How to run the Comrades Marathon

How to run the Comrades Marathon

The Comrades Marathon is a race of variable distance, run in alternating directions between the coastal city of Durban and inland Pietermaritzburg, South Africa. When the race starts in Pietermariztburg, it is referred to as the ‘Down’ run and the other way around is the ‘Up’ run. There are five notorious hills between these two cities, which makes the ‘Up’ run approximately 56km of positive gradient, compensated for slightly by the fact that the route is marginally shorter – about 86km to the 89km ‘Down’ run.

The Comrade Marathon has been run eighty times and 76 768 people from around the globe have completed it at least once in their lives. Twenty nine (male) runners[fusion_builder_container hundred_percent=”yes” overflow=”visible”][fusion_builder_row][fusion_builder_column type=”1_1″ background_position=”left top” background_color=”” border_size=”” border_color=”” border_style=”solid” spacing=”yes” background_image=”” background_repeat=”no-repeat” padding=”” margin_top=”0px” margin_bottom=”0px” class=”” id=”” animation_type=”” animation_speed=”0.3″ animation_direction=”left” hide_on_mobile=”no” center_content=”no” min_height=”none”][1]* have completed more than 30 Comrades Marathons and 2 567 have their green number, awarded on finishing the tenth race.     The course records for the two races are 5:25 (Vladimir Kotov, 2000) and 6:11 (Elena Nurgalieva, 2004) for men and women respectively in the Up run and 5:24 (Bruce Fordyce, 1986) and 5:54 (Frith van der Merwe, 1989) for the Down run.

The Comrades Marathon as grown from a modest, amateur and intensely local event to a race with substantial prize money, sponsors, international status, a 13 hr television broadcast, four day Expo and all the carnival that goes with a big city marathon.   Between 12 and 15 000 runners enter the race each year, with the highest ever entry being over 24 000 in 2000. Of these runners, less than 20% are women and about the same proportion are novices.    In 2005 the average finish time was 10:27 minutes for women and 9:55 for men. However the average finish times for both genders have increased by an hour since 1980. The average age of competitors has also increased over the same time, from 34.0yrs in 1980 to 41.6 yrs in 2005.

Table 1: Number of finishers and average times and ages of Comrades Marathon competitors from 1980 to 2005

Number of women Mean Finish Time (hr:min:sec) Number of Men Mean Finish Time (hr:min:sec) Age (yrs)
1980 33 09:23:51 3946 08:57:54 34.0
1981 59 09:43:49 3602 09:08:54 34.5
1982 99 09:42:53 4501 09:05:26 34.6
1983 157 09:49:04 5207 09:13:28 34.1
1984 260 09:42:07 6843 09:09:37 33.9
1985 300 09:54:52 7892 09:24:59 34.8
1986 431 09:45:50 9223 09:12:51 35.0
1987 407 09:59:37 7969 09:29:14 35.4
1988 544 09:57:00. 9819 09:23:17 35.6
1989 671 09:56:57 9835 09:28:57 35.6
1990 647 09:56:45 9626 09:27:53 34.8
1991 921 09:52:38 11160 09:25:58 35.1
1992 868 09:59:01 9827 09:30:05 35.3
1993 1098 10:01:49 10223 09:27:07 35.9
1994 1078 10:01:28 9195 09:33:07 36.2
1995 1185 10:05:12 9356 09:37:25 36.3
1996 1232 09:57:24 10035 09:28:30 36.8
1997 1367 10:00:55 9989 09:32:22 37.1
1998 1285 10:05:46 9211 09:37:13 37.3
1999 1458 10:01:28 9757 09:33:38 37.7
2000 3311 10:47:12 16729 10:13:49 38.0
2001 1661 10:06:46 9419 09:34:33 38.1
2002 1186 10:05:11 7843 09:33:49 38.6
2003 1869 10:25:11 9545 09:50:28 39.6
2004 1564 10:33:45 8558 09:57:34 39.7
2005 2014 10:27:51 9710 09:55:52 40.2


Medals are awarded according to finish time: the first ten men and ten women earn gold medals. Runners finishing in under 7H30 earn a silver medal, under 9hrs a silver/bronze (called the Bill Rowan medal), under 11 hrs a bronze and under 12 hrs a copper medal (named the Vic Clapham medal). Bill Rowan was the winner of the first Comrades Marathon in 1921, in 8:59, and Vic Clapham the founder of the race.   The proportion of finishers in each medal category in the 2005 race is shown below.


