77:
246:, Keswick to Threlkeld), the equivalent flat distance of this route is 20+(1.6×8)=32.8 kilometres (20.4 mi). Assuming an individual can maintain a speed on the flat of 5 km/h, the route will take 6 hours and 34 minutes. The simplicity of this approach is that the time taken can be easily adjusted for an individual's own (chosen) speed on the flat; at 8 km/h (flat speed) the route will take 4 hours and 6 minutes. The rule has been tested on
31:
316:
187:
141:
The basic rule assumes hikers of reasonable fitness, on typical terrain, and under normal conditions. It does not account for delays, such as extended breaks for rest or sightseeing, or for navigational obstacles. For planning expeditions a team leader may use
Naismith's rule in putting together a
297:
Over the years several adjustments have been formulated in an attempt to make the rule more accurate by accounting for further variables such as load carried, roughness of terrain, descents and fitness (or lack of it). The accuracy of some corrections is disputed, in particular the speed at which
182:
Naismith's rule appears in UK statute law, although not by name. The
Adventure Activities Licensing Regulations apply to providers of various activities including trekking. Part of the definition of trekking is that it is over terrain on which it would take more than 30 minutes to reach a road or
207:
Alternatively, the rule can be used to determine the equivalent flat distance of a route. This is achieved by recognising that
Naismith's rule implies an equivalence between distance and climb in time terms: 3 miles (=15,840 feet) of distance is equivalent in time terms to 2000 feet of climb.
376:
Tranter's corrections make adjustments for fitness and fatigue. Fitness is determined by the time it takes to climb 1000 feet over a distance of ½ mile (800 m). Additional adjustments for uneven or unstable terrain or conditions can be estimated by dropping one or more fitness levels.
758:
In case of
Naismith rule and Langmuir corrections the same, not modified value of ascent and descent was used for the distance of 4 km as for 5 km – 600 m for the Naismith rule and 300 m for Langmuir corrections (not taking into account the equivalence between distance and
241:
That is, 7.92 units of distance are equivalent to 1 unit of climb. For convenience an 8 to 1 rule can be used. So, for example, if a route is 20 kilometres (12 mi) with 1600 metres of climb (as is the case on leg 1 of the
673:
For both distances he gives an additional 1 h per 2000 ft (600 m) of ascent. So Aitken doesn't take into account equivalence between distance and climb (proposed by Scarf in 1998).
1420:
1579:
1005:
670:
Aitken (1977) assumes that 1 h takes to cover 3 mi (5 km) on paths, tracks and roads, while this is reduced to 2½ mi (4 km) on all other surfaces.
289:
Sample calculations: p0 = 12 min / km (for 5 km / h speed), m = 0.6 km climb / 5 km distance = 0.12, p = 12 · (1 + 7.92 · 0.12) = 23.4 min / km.
1327:"Three presentations on geographical analysis and modeling: Non-isotropic geographic modeling speculations on the geometry of geography global spatial analysis"
253:
As you can see, the Scarf's assumption allows also to calculate the time for each speed, not just one as in case of the original
Naismith rule.
183:
refuge (by the quickest safe route), based on a walking speed of 5 kilometres per hour plus an additional minute for every 10 metres of ascent.
1326:
286:
This formula is true for m≥0 (uphill or flat terrain). It assumes equivalence of distance and climb by applying mentioned earlier α factor.
48:
expedition by calculating how long it will take to travel the intended route, including any extra time taken when walking uphill. This
930:
886:
692:
For a gentle decline (slopes between 5 degrees and 12 degrees) subtract 10 minutes for every 300 meters of descent
1385:
Scarf, Philip (20 Mar 2007). "Route choice in mountain navigation, Naismith's rule, and the equivalence of distance and climb".
662:
For example, if
Naismith's rule estimates a journey time of 9 hours and your fitness level is 25, you should allow 11.5 hours.
1270:
898:
1312:
Mountaincraft and
Leadership. Official Handbook of the Mountain Leader Training Boards of Great Britain and Northern Ireland
1361:
1085:
67:
Allow one hour for every 3 miles (5 km) forward, plus an additional hour for every 2,000 feet (600 m) of ascent.
