Asics nutrition webchat with Ruth McKean

RUTH MCKEAN

Stephen McCarron wrote (see)

I'm keen to understand how glycogen requirements vary by runner and by training.

Is it the case that if you train yourself to burn fat efficiently (e.g. by doing long runs in a glycogen depleted state), then your glycogen stores won't deplete as fast?

Whenever i read about how much energy you're required to take on in a marathon it takes a one size fits all approach (e.g. x grams of carb /y kg of body weight).  But surely the requirements should vary depending on fast/slow you burn through your glycogen? 

 

Hi Stephen.

I posted the following on a recent thread as we were discussing whether carb loading was worth doing so I thought this could be useful for you so you can see want factors may affect performance during a marathon and hoping this might help explain why carb loading is possibly helpful for some runners. Carb loading is about helping you maintain pace in the latter part of a marathon (say 20miles onwards), it can’t make you run faster but it could actually be a big part of the puzzle for you. Although ensuring you are aiming for 30-60g of carb per hour during the race as well could be also key if it is a nutritional problem.  

Marathon studies suggest that around 40% of runners hit the wall and those most likely to hit the wall include runners that don’t do the miles in training (running 20miles or less on training runs), lack of fuel (carbohydrates) & the expectation that you are going to hit the wall (most common at mile 21 or 33km). Taper will also likely play a part. This expectation  point is an interesting one because it is not uncommon to see endurance runners cross the finish line then collapse ... suggesting their mind can make them get to the finish line before it gives up. Therefore having a plan for your mind when the going gets tough is an aspect of marathon training not to be overlooked.

That leaves the fuelling issue which is commonly talked about in marathon running: that running low in carbohydrates will make you slow down as your legs feel like they have turned too led!  Unlike our large fat stores (the leanest of runners will have enough energy from fat to run back to back marathons) our carbohydrate stores are relatively very small. You often hear that if carbohydrate stores are fully stocked they will last for around  90mins however this is quite a simplistic view as each runner runs 26.2 miles at different speeds and if you run it faster you will use your carb stores up more quickly but as a guideline most people will use similar overall energy....running 26.2 miles faster requires more power but proportionally less time so if running it slower you still require the same energy overall but the slower runners may be able to use more fat and less carbs so the proportion/mixture of fat/carb use is different.  However, running at a constant speed or maintain constant effort (when hills come into a race) is probably the most efficient way (metabolically/fuel) to race so pacing strategy is also crucial.

When your muscles are working they use a mixture of fat & carbohydrate, you will never use 100% carbs or 100% fat (protein accounts also for a small amount) but carbohydrate account for a greater proportion as intensity/speed increases while fat accounts for a greater proportion at lower intensities. You cannot release enough fat to use quickly enough at the higher intensities/speed during exercise, this why carbs become important for energy at higher pacing. Therefore the total carbohydrate use over the course of a marathon depends not only on the distance run but

RUTH MCKEAN

continued from above...

Therefore the total carbohydrate use over the course of a marathon depends not only on the distance run but also the intensity it is run.

However the total amount of carbohydrates available to a runner will not only depend on how loaded they have manage to get their running muscles before a marathon (and this I will help with!) but also how big your liver is (physiology I can’t alter!) and also body mass/muscle mass (if you have a lot more weight to carry over the distance then your working muscle need to work harder to carry your body mass and hence use more energy). If very lean with large relative leg muscles this will cost less energy to transport, this is why most elite runners have good running economy & why body composition is important in endurance running.  Often I look to cut down on weight particularly in the runners wanting faster times/beat their PB... providing the fat is there is lose!

In summary: Runners with large aerobic capacity/VO2 max (large engine!) and large leg muscles (relative to their size and can store more carbs in these than you or I) & can often store enough liver and muscle glycogen (carbohydrates) to run a marathon without hitting the wall and the need to take on little carbs during the race (some elites none) however this usually applies to those running sub 2.15.!!! Runners with smaller VO2  max and smaller leg muscles relatively to size will run at a slower pace but will need to refuel (as don’t have big enough stores & running economy not as good ) and often  benefit from loading muscles in the days leading up to a race.

So the need to carb load is not universal as it depends on muscle mass, liver and muscle stores but for those more normal people with a smaller horsepower engine then carb loading can help by allowing you to run at a given speed for longer and  why I suggest carb loading (usually only for 2 days but for some very well trained club runners I perhaps one day is required!) and some mid-race fuelling.

If want to train to use fat more efficiently then it is training you do this in not a race situation.

I hope this helps shed some light!

RUTH MCKEAN

Hi Orapidrun

I hope the post to Karen and Stephen helps explain why carb loading can be useful and what this looks like.

The thing about carb loading is that even if you only manage it for one full day before a race it may still be very useful so perhaps instead of doing it for 2-3 days why don’t you aim for only one and see if this helps?  but split meals over 6-8 sittings and try and use at least a litre of full sugar cordial over the day (as this is 100g of carbs!).

