In the other trials they received 795 ml of carbohydrate supplements in the same fashion. Venous blood was collected before and after the exercise bout and saliva was sampled before and repeatedly over the 20 min following carbohydrate or water ingestion. As expected, nitrite (NO2-) and NO3- were higher in plasma and saliva during the NO3- trial than all other trials (all P<0.001). Compared to the negative-control, salivary-pH was significantly reduced following the ingestion of carbohydrate in the positive-control and placebo trials (both P <0.05). Salivary-pH was similar between the negative-control and NO3- trials before and after exercise despite ingestion of carbohydrate in the NO3- trial (both P≥0.221). Ingesting NO3- attenuates the expected reduction in salivary-pH following carbohydrate supplements and exercise-induced dehydration. NO3- should be considered by athletes as a novel nutritional strategy to reduce the risk of developing acidity related oral health conditions.
最近有人呼吁采取策略来改善运动员的口腔健康。高碳水化合物饮食、运动引起的脱水和免疫功能的短暂波动会增加这群人的口腔疾病风险。我们测试了在一项旨在引起轻度脱水的运动回合前后，单次摄入硝酸盐（NO3-）是否会抵消碳水化合物摄入后唾液 pH 值的降低。11 名训练有素的男性跑步者（[公式：见文本]53 ± 9 ml·kg-1·min-1，年龄 30 ± 7 岁）完成了一项随机安慰剂对照研究，包括四项实验试验。参与者在每次试验前一小时服用以下液体：（a）140 ml 水（阴性对照），（b）140 ml 水（阳性对照），（c）富含硝酸盐的甜菜根汁 140 ml（~12.4 mmol NO3-）（NO3-试验）或（d）140 ml 耗尽硝酸盐的甜菜根汁（安慰剂试验）。在阴性对照试验中，参与者在 90 分钟的亚最大跑步期间分三次摄入 795 ml 的水。在其他试验中，他们以同样的方式摄入 795 ml 的碳水化合物补充剂。在运动回合前后采集静脉血，并在碳水化合物或水摄入前后 20 分钟内重复采集唾液样本。正如预期的那样，NO2-和 NO3-在血浆和唾液中的含量在 NO3-试验中高于所有其他试验（均 P<0.001）。与阴性对照相比，在阳性对照和安慰剂试验中，碳水化合物摄入后唾液 pH 值明显降低（均 P<0.05）。尽管在 NO3-试验中摄入了碳水化合物，但运动前后负对照和 NO3-试验之间的唾液 pH 值相似（均 P≥0.221）。摄入 NO3-可减轻碳水化合物补充和运动引起的脱水后预期的唾液 pH 值降低。NO3- 应被运动员视为一种新的营养策略，以降低发生与酸度相关的口腔健康状况的风险。
