International Journal of Environmental Research and Public Health

Case Report Right Knee—The Weakest Point of the Best Runners of the World? A Case Study

Robert Gajda 1,* , Paweł Walasek 2 and Maciej Jarmuszewski 3

1 Center for Sports Cardiology, Gajda-Med Medical Center in Pułtusk, 06-100 Pułtusk, 2 Traumatology and Orthopedic Department, Bielanski City Hospital, 01-809 Warszawa, Poland; [email protected] 3 Luxmed Diagnostic, 01-809 Warszawa, Poland; [email protected] * Correspondence: [email protected]; Tel.: +48-604286030

 Received: 24 June 2020; Accepted: 10 August 2020; Published: 17 August 2020 

Abstract: The impact of (UM) on the organs, especially in professional athletes, is poorly understood. We tested a 36-year-old UM male runner before and after winning a 24-h . The primary goal of the study was cardiovascular assessment. The athlete experienced right knee pain for the first time after 12 h of (approximately 130 km), which intensified, affecting his performance. The competitors ran on a 1984 m rectangle-loop (950 42 m) in an atypical × clockwise fashion. The winner completed 516 rectangular corners. Right knee Magnetic Resonance Imaging (MRI) one day after the run showed general overload in addition to degenerative as well as specific features associated with “turning to the right”. Re-examination after three years revealed none of these findings. Different kinds of overloading of the right lower limb, including right knee pain, were indicated in 6 of 10 competitors from the top 20, including a woman who set the world record. The affected competitors suggested as cause for discomfort the shape of the loop and running direction. They believed that changing the direction of the run during the competition and an athletics stadium loop shape on a 2000–2500 m length is better for 24-h UM runners. In the absence of technical alternatives, the “necessary evil” is a counterclockwise run (also Association of Athletics Federations IAAF recommendation). Results suggest that a one-way, clockwise, 24-h UM run had an adverse effect on the athlete’s right knee, as a result of unsymmetrical load. Organizers of 24-h UM runs should consider the shape of the competition loop and apply the principle of uniform load on the musculoskeletal system (alternate directions run). In case of technical impossibility, it would be better to run counterclockwise, which is more common, preferred by runners, and recommended by the IAAF.

Keywords: clockwise run; counter-clockwise run; 24-h ultramarathon run; knee injury; endurance sports; 24-h UM

1. Introduction Ultramarathon (UM) races (distance longer than 41,195 m) are a significant challenge for the competitors’ organism. Preparations for these races take years, and often crown a runner’s career. Overload injuries of the musculoskeletal system due to grueling training is highly probable, and often results in the inability to start the race for which the athlete has prepared for years. It is not uncommon for an overload injury to end a runner’s career. Competitors can train to minimize the probability of injury using various training stimuli, rehabilitation, or avoiding repetitive movements. This special attention to training may be insufficient for the safe completion of a 24-h (24H) race if it takes place, for example, on a rectangular loop and in one direction. This was the case during the 24H race in the Polish Championships. Six of the top 10 competitors reported right knee pain, probably due to taking

Int. J. Environ. Res. Public Health 2020, 17, 5955; doi:10.3390/ijerph17165955 www.mdpi.com/journal/ijerph Int. J. Environ. Res. Public Health 2020, 17, 5955 2 of 11 several hundred rectangular turns to the right. Two of the world’s leading UM runners participated in the run, and both experienced similar pain. Fortunately, their overload injuries did not end their careers. However, such a situation requires an assessment of the impact of such organized races on the competitors’ health, and indicates the necessity and impact of this study. Conducting sport competitions, especially long street runs, is a challenge for organizers, both because of the need to ensure the accuracy and indisputability of the results, and also because of competitors’ safety. In the case of 24-h runs, there is also a need for accommodation for teams taking care of competitors (coaches, masseurs, physiotherapists, chefs, and others) and the audience itself. The best competitors in the 24-h UM run distances of 250 to 300 km [1]. Since time but not distance is predetermined and it is impossible to predict where competitors will finish the race, usually such competitions take place on loops of different lengths and shapes. These loops have a relatively small range of lengths: from a typical athletics track of 400 m to 1–2 miles [1]. It depends not only on organizational capabilities but also on athletes’ preferences and the need for frequent technical support (preferably at least every 2.5 km). The mental sense of security and the ease of controlling the competition course on a shorter loop are also relevant. Different sports competitions have competitors running in different directions. Often, the organizers change the running direction, for example in the Taipei 24-h UM run (treadmill 400 m, changing the running direction every 4 h) [2]. However, loop shapes are mainly dependent on technical capabilities, from extremely uncomfortable with turns at a 180-degree angle, to routes running on different surfaces (dirt ground) with slight slopes [3]. Organizers often forget that loop shape not only affects the final score but also the athlete’s health during the run and regeneration afterwards. To date, there are not many reports on the impact of UM on athletes’ knees, and none describing the impact of running direction and loop shape. Our case study is an example of a leading UM world runner, who during the competition struggled not only with rivals but also with progressive pain in the right knee. Because the athlete did not use heart rate monitors during the 24-h UM, we could not judge how the growing pain affected his speed and or his intensity of effort at each stage of the competition [4,5]. Similar discomfort has been reported by a number of leading athletes, which inspired us to conduct an interview regarding not only pain after the run but also technical preferences (loop length and running direction) for 24-h UM runs.

2. Materials and Methods

2.1. Sports Biography and Main Achievements The UM runner was 36 years old on the day of the competition (height: 1.73 m, weight: 63 kg, body mass index: 21.05 kg/m2). Despite a sedentary job working Monday to Friday from 8:00 h to 16:00 h, he had been running regularly for 20 years and had run approximately 100,000 km. For the last year, his daily training consisted of an average of 22 km/day from Monday to Friday and about 37 km on weekend days. He also swims and goes to the gym for cross-training. This athlete has participated in approximately 50 UMs, the longest of which was a 48-h run. So far, he has never been injured or seriously ill. A two-time Polish Champion in the 24-h UM and winner of the Spartathlon in Greece (2016, 246 km), he also holds numerous other honors. In 2014, he set the Polish record for 12-h races (145.572 km) and has participated four times in the 24-h UM World Championships, winning a medal each time. In 2019, he won the 48-h race in Athens (362 km). All his achievements are on the official website of Ultra Marathon Statistics [6].