337:
1584:
17:
1231:
1204:
1177:
1128:
862:
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1565:
Online
Naismith's rule hiking time calculator, plus adjustments for intended pace, trail conditions, and pack weight.
363:
345:
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194:
resulting from
Naismith's rule and Langmuir corrections for base speeds of 5 km/h and 4 km/h compared to
149:
It is possible to apply adjustments or "corrections" for more challenging terrain, although it cannot be used for
1054:
703:
of the slowest member of a party should be taken into account and thus a more practical formula for a group is:
341:
695:
For a steep decline (slopes greater than 12 degrees) add 10 minutes for every 300 meters of descent
211:
Professor Philip Scarf, Associate Dean of
Research and Innovation and Professor of Applied Statistics at the
1432:
1619:
726:
195:
114:
Today it is formulated in many ways. Naismith's 1 h / 3 mi + 1 h / 2000 ft can be replaced by:
756:
version (5 kilometres horizontally and 600 meters of ascent), not the original one (3 mi and 2,000 ft).
1263:
Mountaincraft and Leadership; A Handbook for Mountaineers and Hillwalking Leaders in the British Isles
302:. No simple formula can encompass the full diversity of mountain conditions and individual abilities.
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721:
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688:'s base speed of 5 km/h and makes the following further refinements for going downhill:
212:
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1265:(Fourth ed.). Mountain Training England; Mountain Training Scotland. pp. 38–39.
8:
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is the reciprocal of speed. It can be calculated here from the following formula:
91:
vs. slope angle resulting from Naismith's rule for basal speeds of 5 and 4 km / h.
1609:
1570:
About walking uphill: time required, energy consumption and the zigzag transition
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57:
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Wilderness Areas in Scotland, unpublished Ph.D. Thesis. University of Aberdeen
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1469:"Pace and critical gradient for hill runners: an analysis of race records"
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of ascent. It is included in the last sentence of his report from a trip.
76:
773:
250:
times and found to be reliable. Scarf proposed this equivalence in 1998.
108:
1334:
National Center for Geographic Information and Analysis Technical Report
1120:
Caleb's List: Climbing the Scottish Mountains Visible from Arthur's Seat
179:
When walking in groups, the speed of the slowest person is calculated.
172:
In practice, the results of Naismith's rule are usually considered the
166:
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84:
315:
30:
781:
1196:
Walking on the West Pennine Moors: 30 routes in gritstone country
202:
186:
158:
121:
1 h / 5 km (3 mi) + 1/2 h / 300 m (1000 ft)
45:
1291:
The Adventure Activities Licensing Regulations 2004, section 2
1287:
The Adventure Activities Licensing Regulations 1996, section 2
215:, in research published in 2008, gives the following formula:
1314:. Edinburgh Scotland: Britain & Scottish Sports Council.
769:
379:
234:
104:
100:
88:
893:(1st ed.). Singapore: KHL Printing. pp. 51–122.
63:, in 1892. A modern version can be formulated as follows:
118:
1 h / 3 mi (5 km) + 1 h / 2000 ft (600 m)
768:
Langmuir 2013 recalls the Naismith's rule from 1892 in
813:"Excursions. Cruach Ardran, Stobinian, and Ben More"
784:
sometimes per contour line on a map (10 m or 50 m).
386:
Time taken in hours estimated using Naismith's rule
1542:"FAQ - Navigation: Walking Speed - Naismith's Rule"
1083:
752:for the Naismith rule were calculated here for its
684:(1984) extends the rule on descent. He assumes the
931:"A mathematical excursion in the isochronic hills"
891:Unjustifiable risk? The story of British climbing
99:'s rule from 1892 says that one should allow one
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1238:(5 km /h (3 mph) and 1/2 hr / 300 m (1000 ft))
806:
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800:
203:Scarf's equivalence between distance and climb
157:, Naismith's rule applies only to hikes rated
1535:
1533:
1531:
1084:Magyari-Sáska, Zsolt; Dombay, Ştefan (2012).
1079:
1077:
1075:
237:/ 2000 ft), called Naismith’s number by Scarf
1590:Tranter's Correction – is it still relevant?
