Oct 272015
 
Nutrition for a 100 miler

Salt – do we really need it ?

The ability to measure our sodium losses in sweat during exercise has led some to thinking that we need to replace at least some of what we lose in sweat to ensure our blood sodium levels don’t fall to levels that effect performance or health.

The thinking goes that somewhere between 230-1700mg of sodium can be lost per hour during exercise in hot conditions and we have a typical daily intake of 4g. As a consequence it can take only 2-3 hours before we deplete our sodium stores levels that effect performance. But measuring sweat sodium levels is only part of the picture – our body doesn’t particularly care what our sweat sodium concentration is (and in fact it reduces sweat sodium concentration as it acclimatises to exercising in the heat). What the body very tightly controls is our blood sodium levels and has several mechanisms to keep it within 135-145 mmol/litre range that is required for normal human function.

One thing to understand is its not the actual amount of sodium in our body that is the critical factor, its the concentration of sodium in our blood. If there is less blood then we need less sodium to keep the concentration in normal range.

Deciding we need sodium supplementation based solely on what we sweat out is like basing fat consumption based purely on how much fat we burn during exercise or basing our hydration strategy purely on how much weight we lose or our carb intake on how much energy we burn when we run. What we burn or sweat out doesn’t matter – its whats left in the body that we need to be concerned about. So when we look at fat burnt during exercise we know that we have ample supplies of fat so there is no need to take on additional fat, we know that our carb supplies will eventually run out so we need to take in additional carbs in a race but we know we don’t have to replace the whole amount we burn, we also know that the body can handle a certain level of dehydration with no adverse effects provided we drink to thirst. As far as sodium goes what we should be looking at is what happens to our blood sodium levels during exercise NOT how much sodium we lose in sweat.

Do we need to replace all of our sodium sweat losses, some of them or none of them?

Continue reading »

May 012015
 
Some of the terrain on the Big Red Run (photo courtesy Greg Donovan)

Tackling the dunes (photo courtesy Greg Donovan)

The Big Red Run is the next race on my race calendar so I thought I would share how I plan to go about training for this multi stage desert race. It is a similar format to most of the multi stage desert races around the world, with 4 shorter days of 30-42km, and then a long day of 84km.

Whenever I look at designing a training plan for a race, I analyse what factors are most important for that race, and each individual and plan accordingly.

For a multi day race there are a few key factors training should be focussed around:
1. Improving running economy
2. Decreasing risk of injury
3. Ability to run long several days in a row
4. Increasing endurance
5. Race specific training
6. Improving fat burning ability
7. Time on your feet

Let’s look at each of these in detail and see what they means in terms of training. Continue reading »

Sep 052014
 

Rinjanie finish 2

One day after Catherine and I had decided to spend a month or two in Bali between relocating within Australia Catherine stumbled upon a photo on Instagram that mentioned the Mt Rinjani Ultra. A check of dates confirmed we would be in Bali when the race was on and I quickly decided that if there was an ultra nearby then it would be criminal not to do it.

I was slightly disappointed when reading it was only 52km but then intrigued that the winning time last year was just under 15 hours. Ok it had 5800m of vert and went to an altitude of 3720m but even still 14 hours? I was in for a shock and the most testing race of my ultra career! Continue reading »

Sep 012014
 


There is a lot of discussion in the media and running circles about running technique, and specifically heel strike vs forefoot and the pros and cons of each. Unfortunately almost all the discussions have over simplified the topic and miss a few key points.

Before I go into more explanation let me summarise by saying:
1. There is nothing wrong with heel striking depending on where the rest of your body is when your heel strikes the ground.
2. Changing to a fore/mid foot strike doesn’t necessarily improve your running or decrease your risk of injuries and may even increase the risk of injury.
3. Forefoot strike is not necessarily a more effective, more economical way of running. Read on to find out why. Continue reading »

Sep 062013
 

20130822-153339.jpgEver since Hoka One One was launched a few years ago it has divided runners opinions – depending on who you speak to its either a revolutionary shoe or a fad that will disappear with time.

Since they were launched right at the height of the minimalist shoe trend they stood out amongst the zero drop minimal cushioning alternatives and if you weren’t singing Hokas praises then you were probably firmly in the side against them.

Hoka lovers claim the shoe allows them to fly downhill and run further without muscle soreness.

The detractors claim the massive cushion will decrease the proprioreceptive feedback your feet give your brain, making you a less efficient runner. They will increase ground contact time which will slow you down and the height of the shoe would increase instability making them a poor choice for trails.

Fast forward a few years later and the biggest trend in running shoes for 2014 is for light weight maximally cushioned shoes – very similar to the Hokas.

So why the swing towards maximalist cushioned shoes? Continue reading »