2.2. Anamnesis and Information from Other Competitors Wecollated information on post-race pain and preferred lengths, loop shapes, and running direction from 10 athletes in the top twenty of the 24-h UM run who freely agreed on providing such information either directly after the race, or via subsequent e-mail correspondence and telephone conversations. Int. J. Environ. Res. Public Health 2020, 17, 5955 3 of 11 Int. J. Environ. Res. Public Health 2020, 17, x 3 of 10

2.3. Methods Methods The athlete tapered his training (i.e., gradually reduced exercise over a short period of time and TheInt. J. athleteEnviron. Res. tapered Public Health his training2020, 17, x (i.e., gradually reduced exercise over a short period of3 time of 10 and then stopped completely before the the competition) two two weeks before start of the 24 24-h‐h UM. The run started2.3. at Methods 12:00 AM on 8 April 2017. The The competitors ran ran on on a 1984 m asphalt loop in a clockwise fashion. The loop was a 950 m by 42 m rectangle (Figures1 and2). Our study subject ran 129 loops fashion. TheThe loopathlete was tapered a 950 his m training by 42 m (i.e., rectangle gradually (Figures reduced 1 exercise and 2). over Our a study short periodsubject of ran time 129 and loops and performed then stopped 516 completely rectangular before turns. the Oncompetition) On one one of of the the two straight weeks beforesections, start there there of the was 24 ‐a h tent UM. in The which run the athletestarted could at stop 12:00 for AM a meal, on 8 April a short 2017. rest, The and competitors basic hygiene. ran on After a 1984 12 m h, asphalt he stopped loop in for a 12–15clockwise min for a warmfashion. meal, The a changeloop was of a shoes,950 m by and 42 otherm rectangle hygienichygienic (Figures activities. 1 and 2).In Ouraddition, study subjecthe used ran the 129 toilet loops three timesand (2–3(2–3 performed min min each). each). 516 He rectangularHe ate ate and and ingested turns. ingested On liquids one liquidsof along the straight along the run. sections,the The run. weather there The was weather conditions a tent in conditions which are presented the are presentedin Tableathlete1. in could Table stop 1. for a meal, a short rest, and basic hygiene. After 12 h, he stopped for 12–15 min for a warm meal, a change of shoes, and other hygienic activities. In addition, he used the toilet three times (2–3 min each). He ate and ingested liquids along the run. The weather conditions are presented in Table 1.

FigureFigure 1. TheThe 1. The loop loop loop on on on which which which 24 24-h 24‐h‐h ultramarathon ultramarathon run run took took place place (Google (Google Maps). Maps).

FigureFigure 2. Asphalt 2. Asphalt surface surface on on which which the the race race tooktook place.place. In In the the photo: photo: winners winners of the of themen’s men’s and and women’s categories just before the final whistle. women’sFigure 2. categoriesAsphalt surface just before on which the final the whistle. race took place. In the photo: winners of the men’s and women’s categories just before the final whistle. Int. J. Environ. Res. Public Health 2020, 17, 5955 4 of 11

