Author(s) and publication year | Study design | Data collection | Setting | Number of participants (n) | Age (years) | Sex | BMI (kg/m2) | Quality and LoE |
Buckler and Higgins (2000)22 | Observational race report | Medical encounters prospectively recorded at baseline and during the race. | Tibet: 1999 Everest Marathon Altitude range: 5184–3446 m Temperature: −10°C and below | 70 | Not reported | Not reported | Not reported | Quality 5/15 LoE 4 |
Costa et al (2016)23 | Event 1: MSUM Prospective Event 2: Cross-sectional | Event 1: MSUM prospective data collected over 4 days Event 2: continuous marathon (24 hours) Cross-sectional data collected at the end of the 24 hours race | Event 1 (Spain) MSUM: Al Andalus Ultimate Trail (2010 and 2011) Event 2 (Scotland) 24 hours continuous ultramarathon: Glenmore24 Trail Race (2011 and 2012) | Event 1: MSUM 54 Event 2: Continuous marathon (24 hours) 22 | Event 1: MSUM 40 (±8) Event 2: Continuous marathon (24 hours) 40 (±7) | Event 1: MSUM men: n=33 (61%); women: n=21 (39%) Event 2: continuous marathon (24 hours): men: n=16 (73%); women: n=6 (27%) | Not reported | Quality 11/15 LoE 2b |
Dawadi et al (2020)24 | Retrospective descriptive | Medical encounters | Nepal: Manaslu trail race: 7 day stage race: 212 km High altitude | 100 2014: 34 2015: 26 2016: 40 | Not reported | Men: n=60 (60%) women: n=40 (40%) | Not reported | Quality 12/15 LoE 4 |
Garcia-Malinis et al (2020)34 | Cross-sectional | Self-reported questionnaires | Spain: Ultra-trail race (GranTrail Aneto-Posets) 105 km | 657 | 39.7±7.9 | Men: n=474 (72.1%) women: n=183 (27.9%) | Not reported | Quality 10/15 LoE 2b |
Gonzales-Lazaro et al (2021)11 | Retrospective cohort study | Self-reported participant form recording injuries sustained during the race. | Spain: mountain races (n=36) Mean distance: 28±6 km (95% CI, 26 to 30). Mean accumulative elevation change: 3497±717 m (3254–3740). Minimum temperature: 7°C±5°C (5–9). Maximum temperature: 23°C±7°C (20–25) | 4831 | 40±7 (18–72) | Men: 91% women: 9% | Not reported | Quality 9/15 LoE 4 |
Graham et al (2012)6 | Observational | Injuries clinically diagnosed (daily recorded via a standardised injury reporting form). | New Zealand: 2009 Gobi Challenge, 7 stage desert race ultramarathon with a total of 150 miles (240 km). | 11 one below knee amputee | 33±11 Amputee age: 43 | Men: n=11 (100%) women: n=0 (0%) | 24±1.8 Amputee: 25 | Quality 8/15 LoE 2b |
Graham et al (2021)25 | Prospective cohort | Medical encounters recorded over 3 days during the race. | Yukon, Canada: 6633 Ultra: 120 miles (192 km) ran over 3 days; Minimum temperature: −20°C | 12 | 42±5.4 years. | Men: n=9 (75%) women: n=3 (25%) | Not reported | Quality 11/15 LoE 2b |
Hoffman and Stuempfle (2015)27 | Observational | Self-reported symptoms of muscle cramping recorded with online questionnaire post-race. | USA, California: 2014 Western States Endurance Run 161 km (100 miles) | 280 | Not reported | Not reported | Not reported | Quality 13/15 LoE 2b |
Krabak et al (2011)7 | Observational | Medical encounters: data recorded daily over a 7 day period, during each race at a medical checkpoint (every 10 km and finish line) | 4 Ultramarathons (240 km) (7 day stage race) Gobi Desert, China: 2005 and 2006 Sahara Desert, Egypt: 2005 Atacama Desert, Chile: 2006 | 396 | 40 (±10.6) (18-64) | Men: n=314 (79.2%) women: n=82 (20.8%) | 23.9±3.5 | Quality 12/15 LoE 2b |
McGowan and Hoffman (2015)29 | Observational | Race-day medical encounters. Data collected at the 2010–2013 races. 2010–2011: data collected only at the race finish line. Medical encounters: 2012–2013: data collected at all the race medical stations. | USA, California: Western States Endurance Run 161 km (100 miles) 5500 m ascent, 7000 m descent Maximum altitude: 2667 m; temperatures (min–max): 2010: 3°C–33°C; 2011: 0°C–28°C; 2012: 9°C–22°C; 2013: 5°C–39°C 30 hours cut of time, 24 aid stations | 1563 | 2010: 43±10 (18-75); 2011: 43±10 (22-74); 2012: 42±10 (23-77); 2013: 42±10 (22-70) | 2010— men: n=337 (79.7%) 2011— men: n=305 (81.3%) 2012 Males: n=313 (81.9%) 2013— men: n=306 (79.9%) | Not reported | Quality 8/15 LoE 2b |
Scheer and Murray (2011)30 | Prospective observational | Clinical encounters; data were recorded on a standard form | Spain: 2010 Al Andalus Ultra Trail Ultramarathon 5 day stage race (219 km) | 69 | Males: 46 (27-63) Females: 40 (25–50) | Men: n=48 (70%); women: n=21 (30%) | Not reported | Quality 10/15 LoE 4 |
Scheer et al (2014)31 | Prospective observational | Data collected after each stage race through a direct interview technique using a standardised questionnaire on blisters | Spain: 2010 & 2011: Al Andalus Ultra Trail Ultramarathon 5 day stage race (219 km) Temperature: 32°C–40°C Humidity:32%–40%. | 50 | Men: 40.4±8.3 Women: 40.4±7.5 | Men: n=30 (60%) women: n=20 (40%) | Males: 24.5±1.9; Females: 21.3±2.2 | Quality 12/15 LoE 2b |
Vernillo et al (2016)32 | Cross-sectional | Medical encounter: data recorded at the end of the race. | Trento, Italy: Vigolana Trail Run (65 km) | 77 | 43.6 (±10.9) | Men: n=64 (83%); women: n=13 (17%) | Not reported | Quality 11/15 LoE 4 |
LoE, level of evidence; MSUM, multistage ultramarathon.