Table 2: Number of medals in each category according to seeding position at the start

Gold Silver Bill Rowan Bronze Vic Clapham DNF Total runners
A 19 525 428 125 18 142 1257
B 1 94 914 324 35 113 1481
C 10 795 1102 101 195 2103
D 5 234 1945 292 293 2769
E 12 374 303 197 886
F 24 1155 593 283 2055
G 12 534 847 386 1779
H 3 1 146 737 580 1467
Total 20 637 2420 5705 2926 2189 13897

 13897 entered, 12 938 started and 2189 Did Not Finish (16.9%)

Runners have to qualify to run the Comrades marathon by completing a standard marathon in under 5 hours, or another ultra distance race where the cut-off time is dependent on the distance. Runners are then seeded for the start according to their qualifying times (Table 3).

Table 3: Race distance, qualifying time and seeding batches for the Comrades Marathon

Batch  42.2 km  48-50 km  52-54 km  56 km  60 km  64 km  80 km  89km  100 km
A  3:00:00  3:40:00  3:55:00  4:05:00  4:30:00  5:00:00  6:20:00  7:30:00  8:15:00
B  3:20:00  4:00:00  4:20:00  4:35:00  5:00:00  5:30:00  7:00:00  8:15:00  9:15:00
C  3:40:00  4:25:00  4:45:00  5:00:00  5:30:00  6:00:00  7:40:00  9:00:00  10:15:00
D  4:00:00  4:50:00  5:10:00  5:30:00  6:05:00  6:40:00  8:30:00  9:45:00  11:00:00
E Green Number Club (all runners who have completed ten or more races)
F  4:20:00  5:10:00  5:35:00  6:00:00  6:40:00  7:15:00  9:15:00  10:30:00  11:45:00
G  4:40:00  5:35:00  6:05:00  6:30:00  7:10:00  7:50:00  10:00:00  11:15:00  12:30:00
H  5:00:00  6:00:00  6:30:00  7:00:00  7:40:00  8:20:00  10:40:00  12:00:00  13:30:00


Competitors wear a timing chip, and there are timing mats at five points along the route.   It is a ‘gun to gun’ race in that all competitors start at the same time, and their finish time is taken as being from that time and not the moment the runner actually crosses the start line. It takes approximately seven minutes to clear the start, that is for the last runner to cross the line.   There are cut-off points along the route, the first one being at half-way. Any runner failing to reach this point in 6 hrs is not allowed to proceed. Likewise they have to get to 70km in 10 hrs and 80km in 11 hrs to continue. The cut-off times are there in part to ensure runner’s safety: by 5.30pm (the 12 cut-off) it is dark and the race route is no longer closed to traffic.   A sad and sore number of athletes make it past the 80km cut-off point in the gathering dusk but still don’t reach the finish line on time.


The use of electronic timing systems and immaculate record-keeping by an IT company contracted to the Comrades Marathon Association has generated a wealth of numbers for analysis and some research. However, little is known, other than anecdotally, about how runners prepare for the Comrades Marathon or what they do and experience during the race.  In 2005 the author compiled a questionnaire to establish what training and race strategies Comrades Marathon runners employ.   The questionnaire was placed on the Comrades Marathon website and it was intended that runners visiting the site to check their results after the race would respond to the invitation to complete the questionnaire.


This questionnaire has generated the first ever substantive set of data about runners’ race preparation and experience. This, together with an rigorous analysis of race splits, qualifying times, body weights and other demographic factors form the basis of this report and help to answer the following questions:

  • how to train for the Comrades Marathon
  • how to predict performance in the Comrades Marathon
  • how to manage the race, and
  • why do women do it better ?

Demographic data of the runners who completed the 2005 Comrades Marathon questionnaire

There were 613 respondents, which is 4.4 % of all those who registered for the 2005 race. Of these respondents, 47 provided an incorrect or no race number and were discarded from the analysis. There were 143 women runners (25.3% of all respondents) and 433 men. There is a higher proportion of women in this sample population (25.3%) than entered the 2005 race (17.1%). Furthermore, the average time for these women is 10hrs18 mins, while the average time for all women finishers in the 2005 race is 10h27mins. In contrast, the average time for the men who completed the questionnaire is slower than of the whole field – 10hr 13 mins compared to 9hrs 55 mins. These differences are not statistically significant. Twenty three respondents did not complete the race, which is 4.1% of the sample. Of the 13 897 runners who registered for the 2005 Comrades Marathon 15.5% did not finish, so the questionnaire sample under-represents the failures. This is to be expected in that those who complete the race are more likely to visit the website to check on their and others results and therefore complete the question, than those who did not finish.


The mean age of the men was 41.9 years old and the women 39.4 years. The men had been running for 11.1 yrs and completed 5.6 Comrades marathons with an average best time of 09:31:10 while the women had 8.8 years running experience and 4.3 Comrades behind them with an average best time of 10:09:32. Only the average best Comrades marathon times for each gender are significantly different, as would be expected.