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Humidity71%64% Barometer1021 mbar Visibility20 km Time14:0013:0012:00 Temp131210Conditions °C PartlyWeather sunny 97Wind km/hComfort Humidity58%64%71% Barometer1021 mbar Visibility20 km Time14:0013:0012:00 Temp131210Conditions °C PartlyWeather sunny 97Wind km/hComfort Humidity58%64%71% Barometer1021 mbar Visibility20 km 14:00Time12:0014:0013:00 Temp101312Conditions °C13 Partly◦CWeather sunny Partly sunny79Wind km/hComfort Humidity 9 km71%58%64% /h Barometer1021 58% mbar Visibility 102120 km mbar 20 km Time13:0014:00 Temp1213Conditions °C PartlyWeather sunny 9Wind km/hComfort Humidity64%58% Barometer1021 mbar Visibility20 km Time15:0014:0012:0013:00 Temp131012 °C PartlyOvercastWeather sunny 97Wind km/h Humidity58%59%71%64% Barometer1021 mbar Visibility20 km 15:0012:0014:0013:00 Temp131012 °C PartlyOvercastWeather sunny 97Wind km/h Humidity59%71%58%64% 1021 mbar 20 km 15:0012:0015:0013:0014:00 Temp101312 °C13 PartlyCOvercastWeather sunny Overcast 79Wind km/h Humidity 9 km71%59%64%58%/h 1021 59% mbar 102120 km mbar 20 km 14:0012:0015:0013:00 131012 °C Partly◦ Overcast sunny 97 km/h 58%71%59%64% 1021 mbar 20 km 12:0016:0015:0013:0014:00 101312 °C°C PartlyOvercast sunnysunny 79 km/h 71%59%64%58% 1021 mbar 20 km 16:0012:0013:0015:0014:00 131012 °C PartlyOvercast sunny 79 km/h 59%71%64%58% 1021 mbar 20 km 13:0016:0014:0015:00 1213 °C PartlyOvercast sunny 97 km/h 64%59%58% 1021 mbar 20 km 16:0015:0013:0016:0014:00 1312 °C13 Partly◦COvercast sunny Overcast 97 km/h 7 km59%64%58%/h 1021 59% mbar 102120 km mbar 20 km 13:0017:0016:0014:0015:00 1213 °C°C PartlyOvercast sunny 97 km/h 64%67%59%58% 10211022 mbar 20 km 17:0013:0015:0014:0016:00 1213 °C PartlyOvercast sunny 79 km/h 67%64%59%58% 10221021 mbar 20 km 14:0017:0016:00 1312 °C PartlyOvercast sunny 97 km/h 58%67%59% 10211022 mbar 20 km 17:0016:0014:0017:0015:00 1312 °C°C12 PartlyCOvercast sunny Overcast 79 km/h 7 km59%58%67%/h 10211022 67% mbar 102220 km mbar 20 km 14:0018:0015:0017:0016:00 131112 °C Partly◦ Overcast sunny 1197 km/h km/h 58%74%59%67% 10211022 mbar 2016 km 14:0016:0015:0018:0017:00 131112 °C PartlyOvercast sunny 1197 km/h km/h 58%59%74%67% 10211022 mbar 2016 km 17:0015:0018:00 121311 °C PartlyOvercast sunny 1179 km/h km/h 67%59%74% 10221021 mbar 2016 km 15:0019:0018:0016:0017:00 13101112 °C°C PartlyOvercast sunny 1197 km/h km/h 59%80%74%67% 102110231022 mbar 201116 km 18:0015:0019:0016:0018:0017:00 13101112 °C11 Partly◦COvercast sunny Partly sunny1197 km/h km/h 11 km59%80%74%67%/h 102110231022 74% mbar 1022201116 km mbar 16 km 17:0016:0019:0018:00 12131011 °C PartlyOvercast sunny 1179 km/h km/h 67%59%80%74% 102210211023 mbar 201116 km 18:0016:0019:00 111310 °C PartlyOvercast sunny 1179 km/hkm/h 74%59%80% 102210211023 mbar 162011 km 16:0020:0019:0017:0018:00 131012119 °C °C°C PartlyOvercastFog sunny 1179 km/h km/h 59%85%80%67%74% 1021102410231022 mbar 2011168 km km 19:0016:0020:0017:0019:0018:00 131210119 °C°C10 PartlyCOvercastFog sunny Partly sunny1179 km/h km/h 9 km59%85%67%80%74%/h 1021102410221023 80% mbar 10232011168 kmkm mbar 11 km 17:0020:0018:0019:00 1211109 °C °C Partly◦ OvercastFog sunny 1179 km/h km/h 67%85%74%80% 102210241023 mbar 2016118 km km 19:0017:0020:0018:00 1012119 °C °C PartlyOvercastFog sunny 1197 km/h km/h 80%67%85%74% 102310221024 mbar 1120168 km km 17:0021:0020:0018:0019:00 12111089 °C °C°C PartlyOvercastFog sunny 11769 km/h km/h 67%85%86%74%80% 1022102410251023 mbar 201016118 km km 21:0017:0019:0018:0020:00 12101189 °C °C PartlyOvercastFog sunny 11679 km/h km/h 86%67%80%74%85% 1025102210231024 mbar 102011168 kmkm 20:0018:0021:0020:00 1189 °C°C 9 ◦PartlyCOvercastFog sunny Fog 1167 km/hkm/h 7 km74%86%85%/h 102210251024 85% mbar 102416108 kmkm mbar 8 km 20:0018:0021:0019:00 111098 °C °C°C PartlyOvercastFog sunny 11769 km/hkm/h 85%74%86%80% 1024102210251023 mbar 1610118 km km 18:0022:0019:0021:0020:00 1110789 °C°C PartlyOvercastFog sunny 112967 km/hkm/h 74%90%80%86%85% 1022102510231024 mbar 16111078 kmkm 20:0019:0022:0021:00 10978 °C °C PartlyOvercastFog sunny 7926 km/h 85%80%90%86% 102410231025 mbar 111087 km km 21:0021:0019:0022:00 1087 °C °C 8 PartlyCOvercastFog sunny Overcast 692 km/h 6 km86%80%90%/h 10251023 86% mbar 102510117 kmkm mbar 10 km 19:0023:0022:0020:0021:00 106798 °C°C ◦PartlyOvercastFog sunny 94276 km/h 80%93%90%85%86% 102310251024 mbar 1110478 km km 19:0023:0020:0022:0021:00 106978 °C°C PartlyOvercastFog sunny 94726 km/h 80%93%85%90%86% 102310251024 mbar 1110487 kmkm 20:0023:0021:0022:00 9687 °C OvercastFog 7462 km/h 85%93%86%90% 10241025 mbar 10847 km km 22:0020:0023:0021:00 7968 °C OvercastFog 2746 km/h 90%85%93%86% 10251024 mbar 10784 km km 22:0020:0000:0023:0021:0022:00 94687 °C°C 7 ◦COvercastFog Fog7246 km/h 2 km85%93%86%90%/h 102410261025 90% mbar 1025108247 km km mbar 7 km 00:0020:0022:0021:0023:00 49786 °C OvercastFog 2764 km/h 93%85%90%86% 102610241025 mbar 102874 km km 21:0000:0023:00 846 °C OvercastFog 624 km/h 86%93% 10251026 mbar 1024 kmkm 23:0021:0000:0022:00 6847 °C°C OvercastFog 462 km/h 93%86%90% 10251026 mbar 10427 km km 23:0021:0001:0022:0000:0023:00 82746 °C 6 