Ed Caesar almost broke the 2 hour barrier for the marathon last Sunday at Edinburgh’s Footworks running store. All he had to do was stay on the treadmill – pre-set to sub-2 hr marathon pace − for another 1:57:55. But with customers wanting him to sign copies of his bestselling Two Hours: The Quest to Run the Impossible Marathon, Ed did the decent thing and stepped off after 2 min 04 sec.

Next up, Scottish international ultrarunner Dr Andrew Murray − Sport and Exercise Specialist at the University of Edinburgh − endured the punishing pace for 5 min 02 sec. As Ed Caesar notes in Two Hours: ‘By 2012, the elite no longer considered the marathon a pure endurance event. It was a speed-endurance event.’ This is underlined by Caesar’s account of a brutal training session he witnessed in the Kenyan village of Kapng’tuny while staying with Geoffrey Mutai, who set a world best of 2:03:02 in 2011. Mutai supervised a 13-mile speed session involving 18 two-minute sprints and ‘sometimes Mutai and the strongest men would sprint so fast that they overtook the 50cc motorcycle I was riding.’

When Dennis Kimetto’s world record of 2:02:57 eventually falls it will probably be claimed by an East African. Refinements in training, diet, shoe technology, pacing, wind protection – an athlete shielded by a pacemaker running at 2-hr pace saves 100 seconds – and financial incentives will play their part.

So too will the mind.

The placebo effect makes us respond positively to substances lacking active ingredients. Could it make athletes run faster? University of Glasgow researchers recruited club-standard endurance runners who self-injected themselves with saline while believing they were taking a legal form of the performance-enhancing drug EPO. The runners’ times improved by 1.2 per cent.

Lead author of the study Dr Ramzy Ross, an Exercise Physiology and Performance Specialist, told the Herald: ‘There would be a significant role for such a practice in enhancing factors such as pacing strategy, for example. Such placebo interventions could be useful both in competition and during training in relation to training intensity and/or duration manipulation. Individuals can experience through such an intervention, a reduced perception of physical effort for a given intensity; increased potential motivation during competition; and increased in perception of recovery both during training and after races. These could positively contribute to a sub-2 hr marathon. However, further study is needed on the transferability of such placebo interventions to world-class athletes.’

Ross acknowledges an ethical dimension: ‘It’s clear that under such a situation, an individual would perceive him/herself to be taking a performance enhancing substance and would have had to agree to do so. So the intention to gain an advantage over the competition would have been committed and is arguably unethical. On the other hand, in relation to coaches trying to elicit an ergogenic placebo effect from their athlete, it could also be argued that coaches are simply carrying out their remit to use all legal means possible to get their athlete to perform at their best, in this case, attempt to break the 2hr marathon barrier.’

The boundary between legality and ethics concerns Carwyn Jones, Professor of Sports Ethics at Cardiff Metropolitan University: ‘My objection centres on the twin issues of consent and deception. For the placebo to work athletes must believe they’re being given a drug, so a lie has to be told at some point, which raises medical ethical concerns around the professionals involved with the athlete.’

Scottish Olympian Donald Macgregor who finished seventh in the 1972 Munich Games marathon is clear: ‘Athletes are not to be used as guinea pigs. Each athlete has the potential to get the best out of him or herself by visualisation, suitable preparation, diet, training etc. Personally, I would have refused to accept injections, no matter how innocuous. Athletics is a sport and should remain so. I believe the 2-hour marathon will be achieved, perhaps within a couple of decades.’

Triathlete Dr Danica Bonello Spiteri, who represented Malta at the 2014 Glasgow Commonwealth Games and who worked in the city as a Sport and Exercise Medicine specialist says that elite athletes are already able to push themselves to the limits, and giving them placebo treatment is not the ideal way to improve performance: ‘If the elite athlete eventually learns about the placebo treatment, the doctor/coach-athlete relationship of trust is broken, will not be easily fixed and hence will disrupt the athlete even further. At the end of the day, the psychological aspect of the athlete is the one that is being improved upon through the placebo administration, so it would make more sense to include a sports psychologist as part of the team surrounding the athlete in the first place, as the mind is in control of elite athletes’ performances.’

Andrew Murray says, ‘I suggest the placebo effect is less effective at elite than at club level. The athletes will dig pretty deep anyway, and know their own bodies very well. Can the 2-hr barrier be broken? Ed highlights several factors in his book, which, if put in place, could help achieve it, but I think it would need the IAAF to change its rules and allow marathons to be run on a more track-like ergogenic surface, and would need a major backer to get the runners to work together rather than competing. Pacemakers hopping on and off until the finish would help.’

In January 2016 Murray’s next ultrarunning challenge takes him to Outer Mongolia to run over a hundred miles ‘In the Hoofprints of Genghis Khan’. He’ll be running through forests populated by wolves and bears. Should he encounter any, well, that 2-hr barrier could be broken sooner than later.