Author(s): PRÉCART, C., TIOLLIER, E., GUILHEM, G., RACINAIS, S., KACED, Y., MORIO, C., PISCIONE, J., BROCHERIE, F., COUDERC, A., Institution: DECATHLON, INSEP, CREPS MONTPELLIER, Country: FRANCE, Abstract-ID: 1611

INTRODUCTION:
Internal cooling strategies are widely used and have proven efficiency for mitigating thermal strain in intermittent sports during major events in the heat1-2. However, ice slushy ingestion may reduce sweat rate3 potentially impairing evaporative heat loss. Ice slushy implementation could also induce gastrointestinal discomfort in athletes4. As palatability and sensory properties can modulate thermal perception and tolerance, this study investigated the impact of different ice slushy flavors on physiological, perceptual, and performance responses during cycling repeated-sprint sessions in the heat.
METHODS:
In a crossover design, seventeen world-class female rugby seven players performed three cycling repeated-sprint sessions (three sets of five 6-s sprints; 24-s and 3-min inter-repetition and inter-set recovery, respectively) in the heat (38°C; 43% relative humidity) with ad libitum water and additional 2×150 g (before and mid-session) of either water (CON) or two isocaloric ice slushies: mint syrup (ICE-M) or grape juice (ICE-G). Performance was measured via peak and mean power output (PPO and MPO, respectively), along with sweat rate (SR) and perceptual ratings assessing pleasure, thermal comfort, and gastrointestinal symptoms (GIS).
RESULTS:
Ad libitum water intake was not different between conditions (p>0.69). No significant main effects were found for PPO and MPO (all p>0.37). SR was significantly different between conditions (p=0.03) driven by a lower SR in the ICE-G condition compared to both CON and ICE-M but without post-hoc analysis significances (CON−ICE-G pHolm=0.08; ICE-G−ICE-M pHolm=0.08; CON−ICE-M pHolm=0.69). Regarding perceptual ratings, thermal comfort was significantly higher for ICE-M compared to ICE-G (pHolm<0.01) and CON (pHolm<0.01) but without any effect on pleasure (p=0.43). While immediate post-session GIS showed no significant effects (p=0.14), GIS post-12 h and post-24 h were significantly higher for ICE-G compared to CON (pHolm=0.01; pHolm=0.02, respectively). No post-hoc analysis significances were observed between ICE-M and CON, or between ICE-G and ICE-M (all pHolm>0.12). Paired Hedges’ g visual estimation plots (ΔCON−ICE-G minus ΔCON−ICE-M) highlighted substantial individual variability for pleasure and all GIS time points.
CONCLUSION:
In this study, minty ice slushy appeared to be the optimal choice for improving thermal comfort in the heat. Compared to ad libitum water and grape juice ice slushy, it does not reduce the sweat rate, thus preserving evaporative thermoregulation. It also did not induce gastrointestinal symptoms post-session. These findings guided the strategy selected by the supporting staff for the Olympic Games; however, the high inter-individual variability observed in pleasure and gastrointestinal symptoms highlights the benefit of pre-competition testing before major sporting events.
1. Racinais et al. 2023
2. Katagiri et al. 2025
3. Morris et al. 2016
4. Naito et al. 2022