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1086:"Determining minimum hiking time using DEM"
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344:. Unsourced material may be challenged and
107:on the map and an additional hour per 2000
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1524:of downhill correction for Naismith's rule
1476:Journal of Quantitative Analysis in Sports
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364:Learn how and when to remove this message
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44:helps with the planning of a walking or
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1285:See definition of "travelling time" in
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14:
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153:routes. In the grading system used in
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1192:
1172:. Bradt Guides. Bradt Travel Guides.
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578:
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817:Scottish Mountaineering Club Journal
342:adding citations to reliable sources
309:
176:time necessary to complete a route.
1466:
1223:The Ultimate Hiking Skills Handbook
1137:
1003:
887:"1865–1914: gentlemen and gymnasts"
776:, but further gives and uses it in
744:
742:
137:12 min / 1 km + 10 min / 100 m
24:
1539:
811:Naismith, W. W. (September 1892).
25:
1631:
1580:An online calculator and Nomogram
1558:
1169:Macedonia; the Bradt Travel Guide
762:
1585:Naismith's Rule and Route Timing
1043:10.1111/j.1538-4632.2012.00838.x
739:
314:
1425:
1006:"Route Choice in Hilly Terrain"
190:A plot of walking speed versus
383:Individual fitness in minutes
13:
1:
929:Scarf, Philip (August 2008).
791:
219:equivalent distance = x + α·y
27:Rule of thumb for hiking time
711:+ 1 h / 450 m of ascent
72:Assumptions and calculations
7:
1325:Tobler, W (February 1993).
715:
10:
1636:
1387:Journal of Sports Sciences
1199:. Cicerone Press Limited.
854:A Lake District Miscellany
656:
1467:Kay, A. (November 2012).
1399:10.1080/02640410600874906
1340:(1): 1–24. Archived from
1117:MacInnes, Kellan (2013).
637:Too much to be attempted
609:
382:
298:walkers descend a gentle
279:p0 = pace on flat terrain
1433:"Professor Philip Scarf"
1147:. Maumturks Walking Club
732:
727:Tobler's hiking function
196:Tobler's hiking function
1439:. University of Salford
1310:Langmuir, Eric (1984).
1261:Langmuir, Eric (2013).
1226:. David & Charles.
1220:Bagshaw, Chris (2006).
970:Aitken, Robert (1977).
722:Preferred walking speed
699:Later he says that the
256:
227:x = horizontal distance
163:Yosemite Decimal System
1488:10.1515/1559-0410.1456
1166:Evans, Thammy (2010).
199:
92:
38:
1193:Marsh, Terry (2012).
1093:Geographia Napocensis
306:Tranter's corrections
230:y = vertical distance
213:University of Salford
189:
79:
33:
1095:. Anul VI (2): 124–9
885:Thompson, S (2010).
851:Holman, Tom (2010).
677:Langmuir corrections
338:improve this section
128:+ ½ h / 1000 ft
18:Naismith's Rule
1419:Also available in:
1123:. Luath Press Ltd.
1025:2012GeoAn..44...87K
857:. Frances Lincoln.
833:Available also in:
293:Other modifications
282:m = gradient uphill
54:William W. Naismith
1620:1892 introductions
1364:2016-03-04 at the
1357:Available also in
666:Aitken corrections
200:
134:+ ½ h / 300 m
93:
39:
1437:www.salford.ac.uk
1272:978-0-9568869-0-3
1145:"Naismith's rule"
938:Mathematics Today
900:978-1-85284-627-5
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16:(Redirected from
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1347:on 22 April 2008
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1053:. Archived from
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268:p = p0·(1 + α·m)
244:Bob Graham Round
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1393:(6): 719–726.
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1615:Navigation
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1443:1 February
1151:22 January
1064:19 January
1013:Geogr Anal
980:26 January
948:22 January
870:19 January
827:22 January
792:References
748:Speed and
151:scrambling
144:route card
103:per three
1496:1559-0410
1029:CiteSeerX
944:: 163–167
325:does not
85:kilometre
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1362:Archived
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1099:21 March
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823:(3): 136
782:climbing
780:system,
716:See also
686:Naismith
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300:gradient
276:p = pace
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1021:Bibcode
759:climb).
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770:miles
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570:13.25
192:slope
105:miles
1549:2013
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1492:ISSN
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774:feet
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477:14.5
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329:any
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