On August, 15th Martin Rush (England Athletics) gave a presentation to 20 Serpentine members about how to master the transition from a 3h marathon to a 2:45h marathon (women) and from 2:45h to 2:30h (men) and beyond, for those with some good genetic luck. The seminar was attended by a mix of coaches and athletes who were curious to find out from a senior coach what is required to make the transition and what kind of training makes the difference.

About Martin Rush

The talk started with Martin giving a brief background about his vita. His dad was a teacher and as it happened he had an opportunity to teach in Kenya, Nairobi for some time. This happened when Martin was still at the age of 7. A few years later in his teens the Rush family moved back to the Lake district and Martin met an inspiring teacher/coach who encouraged pupils into race walking. It was here were Martin had his first opportunity to take up race walking competition and he quickly excelled at a junior race walker and won the English Schools race walking 1983. Ultimately he found his sport and progressed to qualify and took part in the Barcelona Olympics in 1992. In the same year he broke the British record in the 5km walk. He always combined walking and running as a form of base building. Running-wise he managed to compete at a national club level standard with a best for the 10 mile distance of under of 50 minutes. Professionally, Martin studied sports science and qualified as a teacher. He worked with the Australian Institute of Sport, UK Athletics and now England Athletics in the capacity as national coach mentor. Martin is a UKA Level 4 Endurance coach and is the coach of his wife Holly Rush, a GB international marathon runner with a marathon PB of 2:37.

Setting the Scene

The main theme of the talk was based on marathon progression. To put the theme in context, David Chalfen provided some further information of what is possible at a club level and what members at Serpentine RC can aspire to. When asked at an interview what mileage is required to excel at the 10k Dave reluctantly after many “depends” and “ifs” came up with a number of 50mpw as a minimum average and as a starting point for marathon training. His previous club’s women’s team managed to win a national medal in the London Marathon where 3 athletes had sound runs. The result was achieved with far fewer members in their 20s and 30s and with a basic environment. Considering Serpentine’s setup and opportunities this should be a level any committed long end endurance athlete should aspire towards.

Ferrari vs. Diesel

Are you a Ferrari or a Diesel? Martin asked this question in order to find out what type of runners do we have in the group. The Ferraris are more speed oriented and their shorter distances are in comparison usually faster than their marathon times. Then we have the Diesels. The Diesel goes on forever though does not have a lot of speed, the half marathon or marathon times are usually better in comparison to the 5k/10k. Hugh Jones was an example of a Diesel, a sub 2:10 (2:09:24) runner with ‘only’ a mid 62s half marathon PB while Steve Jones, a strong frame was a more a Ferrari, a 1:00:55 ½ marathon PB and 2:07:13 marathon (he split 61.42 half way!). Martin suggested with better pacing Steve Jones could have run more close to 2:05.

More in detail Martin provide further context in terms if Marathon and XC season can be combined. Martin is a firm believer and preparation and leaving no stone unturned. Ie if it doesn’t work out on the day then often something went wrong in the preparation or the run up to the event. Hence, Martin advocates towards the end of XC season to wind down and focus on the key marathon sessions. Failure to address the switch means peaking at the wrong time or ultimately sub standard performance in the target race.

Next, Martin explained the energy systems and how each of the workout fits into the hierarchy. Endurance athletes obviously need to spend a lot of time running. Martin is a firm believer by just running more or more frequently one automatically improves. However, at some stage the effect of training more wears off, the law of diminishing return kicks in and athletes (or coaches) have to find new ways to train the body. Quite often this next stage is achieved by applying more structure and ultimately more specificity.

If there was one key point of the talk then it was about how both the fat burning system and the sugar system work in tandem with each other. For example, for 3k/5k and 10k the ‘sugar’ system is predominately serving the athlete energy while the fat system is vital for longer distances such as the marathon. Training the fat burning system is about at which rate the body consumes which type of energy as a source. According to Italian Coach Renato Canova this point of optimal split to maximise the fat burning whilst eking out the glycogen is about 3-4% below marathon pace, so spending enough time at this intensity will be most beneficial for the marathon runner.

Energy Systems

Martin covered the fundamental energy systems used in athletics. For short-sprints the ATP system and for long prolonged endurance running the fat burning system. The shorter and intense the running gets the more energy resources are drawn from sugar, while the longer the distance goes and the slower the pace the predominate source for energy is based on fat. As the marathon is 99% an aerobic event then majority of fuel comes from fat and less from sugars. Hence, is vital to teach the body’s ability burn fat most efficiently. Martin made clear that when in marathon training and not spending too much time in the intensive aerobic training zone or potentially by over reaching the body then switches to sugars for energy instead of fat and the training effect is lost. Based on the philosophy of Renato Canova to train the body most efficiently to burn fat is around when the training intensity is 3% slower than Marathon pace.
Marathon-specific block sessions

What else can I do to prepare myself for the physical demands of the marathon? Martin mentioned that a lot of his athletes usually take part in a Tuesday night session covering 5-6m worth of intervals. Usually on the following day a 5k/10k runner would focus on a recovery run. However, a marathon runners can take advantage of the training load/recovery effect to deplete energy stores further by doing an additional harder run in the morning followed by recovery. The training effect will mimic running on a tired state, ie. the later stages of the marathon.

