Focus on Form
Rather than focusing on how tired you feel or how much farther you have to go, shift your thoughts to things that are productive. These include: form, breathing and your stride. Do a form check to make sure you're staying efficient. Your form breaks down the more fatigued you are, so at times like these, it's extra important to make sure you're not falling into bad habits. Counting your breath or strides are excellent distractions; they keep your brain engaged and is far more productive than focusing on how many repeats you have left to complete.
More: Can Running Technique Be Taught?
Relax and Run Controlled
Runners tend to tense up the more they "try" to run harder. It's an odd irony that the more you try to will yourself to run faster, the slower you end up running. It's because you're running tense. Shake out your arms, relax your jaw, unclench your fists, and stop trying so hard. It's much easier said than done, but shift your mindset from times and pace to running smooth. Picture the fastest sprinters in the world; they run totally relaxed—sometimes you can see their cheeks bouncing because they're so relaxed. You may not be the fastest sprinter, but you can still channel that fluidity. Ditch the tension, relax, and stop trying to force it.
More: How to Run Relaxed
Zone Out
The best trick to making it through a crappy workout, or any workout or race for that matter, is to get into a zone. Find a rhythm and stop thinking completely. Again, much easier said than done, but get into that zone by focusing on your running efficiencies (ie: form, breathing, stride, etc.), and looking straight in front of you. This works incredibly well if you can tuck in and run directly behind someone: focus on his or her back and don't let a large gap grow.
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Stay Positive
Yes, the workout feels lousy, but adopting a pessimistic mindset will only make it harder. In fact, it will make the whole workout a waste because chances are you'll stop, or jog it in. Flip this workout into something positive by reminding yourself that running when you feel great is easy; running when you feel like crap is what separates the tough runners from the rest. View this workout as a mental test ... where will you fall?
The hardest workouts provide opportunities to reach another level of mental toughness. Get through these days and you will gain more confidence when you step to your next starting line.
More: Running and Pain: How to Overcome Mental Blocks
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