COvercastFog Fog624 km/h 4 km86%96%90%93%/h 10251026 93% mbar 1025101724 kmkm mbar 4 km 21:0023:0022:0001:0000:00 86724 °C ◦ OvercastFog 642 km/h 86%93%90%96% 10251026 mbar 104712 kmkm 00:0022:0001:00 472 °C Fog 2 km/h 93%90%96% 10261025 mbar 271 km 22:0002:0001:0023:0000:00 7264 °C°C Fog No24 km/h wind 90%97%96%93% 10251026 mbar 70142 km 22:0002:0023:0001:0000:00 7264 °C Fog No24 km/h wind 90%97%93%96% 10251026 mbar 70412 km 00:0023:0002:0000:0001:00 624 °C 4 ◦CFog FogNo42 km/h wind 2 km93%97%96%/h 10251026 93% mbar 10264021 km mbar 2 km 01:0023:0002:0000:00 264 °C Fog No24 km/h wind 96%93%97% 10261025 mbar 1402 km 23:0003:0002:0000:0001:00 6204 °C°C Fog No42 km/h wind 93%97%98%96% 10251026 mbar 4021 km 03:0023:0001:0000:0002:00 0624 °C Fog No42 km/h wind 98%93%96%97% 10261025 mbar 0412 km 01:0000:0003:0002:00 402 °C 2 CFog FogNo2 km/h wind 2 km93%98%97%/h 1026 96% mbar 102620 km mbar 1 km 02:0000:0003:0001:00 240 °C°C ◦ Fog No2 km/h wind 97%93%98%96% 1026 mbar 021 km 00:0004:0001:0003:0002:00 420 °C Fog No2 km/h wind 93%99%96%98%97% 1026 mbar 201 km 02:0001:0004:0003:00 20 °C Fog No2 km/h wind 97%96%98%99% 1026 mbar 01 km 03:0001:0004:00 02 °C Fog No2 km/h wind 98%96%99% 1026 mbar 01 km 02:0001:0005:0004:0002:0003:00 230 °C°C 2 ◦CFog FogNo2 km/h wind No96%99%97%98% wind 1026 97% mbar 102610 km mbar 0 km 01:0005:0002:0004:0003:00 230 °C Fog No2 km/h wind 96%99%97%98% 1026 mbar 10 km 02:0005:0003:0004:00 230 °C Fog No2 km/h wind 97%98%99% 1026 mbar 0 km 04:0002:0005:0003:00 230 °C Fog No2 km/h wind 99%97%98% 1026 mbar 0 km 03:0002:0006:0005:0003:0004:00 230 °C°C 0 CFog FogNo2 km/h wind No97%99%98% wind 10261027 98% mbar 102601 km mbar 0 km 06:0002:0004:0003:0005:00 320 °C ◦ Fog No2 km/h wind 99%97%98% 10271026 mbar 10 km 03:0006:0005:00 03 °C Fog No2 km/h wind 98%99% 10261027 mbar 01 km 05:0003:0006:0004:00 302 °C°C Fog No2 km/h wind 98%99% 10261027 mbar 01 km 03:0007:0004:0006:0005:00 0423 °C Fog No2 N/Akm/h wind 100%98%99% 10261027 mbar 01 km 04:0005:0004:0007:0006:00 324 °C 2 ◦CFog FogNo2 N/Akm/h wind 2 km100%99%/h 10261027 99% mbar 102601 km mbar 0 km 04:0007:0006:00 243 °C Fog No2 N/Akm/h wind 100%99% 10261027 mbar 01 km 06:0004:0007:0005:00 324 °C°C Fog No2 N/Akm/h wind 100%99% 10271026 mbar 10 km 04:0008:0005:0007:0006:00 2534 °C Fog No2 N/Akm/h wind 100%99% 10261027 mbar 021 km 04:0006:0005:0008:0007:00 2354 °C Fog No2 N/Akm/h wind 100%99% 10261027 mbar 012 km 05:0007:0005:0008:00 435 °C 3 ◦CFog Fog2 N/Akm/h 2100% km99%/h 10271026 99% mbar 1026102 km mbar 0 km 05:0009:0008:0006:0007:00 3654 °C°C Fog No2 N/Akm/h wind 100%99% 10261027 mbar 0321 km 05:0009:0006:0008:0007:00 3654 °C Fog No2 N/Akm/h wind 100%99% 10261027 mbar 0312 km 06:0009:0007:0008:00 3645 °C Fog NoN/A wind 100%99% 1027 mbar 132 km 06:0008:0006:0009:0007:00 5364 °C 3 ◦CFog FogNoN/A wind No100%99% wind 1027 99% mbar 1027213 km mbar 1 km 06:0010:0009:0007:0008:00 38645 °C°C Fog No2 N/Akm/h wind 100%99%96% 10271028 mbar 1382 km 10:0006:0008:0007:0009:00 83546 °C Fog No2 N/Akm/h wind 100%96%99% 10281027 mbar 8123 km 07:0010:0009:00 486 °C Fog No2 N/Akm/h wind 100%96% 10271028 mbar 183 km 07:0009:0007:0010:0008:00 6485 °C 4 ◦CFog FogNo2 N/Akm/h wind N100%96%/A 10271028 100% mbar 10273182 km mbar 1 km 07:0011:0010:0008:0009:00 4856 °C°C OvercastFog No24 N/Akm/h wind 100%96%87% 10271028 mbar 111823 km km 11:0007:0009:0008:0010:00 8465 °C OvercastFog No42 N/Akm/h wind 100%87%96% 10281027 mbar 111328 kmkm 08:0011:0010:00 58 °C OvercastFog 42 N/Akm/h 100%87%96% 10271028 mbar 1128 km km 08:0010:0008:0011:0009:00 856 °C°C 5 COvercastFog FogNo24 N/A km/h wind N100%96%87%/A 10281027 100% mbar 102711823 km km mbar 2 km 08:0009:0011:0010:00 568 °C ◦ OvercastFog No42 N/Akm/h wind 100%87%96% 10271028 mbar 11238 km km 2.3.1. Study08:0010:0009:0011:00 Protocol—MRI 586 °C OvercastFog No24 N/Akm/h wind 100%96%87% 10271028 mbar 11238 km km 2.3.1. Study11:0009:00 Protocol—MRI 86 °C OvercastFog No4 km/h wind 100%87% 10281027 mbar 113 kmkm 2.3.1. Study09:0009:0010:0011:00 Protocol—MRI 68 °C°C 6 COvercastFog FogNo24 km/h wind No100%96%87% wind 10271028 100% mbar 10271138 km km mbar 3 km 2.3.1. Study09:0010:0011:00 Protocol—MRI 68 °C ◦ OvercastFog No24 km/h wind 100%96%87% 10271028 mbar 1138 km km 2.3.1.MRI Study was10:0011:00 Protocol—MRI performed 8 °Ctwice: OvercastoneFog day after24 thekm/h 24 ‐h UM96%87% run and1028 exactly mbar 3 years118 km km later, using a 2.3.1.MRI Study was10:0011:00 Protocol—MRI performed 8 °Ctwice: OvercastoneFog day after24 thekm/h 24 ‐h UM96%87% run and1028 exactly mbar 3 years118 km km later, using a Philips2.3.1.MRI Study Achieva10:00 was10:0011:00 Protocol—MRI performed 3T TX clinical8 °Ctwice: 8 Cscanner OvercastoneFog day (Philips after Fog24 thekm/h Medical 24 ‐h 2UM kmSystems,96%87%/ hrun and 1028Aurora, 96%exactly mbar OH, 3 1028years 118USA) km km mbar later, with usinga 8knee km a 2.3.1.PhilipsMRI Study Achieva was10:0011:00 Protocol—MRI performed 3T TX clinical8 °Ctwice: ◦ scanner OvercastoneFog day (Philips after24 thekm/h Medical 24 ‐h UM Systems,96%87% run and 1028Aurora, exactly mbar OH, 3 years 118USA) km km later, with usinga knee a