Table 4: Demographic data of the study sample of 566 runners who completed the 2005 Comrades Marathon


< 07:30

n = 14

< 09:00

n = 62,19

< 10:00

n = 69, 32

< 11:00

n= 156, 54

< 12:00

n= 100, 32


n= 16, 7


n= 423, 143

Years running Men (yrs) 11.5± 5.8 12.1±10.2 12.0± 9.2 11.4±8.5 9.9 ± 8.4 9.2±6.7 11.1±9.0
Years running Women (yrs) 9.2 ± 5.5 9.1± 5.7 9.1± 7.2 7.6±6.4 6.7±+6.4 8.8±+ 6.7
Body Weight Men (kg) n=1652 66.1±7.8 69.7±11.5 72.6±10.6 77.4±12.3 78.2±16.1 74.3±11.3
Body Weight Women (kg) n=326 56.3±+4.6 58.6±5.9 59.7±6.7 62.8±8.8 59.7±7.1
Number Comrades MarMen 5.6 ± 4.9
Number Comrades Women 4.3 ± 4.0


Note: Only 15 women achieved silver medals in the 2005, of which 10 also won gold medals (awarded to the top 10). As this group is so small, no analysis is presented thereof, and the data for these women in included among all those who finish in under 9 hrs.



Given the status and the history that the Comrades Marathon occupies among South African runners there are as many myths and legends of training as there are reliable strategies. Everyone knows someone who has run the race and has either done extraordinary, enough or very little training and the tendency is to believe that these individuals’ experience is representative of all runners. There are also the folk lores that are bred in running clubs and families and work places and hybrid training programmes that emerge from these collective experiences. There is an ‘official’ Comrades training programme designed by Don Oliver, which is endorsed by the Comrades Marathon Association (CMA) and appears on it’s website and in the SA edition of Runners’ World. Bruce Fordyce has also published various programmes as have other former medallists and just about anyone with any street cred – and also those with very little. Don Oliver’s programmes are conservative, realistic and manageable for those with some running experience and a good dose of motivation.   He has different strategies for different abilities and target times, but all have the athlete completing 1200 to 1600km between January 1 and June 15, including two standard marathons and three ultramarathons. This has become the ‘gold standard’ of sensible Comrades training, the total mileage that a runner wishing to complete the race successfully should be prepared to invest.

So what do runners actually do?   The 431 men and 143 women who completed the questionnaire did 1131 and 1191km respectively between Jan 1 and June 15 2005.   Moreover, less than 50% of them followed a specific training programme. On average, they completed less than 4 runs of 30-40km, fewer than 3 runs of 40-50km, one run of 50-60km and less than 30% went further than 60km in a single training run. There were no differences between the men and the women in the total mileage or proportion of long runs. However 52.3% of the men and 37.6% of the women reported that they had been unable to train for more than a week due to illness or injury or both. This is a statistically significant difference.

The correlation between total mileage and finish time for all runners is r = 0.5385 (p < 0.01), which highly significant. It also suggests that 29% of the finish time can be explained by training mileage
(r2 = 0.28999). Given that mileage does count, there is also an expected significant difference in total training mileage for each medal category, as shown below.   Men who achieve a silver or Bill Rowan medal run significantly more kilometeres in training than do men in all other medal groups and the silver medallists were twice as likely as any other group to follow a specific training programme. Similarly, women who finished in under 9 hours did significantly higher mileage than all other women finishers, but they were the least likely of all groups to follow a training programme.   There are no differences between genders or medal categories in the number of long training runs completed, except that the male silver medallists did more 30-40km runs than any other group.

Table 5: Training mileage and breakdown of the study sample who completed the 2005 Comrades Marathon


< 07:30

n = 14

< 09:00

n = 62,19

< 10:00

n = 69, 32

< 11:00

n= 156, 54

< 12:00

n= 100, 32


n = 16, 7


n = 423, 143

Mileage Men (kms) 1750+659 1417+557 1307+506 1102+376 937+398 1114+347 1131+488
Mileage Women (kms) 1438+13 1340+ 86 1125+307 1036+305 929+260 1191+525
Runs 30-40km Men 7.1 5.0 4.4 3.6 3.0 3.8 3.8
Runs 30-40km Women 4.3 4.5 4.3 3.5 3.7 5.0
Runs 40-50km Men 3.7 3.3 3.0 2.6 2.8 2.3 2.7
Runs 40-50km Women 2.6 2.8 2.9 2.5 1.6 3.1
Runs 50-60km Men 1.9 1.3 1.3 1.1 1.1 1.1 1.2
Runs 50-60km Women 1.7 1.4 1.2 1.1 0.7 1.5
Runs > 60km Men 0.4 0.4 0.5 0.2 0.2 0.3 0.3
Runs > 60km Women 0.4 0.2 0.3 0.2 0.3 0.4


