question: Why do marathoners rarely run marathon distances in training?
comment: *For most people* - training by running a full marathon is kind of like regularly shooting yourself with a .22 to build up a tolerance to bullets. Its incredibly unhealthy and is so far beyond the limit of what your body can do that it just harms you without meaningfully building endurance. The idea behind marathons is that you run them very occasionally and just accept the harm that they cause because the prestige of running a marathon is what motivates you to regularly run shorter, healthier distances. Even then, people who only occasionally run marathons and train by running shorter distances have a much higher incidence of knee and heart problems than those who do not. As with everything though, there are a few people that are just naturally gifted and can run those distances regularly. But they also typically develop severe knee and heart problems in their 40's or 50's.
passages: The long run is an important element in marathon training. Recreational runners commonly try to reach a maximum of about in their longest weekly run and a total of about a week when training for the marathon, but wide variability exists in practice and in recommendations. More experienced marathoners may run a longer distance during the week. Greater weekly training mileages can offer greater results in terms of distance and endurance, but also carry a greater risk of training injury. Most male elite marathon runners will have weekly mileages of over . It is recommended that those new to running should get a checkup from their doctor, as there are certain warning signs and risk factors that should be evaluated before undertaking any new workout program, especially marathon training.
   Many training programs last a minimum of five or six months, with a gradual increase in the distance run and finally, for recovery, a period of tapering in the one to three weeks preceding the race. For beginners wishing to merely finish a marathon, a minimum of four months of running four days a week is recommended. Many trainers recommend a weekly increase in mileage of no more than 10%. It is also often advised to maintain a consistent running program for six weeks or so before beginning a marathon training program, to allow the body to adapt to the new stresses. The marathon training program itself would suppose variation between hard and easy training, with a periodization of the general plan.
   "Most (marathoners) run in one or two marathons a year," Sayre said. "They'll run once in the spring and once in the fall. They say that it takes you a day for each mile you run to recover. "But it takes me four days to a week to recover. I think part of it has to do with my diet and part has to do with psychology."
   BULLET::::- All courses must have been measured to AIMS standards and full electronic timing must be in place to provide split timing and final results.
   While the endurance aspect of The Marathon suited some athletes more than others, the constant transitioning between the various legs, and negotiating the break, meant that the winner would have to be adept at every aspect of the IronMan sport, and not just as an endurance athlete. 
  
  The typical distances for each leg were:
  
  Run 1200 m
  
  Ski 3200 m
  
  Swim 1600 m
  
  Board 2400 m.
   Running economy (efficiency) can be credited with being an important factor in elite marathon performance as energy expenditure is weakly correlated with a runner's mean velocity increase. A disparity in running economy determined differences in marathon performance and the efficiency of these runners exemplifies the marginal differences in total energy expenditure when running at greater velocities than recreational athletes.
  
  Section::::Physiological characteristics of marathon runners.:Lactate threshold.
   800m runners have training plans that include both speed and endurance work, in order to improve both the aerobic and anaerobic energy systems, as both of these are used in the race. Almost all 800m athletes’ training will be on the track during the outdoor season (Summer), and will mostly consist of repetitions of distances between 200m and 1000m. Coaches have varying opinions on training during Winter; some argue the athlete should continue to do 800m training and racing on indoor tracks, whereas others argue that cross-country running is more beneficial as it develops strength and endurance. 800 metre runners tend to include at least one longer run per week in their training schedule, but this may be more depending on their standard. For junior athletes these may be 2-4 miles (3-6km), however for senior athletes these may be 5-7 miles (8-11km). Sebastian Coe ran around 60-70 (95-110km) miles per week at his peak, whereas Steve Ovett ran 100-120 miles (160-190km). It is worth noting that the training of these two athletes was aimed at the 1500m and mile as well as the 800m. The higher an athlete’s standard, the more likely they are to do “strength and conditioning” training, which may include weight training, circuit training, or plyometrics. 
   While preparing for the race, Bradley suffers a knee injury and is unable to compete. He is clearly upset by this, and takes out his frustration by going for a long bike ride. O'Connor and Caille go through the new experience of the long training sessions necessary for a marathoner. Meyers lends his veteran knowledge while leading slower training runs with his daughter, who is running her first marathon.
   Physiology of marathons
  
  The physiology of marathons are typically associated with high demands on a marathon runner's the cardiovascular system and their locomotor system. The Marathon was conceived centuries ago and as of recent has been gaining popularity among many populations around the world. The, now, 26.2 mile (42.195 km) distance is a physical challenge that entails distinct features of an individual's energy metabolism. In order to understand why marathon runners finish at different times, it is important to understand what physiological characteristics of marathon runners consistently present themselves.
   On 20 March 2018, an indoor Marathon took place in the Armory in New York City. The 200 m track saw a world record in the womens and mens field. Lindsey Scherf (USA) set the indoor womens world record with 2:40:55. Malcom Richards (USA) won in 2:19:01 with a male indoor world record.
  
