The five big debates of the past 10 years

The past decade has seen a continued growth of distance running as a mass participation sport.   The major city marathons continue to attract many thousands of entrants with aspirations ranging from sub 2:30 to simply completing the distance in whatever time it takes.  Perhaps more dramatically, parkrun has grown from a local weekly gathering of a few club runners in south-west London to an event that attracts many tens of thousands of individuals at hundreds of local parks, not only in the UK but world-wide, on Saturday mornings to run 5Km in times ranging from 15 min to 45 min before getting on with their usual weekend activities. Over this same period, the ubiquity of internet communication has allowed the exchange of ideas about running in a manner unimaginable in the days when distance running was a minority sport pursued by small numbers of wiry, tough-minded individuals whose main access to training lore was word- of-mouth communication.

Not surprisingly, within this hugely expanded and diverse but inter-connected community there have been lively debates about many aspects of running, with diverse gurus proposing answers to the challenges of avoiding injury and getting fit enough to achieve one’s goals.   Pendulums have swung wildly between extremes.  My impression is that the fire in most of the debates has lost much of its heat as the claims of gurus have been scrutinised in the light of evidence.   However, definitive answers have remained elusive.   What have we learned that us useful from this turbulent ten years?

There have been 5 major topics of debate:

1) Does running style matter and if so, is there a style that minimises risk of injury while maximising efficiency?

2) Are minimalist running shoes preferable to the heavily engineered shoes promoted by the major companies?

3) What is the optimal balance between high volume and high intensity training in producing fitness for distance running?

4) Is a paleo-diet preferable to a high carbohydrate diet?

5) Does a large amount of distance running actually damage health, and in particular, does it increase the risk of heart disease.

In all five topics, debate still simmers.  I have scrutinised the scientific evidence related to all five of these question in my blog over the past seven years, and I hope I will still be examining interesting fresh evidence for many years to come.   However whatever answers might emerge from future science, in our quest to determine the answers that will help us reach out running goals we are each an experiment of one and now is the point in time when we must act. I think that the evidence that has emerged in the past decade has allowed me to make better-informed choices in all five of these areas of debate than would have been possible ten years ago.   In my next few posts, I will summarise what I consider to be the clear conclusions for the past decade of debate, what issue remain uncertain, and what decisions I have made with regard to my own training and racing.

For me personally, the greatest challenge as I approach my eighth decade is minimising the rate of inexorable deterioration of muscle power, cardiac output and neuro-muscular coordination that age brings.  Therefore my approach to these debates is coloured by the added complications of aging.  Nonetheless, my goal is not only to continue to run for as many  years as possible, but also to perform at the highest level my aging body will allow during these years.  I hope that the conclusions I have reached will be of interest to any runner aiming in to achieve their best possible performance, whatever their age.

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4 Responses to “The five big debates of the past 10 years”

  1. Robert Osfield Says:

    That’s quite a range of topics to cover, I look forward to you perspective on the various topics.

    I’m now building up my mileage in prep for my ultra-marathons this year and in particular am trying to balance catabolic effects of elevated cortisol associated with high mileage. One are I’ve just started experimenting with it supplementing with MTC oil and BCAA. I’m curious for your thoughts on how well this might work.

    My thought is that MCT oil will be metablozied into a keytones by the liver and this in turn will lower my rate of burning glucose in my brain and other organs. My hope is that this will sparing will lower the Cortisol levels required to maintain blood sugar.

    With the BCAA’s, studies look to suggest that can help with the muscle metabolism and mitigate the muscle breakdown that occurs as Cortisol levels rise, and after exercise help with building muscles.

    My hope is that I’ll be able to build muscle strength and resilience and lower the risk of over training and injury. I have only just started supplement before and after runs so can not comment on whether this tweak to my diet will make any difference.

  2. canute1 Says:

    Robert, thanks for your comment.

    The proposal that medium chain triglycerides will promote optimal utilization of fatty acids makes sense. However, as far as I aware, the evidence for improved endurance performance from MCTs is slight. Nonetheless very demanding ultras such as the WHWR do make high demands on metabolism and it is plausible that enhancing the ability to utilise ketones to provide energy for the brain is worthwhile. So I think experimenting with MCT oil is probably worthwhile.

    With regard to BCAAs, there is substantial oxidation of BCAAs during endurance exercise and it is plausible that ingestion of addition BCAAs will produce a worthwhile decrease in muscle breakdown. BCAA also provide the amine groups necessary for the synthesis of glutamine from alpha-ketoglutarate. Glutamine is the most abundant amino acid in the body and plays a crucial role in metabolism in gut and in immune cells. Glutamine is mainly produced in muscle cells. Levels fall appreciably after prolonged exercise. It therefore seems to me that ensuring adequate supply of BCAA might slow the potentially harmful decrease in glutamine levels.

    On the other hand, promoting the utilization of alpha-ketoglutarate to produce glutamine will tend to deplete the pool of Krebs cycle intermediates that play a crucial role in metabolism of fats and glucose. However pyruvate can be used to top up the pool of Kreb’s cycle intermediates, so provided enough pyruvate is produced by glycolysis, it is likely to be more important to slow the rate of depletion of glutamine levels than to minimise conversion of alpha ketoglutarate to glutamine. However the complexity of the interactions between metabolic pathways should remind us that the consequences of adjusting a particular metabolite are likely to depend on various circumstances.)

  3. Ewen Says:

    Interesting topics Canute — for myself, particularly 2, 3 and 4. I’m never going to run enough distance to damage my health. I should add that style is important, especially after experiencing a cured hamstring injury after tweaking my form in small ways.

    • canute1 Says:

      Ewen

      I was impressed by the Douglas Wisoff’s video on high hamstring pain to which you provided the link on your blog. It illustrated the fact that even when one can identify a single problem – in that case, over-reliance on the hamstrings for pulling the pelvis forwards – it can arise from any one of several quite different problems in form, ranging from leaning too far back or too far forward, to reaching out with the swing leg. I am pleased to hear that you sorted out the cause of your hamstring niggle.
      As for the risk of cardiac damage, the evidence indicates that multi-marathon runners are at greatest risk, though my speculation is that the specific thing that does the damage is failing to allow adequate recovery after a very strenuous effort, rather than the total volume of running.

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