As this is the first comprehensive description of the training of average Comrades Marathon runners there is little to compare it to. In 1970, 140 Comrades runners reported that they had, on average, run 1734km from January 1 to May 30.   Those with the fastest times (6 to 6.5 hrs) had done 2574km and the 10 to 11 hrs finishers 1030km.   This is the same as the average mileage of 566 runners in 2005!   The current elite runners claim to run in excess of 3000 to 3500 km in preparation for the marathon, which is similar to what runners were doing twenty years ago.


While the 1970 data may be incomplete and even inaccurate it may in part explain the steady decline in Comrades Marathon finishing times (see Table 1) and the higher rates of attrition during the race since 1980.     In 1984, a 91.4km Down run, 96% of the starters completed the race. Since that record success, the ‘pass rate’ declined to 72% in 2002. The following year the cut-off was extended from 11 to 12 hrs and this has allowed more runners to complete the race each year since – up to 90% in 2005. Interestingly, many of them are ‘green numbers’ which means they must have finished at least ten races within the old limits but now take advantage of the extra hour.


The combined evidence of decreasing finishing times, (until recently) increasing failure rates and increasing average age suggests the Comrades Marathon runners are getting steadily more middle-aged and not doing the training volumes that runners, including perhaps themselves, did ten and twenty years ago.   There is also a pervasive attitude that you don’t have to train that much to walk to Durban (or Pietermaritzburg) in 12 hours, but at the same time you must not undertake such an arduous journey when you are young – that is less than 30! The result is that the Comrades Marathon has been described as ‘watching middle aged men walking’.


Despite their high training load the male silver medallists were the least likely to have spent a week off due to injury and illness (28.6%) – but then the corollary is that this would have allowed them to complete a higher total mileage. The majority of the men who finished in over 10 and over 11 hours (76% and 58% respectively) had been unable to train due to injury or illness. Likewise, the women who finished in under 9 hrs had the least compromised training (15.1% were unable to train for a week or more) while up to 50% of the women in all the other medal groups had been affected. Six of the seven women who did not finish had been ill and/or injured and their total training mileage was lower than any other group in the study.

There were no significant differences between genders within each medal category with regard to total mileage. The range of training mileages reported vary from 350km to 2160km for the women and 150km to 3500km for the men. However there is some doubt as to the validity of the exceptionally low mileages (< 300km) reported by some runners. They may have interpreted the question to mean their average monthly mileage and not total mileage from January to June. Also, many runners stated their mileage to be ‘1000km’.   This probably reflects and estimation based perhaps on their average weekly mileage or what they thought was the appropriate mileage. Therefore this data may be skewed for several reasons: (i) runners misinterpreting the question, (ii) runners under or over-reporting mileage because no accurate records are kept, (iii) runners over-reporting mileage according to what they think they ought to have done, (iv) runners simply guessing their mileage in order to complete the questionnaire quickly, or (v) runners under-reporting mileage because they regard doing as little as possible as admirable.

The overall conclusion from the training data is that Comrades Marathon runners train less than would be expected based on historical anecdotal evidence, prescribed training programmes and basic training principles, but that the silver and Bill Rowan medallists completed significantly more miles than the rest of the field.

Predicting finish times

The most accurate way to predict a finish time is from prior performances in shorter events. This relationship certainly holds for middle distance races, even up to the marathon, but in ultra distance event there are many more variables are involved and so predictions based on any prior performances become less certain.

More than 60% of runners qualify for the Comrades Marathon over the standard marathon distance, with the majority of the remainder using a 50/52km or 56km race as their qualifier.   Less than 10% use a race longer than 60km.   The correlation between average qualifying time over three distances (42km, 50km and 56km) and finish time, for both genders is shown in the table below.

Table 6: The correlation between qualifying time and Comrades Marathon finish time according to qualifying race distance


Average Qualifying Time Comrades Marathon Finish Time Correlation
Men 42km 3:46:42 9:57:55 r = 0.789
Men 50km 4:39:08 9:49:46 r = 0.772
Men 56km 5:19:53 9:51:22 r = 0.851
Women 42km 4:08:51 10:29:59 r = 0.824
Women 50km 5:02:23 10:24:03 r = 0.828
Women 56km 5:49:36 10:26:53 r = 0.84


Not surprisingly the longer the race the closer the match between the two events.   However, what is interesting is that there is a higher correlation between performances in shorter events and the Comrades Marathon for the women than the men.   This suggests that women are able to perform more consistently over all race distances than men, that is in very long runs the men’s performance deteriorates more relative to their marathon times, than do women.

