Everything you need to know about running a Marathon

Take a read of this blog & find everything you need to know before running your first marathon. From kit to preparation, our experts have given us great advice to share with you.
Decathlon Ireland
September 20, 2023


It's true that 26 miles (42 km) can seem daunting, but with good preparation, targeted training sessions and advice from other athletes, anyone can conquer this challenge with the right mindset and preparation. 

The Marathon's in New York (the classic race), alongside the races in Paris and Athens are now common goals shared by many runners. In Ireland, Marathon runners will likely be preparing for The Irish Life Dublin Marathon in October and if you’re preparing for your first race, or thinking of setting this goal for next year, we have some great tips to help you prepare.


Preparing for a marathon is a long-term project, both physically and mentally. If you are setting this goal, you will want to have 6-12 months ahead of your race to work up to the long distance race, particularly if you are new to the sport. You might even look into getting a coach to guide you along the way with advice, training programmes, nutrition and more.

To complete a marathon, you will need to commit to several regular and weekly running sessions. Paying close attention to your pace and your recovery between sessions to avoid injury. Your running pace for a marathon will be a key factor in completing the race, if you run too fast and you run the risk of losing your energy and stamina too early on to be able to finish. Even in training, your running pace is a key factor to build up your awareness for the race day but also to ensure you are recovered for your next run. 

“A steady pace, finishes the race”

To conclude, committing to a minimum of two runs a week with several short-distance running tests is a good starting point for "taking the leap"!  Try it out and see if you are ready to commit and sign up for your first Marathon.


Now that you feel ready to start training, it’s time to start putting a plan of action in place.

As mentioned above, running a full marathon distance is an accessible goal on the condition that you set the right targets. The most important question that you must ask yourself is simple:

What do I need to meet my target?

Indeed, there is no point running kilometres in numbers that will wear you out if your speed doesn't improve! You will exhaust your muscles and might even injure yourself by not having an effective training and recovery routine

But, before finding your pace, it is recommended to calculate your maximal aerobic speed (MAS*) which is the pace maintained for 6 to 10 minutes depending on your training level.

These running sessions can be alternated with endurance and speed sessions. For example: (10 x 400m – 2 x 10 x 200m) and sessions on track (3 x 2000 – 2 to 3 x 3000) and that’s not forgetting the stretching and recovery stages, which are keys to your success! 

Many runners will know that stretching and foam rolling are great for recovery so ensure you have a decent foam roller at least.

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But sometimes they are not enough. Sea Swimming and Cold water dips are also great for your muscles, and you can read more about the benefits here. Alternatively, some runners will opt for a regular Sports Massage or Dry Needling, to ensure their bodies are staying in peak condition and injury-free for the day of the Marathon.

An essential accessory for your marathon training is a heart rate monitor, which will enable you to optimise your capacities in accordance with your age and your breathing faculties, it will also help you keep track of your pace and  your training sessions/progress overall.


The effects of a healthy diet on well-being and sports are crucial for improving performance in training. Bear in mind that the ideal fuel for a marathon should be an appropriate intake of all the essential nutrients for the human body: proteins, carbohydrates, fats, fibres and vitamins.

Choose foods with high nutritional content like yeast, wheat, dry vegetables, fresh fruit and vegetables, but limit sugar and alcoholic spirits. The secret of a marathon runner is good hydration, an average 2.5 litres of water a day.

Diet is crucial coming up to race day, a marathon is a long event and introducing any new foods to your diet close to a race can affect your digestion, so it is important to know how your body reacts to certain foods and keep it plain and simple close to race day and try not to try anything new!


Marathon & Training shoes:

Given the high number of kilometres to be run during the preparation of a full marathon, you should invest in a good pair of running shoes, finding the most suitable shoe for the shape of your feet and your stride type.

It goes without saying, don't wear new shoes on race day, break in new shoes with some medium to long distance runs to ensure they won’t cause any blisters on the day of the marathon!

We recommend our popular Kiprun KS Light range for those preparing for a marathon or for regular runners. Sitting at a very competitive €91 the Kiprun KS Light is a lightweight and stable running shoe, designed for running outings and racing up to marathon distance.

When running the Dublin Marathon or any races in Ireland, the weather is a significant factor. Thankfully, the Kiprun KS light’s sole was designed like a car tyre for effective running without any loss of control when it rains.

The new geometry of the sole combined with a new rubber component provides the Kiprun KS light with excellent grip on wet terrain, even at top speed. Making this running shoe for men and women, perfect for running in Irish weather conditions and an ideal running shoe for the Dublin Marathon.

Shop our Kiprun KS Light running shoes

Marathon clothing:

Now that shoes are out of the way, let’s talk about the rest of your marathon apparel. Socks are inevitably the next most important piece of kit. Make sure you also have good socks made of a technical material to avoid over-heating and blisters during a race, two things a runner dreads. Particularly when running long distances such as a marathon!

Whether it’s a short or longer-distance race, it is important to be comfortable, as the slightest chafing of fabric can become very painful. On the day of the marathon, wear a breathable T-shirt that you have already worn in a race and that you know doesn't irritate you. 

As we previously mentioned, the weather is an important factor when preparing for a marathon. Knowing the weather conditions is also key for your preparation, running the Marathon in Barcelona will naturally be very different to a marathon in Dublin. Being used to running in the race day conditions, whether it be rain or shine, will ultimately help you in your preparation for the race day. Having the right kit and sufficient clothing will also make your goal easier to reach.

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Marathon supplements / nutrition:

Many marathon runners will rely on energy gels during a race to keep their bodies fueled during the marathon. At Decathlon we have a range of gels and a variety of flavours available. Find what works best for you in your training sessions and take the right fuel into your race when the day of the marathon arrives.

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Get everything you need for your marathon preparation online or in store @ Decathlon.ie.

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