  Section::::Marathon races.:Wheelchair division.
  
  Many marathons feature a wheelchair division. Typically, those in the wheelchair racing division start their races earlier than their running counterparts.
   Fred Pilon, the publisher of UltraRunning Magazine, estimates that there are 8,000 Americans who run ultra marathons, which is defined as anything above the standard 26.2-mile marathon. That group includes Joe Schlereth of Fresno, Calif., who ran 9,021 miles in 1996 (173.5 miles a week), and the Sri Chinmoy Marathon Team of Jamaica, Queens, which began a 3,100-mile race, around a city block, on June 13 with a 51-day time limit. Most ultrarunners, Pilon said, are hobbyists who average 50–60 miles per week.
  
  Section::::Training Methods.
   BULLET::::- Eliud Kipchoge (Kenya) ran a time of 2:00:25 at the Nike Breaking2 in Monza on 6 May 2017 that was run with the use of fuel and hydration on demand, and in-out pacemakers. Therefore, this attempt is not eligible for official ratification.
  
  BULLET::::- Geoffrey Mutai (Kenya) ran a time of 2:03:02 at the Boston Marathon on 18 April 2011 that was run on an assisted course (in the case of Boston, a point-to-point, net downhill course in excess of the standards) and is therefore ineligible for record purposes per IAAF rule 260.28
   Section::::Physiological characteristics of marathon runners.:Aerobic capacity (VO).:Limitations to aerobic capacity (VO).
  
  During the course of the marathon and endurance exercise in general limitations to one's aerobic capacity are what yield these athletes' aerobic capacity and therefore, their performance in running a marathon.
  
  Section::::Physiological characteristics of marathon runners.:Aerobic capacity (VO).:Limitations to aerobic capacity (VO).:Cardiac.
   Training programs can be found at the websites of Runner's World, Hal Higdon, Jeff Galloway, and the Boston Athletic Association, and in numerous other published sources, including the websites of specific marathons.
  
  The last long training run might be undertaken up to two weeks prior to the event. Many marathon runners also "carbo-load" (increase carbohydrate intake while holding total caloric intake constant) during the week before the marathon to allow their bodies to store more glycogen.
  
  Section::::Running.:Glycogen and "the wall".
   BULLET::::- Moses Mosop (Kenya) ran a time of 2:03:06 at the Boston Marathon on 18 April 2011 that was run on an assisted course and is therefore ineligible for record purposes per IAAF rule 260.28
  
  BULLET::::- Marius Kipserem (Kenya) ran a time of 2:04:04 at the Abu Dhabi Marathon on 7 December 2018 that wasn't recognized by IAAF
  
  BULLET::::- Abraham Kiptum (Kenya) ran a time of 2:04:16 at the Abu Dhabi Marathon on 7 December 2018 that wasn't recognized by IAAF
  
  BULLET::::- Eliud Kipchoge also ran 2:02:37 (2019), 2:03:05 (2016), 2:03:32 (2017), 2:04:00 (2015), 2:04:05 (2013), 2:04:11 (2014), 2:04:17 (2018).
   With the growth in popularity of marathon-running, many marathons across the United States and the world have been filling to capacity faster than ever before. When the Boston Marathon opened up registration for its 2011 running, the field capacity was filled within eight hours.
  