Philips2.3.1.MRI Study Achieva was11:00 Protocol—MRI performed 3T TX clinical8 °Ctwice: scanner Overcastone day (Philips after4 thekm/h Medical 24 ‐h UM Systems,87% run and 1028Aurora, exactly mbar OH, 3 years 11USA) km later, with usinga knee a extremity2.3.1.PhilipsMRI Study Achieva wascoil.11:00 Protocol—MRI performed The3T TX patient clinical8 °Ctwice: underwent scanner Overcastone day (Philips afterimaging4 thekm/h Medical 24according ‐h UM Systems,87% run to and 1028theAurora, exactly standardmbar OH, 3 years 11USA)knee km later, withprotocol usinga knee of a PhilipsextremityMRI Achieva wascoil.11:00 performed The3T TX patient clinical8 °Ctwice: underwent scanner Overcastone day (Philips afterimaging4 thekm/h Medical 24according ‐h UM Systems,87% run to and 1028theAurora, exactly standardmbar OH, 3 years 11USA)knee km later, withprotocol using a knee ofa twoextremityPhilips2.3.1.‐dimensionalMRI Study Achieva11:00 wascoil.11:00 Protocol—MRI performed The3T (2D) TX patient thin clinical8 °Ctwice: slices 8underwent◦ Cscanner Overcastonein sagittal day (Philips Overcast afterimaging (PDW/PDW4 thekm/h Medical 24according ‐h 4 UM SPAIR), kmSystems,87%/ hrun to andcoronal 1028theAurora, 87% exactly standardmbar (PDW OH, 3 1028 years 11SPAIR/PDWUSA)knee km mbar later, withprotocol usinga 11 TSE),knee kmof a twoextremity2.3.1.Philips‐dimensionalMRI Study Achieva wascoil. Protocol—MRI performed The 3T(2D) TXpatient thin clinical twice: slices underwent scanner onein sagittal day (Philips afterimaging (PDW/PDW the Medical 24according‐h UM SPAIR),Systems, run to andcoronal theAurora, exactlystandard (PDW OH, 3 years SPAIR/PDWUSA)knee later, withprotocol usinga TSE),knee of a Philips2.3.1.twoextremity‐dimensionalMRI Study Achieva wascoil. Protocol—MRI performed The3T (2D) TX patient thin clinical twice: slices underwent scanner onein sagittal day (Philips afterimaging (PDW/PDW the Medical 24according‐h UM SPAIR),Systems, run to andcoronal theAurora, exactlystandard (PDW OH, 3 years SPAIR/PDWUSA)knee later, withprotocol usinga TSE),knee ofa 2.3.1.paracoronaltwoPhilipsextremity‐dimensionalMRI Study Achieva wascoil. 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Protocol—MRI([ACL]: performed The (2D) images T2Wpatient thin TSE)twice: slices(3D) underwent and onefastin axial sagittal dayspin (T1/T2FS/PDW afterimaging‐echo (PDW/PDW the sequences 24according‐h SPAIR)UM SPAIR), (sagittal:run to planes. andcoronalthe exactlyPD standardMRI (PDWSPAIR acquisition 3 years SPAIR/PDWknee HR/HI later, protocolof‐ 3D)isotropic using TSE),was ofa paracoronalthreePhilipsextremitytwo‐dimensionalMRI‐dimensional Achieva wascoil. ([ACL]: performed The3T (2D) images TX T2Wpatient thin clinical TSE)twice: slices(3D) underwent andscanner one fastin axial sagittal dayspin (Philips(T1/T2FS/PDW afterimaging‐echo (PDW/PDW the Medicalsequences 24according‐h SPAIR)UM SPAIR),Systems, (sagittal:run to planes. andcoronal theAurora, exactlyPD standardMRI (PDWSPAIR OH, acquisition 3 years SPAIR/PDWUSA)knee HR/HI later, with protocolof‐ 3D)isotropic using a TSE),kneewas ofa twothreePhilipsextremityparacoronaltwo‐‐dimensionalMRI‐dimensional Achieva wascoil. ([ACL]: performed The 3T (2D)(2D) images TX T2Wpatient thinthin clinical TSE)twice: slicesslices(3D) underwent andscanner one infastin axial sagittalsagittal dayspin (Philips(T1/T2FS/PDW afterimaging‐ echo (PDW/PDW(PDW/PDW the Medicalsequences 24according‐h SPAIR)UM SPAIR),Systems, (sagittal:run to planes. andcoronal theAurora, exactlyPD standardMRI (PDW(PDW SPAIROH, acquisition 3 years SPAIR/PDWUSA)knee HR/HI later, with protocolof‐ 3D)isotropic using a TSE), kneewas ofa Philipsperformedthreetwoextremityparacoronal‐dimensionalMRI‐dimensional Achieva was coil.as ([ACL]: well. performed The3T (2D) The images TX T2Wpatient thin menisci,clinical TSE)twice: slices(3D) underwent and scannerligaments, onefastin axial sagittal dayspin (Philips (T1/T2FS/PDW after imaging‐andecho (PDW/PDW cartilagethe Medicalsequences 24according‐h wereSPAIR)UM SPAIR),Systems, (sagittal:run assessed to planes. andcoronal theAurora, exactly usingPD standardMRI (PDW SPAIROH, theacquisition 3 years standardSPAIR/PDWUSA)knee HR/HI later, with protocolof sequence.‐ 3D)isotropic usinga TSE),kneewas ofa paracoronalPhilipsthreetwoextremityperformed‐dimensional‐dimensional Achieva coil.as ([ACL]: well. 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PDusing MRI SPAIR acquisitionthe standard HR/HI of ‐sequence. 3D)isotropic was threeperformed‐dimensional as well. Theimages menisci, (3D) ligaments, fast spin ‐andecho cartilage sequences were (sagittal: assessed PDusing SPAIR the standard HR/HI ‐sequence.3D) was performedthree‐dimensional as well. Theimages menisci, (3D) ligaments, fast spin ‐andecho cartilage sequences were (sagittal: assessed usingPD SPAIR the standard HR/HI sequence.‐3D) was performed as well. The menisci, ligaments, and cartilage were assessed using the standard sequence. performed as well. The menisci, ligaments, and cartilage were assessed using the standard sequence. Int. J. Environ. Res. Public Health 2020, 17, 5955 5 of 11