While many runners do the Comrades marathon ‘just to finish’ others train for, speculate on and purchase pacing schedules for specific finish times, or at least medal colour. Therefore a formula to calculate predicted finish time has more than academic value.   For many years the value ‘2.42’ has been touted as the magic number which, when multiplied by one’s qualifying marathon time reveals a probable Comrades Marathon finish time. It is even used by the CMA to set the qualifying time standards and seeding batches.   However this number has a dubious origin in the 1980’s, having been derived by dividing the best Comrades Marathon times of a small group of nine elite distance runners, including the male and female winners of the race, by their personal best marathon times. The resultant formula was therefore not reflective of the majority of the field.

Looking at the 2005 data, the division of finish time by standard marathon qualifying time yields a value of 2.53 for women and 2.62 for men.   However, this formula does not hold for the very fast male or the slowest runners. For men with a sub-3 hrs marathon (and therefore seeded in ‘A’), the ratio is 2.75 and for the slowest runners (batch H, both genders) the ratio is 2.4. What skews the ratio upwards for the faster runners is the high rate of attrition in this group.   Less than half of the A seeded men (43.3%) achieve silver medals.   This perhaps illustrates just how difficult the Comrades Marathon is: a person who can run at, or around 4mins per kilometer for 42km is not able to run at 5mins per kilometer for 87km (Table 2).   The A seed runners are also those who have completed the most training mileage and yet this group is least successful at achieving their presumed medal goal.   In contrast, for those runners with qualifying times slower than 4h40 mins (H group) the relationship between marathon and Comrades times is much closer. This is probably because (i) these runners do all races, regardless of distance, at a similar pace and (ii) the slowest runners are likely to miss the cut-offs along the route and therefore not finish, thereby skewing the data.

Another variable in predicting race outcome is the number of Comrades Marathons a runner has completed. Analysis of the race histories of four hundred runners (two hundred of each gender) who have run ten or more races shows that they run their personal best time on their fifth race, at an average age of 37.   There is a strong positive correlation between age and best time and a slightly weaker negative correlation between number of races and best time. From this, one can conclude that age and experience do count!

Managing the race

After the training comes the tapering, carbohydrate loading and strategy planning.   While the merits of carbohydrate loading can be debated, having a race plan for an event of such a distance over a challenging terrain is surely an advantage. Pacing charts for each medal category (except silver) are available at the Comrades Marathon Expo. These have been compiled by Don Oliver, the Comrades coach and based on his own experience of nineteen runs, refined annually by feedback from runners who have used them and analysis of the race results. These pacing plans are conservative and take into account the gradients of the five major hills and the fact almost everybody will slows down in the second half.

Of the 566 runners in the 2005 Comrades sample, less than half of the men and women used a pacing chart of any description.   There was also no difference in chart usage between the medal groups.   This apparent non-use of pacing strategies suggests either that (i) runners approach the Comrades marathon with the attitude that they will ‘run how they feel’ and be satisfied just to finish,   (ii) or they have found pacing charts to be unhelpful in the past either because the chart or they were unrealistic, or they had a bad race or (iii) they believe that somehow the race, the route and unspecified others will take care of them and they don’t engage in any specific pre-race planning or strategizing during the race.

In the 2005 race, 206 (9.3%) women and 1004 (9.4%) men did not finish, 114 and 37 respectively failing in the last hour. That is, they passed 80km before the 11 hr cut-off but could not complete the last 8km before the 12 hour final gun. Given that the race is rarely run on even splits (first and second half in the same time), all those who pass halfway in over five and a half hours face a high likelihood of failure. Forty five percent of the men and almost 90% of the women who did not finish went through halfway in over 5hrs 30mins. So a slow pace, which includes substantial amounts of walking is one ‘failure factor’.

The duration of the race is such that maintaining an appropriate fluid and fuel intake and delaying the onset of fatigue and pain as long as possible are crucial.   Given that most runners are on the road for ten to twelve hours, what, and how much to drink and eat during that time is a major challenge. Sports drinks and coca cola with their sweet flavour and carbohydrate content are hard to ingest continuously. Decreased rates of gastric emptying and high fluid intakes also suppress the desire to consume any solid food, although plenty is supplied along the route: potatoes, biscuits, jelly sweets, chocolates, oranges and sandwiches. Energy gels in satchets are popular portable carbohydrate supplements, but it is also difficult to ingest sufficient of these because they are such a concentrated source of carbohydrate with a somewhat mucoid texture.   It is also astounding that, despite widely available information and strong marketing strategies by sports nutrition companies, most athletes are not aware of their fuel needs and make significant errors both before and during the race.

