• Dietitian Clare

The Journey from half marathon to 100km (part 1)

As a kid, I used to love running and was quite good during my school years. I’d grown up hearing all about the tough marathons my dad had run and was always inspired to do one!


Although after school I didn’t really run again until March 2018 (21 years old). I’d lost little bits of myself after a difficult few years but had aimed to get back to doing all the things that I once loved! So, I started running again and set myself the goal of completing the Melbourne Half Marathon.

I had 7 months to train. I was already lifting weights 4 days per week and added in 4-5 days of running on top. I was motivated and loving the training! I followed a heart rate-based training plan which consisted of 2 long slow runs and 2-3 treadmill interval sessions.

Everything was going great until the injury came… 6 weeks away from the half marathon and I had a stress fracture in my shin. I was so mad!!! I just wanted to run, but I had to stop and let it heal.

In the 6 weeks between stress fracture and half marathon, I did 1 run. A 15km trail run with my now boyfriend, Daniel. This is where the seed was planted for the 100km!

The 100km Surf Coast Century was the day prior to our run; we were looking at the race route they had run when Daniel said, “I should run that next year”. I laughed and genuinely thought he was nuts! There was no way I would be joining him, I thought it was crazy!

4 weeks later was the Melbourne half marathon. Before the race had even started, I was already feeling disheartened due to my lack of training (thanks stress fracture).

Daniel and I ran it together. It was all going well until about the 10km mark, my pace was slowing, and I was really struggling! I had to walk little sections and complained ALOT! ‘Never again’ I remember saying over and over and over!

But I made it! I finished in 2:15:42 and whilst a bit disheartened was SO proud of myself!


I later reflected on the run and my mindset and I knew I had talked myself out of it - of course, I wasn’t going to be able to do it if I was telling myself I couldn’t!

This made me determined to enter a new race and beat my time.

I made a goal for 2019; run a full marathon.

Like all New Year’s Resolutions, I kind of just forgot about it… I only ran twice a week over the summer and Christmas period but ended up entering a 22km trail run for Daniel’s birthday. I hadn’t even trained for it and still beat my time by 8 minutes!

Having a positive mindset really made a difference.


I’m honestly not really sure what happened here and how I went from “100km is nuts” to downloading myself a 100km training plan! But I did.

3 weeks after my second half marathon, my longest ever run, I began a 22-week training plan to run 100km.

The plan consisted off a 1x long run, 2-3 x medium length runs, 1 x interval session, and 1 x hill sprint session.

Example weeks:


The training started off really well! I was averaging 40km per week, which I thought was pretty good. I had backed off my weights to 2 days per week and to prevent my stress fracture re-occurring I didn’t do any runs on a treadmill as I find they hurt my shin.

I found it very interesting telling people what I was training for, some thought I was crazy, and others told me I was naive and wouldn’t be able to do it.

Although this was really frustrating to hear from people so close to me, it gave me so much more drive to show that I could do it!

I got talking to a guy that had experience in ultra-marathons and he gave me some much-needed tips:

1. You need to be running 100km per week

2. Run at a pace that you could run at for hours

3. Practice running with all your gear and nutrition/hydration plan

After this conversation, I felt extremely underprepared. I wasn’t running even half the amount of km’s that I needed too, and I had no idea about all the required gear! But nonetheless, I turned this overwhelming feeling into motivation. I completely dropped back my weights, slowly built my km’s up, purchased all the gear and started training in a pair of trail-running shoes.

Then bang, I injured my knee.

Silly me didn’t realize trail shoes are ONLY for trails, which are softer surfaces than the concrete paths I was used to running on.

At first, I thought the pain was just my body getting used to the new style of shoes, but after 3 runs it was BAD! I could barely bend my knee, never mind run on it!

2 weeks off running and various osteopaths later, I could only run on soft trails now.

With now 7 weeks to go I was behind in my training, and the furthest I had run was 35km. Not ideal!

So I set out to run my first full marathon. 5 hours later and I was ecstatic! A goal I had set 8 months prior I had ‘accidentally’ ticked off in a training run!


“Just do 50km, you wouldn’t be able to do 100”, were the comments I still received even after reaching this big milestone.

It was like pouring fuel on a fire!

5 weeks out from race day I set out on a 50km training run, I focused on my breathing and practised “Run at a pace that you could run at for hours”.

I finished it in 6 hours and was feeling amazing!



Each run I did now required 2 days of rest for my knee, with a tone of ice!

This meant that with 4 weeks to go I was only running 2-3 times per week (max of 25km per week).

Not at all ideal, but I would rather have a slower time come race day than be in pain and risk not finishing.

Continue on to part 2 if you’d like to know how I went during the race and about my nutrition and hydration plan.


©2020 by Dietitian Clare.  ABN: 41 916 976 164 

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