The Science Behind "Carb Loading"

So, the big day is nearly here. You have trained for months and months and you can finally see a light at the end of the tunnel. But your final week is a very important one as you don’t want to ruin all the hard work leading up to the event.

If you’ve done your research, you will know that there are many things that can go wrong on race day. You could eat the wrong food and have an upset stomach. You could run out of stored glycogen and therefore run out of energy early on in your run. Or you could simply be dehydrated before you even begin the marathon. So, it’s no wonder that the preparation leading up to the marathon is just as important as the training itself.

One of the most common hurdles a marathon runner will face is hitting a wall during the race. The biggest cause of this is muscle glycogen depletion. Glycogen is a fuel derived from carbohydrates and is stored in the muscles and liver, before it is released into the bloodstream in the form or glucose.

The body will usually have enough glycogen to run for about 90 minutes. In order to reserve that much needed glycogen, experts suggest reducing the length and intensity of your runs in the week leading up to your race. This will enable your body to store the glycogen which would normally be used to fuel your longer runs. They also suggest pacing yourself throughout the marathon in order to burn through stored glycogen more slowly.

As mentioned above, glycogen is fuel derived from carbohydrates, hence why there is good reason to “carb load” about three to four days prior to the marathon. A high carb diet generally consists of 7-12g of carbs per kilo of body weight. During this period, try to avoid high fibre foods, gas producing foods and spicy foods as this may cause you to suffer from an upset stomach on race day.

During your “carb loading” period, you should expect to gain roughly 2 kilos due to the extra muscle glycogen and water in the system. Think of it as the extra “fuel” your body will be carrying to help you complete those gruelling 42.2 kilometres. But don’t worry, your normal weight will resume once the marathon is over.

Of course, while increasing your carbohydrate intake, it is best to avoid the high fat foods such as chips, pastries, donuts and the like and concentrate on white rice, pasta with a tomato sauce, oats and english muffins just to name a few. Experts also suggest, as with any dietary changes, that you try out the “carb loading” method prior to the actual marathon.

Protein intake should be between 1.2-1.8g per kilo per day. For example, a 70kg athlete would need to eat between 84-126g of protein per day. Protein is essential for not only muscle repair and recovery, but when combined with carbohydrates, it can help improve protein balance and absorption.

So what does a high carbohydrate diet look like? The following diet is an example provided by the Australian Sports Commission (http://www.ausport.gov.au/ais/nutrition/factsheets/competition_and_training/carbohydrate_loading) and is suitable for a 70kg athlete:

 

Breakfast	3 cups of low-fibre breakfast cereal with 11/2 cups of reduced fat milk 1 medium banana 250ml orange juice
Snack	toasted muffin with honey 500ml sports drink
Lunch	2 sandwiches (4 slices of bread) with filling as desired 200g tub of low-fat fruit yoghurt 375ml can of soft drink
Snack	banana smoothie made with low-fat milk, banana and honey cereal bar
Dinner	1 cup of pasta sauce with 2 cups of cooked pasta 3 slices of garlic bread 2 glasses of cordial
Late Snack	toasted muffin and jam 500ml sports drink*

This sample plan provides ~ 14,800 kJ, 630 g carbohydrate, 125 g protein and 60 g fat.

It is also important to eat a meal at least two hours prior to a marathon to allow the food to be digested. If nerves are a problem for you, try having a liquid breakfast like a smoothie if that is easier to stomach. You will need the energy from this meal to help with your glycogen levels.

Hydration is also key in the lead up to the marathon. Be sure to drink plenty of water during the days prior to the race to ensure you start out hydrated. A pee test is the best way to measure this. If your pee isn’t a light straw colour, then you need to drink more until it is. Dehydration places a huge strain on the body and can significantly affect your running performance. Make sure you start drinking water or sports drinks* early on in the race to minimise the risk of dehydration.

Sports drinks* are a great way to replace lost electrolytes. Sweat consists of three electrolytes; sodium, chloride and potassium, with sodium having the greatest concentrate. Therefore you may benefit from extra sodium. Be sure to practise your hydration strategy prior to the marathon.

After completing the marathon, it is equally as important to refuel, repair and rehydrate your body. After a long run, you have a window of approximately 30 mins when your body is primed to replenish its carbohydrate stores and soak up muscle-repairing protein. A glass of milk, a protein shake* or a smoothie provides a good mix of protein and carbs. Drinking plenty of fluids is also important to replace the water and electrolytes lost through sweat.