For example, of the 566 athletes who completed the post Comrades 2005 questionnaire, 77.1% had ‘carbohydrate loaded’ in before the event.   The duration and composition of this carbohydrate loading is not known, and may simply have been extra servings of hotel food or systematic attempts to consume one o the several brands of high carbohydrate (10-15%) commercial sports drinks. A slightly higher percentage of the women (82.3%) than the men (76.1%) carbohydrate loaded, but the difference is not significant.

During the race, 78.8% of runners consumed the official Comrades sports drink and 62.7% used coca cola, both available at every aid station. 90.9% also drank water. Energy gels (corn-syrup) was used by 58.4% of runners, while only 18.2% used energy bars. There were no differences between the gender. However, 63.8% of female runners and 54% of male runners consumed the food provided at the aid stations – this is a significant difference and will be discussed more later (p = 0.03). The spectator interest in this race is high and many runners have supporters along the route, from which 15.7% of them also obtained preferred drinks or foodstuffs.

The body weights of 1978 runners were recorded the day before and at the finish of the race, as part of a study on hyponatraemia by the Sport Science Institute of South Africa. The data are shown in the table below.

Table 7: The pre and post-race body weights of a sample of runners participating in the 2005 Comrades Marathon

Body Weight pre-race (kg) Body Weight post-race(kg) Body Weight Difference(kg) Percent body weight*
All Men n = 1652 74.3 ± 11.4 70.9 ± 11.1 3.4 ± 2.26 4.59 %
All Women n = 326 59.7 ± 7.13 58.0 ± 8.88 1.71 ± 1.68 2.87 %

* body weight difference as a percentage of pre-race body weight

If one assumes the difference in body weight reflects sweat loss in litres, then the women and men in this sample remained remarkably well hydrated during such a long event in temperatures averaging 24oC and approximately 65% humidity.   In fact, 29 of the women (8.9%) and 36 of the men (2.2%) remained the same or gained weight, although some of this may be contributed to by the differences in attire they were wearing at the time of the two weighing sessions.   That fluid loss amounted to 2.87% in the women and 4.65% in the men is highly significantly different (p < 0.01). The fluid loss and percent body weight loss was however consistent within the medal groups for each gender. That is, the faster and lighter men and women remained as hydrated as the slower and heavier runners. This is important because it is widely believed that the faster runners are at greater risk of dehydration and the slower runners of over-hydration.

There are also significant differences in the body weights of men and women in the different medal categories (Table 4). The women who finished in under 9 hrs weighed significantly less than those finishing in over 10 hrs, while the silver medal men weighed significantly less than all other male runners.   Moreover, the men who finished in the last hour were significantly heavier than all other male runners.

The Comrades Marathon is broadcast live on South African television, and during the 13hrs of coverage there are many sorry examples of limping, cramping, vomiting and collapsing runners played out for spectacle value. However exactly how many runners experience the characteristic tribulations of ultra distance running – cramp, nausea, fatigue, pain, dizziness, diarrhoea and vomiting – is unknown.   The runners who completed the 2005 questionnaire sample reported the following incidence of each problem.   In the questionnaire ‘pain’ was that associated with a specific site or injury (that is not just ‘sore legs) and ‘fatigue’ was defined as being of sufficient magnitude that the runner believed, at the time, that they could not continue the race.

Table 8: The number of runners in the 2005 Comrades Marathon sample who experienced characteristic problems associated with endurance running events

Cramp Nausea Vomiting Dizziness Diarrhoea Pain Fatigue

ALL n=566

142 102 43 74 16 128 76
% ALL 25.4 18.2 7.7 13.2 2.9 22.9 13.6
MEN n = 423 112 74 28 55 11 99 60
% MEN 27.0 17.8 6.7 13.3 2.7 23.9 14.5
WOMEN n=143 30 28 15 19 5 29 16
% WMN 21.3 19.9 10.6 13.5 3.5 20.6 11.3


There was no significant difference between the percentage of men and women experiencing any of these events.   However, within each gender there are some telling variations. The data was analyzed according to finish time: sub 7h30, sub 9, 10, 11 and 12hr and DNFs. A higher percentage of male silver medallists experienced cramp (42.9%), nausea (21.4%) and diarrhoea (7.1%) than any other group, but they also had the lowest reported incidence of pain and fatigue.   The women who completed the race in under 9 hrs also cramped more than any other group (31.5%), but reported less nausea (10.5%) and vomiting (0%) than the other women finishers[2]*

This data is interesting because it suggests that cramp is not the fate of the lesser trained heavier male runner, as is commonly suggested, but rather men and women with relatively low body weights who are well trained and running at a high intensity relative to ability. The silver medallist men also had more problems with nausea and diarrhoea than the top women runners, which may contribute to the differences in performance discussed later.   That the relatively elite men, who run the entire race at or below 5mins per kilometer reported considerably less pain and fatigue than any other males runners (7.1% compared to an average of 23.5%) is probably the most sterling evidence for the value of training – and good genes!   Or, it could be because the 48% of ‘A’ seeded runners who do achieve a silver medal are those who, through training or luck don’t get as sore and tired as those who fail.

