Gasser B 1 OriGINAliA ACCEPTED: DatumFebruary 2017 PUBLISHED ONLINE: MarchDatum 2017 Night Versus Day Orienteering – DOI:10.5960/dzsm.2017.274Nummer Gasser B. Night Versus Day Orienteering – an Analysis of Differences in Speed. Dtsch Z an Analysis of Differences in Speed Sportmed. 2017, 68: 67-72. Nacht versus Tag Orientierungslauf – Eine Analyse hinsichtlich unterschiedlicher Laufgeschwindigkeiten Summary Zusammenfassung 1. UNIVERSITY OF BERN, Swiss Health & Performance Lab, Institute of › Introduction: It is to be expected that orienteering at night is › Einleitung: Orientierungslaufen in der Nacht ist durch spezifi- Anatomy, Bern, Switzerland more difficult due to light restriction for map-reading. This study sche Charakteristika gekennzeichnet, wobei insbesondere an die aims to analyze the differences in speed at night versus daytime. kartentechnischen Fähigkeiten vermutlich höhere Anforderun- › Methods: The last three night Swiss Orienteering Champion- gen gestellt werden, was sodann zur adressierten Fragestellung ships were analyzed concerning average speed (performance per dieser Untersuchung abweichender Laufgeschwindigkeiten an km as divisor of course time and the sum of horizontal distance Tag versus Nacht führt. in km and differences in altitude per 100m) and compared with › Methodik: Die letzten drei Nacht-OL Schweizer Meisterschaf- day courses. ten wurden mit Hilfe des im Trailrunning und O-Bereich häufig › Results: In night as well as in day competitions a U-shaped age/ verwendeten Leistungskilometerkonzeptes (durchschnittlicher speed relation could be detected in men with a minimum at 24.9 Leistungskilometer als Teiler der Laufzeit und des zusammenfas- years respectively 6.2min in day versus 26.9 years respectively senden Leistungsaequivalents von 100 Höhenmetern und 1km 5.4min in night (Night R2=0.3564 / day R2=0.1437). The same Horizontaldistanz) bezüglich unterschiedlicher Geschwindig- pattern can be detected in women with 17.9 years respectively keitsmuster mit Orientierungsläufen am Tag verglichen. 8.3min in day versus 23.2 years respectively 7.3min in night com- › Resultate: Sowohl in der Nacht als auch am Tag zeigte sich bei petitions. (Night R2=0.0533/day R2=0.1909). den Herren eine U-förmige Alter/Laufgeschwindigkeitsbezie- › Discussion: Theresults are probably a consequence of a positive hung mit einem Minimum der durchschnittlichen Leistungs- selection bias that only well-trained competitors start in night kilometerzeit bei 24,9 Jahren respektive 6,2min am Tag versus orienteering, which is in principle in accordance with higher 26,9 Jahren respektive 5,4min in der Nacht (Nacht R2=0,3564/ map reading skills in night versus day courses. Furthermore, this Tag R2=0,1437). Dasselbe Muster setzt sich bei den Damen fort pattern can be detected when analyzing competitive categories mit 17,9 Jahren respektive 8,3min am Tag versus 23,2 Jahren re- but less when analyzing runners from recreational categories spektive 7,3min in der Nacht (Nacht R2=0,0533/Tag R2=0,1909). and might correlate with the aspect of specific preparation for › Diskussion: Die Resultate sind vermutlich eine Konsequenz ei- national competitions. nes positiven Selektionsbias dahingehend, dass nur Athleten mit gutem Niveau und entsprechender Vorbereitung an Nacht-Ori- entierungsmeisterschaften teilnehmen, was bei dezidierter Be- trachtung auch mit höheren kartentechnischen Anforderungen in der Nacht vereinbar ist. Das identifizierte Muster setzt sich bei isolierter Betrachtung in den eher wettkampforientierten Kate- gorien fort, nicht aber in den breitensportorientierten Kategorien und könnte entsprechend mit dem Aspekt der spezifischen Vor- bereitung für Meisterschaftsläufe korrelieren. Article incorporates the Creative Commons Attribution – Non Commercial License. https://creativecommons.org/licenses/by-nc-sa/4.0/ SCHLÜSSELWÖRTER: KEY WORDS: Orienteering, Night-Orienteering, Orientierungslaufen, Nacht-OL, Speed per Performance Km, Speed Leistungskilometer, Laufgeschwindigkeiten QR-Code scannen Introduction und Artikel online lesen. Orienteering is getting more and more popular in the forest with course times longer than 1.5 h in CORRESPONDING ADDRESS: and has become from a little-known sport mainly elite categories), middle-distance (runs in the forest Benedikt Gasser, MD practiced in Scandinavian countries to a well-known with course times around 40 minutes), sprint (runs Swiss Health & Performance Lab and wide-spread activity in Middle Europe, especi- in urban areas with course times about 20 minutes), Institute of Anatomy, University of Bern ally in Switzerland but also in Germany. The increa- night orienteering forms are becoming more and Baltzerstrasse 2, 3000 