1. Start slowly.
For the first mile, run at least 3 minutes per mile slower than you could race the distance on that day (factoring in the heat, humidity, hills, etc.). If you have no clue about your race pace, run about 2 minutes per mile slower than you have on recent long runs.
2. Take walk breaks.
A 1-minute walking break every mile allows your running muscles to recover just enough to maintain muscle resiliency into the latter stages of a long run. Beginners should start with 2 minutes of walking and 1 minute of running. After a few weeks, try 2 minutes of each. Eventually, move to whatever combination of walking and running works best for you. Just remember: You need to take breaks from the start in order to reap their restorative benefits.
More: Strategic walk breaks can make you a better marathoner
3. Pace yourself.
Run each mile after the first one at 2 minutes per mile slower than you could race that distance on that day.
4. Increase mileage.
Increase your long runs by no more than 2 miles each week.
More: 7 Mistakes to Avoid on Your Long Runs
5. Run with a group.
With the right people, you'll have added motivation yet still be able to stay with your easy running. (Be sure that the group doesn't always want to go faster than you do.) Running with a group generates stories, jokes and laughter, so long runs become enjoyable bonding experiences.
More: 5 Ways to Benefit from Group Workouts
6. Spread out your long runs.
You can safely do a long run once a week until you get up to 10 miles, at which point you should run it every two weeks. When you pass 18 miles, do your long run every third week.
I believe that running slower helps you shift into the "right brain" more readily. Spending time in this imaginative and creative center often leaves you reinvigorated.
The faster you go, the sooner you'll engage the left brain, which tends to generate a million negative messages and excuses. Running is much more fun when the right side of your brain is in control.
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