Twenty three runners in the sample group did not complete the race. Seven bailed before halfway (44km), and four failed to complete the race having passed the final check point.   The seven women were all slow runners (seeding batch H) but the men were from all seeding batches. Among this group there was a three times greater incidence of vomiting and diarrhoea, twice the incidence of dizziness and half the incidence of severe pain than for the rest of the sample. However given the small sample size, the ratio’s may be exaggerated.   It does suggest though that DNF runners, mis-managed their fuel and hydration strategies, as these are the most common causes of nausea, vomiting and diarrhoea during prolonged exercise.

Women do it better

In a standard marathon or shorter race one can reasonably expect to run even, or close to even, splits. The elite runners even do it backwards – faster in the second half. Very few runners achieve this in an ultra marathon, especially one as long and undulating as the Comrades Marathon. In the 2005 race, the top five men and the winner of the women’s race managed the magic reverse split. Thereafter only 33 women (1.69%) and 264 men (2.77%) ran negative splits.

Table 9: Finish time and first and negative half split times for all runnrs completing the 2005 Comrades Marathon (n = 10749)

Finish Time First Half Second Half Additional time*

All Men

09:55:22 04:32:19 05:23:10 00:50:58
  01:23:55 00:42:15 00:47:58 00:34:31
All Women 10:27:52 05:00:23














Men < 7:30 7:00:27 3:14:25 3:46:02 31:36
Women < 7:30 6:58:04 3:24:16 3:33:48 10:06
Men < 9:00 8:26:57 3:50:37 4:36:20 45:43
Women < 9:00 8:33:19 4:08:18 4:25:01 16:43
Men < 10:00 9:34:12 4:20:53 5:13:20 52:27
Women < 10:00 9:37:37 4:37:36 5:00:00 22:24
Men < 11:00 10:34:34 4:50:52 5:43:26 52:40
Women < 11:00 10:34:04 5:04:41 5:29:23 24:21
Men < 12:00 11:35:53 5:19:07 6:16:47 57:40
Women < 12:00 11:34:37 5:29:02 6:05:34 36:32

* Additional time taken to run the second half of the 2005 Comrades Marathon


Looking at Table 9 (above) three striking features emerge:

  • the substantial difference between the first and second half splits in all medal groups . The slower the finish time the greater the difference between the time taken to run the first and second halves.
  • On average, the men take nearly 51minutes more to complete the second half of the race, whereas women take 27 minutes.
  • For every level of ability (medal category) women run the second half 10 to 15mins faster than the men.   Moreover, because they go through halfway in a slower time than the men who finish in the same hour, the overall difference between the time men and women take to run the second half is between 20 and 30 minutes. For example, the men who run under 9 hrs go through halfway in 3:50:57 but then take an extra 45mins to complete the second half (4:36:20). Women go through halfway 18 minutes slower (4:08:18) but then take only 16 minutes longer to do the second half (4:25:01). Thus not only do the women run the second half faster, there is a 30 minute discrepancy between the genders in the second half. Similar relationships exist in all other medal groups.

What does this tell us ? If the ability to run an ultra-marathon at an even pace and finish comfortably is regarded as a sensible strategy and worthwhile goal, then women do it better than men.   The fact that women run entire race at a more constant pace, and don’t deteriorate as much as the men also explains why women run a Comrades Marathon time that more closely matches their standard marathon time and why a slow female runner (marathon greater than 4:30) has a better chance of finishing within the 12 hr cut-off than an equally slow male runner.

So what is it that gives women the edge in ultra endurance races? There are several possibilities, none of which have been conclusively proven and all of which probably contribute to varying degrees.