Start with aiming for 8grams of carbs per kilogram of your body weight but only up to a max of 800g.So if you weight 70kg then aim for around 560g of carbohydrate split up over the day.

If need to have less before bed to help reduce feeling of being full then need to fit more into other parts of the day but exclude all non-carb foods for the day – protein, fatty foods etc.

And make sure you are aiming for at least 30-60-g of carbs per hour during the race and try starting taking fuel on board form 45minutes into the race ad then every 30-45 after.

Once you sorted the problem you can then personalised the amount of carbs you need in a race but start with the above guideline form the first hour until you getting an eating strategy that appears to work for you. It is hard to give very general advice but the above may well be a good start point for you.

Best of luck

Ruth

RUTH MCKEAN

Minni wrote (see)

Hi Ruth,

I have seen a new range of sports nutrition focused on energy and recovery products for the over 35s.  

Do the over 35s need something different to the *ahem* younger athlete?  And if so does this continue to change as one gets older?

 Hi  Minni

Hope all good with you today?

To me it is another marketing package, they have added a couple of extra B vitamins etc and making it sound like you need these to maintain muscle mass. No different to other products out there marketing to all ages of athletes really. Much older people may need slightly different things but again can get from diet! I don't buy into it at all!

Ruth

 

RUTH MCKEAN

Debby Mullier wrote (see)

Hi

Could you suggest how to eat in the week before to avoid the runner's trots during the race, while ensuring you can 'go' before it so you're comfortable at the start?  If that could encompass carb-loading and how to avoid feeling heavy-legged at the start that would be fab!

 

Debby

I hope the previous posts can help?  

RUTH MCKEAN

Darren Hann wrote (see)

Hi Ruth, I'm running London in April and this will be my first marathon. Any advice on what to take in the final 3rd of the race to give me that extra energy I'll need to get me to that finish line. Thanks. Darren

Darren

First marathon – fantastic! I really hope you enjoy the whole experience!

Some of my previous posts are worth reading I think as the problems with the final 3rd is that it is often what you have done in training and in the lead up to the race (how you eat in the 1-2 days before) that will dictate how this aspect goes. If you get your pacing wrong in the first half of the race you will pay for it in the second half and you can do little to get your legs back if this happens! so pacing is so important and doing sufficient long runs in training as if you have not done the miles in training you can expect to suddenly expect this to happen in a race with no issues.

I also suggest you eat more carbs in the days leading up to the race (aim for 2 days of adjusting carb intake) and have good high carb breakfast (see above posts) and then aim for 40-50g of carbs per hour in the race (most gels have around 20-25g) so if plan to use these perhaps one every 30minutes but you must practice this in your longest couple of runs (18-20mile training runs) to see how this goes for you.

If able to take gels; may be worth a high caffeine gel (75mg) at around the 20-22mile mark to give that extra kick!

I strongly recommend that you plan what you are going to eat the day before, race morning and during the race as you have put hours of training in and something as simple as nutrition can spoil it all.

As it is your first you will learn lots of things but the key to nutrition is to listen to the basic guidelines and start with these but then taper to suit as you become more experience marathon runner. Nutrition is very personal and what works for one person often will not work for the next but the initial nutritional guidelines can be the perfect place to start!

 

RUTH MCKEAN

seren nos wrote (see)

Right......

I'm doing a multiday event which will see me doing an ironman a day every day for several days.....

 

what foods do you think would be the best to keep the energy levels up to keep going for around 18 hours a day for continuous days...

High fat, the aim will be to not lose too much weight too quickly so gels etc will not suffice. You are looking at some foods which nutritionist would not usually recommend- instance mashed potatoes, chocolate bars, malt loaf meal replacement drinks such as complan or build up (high street chemists). The aim is to find a range of foods which you can stomach. Often people like chicken noodle soup as a drink due to the salt flavour but do not use the strategies for a  marathon as a couple of gels an hour won't cut it!  I often advise a box of different foods so when you get to get point you can fill a bag with different things depending on what you feel like. Eat every hour and every few hours have something more substantial such as mashed potatoes, soup and bread then chocolate bars etc in between. But also have some banana in there as well ; a real mix of savour and sweet. Very general but hope it helps!

RUTH MCKEAN

actimel wrote (see)

Hi Ruth, I have two related questions that I hope you might be able to answer. There's a lot of talk during marathon season about getting lean and reaching your ideal racing weight but I wondered whether there was any guidance on minimum BMI or how to know whether you've gone below an 'ideal'?

I'm 5ft and currently weigh 6 and half stone. Last year, I started to feel unwell when I dipped below this weight in marathon training although I was diagnosed with iron-deficiency anaemia at the same time. I've since been diagnosed with a vitamin B12 deficiency and still take supplements for both deficiencies as I eat very little meat (particularly red meat as it triggers IBS symptoms).