So to sum up, ensure you have a nutrition plan, a hydration plan and a “carb loading” plan in place and tested before the marathon so you know exactly what to expect. You don’t want to be dealing with any nasty surprises on the morning of the marathon. Be sure to have a meal at least two hours prior to the run and don’t forget to refuel, repair and replenish post marathon.

 

Author: Hayley Polsen

 

*for information relating to a range of protein shakes and electrolyte drinks specifically designed for athletes, please contact the author of this article hayleypolsen@gmail.com

A Story of Courage, Strength & Determination

In March 2009, Trent Northover was a Canberra raised 23 year old living in London and working as a contractor on a large North East England project. It was a GFC ravaged London where jobs were impossible to get and almost as hard to retain. So when a sub contractor is happy with your work and as a show of appreciation offers the chance to join him and his son running the New York Marathon, it merits consideration, if only for business reasons.  

The former representative Australian Rules footballer who maintained a level of fitness in London by going to the gym had never once contemplated running a marathon. He considered the offer during a night out and in a haze of Lager induced heroics, accepted and so his story begins.

Trent worked in an environment that demanded long high pressure working hours compounded by an expectation, if not requirement to socialise most nights, something he did willingly and well. “I guarantee I was out Tuesday through to Saturday every week”.

Trent purchased a training program and largely followed it even if as he put it, “a 20 kilometre training run might have been preceded by a night out, two hours sleep and a coffee.”

In the meantime, his friend and colleague Jordan Griffith decided to come along and run the race too giving Trent a training partner.

I asked Trent to rate his preparation out of 10 and he gave himself a 6 or 7. “I was certainly committed and downloaded the programs. It was just burning the candle at both ends.

“I entered the London Parks Half Marathon in the first weekend of October and did that in 1 hour 52 minutes and deemed that as a good result. But in terms of what happened after that and the lead up, I certainly didn’t look after myself”.

His final month of preparation didn’t go that well. Trent was working 18 hour days under extreme pressure putting together a tender. There was not much work around so the tender was very important to everyone.  He was attempting to maintain his training, work and social commitments and with everything became sick.

“My main issue was a very bad chest infection. I remember being on 4 different antibiotics in the weeks leading up to the run and just before leaving for New York, my Doctor who was also an experienced marathon runner told me if I went ahead and competed, there was a chance I would die and I said ‘well, I am doing it’.”

Not withstanding, he travelled to New York as planned.

When asked about what he would do differently if he had his time over he referenced of all things, “not giving up alcohol”.

“I had been advised to give up alcohol 3 months before the run but decided to stop drinking a month out. I now know this was the worst thing to do. If I had stopped 3 months out my body would have fully detoxed however by doing what I did, my body was still repairing itself and this contributed to my sickness in that last month. Jordan kept drinking up until 36 hours before the run and was fine and I now know I should have too, or stopped 3 months out.

I arrived in New York, weak, sick, no energy and unable to breath.

I was determined to run but realistically, thought I would be done after 10 k. I am somewhat stubborn and my Boss Paul and his wife Julie had flown over specifically to support me so I wanted to at least start the run for them.”

As for the run itself and the start line?

“Apart from my wedding day and the birth of my child, it is the most amazing feeling I have had. I couldn’t even run 20 metres the day before and said I was going to run as far as I could get. I’ve never felt anything like the buzz and exhilaration of the race”

There was passion, excitement and emotion in his voice as he described the feeling of being part of 45,000 on the start bridge for the 40th edition of the New York Marathon. “Everyone was buzzed irrespective of it being their first or fifth marathon.

I can recall it so clearly. Strangers were coming up offering marking pens telling me to write my name on my chest. I asked why and they said ‘trust me, at the 20 mile mark you will be wanting people to call out your name’.

Each wave of starters was greeted with Frank Sinatra’s New York, New York blaring out with the start cannon.

Because I was sick, Jordan was going to stay with me but with so many people I lost him immediately. I instantly felt scared, alone and in fear of what would happen if I was sick and couldn’t continue.

By the 10 mile mark I was stuffed and people were yelling out my name, passing me bananas and face wipes. Every street you turned, you faced a maze of people and here I was, running around the 5 Burroughs of New York with 45,000 other people. It was awesome.