2.3.1. Study Protocol—MRI MRI was performed twice: one day after the 24-h UM run and exactly 3 years later, using a Philips Achieva 3T TX clinical scanner (Philips Medical Systems, Aurora, OH, USA) with a knee extremity coil. The patient underwent imaging according to the standard knee protocol of two-dimensional (2D) thin slices in sagittal (PDW/PDW SPAIR), coronal (PDW SPAIR/PDW TSE), paracoronal ([ACL]: T2W TSE) and axial (T1/T2FS/PDW SPAIR) planes. MRI acquisition of isotropic three-dimensional images (3D) fast spin-echo sequences (sagittal: PD SPAIR HR/HI-3D) was performed as well. The menisci, ligaments, and cartilage were assessed using the standard sequence.

2.3.2. Ethical Approval This case report was approved by the ethical review board of the Bioethics Committee of the Healthy Life Style Foundation in Pułtusk (EC 3/2017/medicine/sports, approval date: 30 March 2017). All runners provided their written informed consent to participate in the analysis and for their data to be published.

3. Results

3.1. Data Related to 24-h UM Run During the 24-h UM, the athlete ran 258.228 km. He began the UM without any symptoms (no pain). The athlete started to experience right knee pain after approximately 12 h of running (approximately 130 km), which intensified until the end of the race. He ran on a 1984 m rectangular loop (950 42 m). The winner completed 516 rectangular corners, running in an atypical clockwise × fashion. The women’s world record in the 24H UM was set in the same race with a result of 256.245 km.

3.2. MRI Was Performed Twice: 1 Day after the 24-h UM Run and Exactly 3 Years Later

(a) Right knee MRI: One day after 24-h UM run

MRI examination revealed considerable joint effusion with synovial edema. Linear tear of the anterior root of lateral meniscus was diagnosed, whereas the medial meniscus was intact. Both crucial ligaments were intact. There were overload and post-traumatic lesions tangential to the distal biceps femoris short head and around the plate of the myotendinous junction. We also observed an edema of distal muscle fibers of biceps femoris and a small hemolyzed hematoma of this area penetrating tangentially to the posterior medial edge of the fibula head. There were features of lateral collateral ligament (LCL) overload changes expressed by distal ligament edema and periarticular soft-tissue edema. On the other hand, the medial collateral ligament (MCL) was intact. The quadriceps and patellar tendons were normal. The width of the articular cartilage of the tibiofemoral and patellofemoral joints were normal with a homogenous signal, no signs of chondromalacia, and usual subchondral bone marrow signal. The joint space was identified as normal. There was a trace of fluid in the semimembranosus-gastrocnemius bursa and an edema in the Hoffa’s fat pad.

(b) Right knee MRI: three years later

There was a large effusion with synovial edema in the joint cavity. We observed a progression of lateral meniscal tear. We detected a horizontal, stable tear of the lateral meniscal body, without dislocation. The medial meniscus was intact. We observed no changes in either crucial or collateral ligaments. The quadriceps and patellar tendons were normal. The appearance of articular cartilage of tibiofemoral and patellofemoral joints showed no abnormalities. We observed a normal subchondral bone marrow signal. There was no overload periarticular edema of soft tissue. We detected traces of fluid in the semimembranosus-gastrocnemius bursa and the edema Hoffa’s fat pad. Int. J. Environ. Res. Public Health 2020, 17, 5955 6 of 11

3.3. Interview Regarding Pain, Preferred Running Direction, Shape, and Loop Length for 24-h UM Run We gathered information on post-race pain, preferred loop shapes, and preferred running direction from 10 UM runners from the top 20 of the 24-h UM run. The predominant ailment was right knee pain (50%), followed by right hip pain (20%), and left calf pain (20%). Their preferences were treadmill shape: athletic stadium-shape (70%), loop length: 2000 or 2500 m (90%), and running direction: counterclockwise (100%). Detailed results are presented in Table2. Int. J. Environ. Res. Public Health 2020, 17, 5955 7 of 11

Table 2. Interview data from 10 competitors from the top 20 24-h UM runners regarding pain, preferred loop shapes, and running direction.