Martin mentioned when one of their athletes (typically working 9/5) couldn’t fit 2 ½ hour long runs in, so instead used block marathon block training. Coaches like Renato Canova make use of marathon-specific blocks in a marathon preparation. For example, a 10km steady run (~85% MPR), followed by a 10km consisting of 1 min hard 1 min easy in the morning, followed by another 10km paced run in the evening. These double days can be extended to cover something very close to the full marathon distance, with considerable amounts done at a similarly strong pace.

Other alternatives mentioned were doing 2x 13.1m on a Sunday, a steady 13.1m run in the morning followed by a harder 13.1m run in the evening. In the last couple of years I came across Phil Sly who usually liked to do the Kingston 16m race in the morning at marathon pace, followed by another 10m in the evening.

Marathon-paced Runs

What is a marathon-paced run? A marathon paced run is a training run to be run at the target marathon pace (MPR). For a 2:45 marathon this pace is 6:18 min/mile and for 2:30 marathon 5:44 min/mile. A half marathon of 77:30 mins and 70 mins provides an indicator how achievable those marathon times are.

The ideal duration for MPR ranges from 60 to 90 minutes. Training runs of that duration at a faster pace (near race effort) will not provide the same physiological stimulus, ie. glycogen/fat burning ratio for the marathon and would likely mean the body draws more energy from glycogen, which means in a marathon the athletes would run sooner out of energy (hitting the wall). For exampe, athletes aiming for a 2:30 marathon need to be able to maintain a 5:44 pace. Training 10 miles at 5:35 pace, means the athletes reaches beyond the point of optimal fat burning intensity.

How to get started with MPRs? Martin proposed to get started with a session of 20x 800m, whereas 800m are broken down into a 400m slightly faster at MPR and the 2nd 400m slighty slower than MPR. Next the aim is to progress the distance of running the same pace, ie. 10x 2k of which 2k are broken down into 1k threshold and 1k steady pace. Next, the intensity will increase and MPR is introduced, 20x 2k, ie. 1k @ MPR + 1k @ Steady pace, then 6x 3k, 3k @ MPR + 1k @ Steady pace to ulimtately, 3x 9k, ie. 8k @ MPR + 1k @ steady pace. This will help the athlete to build up to 24k at MPR.

When to introduce MPRs? Martin advises that the athete needs to be reasonable strong and needs to have completed a base building phase. Typically, when aiming for the London Marathon, MPRs are introduced on a weekly basis starting from February and ideally the athlete should be able to sustain the longer MPRs session a month prior to the target race.
Long runs

Should I do a long run longer than the marathon distance (eg, 30 miles)? A common question for those new to the marathon. Martin’s view was that there are questionable physiological benefits of doing an over-distance training run. It will over-load the body and it will take longer to recover. However, the athlete will gain confidence as a finishing an over distance run can boost the moral and can create a sensation to make the marathon distance short. The risk of overuse injury is always present though and if run too fast the recovery can last many days, days which should be more used for marathon specific session. Martin emphasised rather to focus on the aerobic runs to improve to help to improve the fat burning system. Many elite athletes don’t go beyond 2hrs in their long runs, but rather focus on the marathon paced training runs.


What’s the best way to replenish the energy stores in the last couple of days before the marathon? Over the years a lot has been written about the various carboloading regimes. For example, the Saltin diet requires a depletion phase before the loading phase. The method is based on Bengt Saltin a Swedish professor of physiology and requires a 7 day carboloading protocol. The first 2 to 3 days consist of a depletion phase. The athlete would mainly eat a protein and fat based diet. Then typically on a Wednesday a depletion run is carried out. After the depletion run the second phase, a three day period of carboloading follows. As you can see, the Saltin method requires a lot of time and it not always practical. For example, imagine you are running a marathon abroad and you have to travel through a couple of timezones and have to sit in a cramped airplane. In a depleted state the body’s immune system is weakened and more prone to infection. Considering you have done all the hard training for many weeks the Saltin diet is a risky way for carboloading. Besides the Saltin diet was popular in 70s and is now considered outdated, scientifically there are no significant benefits over other shorter loading protocols.

My advise is to start carboloading on a Thursday afternoon. The main loading activity will be on a Friday. It’s important not to train on a Friday. Any kind of additional physical activity will deplete the glycogen stores again. 60-70% of the nutrition is derived from carbohydrates during this phase. Avoid pizza as only a small % is based on carbohydrates with the rest predominately fat. Good sources of carbohydrates are – raisins, porridge, pasta (no sauce) and rice. Typically a total of 8-10g/kg/body weight should be consumed. For example, a 70kg athlete would have to consume up to 700g carbohydrates. Consuming that amount of carbohydrate in form of pasta can be a big ask. There are products available such as “carboloaders” (High5, Perform, etc.) which allows you to load carbohydrates and leaves you less bloated afterwards. Bear in mind that the loading comes often with a weight gain, as every gram carbohydrates requires 3g of water. Drink plenty on Saturday and increase your salt intake, as salt binds the water, which can help you to stay hydrated for longer.


Martin covered many bases of effective marathon training and provided a clear picture what is required to progress from a 3h marathon to a 2:45 and ultimately proceed to a sub 2:30 marathon. Rome wasn’t built in a day and that also applies to the endurance athlete. What is important though is to bear in mind the bigger picture and building an endurance engine.

Rush M., 2011. Marathon Progressions, Serpentine RC [online] August 16th. Available at[Accessed August 16th]

Arcelli E. and Canova R., 1998. Marathon Training: A Scientific Approach, International Amateur Athletics Federation (IAAF)