A recent Scientific Reports analysis of runners in the Berlin Marathon race found that a significant pace drop in the closing kilometres affected 17 percent of males, compared with 9.7 percent of females. The exact causes were not identified, but assumptions were made, in part based on outcomes and testimony from athletes.
The physiological explanations are compelling, but they may not tell the whole story.
The study is titled “Sex differences in marathon pacing: analysis of 873,000 Berlin marathon runners reveals men are twice as likely to ‘hit the wall.'”
It was published in the journal Scientific Reports.
Perhaps it is attitudinal
A possibility not fully explored is about behaviour rather than biology. Men, on average, may be more inclined to race the marathon as something to conquer. That mindset can encourage ambitious pacing and greater willingness to gamble on a personal best, even when the risk of implosion is high. Women, by contrast, may be more likely to approach the marathon as an event that demands respect rather than conquest, adopting a more measured strategy that ultimately rewards patience over bravado.
Physiology may explain part of the difference, but psychology could explain another part. Men may simply be more likely to gamble—starting a little faster, aiming for a more ambitious finishing time, and trusting they can hold on. Women may be more likely to respect the marathon’s demands from the outset, choosing a pace they can sustain. If that’s true, the wall may be as much a consequence of decision-making as of depleted glycogen.
DNFs could influence the results of the study
One question the study does not appear to address is what happened to runners who never reached the finish line. The analysis was based on marathon finishers, leaving open the possibility that some athletes—particularly those who paced too aggressively—abandoned the race before their late-race slowdown could be measured. If dropout rates differ between men and women, the findings may not tell the whole story.
Whether this matters depends on the prevalence of DNFs. At the Berlin Marathon, the DNF rate is generally low—often around 2–4% of starters—but with a dataset of more than 870,000 participants, that still represents tens of thousands of runners.
So, while excluding DNFs probably doesn’t invalidate the study’s conclusions.
From the study: “The risk disparity widened among the fastest runners: in the Competitive (< 3 h) category, male runners were approximately six times more likely to experience catastrophic deceleration than their female counterparts (1.42% vs 0.23%). The gap was stable across the 27-year archive (Mann–Kendall τ = 0.14, p = 0.33). Despite faster finish times, men demonstrate significantly less stable pacing strategies and a twofold higher crude risk of catastrophic deceleration compared with women, with the disparity most pronounced among the fastest runners. These findings are consistent with the hypothesis that behavioural and strategic factors contribute alongside physiological determinants to sex differences in marathon outcomes, and provide a quantitative basis for further investigation of the underlying mechanisms.”
The study used a 20 percent drop in pace over the second half of the race, the final 21.1 kilometres. Whereas the study references hitting the wall at kilometre 30. Anecdotally, amongst the runners themselves, 20 miles or 32 kilometres is traditionally where the mysterious wall arrives. Of course, the wilder the pacing, the sooner the wall arrives. Some athletes meet it as early as 25 kilometres.
Conclusion
The study’s findings strongly support the role of physiology in why some marathoners hit the wall, but they also leave room for another possibility: psychology. The authors themselves suggest that behavioural and strategic factors may contribute alongside biological differences. Men may simply be more willing to gamble with ambitious pacing in pursuit of a personal best, while women may be more inclined to adopt a strategy that respects the marathon’s demands from the outset.
There is also one important caveat. The analysis was based on marathon finishers, leaving unanswered what happened to runners who abandoned the race before reaching the finish. Although the Berlin Marathon has a relatively low dropout rate, excluding DNFs could influence the overall picture if pacing-related withdrawals differ between men and women.
Ultimately, the study reinforces what experienced marathoners have known for decades: the race truly begins around 30 to 32 kilometres. Whether the wall is caused primarily by depleted glycogen, overambitious pacing, or a combination of physiology and psychology, and or under- or overtraining, the athletes most likely to avoid it are often those who respect the marathon rather than try to conquer it.