Distance Run Preferred Preferred Direction Preferred Direction Nr. during 24-h UM Sex Right Leg Pain Left Leg Pain Preferred Loop Shape Loop of Running—If of Running—If > 200 km Length Possible to Choose Only One Way 1 yes m Knee no athletic stadium-shape 2000 m Alternately Counterclockwise 2 yes f Knee no athletic stadium-shape 2000 m Alternately Counterclockwise 3 yes m no no athletic stadium-shape 2500 m Alternately Counterclockwise 4 yes f Knee and hip Achilles pain athletic stadium-shape 2500 m Alternately Counterclockwise 5 yes m no no -shape 2000 m Alternately ∞ 6 no m no ankle joint, calf strain athletic stadium-shape 2500 m Alternately Counterclockwise 7 no f Iliotibial band issue no athletic stadium-shape 2000 m Alternately Counterclockwise 8 no m Knee and Calf strain no -shape 2000 m Alternately Counterclockwise ∞ 9 no f no no -shape 2500 m Alternately Counterclockwise ∞ 10 no m Knee and hip Calf strain athletic stadium-shape 1000 m Alternately Counterclockwise f—female; m—male. -shape—Competitors run around a loop shaped like (infinity sign). Continuing to run in one direction, they make one turn clockwise and the other in the opposite direction (counter-clokwise).∞ In this way, they load the musculoskeletal∞ system symmetrically. Int. J. Environ. Res. Public Health 2020, 17, 5955 8 of 11

4. Discussion

4.1. Discussion of the Results The right knee pain reported by the athlete after the run was cause for MRI examination. MRI results, in addition to degenerative changes, showed asymmetrical changes associated with overload of the lateral compartment of the right knee joint. The runner completed 516 rectangular corners. During the run, his right knee was exposed to centrifugal force. This force affected the lateral knee compartment, leading to pain after the run. Posterolateral knee stabilization is provided by the arcuate ligament complex, comprising of the lateral collateral ligament, the biceps femoris tendon, the popliteus muscle and tendon, the popliteal meniscal and popliteal fibular ligaments, the oblique popliteal, the arcuate and fabellofibular ligaments, and the lateral gastrocnemius muscle [6]. The most important active stabilizer of the lateral side of this joint is the biceps femoris, and its distal attachment to the fibula head. Passive stabilization is provided by the lateral collateral ligament [7]. Both structures appeared overloaded in MRI images. MRI imaging revealed edema and overload changes in the attachment distal biceps femoris tendon to the fibula head, a small hemolyzed hematoma penetrating tangentially to the posterior medial edge of the fibula head, features of LCL overload, distal ligament edema, linear tear of the anterior root of the lateral meniscus, and periarticular soft-tissue edema (Figure3A,B). It is highly likely that the lateral knee compartment overload caused by completion of over five hundred rectangular corners could be the reason for the described MRI observations. Most changes (except for

Int.the J. lateral Environ. meniscus Res. Public Health tear, which2020, 17, cannot x heal) were not observed after three years. 7 of 10

Figure 3. ((A)) Magnetic Resonance Imaging 2017 (axial scan), overload and post-traumaticpost‐traumatic lesions tangential to the distal biceps femoris short head and around the plate of the myotendinous junction (arrow 1), an edema, a smallsmall hemolyzed hematoma penetrating tangentially to the posterior medial edge of the fibulafibula head and periarticular soft-tissuesoft‐tissue edema (arrow 2). ( (BB)) Re Re-examination‐examination in in 2020. 2020. Overload effects effects from post-runpost‐run examination areare absent.absent.

The interviewinterview collectedcollected data data from from 10 10 out out of of 20 20 leading leading competitors competitors to determine to determine pain pain classes classes after afterthe run the and run their and preferences their preferences for this typefor this of competition. type of competition. Half of them, Half including of them, two including world-class two worldrunners,‐class reported runners, pain reported in their pain right in knee. their Accordingright knee. toAccording UM runners, to UM the runners, ideal loop the shape ideal forloop a shape24-h UM for runa 24‐ shouldh UM run resemble should a resemble typical 400 a typical m stadium 400 m track stadium and track have and a length have a of length 2000 orof 25002000 m.or 2500The race m. The should race take should place take in alternating place in alternating directions. directions. In situations In situations of technical of impossibility, technical impossibility, the widely thepreferred widely direction preferred is direction counterclockwise. is counterclockwise. The athlete’s The knee athlete’s pain knee can be pain explained can be explained by the overload by the overloadassociated associated with the unfortunate with the unfortunate rectangular rectangular shape of the shape loop of (four the right loop angles(four right on each angles loop) on and each in loop)addition, and the in oppositeaddition, directionthe opposite of the direction run was of a problemthe run was for thea problem athlete, whofor the had athlete, adapted who to “lefthad adaptedturns” after to “left years turns” of training. after Theyears reasons of training. for a preferredThe reasons “counterclockwise” for a preferred direction,“counterclockwise” otherwise direction, otherwise generally recognized as “natural”, are a matter of speculation (“heart on the left, right leg stronger and longer, etc.”) rather than scientific evidence (see discussion below).

4.2. Knee Overload Injuries in UM Runners In longer ultramarathons, approximately 50–60% of participants experience musculoskeletal problems. Most common injuries in ultramarathoners involve the lower limb, e.g., the ankle or the knee [8–10]. The knee is the most common region of exercise‐related injury [11], accounting for 20% of all injuries among 161 km ultramarathon runners [12]. Some MRI studies show that even running 4487 km in a multistage UM does not cause permanent negative changes in the knee joint [13,14]. Potential overload injuries during long runs are influenced by a number of individual factors: biochemical, clinical, and anthropometric [15]. There are a few well‐documented studies that testify knee joint adaptability, even on extreme mountain UMs [16]. A prospective MRI study of one knee from ten randomly selected participants who completed the Comrades Marathon between 1997 and 2002 was performed by Hagemann et al. UM runners’ knees were scanned 48 h before the race, and 48 h and one month after the 89 km oldest UM race. The race appears to have had a detrimental effect on runners who started the ultramarathon with tendinopathy, which worsened post‐race by MRI criteria. One month after the race, the scan appearance of the injury had either improved or resolved completely [17]. None of these studies, however, looked at the tendency of just one knee (e.g., right) to undergo more frequent stress injuries. To our knowledge, there are no previous studies on 24‐h runs in a single direction and related asymmetrical knee overload. Int. J. Environ. Res. Public Health 2020, 17, 5955 9 of 11 generally recognized as “natural”, are a matter of speculation (“heart on the left, right leg stronger and longer, etc.”) rather than scientific evidence (see discussion below).