  1. The obvious explanation for the difference between the genders would be that the women go out slower and then have more for the second half having conserved both their physical and mental energies.   They tend to be more realistic about their finish time (relative to ability) and set their targets based on pre-race evidence, not past history, illusions of negative splits and training mates’ expectations and provocations. Women tend to trust their abilities less, and while this may be construed as timorous perhaps in distance races being less confident is an advantage because you don’t take the risks in the first half that end in shuffling and tears with 20km to go.
  2. Women are physically smaller, so they have to expend less fuel shifting their bodies over any given distance.   This has to be an advantage when fuel becomes a potentially limiting factor, as it does in ultra distance running where it is difficult to match intake to expenditure.
  3. However, it appears from this study that women manage their fuel intake better than men, consuming more before the race (82.3 % carbo-loaded) and ingesting sports drinks, gels, energy bars and importantly, food, during the race.   The women made significantly more use of the food provided at the aid stations than did the men.   Therefore, one can conclude that because women burn less carbohydrate per unit time, and also ingest more than the men they do not become as carbohydrate depleted in the latter part of the race. This could substantially explain their ability to maintain their pace in the second half of the race.
  4. Women are not as hot. Being smaller with less muscle mass they generate less heat and because of their greater surface area to body weight ratio they also loose heat more efficiently. This is a critical advantage in prolonged exercise in a warm environment where a rise in body temperature will limit exercise capacity in order to protect the body from reaching dangerously high internal temperatures.
  1. Women also drink more. In the 2005 Comrades marathon study, the average body weight difference from the day prior to the finish line was 1.71 kg – 2.87% of their pre-race body weight. If this represents fluid (sweat) loss, then the women remain incredibly well hydrated given the duration and environmental conditions of the race. In contrast, the men lost 3.4kg which is 4.59% of their initial body weight.   Staying well hydrated ensures that circulating blood volumes are maintained. This aids with thermoregulation primarily but also ensures that there is sufficient blood flow to exercising muscles and to the gut. In conditions of low circulating volume blood flow to the gut is limited, while the skin and muscles compete for the remaining volume, leading to an inevitable deterioration and even cessation of exercise capacity.
    Remaining hydrated means that the women runners (i) get less hot, (ii) maintain blood flow to the legs and (iii) have enough blood still going to the gut to allow for adequate fuel and fluid absorption, thereby further enhancing all of the above. In contrast, the more dehydrated one becomes, the less able one is to maintain hydration, fuel intake and body temperature. So the female runners advantage here is a win-win situation all round!
  2. Women hurt less – well theoretically anyway. Again, due to their smaller frame and lower mass women may experience less repetitive impact stress than men. As this is a primary cause of muscle damage and pain during prolonged exercise, being less sore would mean that women would be able to continue running when larger heavier males would be reduced to a stiff legged limp.   Oestrogen is thought to play a role in protecting tissue, including muscle tissue, from the damaging effects of free radicals produced during metabolic processes. As these are accelerated during exercise, there is increased free radical damage to all cells, so anything that contains or destroys free radicals will potentially reduce damage and the associated pain. So while it is possible that women would experience less exercise-induced muscle damage due to their having oestrogen, this never been conclusively demonstrated in humans, only rats.   In this study, the 23.9% of the men and 20.6% of the women reported having experienced pain associated with a specific site or injury. Fatigue ‘sufficient to make them think they could not continue’ was endured by 14.5% of the men and 11.3% of the women. So it would seem from this evidence that oestrogen doesn’t help during the race but may reduce the post-race agony and inability to descend stairs.
  3. Women think differently. Ultra-marathon running is intensely physically and mentally demanding, so being able to cope with this high level of stress is key to successful performance.   Little research has been done on the appraisal and coping patterns of endurance athletes but a recent study has shown men and women conceptualize and deal with the unique pressures of endurance racing differently. In this study on ironman triathletes and marathon runners both genders exhibited the same degree of anxiety before the race about the same factors: the environmental conditions, the course, their race strategy and their ability.   However the difference was that the women perceived that they had less control over these factors than did the men. Thus, during the race men employed a coping strategy that was intended to reduce the external and internal threats, while women tended to employ more emotion-focused coping strategies. They attempted to positively re-interpret their situation, seek social support and dissociate from what they were experiencing while men employed a ‘problem-solving’ approach while women used a more ‘emotion-focused’ technique.

In a race of the duration and difficulty of the Comrades Marathon both strategies are useful and necessary, but perhaps the women are better socialized to benefit the most from the spectator support and the camaraderie of fellow runners. The Comrades Marathon is probably unique among ultra-endurance events in the extent and depth of spectator participation. It can become overwhelming at times but there is no stretch of the long road that does not have enthusiastic and generous supporters making every runner feel like a hero for that one day. Those runners who can tap into this energy while maintaining their focus on the practicalities of the race have an advantage that is not measurable.

Thanks to the Comrades Marathon Association, Graeme Vincent of Mr Price Group (IT) and the Sport Science Institute of South Africa for all data.

Words: 7000

[1] Until 1975 women and black persons participated in the marathon unofficially, and their finishes were not formally acknowledged

[2] All data not shown due to the extent and complexity thereof[/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]