  Section::::Running.:Training.
   BULLET::::- "The Marathoners" (1980) G.P. Putnam's Sons,
  
  BULLET::::- "Beginners Running Guide" (1987) Anderson World; Revised edition,
  
  BULLET::::- "Run Fast: How to Train for a 5-K or 10-K Race" (1992), Rodale,
  
  BULLET::::- "Marathon: The Ultimate Guide" (1993), Rodale,
  
  BULLET::::- "Johnny Rutherford (1994), X-S Books, Inc.,
  
  BULLET::::- "On the Run from Dogs and People" (1995), Roadrunner Pr; 3RD edition,
  
  BULLET::::- "Hal Higdon's How to Train: The Best Programs, Workouts, And Schedules For Runners Of All Ages " (1997) Rodale,
  
  BULLET::::- "Marathon: The Ultimate Training Guide" (1999),
   2017 2 minutes, 9 seconds
  
  2016 2 minutes, 28 seconds
  
  2015 1 minute, 2 seconds
  
  2014 1 minute, 38 seconds (this is 6 mins, 25 seconds faster than the 2012 cutoff since qualifying time was 5 minutes slower before 2013, and 2014 included 1,649 time qualifiers given guaranteed entry since they were unable to finish in 2013 due to the bombing, so would have been even faster if they had participated in the Sept open registration) 
  
  2013 0 minutes (however, this is the first year that qualifying times were 5 mins faster than in 2012) 
   The interaction between different energy systems captures the essence of why certain physiological characteristics of marathon runners exist. The differing efficiency of certain physiological features in marathon runners evidence the variety of finishing times among elite marathon runners that share similarities in many physiological characteristics. Aside from large aerobic capacities and other biochemical mechanisms, external factors such as the environment and proper nourishment of a marathon runner can further the insight as to why marathon performance is variable despite ideal physiological characteristics obtained by a runner.
  
  Section::::Brief history of marathon running.
   Beginning with the registration for the 2012 Boston Marathon, a cutoff beneath the qualifying times was instituted. The cutoff time is given in minutes and seconds and is subtracted from the age group qualifying times to determine who will be allowed entry and who will not. For example, for the 2012 marathon, when registration closed and the 1:14 cutoff was announced, a runner who "qualified" with a time faster than 3:10:00, actually needed a time of 3:08:46 to earn entry into the marathon.
  
  History of cutoffs:
  
  2019 4 minutes 52 seconds
  
  2018 3 minutes 23 seconds
   As in all open water swimming, tides, surface currents and wind-chop are major determinants of finish-times. For a given course, these factors can vary dramatically from day to day, making any attempt to draw conclusions about athletic ability by comparing finish times from performances undertaken on different days meaningless.
   According to a Canadian study presented in 2010, running a marathon can temporarily result in decreased function of more than half the muscle segments in the heart's main pumping chamber, but neighboring segments are generally able to compensate. Full recovery is reached within three months. The fitter the runner, the less the effect. The runners with decreased left ventricle function had an average peak weekly training distance of , while those who did not averaged . The marathon was held in weather. According to one of the researchers: "Regular exercise reduces cardiovascular risk by a factor of two or three in the long run, but while we're doing vigorous exercise such as marathon running, our cardiac risk increases by seven."
   The youngest under 4 hours is Mary Etta Boitano at age 7 years, 284 days; under 3 hours Julie Mullin at 10 years 180 days; and under 2:50 Carrie Garritson at 11 years 116 days.
  
  Section::::Statistics.:Participation.
  
  In 2016, Running USA estimated that there were approximately 507,600 marathon finishers in the United States, while other sources reported greater than 550,000 finishers. The chart below from Running USA provides the estimated U.S. Marathon Finisher totals going back to 1976.
   List of marathon races in North America
  
  The following is a list of marathon races in North America.
  
  Section::::Legend.
  
  The criteria for whether a marathon receives an IAAF Label designation are based on six general issues: race organisation, course timing and measurement, media services, quality of international field of runners, health and safety, and athlete equality.
   BULLET::::- The race must be organised in accordance with IAAF Competition Rules, the standards of the national athletics body, and must comply with all relevant local and national laws. The race must be organised in a way that minimizes ecological damage to the surrounding areas.
  
  BULLET::::- All courses must have been measured to AIMS standards and full electronic timing must be in place to provide split timing and final results.
  
presuppositions: Running a marathon distance is beneficial to training. Running marathons would be effective training for marathon runners. 
corrections: Running marathons to train is incredibly unhealthy and causes harm without meaningfully building endurance. Running marathons to train is incredibly unhealthy and harms you without meaningfully building endurance.
raw_presuppositions: Running a marathon distance is beneficial to training. Running marathons would be effective training for marathon runners.  Marathon runners should train by running marathons.
raw_corrections: Running marathons to train is incredibly unhealthy and causes harm without meaningfully building endurance. Running marathons to train is incredibly unhealthy and harms you without meaningfully building endurance. Running marathons to train is incredibly unhealthy and harms you without meaningfully building endurance.