I'm starting to feel drained again but find it hard to tell whether it's due to weight or dietary deficiencies. I'd be interested in any tips for topping up on iron and B12 without eating red meat.

Many thanks!

Thanks for your post. You are very very underweight (BMI of 17) and this will be why you feel so drained and have some of your nutritional deficiencies.  I am surprised you have not been referred, if already being seen by a doctor, to someone that can help you to gain weight. You may need to gain a stone before you will feel less drained. I would speak with your doctor as to be this underweight  and training for a marathon is only going to lead to possible long term bone injuries and further energy & health problems. Please ask your doctor for a referral to a dietitian.

Ruth  

 

RUTH MCKEAN

Lucy Kilby wrote (see)

I'm running Edinburgh in may- my first marathon! What is best to eat before or after long runs? Also all the training plans seems to head up to around 20 miles we started earlier and were going to train slightly higher to 23-24 miles is this wise to do so if u have the time? Thanks

Hi Lucy

Good for you!

The best thing to eat before long runs is things like bread/toast and jam/honey/banana, breakfast cereals, beans on toast, pasta and tomato based sauce. Basically high carb, low fat foods . Practice timing of when you can have these before you run but for many it is around the 2 hour mark or if  can not manage that then aim for  3-4hours before then a light snack 60-90minutes before you run such as 1/2 a jam sandwich or banana etc .

After long runs - you should have a high  food and a high protein food (ideally a dairy protein such as milk, yoghurt etc  but if don't like dairy foods then soya based food could replace this). So great recovery foods are: cereal & milk, 500ml of milkshake (high in carbs and protein), scrambled eggs on toast with a yoghurt  and fruit, cottage cheese sandwich and fruit. Then eat a further meal/snack in another couple of hours. This should help you recover from long runs.

To be honest the 20mile mark query is a coaching question and although I think I know the answer I am not a 100% sure so perhaps best not to answer!

RUTH MCKEAN

Duracell Bunny2 wrote (see)

I find Morton neuromas in my foot limit my training. Do you have any nutrition tips to help?

Hi Duracell

I do not know what Morton neuromas.

RUTH MCKEAN

I have totally run out  of time but I will come back on later and answer the last of the questions - sorry!

Annie RW

Thanks for all your questions and thank you to Ruth for joining us. 

We'll be posting the highlights as an article page.

marrows

Ruth - thank you so much for taking the time to give such a helpful response!

[Deleted User]

HI Ruth - probably too late ..... but was wondering if it is naive of me to not use gels and have homemade flapjacks during a marathon as my fuelling?

thanks!

RUTH MCKEAN

MissH

Yes, you could.  If wanting to aim for your potential/fast time may not work as would take a long time to digest and when running at a higher intensity blood is diverted away from your digesting system to go to working muscles so may cause problems but  if running a slower race and you can stomach these then go for it!

RUTH MCKEAN

Roundman wrote (see)

Hi Ruth - I will be running Paris in April and this will be my 5th marathon.  Regardless of how I have fared in each of my previous races I seize up with cramp every time at the end in both legs and it is pure agony. My father used to run marathons and suffered in a similar way. Is there anything I should be adding to my diet that will help here? I am fine after long training runs (18-22m) and always ensure I am well hydrated and take gels during races. Thanks

Roundman

It may be worth reading the other post on cramps as well to get a little more background.

I wonder if it is to do with running style - such as more on your toes and when you stop this may be partly why you cramp. The reason it happens at the end is because your muscle are so tired and when you stop your muscles involuntary contact . I wondered if you put some efforts in at  end of a long run if this would get your muscles used to this? The only thing may be worth trying from a nutritional view point is to add a high electrolyte tablet  (high five do high sodium tablets)to a drink but then you need to carry a bladder to carry  fluid?   I do not have a definite nutritional answer as I think it is a conditioning of your muscles when they are really tired  or perhaps your running style makes this more likely to occur but adding some sodium may help but until you try it I could not be sure. Perhaps even lightly salt your food the night before but again I am not actually sure this will help but worth trying.

RUTH MCKEAN

MACb wrote (see)

I am reading a book called "Mastering the Marathon: Time-Efficient Training Secrets for the 40-Plus Athlete", and the author seems to be taking quite a few gels and energy drinks the morning before his marathons. I kind of thought that the gels were for use during the race to help you at the end. he also has what sounds like a standard pre race breakfast. So isn't this kind of over loading on carbs? 

