The study will consist of 3 parts. Firstly, a randomized cross-over design is used for the short distance run and the effects on GD and RP. Secondly, a parallel design is used to study the effects of the drinks on GD and RP during a longer distance run. Thirdly, the gastric emptying tests will be performed in a randomized cross-over design. Participants will be asked to fill in questionnaire on the gastric distress they experience. 40 participants will be enrolled to participate in part 1 and part 2. 10 out of 40 will participate in part 3 of the study.