Table 2.

General characteristics of the studies included in the review.

Reference	Event	Distance/Elevation Gain Temperature	Participants
			N (M + F) (Age)	Experience
Ultra-Trail
Lavoué et al., 2020 [3]	Albi, France	24 h/ (distance range 133–272 km) 11.9–35.1 °C	11 (5 M + 6 F) (46 ± 7 years)	Elite
Wardenaar et al., 2018 [5]	Sixty of Texel, Netherlands	120 km/4.3–9.6 °C	5 M (47 ± 6 years)	Completed at least 10 (ultra) marathons
Martínez et al., 2018 [29]	Ultra Mallorca Serra de Tramuntana, Spain	112 km/ 4.448 m of ascent 11–21 °C	54 (53 M + 1 F) (35.7 ± 7.9 years)	Data not shown
		67 km/2521 m of ascent 11–21 °C	109 (98 M + 11 F) (35.2 ± 8.4 years)
Wardenaar et al., 2015 [6]	Sixty of Texel, Netherlands	120 km/2.2 °C	8 (7 M + 1 F) (46.6 ± 6.3 years)	Data not shown
		60 km/2.2 °C	60 (48 M + 12 F) (46.5 ± 7.2 years)
Costa et al., 2014 [8]	Glenmore 24 Trail Race, Scottish Highlands, Scotland, UK	24 h/(distance range: 122–208 km) 0–20 °C	25 (19 M + 6 F) (39 ± 7 years)	Data not shown
Kruseman et al., 2005 [33]	Tour des Dents du Midi race, Switzerland	44 km/2890 m of ascent 18–30 °C	42 (39 M + 3 F) (42 ± 9.7 years)	Completed at least 10 trail marathons
Trail Marathon
Urdampilleta et al., 2020 [2]	Oiartzun, Spain	10 °C/Cumulative elevation gain: 3980.80 m	20 M LOW: 37.8 ± 9.4 years CON: 37.2 ± 5.4 years EXP: 38 ± 6.8 years	5 years in SOUT (2 World champions)
Viribay et al., 2020 [4]	Oiartzun, Spain	10 °C/Cumulative elevation gain: 3980.80 m	20 M LOW: 37.8 ± 9.4 years CON: 37.2 ± 5.4 years EXP: 38 ± 6.8 years	5 years in SOUT (2 World champions)
Martínez et al., 2018 [29]	Ultra Mallorca Serra de Tramuntana, Spain	11.0–21.6 °C/1424 m of ascent	63 (51 M + 12 F) (36.6 ± 8 years)	Unshown data

M: males; F: females; LOW: 60 g/h of carbohydrate intake during the marathon; CON: 90 g/h of carbohydrate intake during the marathon; EXP: 120 g/h of carbohydrate intake during the marathon; #: average.