Supervisors info:
Μαριδάκη Μ., Αναπληρώτρια Καθηγήτρια, ΣΕΦΑΑ, ΕΚΠΑ
Παραδείσης Γ., Επίκουρος Καθηγητής, ΣΕΦΑΑ, ΕΚΠΑ
Φιλίππου Α., Επίκουρος Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Summary:
Carbohydrate ingestion during short duration and high intensity exercise (≤ 1 hour, ˃ 70% VO2max) has shown that has a positive effect on endurance performance (Rollo & Williams, 2011). The mechanisms involved in this effect have not been clarified yet, as there appears to be no metabolic aetiology (i.e. hypoglycaemia), although a potential role of the central nervous system (CNS) has been speculated (Chambers & Jeukendrup, 2010). To study possible improvements in endurance performance without allowing carbohydrates to enter the bloodstream, many researchers have used the technique of rinsing the mouth with a carbohydrate solution (RCHO) instead of swallowing it. All these studies have used men and only two of them have also included a small number of women participants (two each), while all have taken place within a laboratory setting. The aim of this Thesis was to study the effect of RCHO on 1 hour running performance only in women runners. This is the first study that was carried out outside the laboratory and examined athletes in conditions that resemble real-life race, thus increasing its ecological validity. For this purpose, 15 adult female recreational endurance runners were recruited that ran 2 races lasting 1 hour, while familiarization training had been preceded. The 2 races were held within 7 days and while the runners were in the follicular phase (FP) of their regular menstrual cycle, or at any time for the runners who were at menopause. Races took place in a velodrom to allow standard environmental conditions. Following a double-blind process and random order, they were given through a plastic syringe before the initiation of exercise and every 15 minutes 25 ml of either a carbohydrate solution (6.4%) (RCHO) or a Placebo solution (0%) (PR). Runners rinsed the assigned fluid for 5 sec and then expelled it without swallowing. The main finding was that there was no difference in 1 hour running performance, neither by treatment (RCHO: 10621.88 ± 205.98 m vs. RP: 10454.00 ± 206.64 m; mean ± SE, t= 1.784, P= 0.096) nor by race order (1strace: 10549.13 ± 213.67 m vs. 2nd race 10526.75 ± 201.16 m; mean ± SE, t= 0.215, P= 0.833). Additionally, there was no difference between treatments in perceived rate of exertion (P= 0.14) and heart rate (P= 0.06). The results showed that under these conditions and for the participants of the present study, RCHO did not lead in a better 1 hour running performance in comparison to RP.
