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Four weeks before competition in the 2023 Marathon des Sables, a 6-stage, ~250 km running event in the Sahara Desert, we examined the effects of a 7-day intake of New Zealand blackcurrant extract (210 mg anthocyanins per day) on 1 h treadmill running-induced physiological and metabolic responses in the heat (~34 °C, relative humidity: ~30%) in non-acclimatized amateur female and male athletes (age: 23, 38 yrs, BMI: 24.2, 28.4 kg·m−2, body fat%: 29.2, 18.8%, V ˙ O2max: 50.1, 52.1 mL·kg−1·min−1). During the 1 h run at 50% V ˙ O2max (speed female: 7.3, male: 7.5 km·h−1), indirect calorimetry was used, and heart rate was recorded at 15 min intervals with core temperature monitoring (0.05 Hz). The 1 h runs took place 3 h after a light breakfast and 2 h after intake of the final dose of New Zealand blackcurrant extract with water allowed ad libitum during the run. The New Zealand blackcurrant extract had no effects on the female athlete. The respiratory exchange ratio (RER) of the female athlete in the non-supplement control condition was 0.77 ± 0.01, indicating an existing ~77% contribution of fat oxidation to the energy requirements. In the male athlete, during 1 h of running, fat oxidation was higher by 21% (p < 0.01), carbohydrate oxidation was 31% lower (p = 0.05), RER was 0.03 units lower (p = 0.04), and core temperature was 0.4 °C lower (p < 0.01) with no differences for heart rate, minute ventilation, oxygen uptake, and carbon dioxide production for the New Zealand blackcurrant condition compared to the non-supplement control condition. Seven-day intake of New Zealand blackcurrant extract (210 mg anthocyanins per day) provided beneficial physiological and metabolic responses during exertional heat stress by 1 h of indoor (~34 °C) treadmill running in a male Marathon des Sables athlete 4 weeks before competition. Future work is required to address whether New Zealand blackcurrant provides a nutritional ergogenic effect for Marathon des Sables athletes during long-duration running in the heat combined with personalized nutrition. [ABSTRACT FROM AUTHOR]

This study assessed the effect of a commercial carbohydrate menthol drink on cycling time trial (TT) performance in hot and humid conditions compared with a carbohydrate only drink. Ten participants (5 women; V̇O2max: 52.3 ± 8.6 mL kg−1 min−1, Peak Power Output: 286 ± 56 W) completed a 40‐min cycling preload (50% V̇O2max) followed by a 15‐min self‐paced TT in hot (∼35°C) and humid (∼54%) conditions on two occasions (double blind, crossover design). Every 10‐min, 85 mL of carbohydrate (CHO; SIS GO Energy, 60 g h−1) or carbohydrate and menthol (CHO + MEN; SIS Turbo+ 60 g h−1, 0.01% menthol) was swilled (∼10‐s) and ingested. Rectal temperature (Trec) and heart rate (HR) were recorded throughout. Thermal sensation (TS), thermal comfort (TC) and rating of perceived exertion (RPE) were recorded every 5‐min. Taste and aftertaste were rated from very pleasant (+5) to very unpleasant (−5). TT performance (total work; kJ) was similar between CHO (153 kJ [95% CI: 129–177 kJ]) and CHO + MEN (151 kJ [128–178 kJ]). During preload exercise, Trec increased by ∼0.9°C and was similar at the end of the TT (∼38.20°C). Mean preload HR was ∼140 b min−1 in each condition and reached ∼177 b min−1 at the end of the TT. TC was rated as 'much too warm' and TS rated as 'very hot' in both conditions. Both conditions were 'extremely hard' (end point RPE ∼19). All participants preferred the taste and aftertaste of the CHO drink. The commercial carbohydrate menthol drink offered no additional ergogenic benefit compared to a carbohydrate only drink during cycling exercise performed in hot and humid conditions. Highlights: The addition of menthol to a carbohydrate drink had no effect on 15‐min time trial performance.The addition of menthol to a carbohydrate drink had no effect on thermal perceptual measures or physiological measures.Taste and aftertaste perceptions were favourable towards the carbohydrate drink compared to the carbohydrate‐menthol drink. [ABSTRACT FROM AUTHOR]