 

Thanks for post and delay in getting back to you. I do think it is over loading on carbs , it is almost suggests trying to carb load the morning of a race. If you read over my posts today I suggest carb load in 1-3 days before then some cereal/toast 3-4 hours before then a further snack 90-60minutes before but this can be a banana, 1 piece of bread and honey or if want to move this snack nearer to race start then a gel or sipping on a sports drink but you are correct they are not necessary before  race, normal food is suffice but often people use gels as easy to carry to race start and easy to digest but many people also take a banana an hour before the start. The only time I think gels are really useful are on runs longer than 2 hours (for most people)  and in on these runs you practise using them for races but jelly sweets do the same job as the gels.  

RUTH MCKEAN

david yeabsley wrote (see)

Hi Ruth. Could you give any tips for a first marathoner, aged 49, and diabetic please? I have been educating myself. I am an experienced runner and have so far ran up to 18 miles...

david

This is a tricky question as I would like to have known more about our diabetes and how long you have had this for and what meds you use- base - bolus or tablets, do you carb count etc

However, some basis tips may be:

• High blood sugars are a risk so you will need to reduce your insulin dosage, timing and injection – you may need to speak to your diabetes. As a regular runner you may already be good at this.
• Know the sign of a hypo – early on and make sure you act on first signs – always carry food even on recovery runs especially in the high mileage weeks where your body could react differently.  
•  Track the type of training with corresponding insulin dosages as will help you track what happens when you do an intervals session, a long run etc  but also how do your blood sugars response to injury and sickness.
• If blood sugars above 14mmol/l (especially if ketones are in urine) do not exercise until you have better control. If you exercise with high levels of blood glucose this will disrupt normal metabolic responses and will elevate these levels even further which can be damaging.
• The recommended diet for a runner with or without diabetes is the same so I would encourage you to adjust your insulin or other meds to the response of exercise rather than distorting food intake to suit insulin or other medications. As with all runners try and spread food intake out over the day.
• You need more than others to make sure you consume carbs during your long runs and I would advise against carb loading unless you really are a well-controlled diabetes and now how to alter insulin for this. You should still be aiming for around 50-60g of carbs per hour in the marathon but you may need more towards the latter part of the race.
• Have you tried injecting before running in different sites? High sugars may occur if your normal insulin dose includes short acting (if injected a few hours before exercise) which then reaches its peak action during the exercise. This effect may be exaggerated if the previously injected limb is exercised promoting increase insulin absorption from the injection site. Therefore perhaps abdominal site is best ?

 

• If you cannot work out why your blood glucose reading is what it is then you may need to see what is happening throughout the night especially after a long run/hard prolonged session as you will increase your insulin sensitively for up 12-15 hours .Therefore if you have “problem” readings after certain runs you may need to consider getting up at night and finding out what is going on over the 24 hour period to help solve the problem – do you need to adjust background insulin  at morning or night ? are you having a rebound high etc but it may help see a fuller picture.  

Not sure how helpful this is as I do not know what problems you may be having but basically you should be going out for a run with a normal bold sugar and aiming to maintain this. The problem may be how your body reacts after the run.

All advice about optimal recovery and all nutrition is no different  for a diabetic but what you need to do is adjust medication so that you can eat as you need to train!

Good luck in your first marathon and the I hope you can embrace the extra challenge that diabetes may bring - you

RUTH MCKEAN

Thanks for all your questions ! Good luck to you all in your races this year.

Minni

Hi Ruth!  Yes thankfully things are much better for me now I've got that horrible bug out the way!!    I had the same feeling about the 'over 35' nutrition but nice to get your opinion.

Thank you for your answers to all these questions - there is so much good stuff here.  You have really helped me understand a lot about marathon fuelling over the past couple of years.  I will definitely be following your carb loading advice again.

 

RUTH MCKEAN

Thanks Minni

MACb

Thanks Ruth, that was kind of what I was thinking, it is also what I did for my one and only marathon. So i'll strick to that and not take a load of gels pre-race then!

[Deleted User]

Ruth thank you so much for your reply, it was also very interesting reading all the other insights too.  You more than answered my question and I feel quite confident in my fueling strategy now.  Will be practising it over the next 8 weeks 

John Jenkins 8

Hello, Started running last year and have moved from 100m (yes 100m) to doing 10km races (hope to get 54 mins in Manchester 10km this year) and have registered for the GNR (already done 18km in training) and then on to the Manchester Marathon in April 2015.

I have enough time to train and have a lot of help on here regarding my training plan.

What I am totally clueless on is nutrition.

I am 44 yrs old, height of 5'5" and weight 12 stone.

I want to make sure I start eating correctly for the Marathon and there is no time like the present.

Currently I eat a lot of Uncle Bens rice with Tuna or Chicken, with a co-op pasta dish at lunch with some sushi. breakfast I have Bran Flakes and a coffee. I drink a fair amount of water.

Can you please point me in the direction of food plan as I simple don't understand all the good fat/bad fat, good sugar/bad sugar etc etc. I really am a total novice in this area, but know I need to get on top of it to aid my training.

Thanks in advance.