There would have been only a kilometre that wasn’t completely lined with people 5 deep.

You go through the African American part, the other Burroughs and they have their jazz playing or their bongos going. You recognised the different cultures you were going through by the types of music blaring. There were also people hanging out of their houses yelling you on and they all had their American flags – nothing can describe it. It was an amazing feeling. And some of the things you take note of. I remember a young guy who was running marathons at the time dribbling a basketball and he ran past me.

It started to get hard at about the 16 mile mark as we crossed the Queensboro Bridge in to Manhattan. I remember running on the bridge and thinking this is stuffed and as we ‘swirled’ off and under the bridge on the exit ramp saying to myself this is not fun and reality was starting to set in. The chest infection was really kicking in and an old back injury from 2003 was flaring. I was determined to keep going. I had put a lot of effort in, doing the 5 runs a week and here was the infection letting me down.

Also driving me to keep going was how hard we worked as a team. I had become very close to Paul and Julie who I referred to as my English Mum and Dad. Having them there to support me meant a great deal. I had bought them finish line tickets and now I wasn’t stopping even if it took 10 hours to get there. It’s all or nothing, 100% or not at all.”

Trent kept going.

“After 3 and a half hours I had 10 kms to go and was starting to make calculations. An hour perhaps, two even.

And then I snapped my hamstring, or so I thought.

I remember coming around a corner into a massive street (First Avenue) and it seemed you could look for miles and a plague of people lining this wide New York street. I grabbed my right leg and was sure my hamstring had snapped. The pain was excruciating.

I realised it was a severe cramp and stopped to put my leg up on an iconic New York fire hydrant. A member of the crowd jumped the barricade and put his arm around me so I could hold myself up and said ‘come on mate, you’ll be right, keep on going’. It came good and I jogged on.

The body was shutting down. I could see this little black hole in front of me, this black dot and it started getting bigger and I knew I was in big trouble. This was at about the 39 km mark and it dawned on me that I might not make it.”

When Trent’s race ended it was the fire brigade who picked him up when he collapsed. He was delirious and was throwing up repeatedly, green vomit. “It wasn’t normal, whether it was the gels or from my chest infection I don’t know.

“My next recollection was being in the back of an ambulance and being given electrolyte drinks and the discussion was of being taken to hospital. I was aware enough to know I could not afford the cost of hospital and tried to tell the ambos to just give me oxygen and I would be on my way.

I called my sister in London. I then called Paul and Julie who were in and around the finish line and they came and found me in the back of the ambulance, where I had the oxygen mask on and I broke down. Emotion came over me.

I was pleading with the paramedics to just drop me off at the hotel but they were not allowed to drop off anywhere other than a hospital. Eventually we reached a compromise and I was dropped off around the corner from the hotel.”

Paul and Julie assisted Trent in to the hotel lobby on the 35^th floor of the Mandarin Oriental where all the team were waiting and another wave of emotion came across him.

There was a change in Trent’s word flow and voice as he described this particular scene, the extreme emotion. It was an outpouring brought on by the sheer effort of the run, the pain and the illness before, during and after the run.

Everyone had their finisher medal proudly displayed around their neck, everyone that is except Trent. He had collapsed just over a kilometre from the end. When he asked the paramedics to give him oxygen and let him get on his way, he meant on his way to the finish line.

When he called his sister Hayley in London, he wanted her to get him out of the ambulance so he could finish. But she joined the paramedics and Paul and Julie in telling him to listen to his body.

He was throwing up litres of green muck, had collapsed, been picked up by the fire brigade and then taken in by the ambulance, but he wanted to go on; even though he had been told he could die.

Trent talked about the bond established between himself and Paul and Julie and the solid stainless steel bookends purchased by them as a memento of his efforts. They stand proudly in his study at home.

He said it took 6 months to feel well again.

I asked when the next marathon is. “I said I would never run another marathon until I did the New York marathon again.”

I followed up by asking what would motivate another attempt and he said doing it with the same crew again.

“I am in a different stage of my life where I look after myself, watch what I eat and drink. Perhaps the ten year anniversary in 2019.”

And the last word.

“I still look back on it as an amazing experience, it was so exhilarating”


Author: Colin Morley