Bern, Switzerland : [email protected] singly leisure sports character has contributed to an more popular. One essential component in orientee- increase in different and new forms of competitions. ring sports is cognition with respect to map-techni- Thus, in addition to the original long-distance (runs cal capabilities, whereby it would appear that DEUTSCHE ZEITSCHRIFT FÜR SPORTMEDIZIN 68. Jahrgang 3/2017 67 OriGINAliA Nacht- versus Tag-Orientierungslauf Table 1 Subject data of the runners included from the years 2013, 2014 and 2015 (in each case Number=n/Age (Mean/Standard Deviation)). Categories: D18=junior women, H18=junior men, DAK=short-distance women, HAK= short-distance men, HE=male elite, DE=female elite, D45=senior women, H45=senior men. D18 H18 DAK HAK DE HE D45 H45 Night 2013 n=18 n=21 n=9 n=12 n=24 n=32 n=17 n=22 Age (Mean / SD) 20.5±0.5 17.4±0.5 29.6±7.3 43.1±7.8 24.9±4.6 26.1±4.7 46.5± 1.36 47.7±1.3 Day 2013 n=12 n=20 n=11 n=10 n=27 n=20 n=11 n=14 Age (Mean / SD) 20.4±0.5 20.5±0.5 31.5±9.1 45.1±12 32±8.3 29.3±4.3 50.4±1.6 50.5±1.4 Night 2014 n=20 n=21 n=12 n=14 n=20 n=34 n=15 n=21 Age (Mean / SD) 19.4±0.5 19.5±0.5 30.5±10.6 43.9±9.1 26.9±4.2 28.1±4.6 49.2±1.2 49.2±1.5 Day 2014 n=17 n=14 n=11 n=11 n=20 n=21 n=15 n=22 Age (Mean / SD) 19.5±0.5 19.5±0.5 31.3±9.6 40.5±10.1 27.6±5.4 30±7.8 48.9±1.3 49.1±1.5 Night 2015 n=19 n=24 n=11 n=13 n=24 n=33 n=17 n=24 Age (Mean / SD) 18.5±0.5 18.5±0.5 28±4.5 46.3±8.7 25.3±4.2 26.6±4.6 47±1.4 48±1.3 Day 2015 n=24 n=37 n=12 n=12 n=18 n=24 n=17 n=18 Age (Mean / SD) 18.4±0.5 18.4±0.5 34.8±12.2 41.6±9.9 29.4±17.8 26.1±4.3 48 ±1.5 48.2±1.3 the reduced light available at night is an impediment. Although still missing. This permits formulation of the central question new technically high-quality standard orienteering lamps are in this study as follows: is there a difference in mean running available for about the price of running shoes and have a high speeds at night compared to daytime? As hypothesis, in the light performance (2000 Lumen with a beam up to 300 meters), sense of possible, potential falsification, it is postulated that the the light conditions cannot be compared to daytime. This po- mean running times do not differ between runs in the daytime tentially brings more difficulty in orientation due to increased and at night (19). strain, especially on vision. Analyses have shown, for example, that visually-impaired orienteering runners (for example those Methods with green/red blindness) have substantial difficulty reading maps in the presentation forms defined by the IOF (Interna- Subjects tional Orienteering Federation). This is time-consuming and Orienteering runners in the categories junior women (D18) and hinders speed (17). Comparable effects can be assumed for junior men (H18), short-distance women (DAK) and men (HAK), map-reading in limited light at night (20). male elite (HE) and female elite (DE) and senior women (D45) If the general physiological demands of this type of sport are and senior men (H45), who participated in the Night-orientee- analyzed thoroughly, the doubtlessly important running capa- ring Swiss Orienteering Championships in the years 2013, 2014 city must also be emphasized. In principle, the cardiopulmonary and 2015. Table 1 shows the number and age of the 477 compe- system is a central and performance-determining element for titors in the night competitions versus 418 competitors in day the runner (7, 12, 13, 20). This system is responsible for guaran- competitions, arranged by year and category. teeing the blood supply to the skeletal muscles, especially in the lower extremities, during physical performance, for example in Procedure completing an orienteering course (13). The extent of blood sup- The average running speeds in the three night-orienteering ply, respectively oxygen, to the skeletal muscle decisively deter- Swiss Championships in the years 2013, 2014, 2015 were analy- mines the oxidative capacity of the organ and thus forms the zed in the categories cited above. To quantify the average run- biological limit of performance capacity (13). These processes ning speeds, the performance kilometer concept often used in are, in principle, the same day and night, apart from certain trail running and orienteering was applied. Set in relation to the environmental effects such as possibly lower temperature (4, 13). average performance kilometers separated by year and catego- In addition to the physical restrictions the cognitive com- ry, this was used as a correlate to running speed (1, 21). This was ponents in a second approximation must be mention. Thought applied according to the distance information provided by the processes are the same, in principle, day and night.