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4 Reasons You Struggle In The Ironman Marathon

Updated: Dec 24, 2019

So you are a middle of the pack Ironman athlete and wonder where you can make your biggest gains, the answer usually lies in the run. Although a large percentage of Ironman participants are capable of running a marathon in under four hours, in most iron-distance races less than 10 percent finish the run in under four hours.

How many times have we heard participants say, “I had a great swim, a great ride and a horrible run?” Why is this? The answer is: They walk it. There is nothing wrong with walking during an Ironman, if you plan to. However, most athletes don’t plan to walk but end up doing it anyway.

Here are the reasons for unscheduled walking and suggested plans of action to help you pick up the pace:

What happened: My nutrition plan failed.

The athlete has eaten either too much or too little on the bike. Too much snacking can cause gastrointestinal problems such as sloshing, bloating or multiple bathroom stops. Too little nutrition can lead to dehydration and/or downright bonking. Worse yet, some athletes ingest the wrong nutrition. Grabbing untested goodies at the aid station is risky at best.

Solution: Practice with products.

Each person has slightly different nutritional needs which is why it’s imperative to understand how much to ingest and what liquids and foods can safely be ingested. A sports bar or drink that tastes good at home may taste like sawdust halfway through an Ironman. Test your nutrition on your long runs, rides and bricks, at race specific heart rates. Your carbohydrate ingestion should be between 200 and 400 calories per hour and your liquid ingestion between one to one-and-a-half liters per hour, depending on your weight and metabolism. Sodium intake should be about 500 to 750mg/L of fluid intake.

What happened: I went too hard on the bike.

This is not to say you should go easy on the bike, but it’s necessary to manage your swim and bike effort so the run doesn’t suffer.

Solution: Manage your energy output.

Have a steady swim, but don’t try to break any records. We all know how hard it is to take 10 seconds off per 100 meters. The reality is that this increase in effort will only give you a six-minute advantage on the swim! The same goes for the bike portion: You can gain 20 minutes on your bike time only to lose an hour or more on your marathon. On the bike, keep your effort about five to 10 percent below your 70.3 bike effort. One hour into the bike is a common place for athletes to forget about pacing. Check your ego in at T1 and leave it there till T2.

What happened: I transitioned through T2 too quickly.

No one should leave the second transition until they can confidently run to the first aid station.

Solution: Take your time.

By the time you get off the bike, the idea of running a marathon is often unappealing. Take some time in T2 to get yourself mentally, physically and nutritionally prepared. Be efficient and orderly, but make sure you can run to at least the first aid station before leaving transition.

What happened: Overtraining.

While most people are adequately trained for an Ironman (at least well-trained enough to finish in under 17 hours), some take a leap of faith. The great majority do not taper properly. The most common mistake is when an athlete performs their longest run or bike session less than two to three weeks before the race date.

Solution: Ensure you are properly trained and tapered.

Your best bets are to get a qualified coach who understands your abilities and to be aware of overtraining. Listen to your body, and check your morning resting heart rate. If it is consistently five to 10 beats higher than normal, you need extra rest. If you have muscle fatigue that won’t subside, you may need to take unscheduled rest. The taper should be a minimum of two weeks to three weeks in order to let your body recover and rejuvenate for the race. The final week should be very easy, but it is important to keep moving.

Sisu Racing Triathlon Coach

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