4.2. Knee Overload Injuries in UM Runners In longer ultramarathons, approximately 50–60% of participants experience musculoskeletal problems. Most common injuries in ultramarathoners involve the lower limb, e.g., the ankle or the knee [8–10]. The knee is the most common region of exercise-related injury [11], accounting for 20% of all injuries among 161 km ultramarathon runners [12]. Some MRI studies show that even running 4487 km in a multistage UM does not cause permanent negative changes in the knee joint [13,14]. Potential overload injuries during long runs are influenced by a number of individual factors: biochemical, clinical, and anthropometric [15]. There are a few well-documented studies that testify knee joint adaptability, even on extreme mountain UMs [16]. A prospective MRI study of one knee from ten randomly selected participants who completed the Comrades Marathon between 1997 and 2002 was performed by Hagemann et al. UM runners’ knees were scanned 48 h before the race, and 48 h and one month after the 89 km oldest UM race. The race appears to have had a detrimental effect on runners who started the ultramarathon with tendinopathy, which worsened post-race by MRI criteria. One month after the race, the scan appearance of the injury had either improved or resolved completely [17]. None of these studies, however, looked at the tendency of just one knee (e.g., right) to undergo more frequent stress injuries. To our knowledge, there are no previous studies on 24-h runs in a single direction and related asymmetrical knee overload.

4.3. Why Do Athletes Run Around the Track Counterclockwise?—A Lot of Gossip and Poor Scientific Evidence Although obvious for many, it is not scientifically proven. There are many popular scientific theories on this subject. According to Tavakkoli and Jose:

“In 1896, the First Modern was held in Athens, Greece. During this event the athletes were required to run clockwise during the track events. This was met with much complaint from the athletes. It was because of these complaints that the IOC then gathered in 1913 and set the current anticlockwise rule. We run counterclockwise because everything in nature tends towards counterclockwise motion. An spectator will perceive the runners as moving left to right, the same direction our eyes move when we read. The human body is slightly heavier on the left than the right because of the heart and when running anticlockwise, the body would tend to very slightly incline towards the left, which could be an advantage while running anticlockwise. Because most people are right hand/leg dominant, moving counterclockwise we have a better control and move faster.” [18]

Ultimately, studies by Bestaven and others could not confirm any of these theories. He studied many aspects responsible for the tendency to turn. For instance, with closed eyes people turned left (50% of respondents), right (39%), or kept on moving straight (11%). These studies confirmed that veering is not due to mechanical asymmetries but could be related to an asymmetry in sensorial inputs [19]. Regardless, just because 50% of people with eyes closed turn left does not mean running left is healthier than running right. Most sports, and in fact most other things involving some sort of circular movement, do go counterclockwise. Think about athletics track races, track bicycle races, speed skating, , the customary flow of people around an ice-skating rink, the direction of dancers moving around a dance floor, motorcycle speedway, NASCAR , , [20]. Other reasons (“better to the left direction”) are more suggestions, and are not necessarily scientific or proven facts [20]. The guidelines from the International Association of Athletics Federations (IAAF) on this topic agree with the counterclockwise preference of the athletes in our study and state: “The direction of running shall be left-hand inside” (IAAF Rule 163.1) [21]. Int. J. Environ. Res. Public Health 2020, 17, 5955 10 of 11

4.4. Limitation An important limitation is the fact that MRI examination of one knee was performed right after the run. We do not have a pre-run test or second knee for comparison; neither do we have other athletes in the sample. Unfortunately, the individual biomechanical conditions of the runner were not taken into account in the assessment of knee loads. Follow-up examination after three years is a distant examination. An explanation is the fact that the planned extensive initial and control tests of the athlete had a cardiological profile [22]. Orthopedic complaints reported at the finish line by the examined athlete and other participants became the reason for performing the knee examination and subsequent interviews. Right knee MRI follow-up was accompanied by extensive cardiological re-diagnosis and performed as a preliminary pre-competition test (which did not take place due to the COVID-19 pandemic).

4.5. Perspectives To properly document the harmful effects of running in one direction in a 24-h UM run, MRI tests of both knee joints on many competitors should be performed both before and after the run. Ideally, the study should be conducted in three different 24-h UMs conducted in clockwise, counterclockwise, and alternating directions. Such results could then provide a strong argument for the competition organizers of 24-h UM to consider loop characteristics and competition methodology.

5. Conclusions Our results suggest that a one-way, clockwise, 24-h UM run had an adverse effect on the athlete’s right knee as a result of unsymmetrical load which distorted the final result. Organizers of 24-h UMs, responsible for the competitors’ health, objectivity, and results quality, should also take into account the shape of the loop and apply the principle of uniform load on the musculoskeletal system performing 24-h UM in alternate directions. In a situation of technical impossibility, it would be better to run in a counterclockwise direction, which is more common, preferred by runners, and recommended by the IAAF.

Author Contributions: R.G. conceived of and designed the study. P.W. and M.J. analyzed and interpreted the MRI examinations. R.G. collected the data. R.G., P.W., and M.J. revised the manuscript and approved the final version. All authors have read and agreed to the published version of the manuscript. Funding: This research received no external funding. Acknowledgments: The authors thank Andrzej Radzikowski and other UM runners who consented to the use of their medical data in this study. Conflicts of Interest: The authors declare no conflict of interest.

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