Issue: You're feeling tired with heavy legs a lot—especially during marathon or half marathon training.
Solution: It's normal to experience fatigue and less-than-fresh legs when you're training for a long-distance event. If you don't have other symptoms of an illness, you're likely feeling the accumulated effects of higher mileage and longer workouts.
Make sure your plan includes some down weeks, where your overall volume is reduced, but you maintain the rhythm (frequency) of your running. If you've just run a race, such as a half marathon, as a tune-up for your marathon, take a rest day or two after the race, ice to reduce inflammation, and complete more cross-training the week after the race.
Issue: You're able to run your workouts faster than your plan prescribes.
Solution: Use a pace calculator to make sure you assessed your fitness level appropriately when you started your training cycle. Did you base your workout splits on your most recent race results? If you're in the middle of your training cycle and did base your workout times on your recent race results, it may be because you're a less seasoned runner who is responding more quickly to the workouts than you may have originally expected. In this case, as long as you keep progressing at a gradual rate, you might end up running faster than anticipated at your race—not a bad thing.
But, if you're a more experienced runner who is running your workouts faster than prescribed on a consistent basis, you're probably pushing yourself to peak earlier than your plan dictates.
"Keep in the optimum ranges according to the pace calculator. If you go faster, that's not necessarily better," McMillan advises. He says that executing workouts isn't always intuitive. "We come from this type of football mentality of 110 percent—that you should give the workout your all and feel completely drained at the end. But, that's not really how the best can train consistently."
Issue: You're trying to PR, so that means you should push yourself to run faster than you ever have during training, so that your effort on race day feels more comfortable.
Solution: While this approach might make logical sense, it's not the ideal way to peak at the right time. "I would say that 19 out of 20 workouts should not be run this way—the efforts during your workouts should be super controlled," says McMillan. "And most people race so much now that they should be getting enough of this practice leading up to their goal races. You need to challenge the body to the right level so it can adapt. That's what brings you to a peak—it's the ability to challenge the body to just the right place so it adapts at a predictable rate."
More: How to Train for a PR
Issue: A workout run at your goal race pace feels too hard close to the race.
Solution: This could be delayed fatigue from the weeks or months of your training cycle. You might just need to rest a bit more to feel refreshed. As long as you did the right things during training and didn't suffer from a long layoff, the tapering process should make you feel ready to race.
"In the marathon, you need to respect what your training is telling you," advises McMillan. "If it's three weeks before the race and you just did your last marathon-specific workout, and it's indicating that you can only run 10 seconds per mile slower than your goal pace, then you need to adjust your goal pace. You can get into a real tough situation during the marathon if you don't adjust your pace in this case."