How to prepare for your first half and full marathon

ARTICLE

1 June 2025

3 min read

Signed up for your first half or full mara and already stressing out? World Ultra-marathon champion Sam Gash breaks down how to prepare for your first mara so you can start and finish strong.

Everyone who’s ever run a marathon has a starting line, that moment we step beyond what’s familiar and do the thing that quietly scares us.

Mine came at Uni, when a friend told me she’d signed up for a 21km race and asked if I wanted to join. As someone who didn’t grow up sporty, my instinct was a hard ‘NO’. But underneath that initial resistance, there was a flicker, maybe it was curiosity, FOMO, or maybe a quiet knowing that I needed to say yes to something different.

So I did. And that one yes started a chain reaction I never could have imagined. Decades on, hundreds of KMs behind me and multiple ultra marathon records later; here’s everything I wish I knew before I started.

Have a plan and follow it

Running as a concept isn’t that hard. You just put one foot in front of the other and off you go, right? Unfortunately, running a marathon is an entirely different beast that requires a particular kind of preparation — aka: a training program. Why?

It allows your body to adapt without unnecessary stress and injury
It teaches you a holistic approach to running by exposing your body to different running sequences to build and improve your performance, speed, endurance and pace
It’s an accountability tool that can keep you motivated and in-check
It’s an expert-designed tool that will take you where you need to go

There’s no shortage of free running apps and programs — the key is to choose one and stick to it. Consistency is everything.

Getting the form right

Don’t overthink your form. If you’re new to running, focus on building consistency first before fine-tuning it.
Shoulders down and look ahead, this will help alleviate any neck and shoulder tension
No matter how seasoned you are, long runs inevitably cause our shoulders to creep up. While this is normal, it can cause neck tension and make it harder to recover. Be mindful when this happens and move your shoulders back down

Fuel your body, every day

When preparing for your first marathon, it's crucial to train your body to properly consume calories and hydration, especially as you approach peak training weeks. Experimenting with different fuels, like gels and electrolytes, during your long runs will help you find what works best for your body. Proper nutrition and hydration (particularly electrolytes) will optimise performance and support your recovery, ensuring you’re ready for every run and life’s daily demands.

A mental workout

Running is just as much a mental game as it is a physical one. When things get tough (and they will), try to:

Back yourself. Even when doubt creeps in, trust in your why. That belief becomes the fuel that carries you through the tough patches.
Resilience over perfection. Life will throw curveballs, missed sessions, off-pace runs, bad sleep. Don’t let them derail you. Instead, reflect on how you’ve shown up through challenges in the past and let that be your reminder: you’re stronger than you think.
Remember what you’ve already overcome. When your mind says you can’t, call on the evidence of everything you have done. You’ve faced far bigger things than a tough run. You can do this.

Run day checklist

Pack for the day ahead Get everything out the night before, so you can wake up ready to go
Eat breakfast Oats, toast with honey, eggs: whatever it is, make sure you fuel your body with carbohydrates, protein and hydration
Get in early to use the loo The term ‘runner’s runs’ exists for a reason, trust me on this one.
Challenge your mind No race ever goes to plan. When things get hard or you fall behind on pace, just remind yourself to keep placing one foot in front of the other until you cross that finish line
Eat as soon as you finish Your body needs carbs for muscle recovery, so as soon as you finish, be sure to fill up on a carb-rich meal

Marathons are no easy feat, but the deep joy and pride that comes from crossing that finish line? It stays with you. Long after the aches fade, the belief in yourself remains.

Samantha Gash

Samantha Gash is an Australian endurance athlete, inspirational speaker, author, social impact entrepreneur and mother. In 2010, she made history by becoming the youngest person and first woman in the world to complete the 4 Deserts Grand Slam ultramarathon event. She has since run numerous ultra- events around the world, and raised hundreds of thousands of dollars for charity in the process. She is passionate about using her expeditions as a vehicle for driving social change.

Disclaimer:
Copyright © 2025 AIA Australia Limited (ABN 79 004 837 861 AFSL 230043). This is general information only, without taking into account factors like the objectives, financial situation, needs or personal circumstances of any individual and is not intended to be financial, legal, tax, medical, nutritional, health, fitness or other advice. The source information of the articles is current as of the date of publication and may be subject to change. While the information contained herein is believed to be accurate, AIA Australia expressly disclaims any and all liability for representations or warranties, expressed or implied, contained in, or for omissions from, the information.

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